![Chapter 1. HISTORICAL PERSPECTIVES
I. THEORY
6
Unfortunately, Hilgard’s advanced ideas did
not catch on in the United States at the time
he presented them and were left instead to
be discovered by other soil scientists decades
after they were originally published (Brevik
et al., 2015).
Through most of human history pursuit of
soil knowledge was motivated by and linked to
agriculture. At the end of the 19th century, soil
mapping was only about 100 years old and soil
modeling had just begun. However, the slow
and steady accumulation of knowledge about
soils as well as advances in several related
fields (biology, chemistry, geography, geology,
and physics) meant that by the end of the 19th
century soil mapping and modeling was posi-
tioned to make major strides in the 20th cen-
tury. Those strides would vastly improve the
ability of soil scientists to utilize soil informa-
tion for agricultural management and would
also take soils beyond agriculture and into
areas like human health, urban planning, and
environmental quality. Soil knowledge was
poised to become a major player in sustainable
land use management.
DEVELOPMENTS IN THE 20TH
CENTURY
Much of the 20th century was, in many ways,
a golden era of soil science, particularly from the
1930s through the 1970s. During this time, budg-
ets for soil work were relatively strong, includ-
ing funding for international work in developing
countries (Brevik et al., 2015). Soil ideas were
exchanged internationally through the develop-
ment of meetings like the World Congresses of
Soil Science and conservation tillage techniques
were developed (Brevik and Hartemink, 2010).
A number of methods and standards that would
be important through the last half of the 20th
century were established, including the use of
aerial photographs as a base for soil mapping,
standards for describing soil structure, use of the
Munsell color charts (Hudson, 1999), and pub-
lication of standard soil survey laboratory and
sample collection methods in the United States
(Nettleton and Lynn, 2008). These conditions
and advances were major milestones in soil sur-
vey and set the stage for the creation of much
of the information available in the soil maps of
today. Mapping products generated during the
20th century included everything from detailed
maps to those produced at national scales
(Fig. 1.2).
The latter part of the 20th century also saw
increasing interest in sustainable land use.
However, as pointed out by Blum (1998), there
were considerable differences in the interpreta-
tion of “sustainable land use” at the end of the
20th century, and much of the discussion focused
on agricultural land use without considering
other kinds of land use. Blum (1998) proposed
the following definition for sustainable land use:
“The spatial (local or regional) and temporal
harmonization of all six soil functions [1. agri-
cultural and forest production, 2. source of raw
materials, 3. geogenic and cultural heritage form-
ing landscapes, 4. gene reserve and protection,
5. filtering, buffering, and transformation, and
6. Infrastructure] through minimizing irrevers-
ible uses, e.g., sealing, excavation, sedimentation,
acidification, contamination or pollution, salini-
zation and others.” However, there are many
challenges to defining sustainable land use, and
well into the 2000s there still was not a globally
accepted comprehensive definition (Kaphengst,
2014). Both Blum (1998) and Kaphengst (2014)
agree that sustainable land use extends beyond
the natural sciences to encompass social aspects
such as political and economic considerations,
making sustainable land use a truly transdisci-
plinary topic. Unfortunately, sustainable land use
and management was also rare at the end of the
20th century. For example, Eswaran et al. (2001)
estimated that only 10% of land in Asia was used
sustainably.
There was a general global economic down-
turn in the 1980s (Garrett, 1998) that was](https://image.slidesharecdn.com/3307216-250523154556-0eaf7d1b/85/Soil-Mapping-And-Process-Modeling-For-Sustainable-Land-Use-Management-1st-Edition-Paulo-Pereira-15-320.jpg)
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- 5. SOIL MAPPING AND PROCESS MODELING FOR SUSTAINABLE LAND USE MANAGEMENT
- 6. SOIL MAPPING AND PROCESS MODELING FOR SUSTAINABLE LAND USE MANAGEMENT Edited by Paulo Pereira Mykolas Romeris University, Vilnius, Lithuania Eric C. Brevik Dickinson State University, Dickinson, ND, United States Miriam Muñoz-Rojas The University of Western Australia, Crawley, WA, Australia; Kings Park and Botanic Garden, Perth, WA, Australia Bradley A. Miller Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany; Iowa State University, Ames, IA, United States
- 7. Elsevier Radarweg 29, PO Box 211, 1000 AE Amsterdam, Netherlands The Boulevard, Langford Lane, Kidlington, Oxford OX5 1GB, United Kingdom 50 Hampshire Street, 5th Floor, Cambridge, MA 02139, United States Copyright © 2017 Elsevier Inc. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic or mechanical, including photocopying, recording, or any information storage and retrieval system, without permission in writing from the publisher. Details on how to seek permission, further information about the Publisher’s permissions policies and our arrangements with organizations such as the Copyright Clearance Center and the Copyright Licensing Agency, can be found at our website: www.elsevier.com/permissions. This book and the individual contributions contained in it are protected under copyright by the Publisher (other than as may be noted herein). Notices Knowledge and best practice in this field are constantly changing. As new research and experience broaden our understanding, changes in research methods, professional practices, or medical treatment may become necessary. Practitioners and researchers must always rely on their own experience and knowledge in evaluating and using any information, methods, compounds, or experiments described herein. In using such information or methods they should be mindful of their own safety and the safety of others, including parties for whom they have a professional responsibility. To the fullest extent of the law, neither the Publisher nor the authors, contributors, or editors, assume any liability for any injury and/or damage to persons or property as a matter of products liability, negligence or otherwise, or from any use or operation of any methods, products, instructions, or ideas contained in the material herein. British Library Cataloguing-in-Publication Data A catalogue record for this book is available from the British Library Library of Congress Cataloging-in-Publication Data A catalog record for this book is available from the Library of Congress ISBN: 978-0-12-805200-6 For Information on all Elsevier publications visit our website at https://www.elsevier.com/books-and-journals Publisher: Candice Janco Acquisition Editor: Candice Janco Editorial Project Manager: Emily Thomson Production Project Manager: Mohanapriyan Rajendran Designer: Victoria Pearson Typeset by MPS Limited, Chennai, India
- 8. ix List of Contributors Sameh K. Abd-Elmabod National Research Centre, Cairo, Egypt; University of Seville, Seville, Spain Abdallah Alaoui University of Bern, Bern, Switzerland María Anaya-Romero Evenor-Tech, Seville, Spain Zsófia Bakacsi Hungarian Academy of Sciences, Budapest, Hungary Jasmin Baruck University of Innsbruck, Innsbruck, Austria Igor Bogunovic The University of Zagreb, Zagreb, Croatia Eric C. Brevik Dickinson State University, Dickinson, ND, United States C. Lee Burras Iowa State University, Ames, IA, United States Artemi Cerdà University of Valencia, Valencia, Spain Sabine Chabrillat GFZ German Research Center for Geosciences, Potsdam, Germany Jesus Rodrigo Comino Trier University, Trier, Germany; Málaga University, Málaga, Spain Diego de la Rosa Earth Sciences Section, Royal Academy of Sciences, Seville, Spain Daniel Depellegrin Mykolas Romeris University, Vilnius, Lithuania Soad El-Ashry National Research Centre, Cairo, Egypt Paula Escribano University of Almeria, Almería, Spain Ferran Estebaranz Universitat de Barcelona, Barcelona, Spain Kinga Farkas-Iványi Hungarian Academy of Sciences, Budapest, Hungary Luuk Fleskens Wageningen University and Research Centre, Wageningen, The Netherlands Nándor Fodor Hungarian Academy of Sciences, Martonvásár, Hungary Marcos Francos University of Barcelona, Barcelona, Spain Michele Freppaz University of Turin, Grugliasco, Italy Mónica García Denmark Technical University (DTU), Kongens Lyngby, Denmark; Columbia University, New York City, NY, United States Clemens Geitner University of Innsbruck, Innsbruck, Austria Danilo Godone Geohazard Monitoring Group, CNR IRPI, Turin, Italy Sven Grashey-Jansen University of Augsburg, Augsburg, Germany Fabian E. Gruber University of Innsbruck, Innsbruck, Austria Kati Heinrich Institute for Interdisciplinary Mountain Research, Austrian Academy of Sciences, Innsbruck, Austria Gábor Illés National Agricultural Research and Innovation Centre, Sárvár, Hungary Antonio Jordán University of Seville, Seville, Spain Yones Khaledian Iowa State University, Ames, IA, United States Annamária Laborczi Hungarian Academy of Sciences, Budapest, Hungary Beatriz Lozano-García University of Córdoba, Cordoba, Spain Oleksandr Menshov Taras Shevchenko National University of Kyiv, Kyiv, Ukraine
- 9. List of Contributors x Bradley A. Miller Iowa State University, Ames, IA, United States; Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany Ieva Misiune Mykolas Romeris University, Vilnius, Lithuania Miriam Muñoz-Rojas The University of Western Australia, Crawley, WA, Australia; Kings Park and Botanic Garden, Perth, WA, Australia Agata Novara University of Palermo, Palermo, Italy Marc Oliva University of Lisbon, Lisboa, Portugal Andreas Papritz ETH Zurich, Zürich, Switzerland Luis Parras-Alcántara University of Córdoba, Cordoba, Spain László Pásztor Hungarian Academy of Sciences, Budapest, Hungary Paulo Pereira Mykolas Romeris University, Vilnius, Lithuania Jonathan D. Phillips University of Kentucky, Lexington, KY, United States Jenny L. Richter Iowa State University, Ames, IA, United States Emilio Rodríguez-Caballero Max Planck Institute for Chemistry, Mainz, Germany; University of Almeria, Almería, Spain Thomas Schmid Center for Energy, Environment and Technology Research, Madrid, Spain Alois Simon Provincial Government of Tyrol, Innsbruck, Austria Anna Smetanova National Institute for Agricultural Research, Paris, France; Technical University Berlin, Berlin, Germany Silvia Stanchi University of Turin, Grugliasco, Italy József Szabó Hungarian Academy of Sciences, Budapest, Hungary Gábor Szatmári Hungarian Academy of Sciences, Budapest, Hungary Katalin Takács Hungarian Academy of Sciences, Budapest, Hungary Robert Traidl Bavarian Environmental Agency, Marktredwitz, Germany Xavier Úbeda University of Barcelona, Barcelona, Spain Martine van der Ploeg Wageningen University and Research Centre, Wageningen, The Netherlands Nina von Albertini Umwelt Boden Bau, Paspels, Switzerland Borut Vrščaj Agricultural Institute of Slovenia, Ljubljana, Slovenia
- 10. xi Preface Soils are the base of life on Earth. This thin layer of so-called “earth skin” provides an invaluable number of services that permit the planet to be habitable by life as it exists on Earth today. Soils are created at the interface of the lithosphere, atmosphere, biosphere, and hydrosphere. Their formation depends on par- ent material, topography, time, climate, and organisms, with other factors such as fire and humans gaining in importance. Soil formation is very slow and the soil itself is considered a nonrenewable resource over the human time scale. The expansion of human activities is induc- ing tremendous soil degradation, without precedent in Earth’s history. This uncontrolled expansion is leading to an important decrease in the services provided by soils at a global scale. Soil degradation is caused by climate change, conflict and wars, land use changes, deforestation, and other activities, threaten- ing overall global food security, environmental sustainability and trigger famine, conflicts and wars. Stopping this trend is a challenge for our time. Addressing this challenge is a duty and responsibility that we have to future genera- tions to ensure them the provision of soil ser- vices that have existed in the past and that we have today. In this context, we scientists need to create knowledge, identify problems and offer solutions to invert this dynamic. It is essential that we provide sustainable measures to utilize soil resources without dilapidating or degrad- ing them. Sustainable soil management is not an option, it is a necessity and a responsibility that scientists, stakeholders, decision makers and all the other agents involved in land man- agement have to acknowledge and respond to out of respect for future generations and the health of planet Earth. A key piece to understanding sustainable soil management is to recognize the unique characteristics of different soils as they are dis- tributed across landscapes. Soil spatial vari- ability can only be understood with modeling and maps. Maps are a simple, synthetic and clear representation of reality. Maps are spatial models that are tremendously useful for scien- tists to develop research and for land managers to intervene appropriately in the territory they control to protect and restore soil. Soil maps can identify and predict areas that are more vulner- able to degradation and thus promote sustain- able use of the land to facilitate better and more customized management, contributing to the optimal allocation of resources for continued long-term use of the soil resource. Soil Mapping and Process Modeling for Sustainable Land Use Management is an origi- nal book and the first published on this topic. The intent is to transfer knowledge of the cur- rent state of the art to students, scientists, land managers, and stakeholders to facilitate sus- tainable use of land resources. The chapters of this book were written by leading scientists who have several years of experience in this field. The book is organized in two parts. The first is composed of six chapters focused on the
- 11. Preface xii theoretical aspects of soil mapping and process modeling, where historical and current aspects of soil mapping and sustainable land use man- agement are analyzed. The importance of the integration of soil mapping and traditional know-how for sustainable use of the land, use of remote sensing for mapping and monitoring, application of GIS tools to soil mapping, analy- sis, and land use management, and the use of soil mapping and process modeling to address modern challenges are also discussed. The sec- ond part of the book has a practical orientation, where the methods discussed in the first part have been applied to several areas in Europe, the United States, and Africa. Soil Mapping and Process Modeling for Sustainable Land Use Management is a product of several years of research and collaboration between the editors and authors of the book. The idea to create this book was discussed prior to and during the European Geoscience Union Assembly in Vienna in 2015, during the organi- zation and execution of a short course titled “Short course on soil mapping methods.” Some of the authors of this book have collaborated for a decade and we joined our knowledge and efforts to provide what we hope will be an important contribution about Soil Mapping and Process Modeling for Sustainable Land Use Management. We truly believe this topic repre- sents a crucial challenge in the present that will significantly impact future generations. We would like to express our appreciation for the enormous support provided by Marisa LaFleur, Emily Thomson, and Rajesh Manohar, for their incredible editorial and technical sup- port that was fundamental for the compilation of this monograph. We would also like to thank all the contributing authors that helped make it possible to bring this book to light. It was only with their commitment and enthusiasm that this project became a reality. The Editors Paulo Pereira Eric C. Brevik Miriam Muñoz-Rojas Bradley A. Miller
- 12. 3 Soil Mapping and Process Modeling for Sustainable Land Use Management. DOI: © Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/B978-0-12-805200-6.00001-3 2017 Historical Perspectives on Soil Mapping and Process Modeling for Sustainable Land Use Management Eric C. Brevik1 , Paulo Pereira2 , Miriam Muñoz-Rojas3 , Bradley A. Miller4,5 , Artemi Cerdà6 , Luis Parras-Alcántara7 and Beatriz Lozano-García7 1 Dickinson State University, Dickinson, ND, United States 2 Mykolas Romeris University, Vilnius, Lithuania 3 The University of Western Australia, Crawley, WA, Australia 4 Iowa State University, Ames, IA, United States 5 Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany 6 University of Valencia, Valencia, Spain 7 University of Córdoba, Cordoba, Spain C H A P T E R 1 INTRODUCTION Basic soil management goes back to the earli- est days of agricultural practices, approximately 9000 BCE. Through time humans developed soil management techniques of ever increasing complexity, including plows, contour tillage, ter- racing, and irrigation. Spatial soil patterns were being recognized as early as 3000 BCE, but the first soil maps did not appear until the 1700s and the first soil models finally arrived in the 1880s. The beginning of the 20th century saw an increase in standardization in many soil science methods and wide-spread soil mapping in many parts of the world, particularly in developed countries. However, the classification systems used, mapping scale, and national coverage varied considerably from country to country. Major advances were made in pedologic mod- eling starting in the 1940s, and in erosion mod- eling starting in the 1950s. In the 1970s and 1980s advances in computing power, remote and prox- imal sensing, geographic information systems (GIS), global positioning systems (GPS), and sta- tistics and spatial statistics among other numeri- cal techniques significantly enhanced our ability to map and model soils. These types of advances positioned soil science to make meaningful con- tributions to sustainable land use management as we moved into the 21st century.
- 13. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 4 BRIEF REVIEW OF DEVELOPMENTS PRIOR TO THE 20TH CENTURY In many respects we can say that soil science has a long prehistory and a brief history (De la Rosa, 2008, 2013). Soil science has long stand- ing ties to agriculture. The earliest evidence of agricultural practices comes from an area near Jarmo, Iraq dating to 9000 BCE, and there is evidence of irrigation from southern Iraq dat- ing to 7500 BCE (Troeh et al., 2004). Between 6000 and 500 BCE soil management techniques including early plows, terracing, drainage, and contour tillage were developed in various parts of Europe (Fig. 1.1) (Brevik and Hartemink, 2010) and by the Maya and pre-Inca in Central and South America, who also engineered soils (Hillel, 1991; Jensen et al., 2007). Along with advances in production, various forms of land degradation, including soil erosion and salinization, became a problem very early in the history of agriculture (Hillel, 1991; Troeh et al., 2004). It is likely that early humans used a trial and error approach to determine which sites would work well for agricultural produc- tion, but by 3000–2000 BCE there is good evi- dence that humans were recognizing spatial patterns in soil and utilizing the more desirable soils for cropping (Krupenikov, 1992; Miller and Schaetzl, 2014). During the Sumerian and Babylonian civilizations, until 1000 BCE, agri- culture continued to be developed. Soils were distinguished by their natural fertility and apti- tude to support irrigation. From 2000 BCE the Greeks improved numerous treatises in which they explained their knowledge about differ- ent soil properties. Soil erosion was a serious problem in Ancient Greece; therefore it was thoroughly studied. Likewise, by about 500 BCE settlement patterns in many parts of the world were correlated to the kinds of soils pre- sent (Miller and Schaetzl, 2014). The Romans continued the Greek’s studies. From 200 BCE, Catón, Varrón, Plinio, and later (in the first cen- tury AC) Columela proclaimed agriculture as a science, and considered soil as one of the most important components. Knowledge about a subject must be accu- mulated before that subject can be classified (Marbut, 1922), and classification of soils began thousands of years ago. Early examples include the Chinese classification from 2000 BCE (Gong et al., 2003) and that of the Greek philosopher Theophrastus from c. 300 BCE (Brevik and FIGURE 1.1 Terraces, such as these in Spain, have been used for thousands of years to make steep slopes suitable for agricultrual production. Source: Photograph by Artemi Cerdà.
- 14. Brief Review of Developments Prior to the 20th Century I. THEORY 5 Hartemink, 2010). In addition, the Romans developed a soil classification system for the soils of Italy and improved previous knowl- edge about soil fertility and ways to maintain and restore it. There are very important and interesting written works, such as Res Rustica (Columela, 42 CE) where the author describes soils in detail. In the Western Hemisphere the Maya civilization in Central America created a detailed soil classification that they used to guide their agricultural decisions long before Europeans arrived (Wells and Mihok, 2010). Therefore humans have sought to describe and manage soils based on their properties and have recognized a spatial distribution to those properties for thousands of years. However, while this was a precursor to soil mapping and modeling, recognizing the existence of spatial distribution of soil properties is differ- ent than actually mapping and modeling those properties. The first recordings of spatial soil infor- mation were written accounts linking soil properties and attributes to land ownership documents. These were utilized in China as early as 300 CE, Arabia as early as 500 CE, and Europe as early as 800 CE (Miller and Schaetzl, 2014). Soil properties and attributes were first mapped in Europe beginning in the 1700s (Brevik and Hartemink, 2010), some- thing that was made possible by improved base maps (Miller and Schaetzl, 2014). The 1800s saw increasing interest in soil mapping in Europe and the United States; much of the mapping in the United States was done by state geological surveys in an attempt to jus- tify their budgets to state legislatures that were looking for a return on their investment (Aldrich, 1979). In parallel with these advances in the first recordings of spatial soil information, it is important to point out the treatise “Agricultura General” (de Herrera, 1513), based on the pre- vious studies of Columela, where the author introduced highlighted points about soil quality. After that, during the 19th century, advances were made in many areas that would ultimately prove to be important to under- standing soil science for the purpose of sus- tainable management. The “Mineral Theory” of plant nutrition was first proposed by C. Sprengel in the late 1820s (Feller et al., 2003a) and became widely accepted after von Liebig’s (1840) publication of Chemistry as a Supplement to Farming and Plant Physiology, which was a major improvement for both soil fertility and soil chemistry (Sparks, 2006). Many advances were made in soil mapping and cartography in both Europe and the United States, and the soil profile concept was developed (Brevik and Hartemink, 2010). Through his work on the influence of earthworms on soil development, Charles Darwin became a pioneer in soil biol- ogy (Feller et al., 2003b). A major breakthrough in soil mapping and modeling occurred in Russia with the pub- lication of Dokuchaev’s (1883) classic work “Russian Chernozem.” This work included a map showing the distribution of Chernozems in European Russia, but more importantly it introduced the concept of soil forming factors that ultimately led to the recognition of soil science as a stand-alone scientific discipline (Muir, 1962; Krupenikov, 1992; Krasilnikov et al., 2009). Dokuchaev’s functional–factoral model was one of the first developed to explain soil formation (Brevik et al., 2016) and introduced the five soil forming factors: climate, parent material, organisms, topogra- phy, and time (Brevik and Hartemink, 2010). These five factors would eventually be cast into a state-factor model by Jenny, one of the most influential models in the history of soil science. Therefore Dokuchaev’s work remains highly influential to the current day. Eugene Hilgard published ideas about soil formation quite similar to Dokuchaev’s in 1860 (Hilgard, 1860), and for these ideas Jenny (1961) felt that Hilgard should be regarded as a cofounder of modern soil science along with Dokuchaev.
- 15. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 6 Unfortunately, Hilgard’s advanced ideas did not catch on in the United States at the time he presented them and were left instead to be discovered by other soil scientists decades after they were originally published (Brevik et al., 2015). Through most of human history pursuit of soil knowledge was motivated by and linked to agriculture. At the end of the 19th century, soil mapping was only about 100 years old and soil modeling had just begun. However, the slow and steady accumulation of knowledge about soils as well as advances in several related fields (biology, chemistry, geography, geology, and physics) meant that by the end of the 19th century soil mapping and modeling was posi- tioned to make major strides in the 20th cen- tury. Those strides would vastly improve the ability of soil scientists to utilize soil informa- tion for agricultural management and would also take soils beyond agriculture and into areas like human health, urban planning, and environmental quality. Soil knowledge was poised to become a major player in sustainable land use management. DEVELOPMENTS IN THE 20TH CENTURY Much of the 20th century was, in many ways, a golden era of soil science, particularly from the 1930s through the 1970s. During this time, budg- ets for soil work were relatively strong, includ- ing funding for international work in developing countries (Brevik et al., 2015). Soil ideas were exchanged internationally through the develop- ment of meetings like the World Congresses of Soil Science and conservation tillage techniques were developed (Brevik and Hartemink, 2010). A number of methods and standards that would be important through the last half of the 20th century were established, including the use of aerial photographs as a base for soil mapping, standards for describing soil structure, use of the Munsell color charts (Hudson, 1999), and pub- lication of standard soil survey laboratory and sample collection methods in the United States (Nettleton and Lynn, 2008). These conditions and advances were major milestones in soil sur- vey and set the stage for the creation of much of the information available in the soil maps of today. Mapping products generated during the 20th century included everything from detailed maps to those produced at national scales (Fig. 1.2). The latter part of the 20th century also saw increasing interest in sustainable land use. However, as pointed out by Blum (1998), there were considerable differences in the interpreta- tion of “sustainable land use” at the end of the 20th century, and much of the discussion focused on agricultural land use without considering other kinds of land use. Blum (1998) proposed the following definition for sustainable land use: “The spatial (local or regional) and temporal harmonization of all six soil functions [1. agri- cultural and forest production, 2. source of raw materials, 3. geogenic and cultural heritage form- ing landscapes, 4. gene reserve and protection, 5. filtering, buffering, and transformation, and 6. Infrastructure] through minimizing irrevers- ible uses, e.g., sealing, excavation, sedimentation, acidification, contamination or pollution, salini- zation and others.” However, there are many challenges to defining sustainable land use, and well into the 2000s there still was not a globally accepted comprehensive definition (Kaphengst, 2014). Both Blum (1998) and Kaphengst (2014) agree that sustainable land use extends beyond the natural sciences to encompass social aspects such as political and economic considerations, making sustainable land use a truly transdisci- plinary topic. Unfortunately, sustainable land use and management was also rare at the end of the 20th century. For example, Eswaran et al. (2001) estimated that only 10% of land in Asia was used sustainably. There was a general global economic down- turn in the 1980s (Garrett, 1998) that was
- 16. Developments in the 20th Century I. THEORY 7 accompanied by corresponding declines in soil science budgets (Hartemink and McBratney, 2008). However, new tools and technologies such as GIS, GPS, remote and proximal sens- ing techniques, and the emergence of more robust statistical methods and spatial statistics helped to overcome some of the obstacles cre- ated by reduced financing. The availability of inexpensive, increasingly powerful computers allowed for the storing and rapid processing of large amounts of data. The ability to collect environmental covariates with proximal and remote sensing coupled with spatial statistics and other numerical techniques allowed greater detail in the mapping of soil properties as well as better quantification of those properties (Brevik et al., 2016). While there is still much left to accomplish to improve soil mapping products to support the types of models that are essential for sustainable land management (Sanchez et al., 2009), by the end of the 20th century soil surveys had recognized the need FIGURE 1.2 Examples of soil maps created by national soil survey programs during the 20th century include detailed maps such as the 1:15,840 map from the United States (left; Jones, 1997) and less detailed maps such as the national map of Portugal at the scale of 1:1,000,000 produced in 1949 (right) (http://esdac.jrc.ec.europa.eu/images/Eudasm/PT/port_x21. jpg).
- 17. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 8 to provide more quantitative data (Indorante et al., 1996) and soil maps were moving from traditional static paper maps to digital prod- ucts (Minasny and McBratney, 2016). This set the stage for additional advances in the 21st century. National Soil Mapping Programs Detailed nationally organized soil survey began in many parts of the developed world in the first decades of the 20th century. This began in the United States in 1899 (Marbut, 1928) and rapidly spread to many other countries (Table 1.1). By the end of the century, several developed countries had detailed soil maps available for portions of the country that could be used to assist with management decisions. However, the amount of land surveyed and the map scale of that coverage varied consid- erably between countries, as did the soil char- acteristics and depth of exploration that each country chose to base their maps on. Often the mapping focused on soil properties and attrib- utes important to agricultural or forestry pro- duction. Table 1.2 presents information on the mapping status of several developed countries at or near the end of the 20th century based on the most detailed maps produced by their national soil mapping program. It shows that mapping coverage ranged from essentially complete (100%) to barely mapped (0.25%) and that map scales for national mapping programs ranged from 1:2000 to 1:126,720, with the most common mapping scales being about 1:25,000– 1:50,000 (Fig. 1.3). Some countries (e.g., Austria, Greece, Portugal, Sweden, and the United Kingdom) focused on agricultural areas, while a few countries (e.g., Bulgaria, Croatia) pro- duced maps at a larger scale (1:1000–1:10,000) than their typical national soil mapping scales (1:25,000–1:50,000 for Bulgaria and Croatia, respectively) as part of their national surveys to address selected areas with special problems or needs including irrigation, drainage, con- tamination, and remediation (Jones et al., 2005). A number of different soil taxonomic systems were also employed in undertaking the map- ping, often developed to address problems or needs that were very specific to each individual country (Krasilnikov et al., 2009). The combina- tion of highly variable mapping coverage and scale between countries and the lack of a com- mon nomenclature to communicate soil infor- mation led to nonuniform coverage that, along with a lack of quantitative soil information in most soil mapping, impeded the inclusion of soil information in modeling to support land management decisions (Sanchez et al., 2009). Soil mapping and soil classification are mutually dependent activities (McCracken and Helms, 1994); therefore the quality of soil classification systems is closely related to the quality of soil mapping and vice versa (Cline, 1977). For this reason, it is important that soil mapping and soil classification be studied jointly when evaluating our understanding of soils. Ideas about soil classification changed considerably over the 20th century in several countries, and dozens of countries have their own classification systems. These systems TABLE 1.1 The Beginning Date for Detailed Nationally Organized Soil Survey for Select Countries Country Date Country Date United States of America 1899 Sri Lanka 1930 Russia 1908 China 1931 Canada 1914 Poland 1935 Australia 1920s The Netherlands 1945 Great Britain 1920s Ghana 1946 Mexico 1926 Malaysia 1955 Source: Brevik, E.C., Calzolari, C., Miller, B.A., Pereira, P., Kabala, C., Baumgarten, A., et al., 2016. Soil mapping, classification, and modeling: history and future directions. Geoderma 264, 256–274. http://dx.doi.org/10.1016/j.geoderma.2015.05.017.
- 18. Developments in the 20th Century I. THEORY 9 TABLE 1.2 Percent Country Mapped at a Detailed Scale by the End of the 20th Century for Several Countries, Showing the Range in Mapping Coverage and Scale Even in Developed Countries Country %Mapped Scale Additional Notes Reference Bulgaria 100 1:25,000 1:10,000 scale mapping underway, and selected problem areas at scales of 1:1000–1:5000 Kolchakov et al. (2005) Croatia 100 1:50,000 Some 1:5000–1:10,000 scale maps available for areas with special needs Bašić (2005) Czech Republic 100 1:5000–1:50,000 All but urban areas mapped Němeček and Kozák (2005) Hungary 100 1:25,000 70% of agricultural areas mapped at 1:10,000 Várallyay (2005) The Netherlands 100 1:50,000 van der Pouw and Finke (2005) Slovenia 100 1:25,000 Vrščaj et al. (2005) Belgium 85 1:20,000 Dudal et al. (2005) USA >85 1:15,840–1:24,000 Indorante et al. (1996) Romania 80 1:50,000–1:100,000 Munteanu et al. (2005) Portugal 55 1:50,000 Gonçalves et al. (2005) Ireland 44 1:126,720 Lee and Coulter (2005) Austria 38 1:25,000 Larger scale soil taxation survey maps (1:2000) are also available. All land under agricultural use mapped Haslmayr et al. (2016) Finland 33 1:20,000–1:50,000 Sippola and Yli-Halla (2005) United Kingdom ~24 1:25,000–1:63,360 About 24% of England and Wales, most of the arable land in Scotland, all of Northern Ireland at 1:50,000 Thompson et al. (2005) Germany 13+ 1:25,000 Some state soil quality maps are available for about 48% of Germany at 1:5000 and 1:10,000 Zitzmann (1994), Eckelmann (2005) France ~12 1:100,000 King et al. (2005) Switzerland 7 1:25,000 Bonnard (2005) Greece 6 1:5000–1:20,000 About 39% of the high-quality agricultural land mapped Yassoglou (2005) Sweden 0.25 1:20,000 About 3% of the arable land mapped Olsson (2005) were often developed to address soil proper- ties or management needs that were specific to the country in which they were developed, and it can be difficult to correlate the system of one country to the soil classification sys- tems of other countries (Krasilnikov et al., 2009). By the early 2000s two classification systems had become the most widely utilized
- 19. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 10 in the world, US Soil Taxonomy and the World Reference Base (WRB) (Brevik et al., 2016). However, a soil classification system that established an international standard had not been agreed on by the end of the 20th century. A uniform international system of soil clas- sification that communicates a wide range of information about the soils classified and mapped would facilitate international com- munication (Sanchez et al., 2009; Hempel et al., 2013). Such standardization would sup- port the compilation of national mapping efforts at a variety of scales and thus the use of spatial soil information for modeling in support of sustainable land management over large areas. Models in Support of Soil Mapping and Land Use Management Several models have been developed to explain soil formation, and many of these models have also been used in support of soil mapping. One of the most influential models of soil formation is that of Jenny (1941), who considered soil as a dynamic system and cast the soil forming factors that had been discussed FIGURE 1.3 Soil use capacity in Portugal mapped at the scale of 1:50,000. Map produced in 1980. Source: http://esdac.jrc. ec.europa.eu/images/Eudasm/PT/port2_20d.jpg.
- 20. Developments in the 20th Century I. THEORY 11 by Hilgard (1860) and Dokuchaev (1883) into a state-factor equation: s cl,o,r, p,t,... = f ( ) (1.1) This equation can be quantitatively solved in theory, but a number of obstacles to suc- cessfully doing so still exist despite many attempts to solve it (Yaalon, 1975; Phillips, 1989). Rather, Jenny’s model has been influ- ential because it changed the way that soil studies were approached, leading to studies where one factor was allowed to vary while the others were held constant, thereby inves- tigating the influence of the varying factor on soil properties and processes. This approach is also important for sustainable management planning, in that it views the soil as a part of the overall environment (Jenny, 1941) and thus can be used to investigate how a given change in the overall environment, including changes due to human management, influence the soil system (Yaalon and Yaron, 1966). Finally, from a mapping perspective, Jenny’s model has been important in that it helps explain and predict the geographic distribution of soils (Holliday, 2006), a fundamental aspect of mapping. Another pedogenic model that has been important in understanding how soil changes was the process-systems model developed by Simonson (1959). While Jenny focused on exter- nal factors that influenced the final soil cre- ated at a given location, Simonson focused on processes that occur within a soil. Also, unlike Jenny’s model, Simonson’s model was not cast into potentially quantifiable terms. It was a qualitative model meant to help the user under- stand soil processes, but that was not designed to be mathematically solved. Simonson’s model is particularly useful in the study of soil indi- viduals (Schaetzl and Anderson, 2005), which makes its concepts useful to understand human impacts on the soil resource at very large scales. The process-systems approach is also more useful than the functional–factoral approach to understand movement in a soil–landscape (Wysocki et al., 2000), which brings soil– landscape modeling closer to a mass balance approach. A large number of the legacy soil maps available today, which still serve as the single largest source of accessible soil mapping data (Brevik et al., 2016), were created using soil–landscape relationship models. Once the relationship between the soils in a given area and the landscape were understood, soil– landscape models allowed a soil surveyor to map the soils in a given area with reasonable speed and accuracy using a minimal number of soil samples. To define reasonable accuracy the USA National Cooperative Soil Survey (NCSS) expected soil maps based on soil– landform relationships to have 50% or greater purity in soil map units. The understanding of soil– landform relationships was advanced by a number of studies beginning in the 1930s. Soil geomorphology studies in the United States from the 1930s through the 1970s made major contributions to this understanding (Brevik et al., 2015), as did work in Africa (Milne, 1935), Europe (Gerrard, 1992), and Australia (Butler, 1950). In the modern world, soil–landscape models have had a great influence on mapping and sustainable management through their impact on legacy maps. Models are increasingly being used as deci- sion support systems (DSSs), which combine available soil, climate, and land use and man- agement data from different sources. DSS can evaluate information under different scenarios helping to support complex decision-making and problems. Among DSS the MicroLEIS DSS has been widely used in land evalua- tion (De la Rosa et al., 2004) to assist decision- makers with specific agro-ecological problems. MicroLEIS was designed as a knowledge-based approach, incorporating a set of information tools, linked to each other. Thus custom appli- cations can be performed on a wide variety of
- 21. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 12 problems related to land productivity and land degradation. A major area of interest as we neared the end of the 20th century involved the role of soils in the carbon cycle. Some of the main challenges with soil carbon monitoring include the large amount of work needed to collect the neces- sary data and the consequently high costs com- pounded by the lack of consistency between different methods of data collection. To over- come these difficulties, several soil carbon models have been developed in the last few decades with different features and limitations, e.g., CENTURY (Parton et al., 1987), RothC (Coleman and Jenkinson, 1996), and CarboSOIL (Muñoz-Rojas et al., 2013). These models can be linked to spatial data sets (soil, land use, climate, etc.) to assess soil organic C dynamics and to determine current and future estimates of regional soil C stocks and sequestration (Falloon et al., 1998). Recognizing Erosion as a Problem Soil erosion is one of the major issues that threatens the sustainable use of the world’s soil resources (Pimentel et al., 1995). Soil erosion problems have led to major prob- lems for civilizations worldwide dating back thousands of years (Diamond, 2005). With the exception of some selected individuals who sought to bring attention to the problem, erosion was not widely recognized as a seri- ous issue until about 100 years ago (Brevik and Hartemink, 2010). In the early 1900s in the United States, Milton Whitney, the head of the Bureau of Soils, hired William John McGee and Edward Elway Free to lead stud- ies in soil erosion by water and wind, respec- tively (Brevik et al., 2015). McGee (1911) and Free (1911) both produced influential pub- lications that provided in-depth reviews of the status of soil erosion knowledge to that time and presented the results of new studies that investigated erosion processes as well as ways to prevent erosion. Free’s work has been particularly praised from a soil science per- spective because it may be the first work to recognize the impact of windblown materials on soil genesis rather than just investigating wind and windblown materials as a geomor- phic process and deposit. Despite these advances, soil erosion was not recognized as a problem by many in the United States until the great environmental disaster known as the Dust Bowl, which lasted through the drought stricken 1930s in the Great Plains of the United States. The Dust Bowl was marked by extreme water and wind erosion of exposed production agriculture soils; by 1938 it was estimated that 4,047,000ha of land had lost the top 12.5cm of its topsoil and another 5,463,000ha had lost at least 5cm of topsoil, representing an average loss of 1,076,000kg of soil ha−1 (Hansen and Libecap, 2004). In response to this soil loss the Soil Erosion Service (SES) was formed in 1933 under the direction of Hugh Hammond Bennett as part of President Franklin D. Roosevelt’s pub- lic works legislation. The SES later became the Soil Conservation Service (SCS) by an act of Congress in 1935 (Helms, 2008). The SES rapidly established several erosion projects that tested and demonstrated soil conserva- tion measures (Helms, 2010) and conservation tillage techniques were developed (Holland, 2004). When similar drought conditions occurred in the Great Plains again in the 1950s and 1970s, erosion on the scale of the Dust Bowl did not occur thanks to conservation measures that had been implemented during and following the 1930s (Hansen and Libecap, 2004). Still, soil erosion continued to be a major problem. In a study conducted near the end of the 20th century, Pimentel et al. (1995) esti- mated that approximately one-third of the world’s agricultural lands had been lost to erosion in the previous 50 years, with about 1.0 × 106 ha of additional agricultural land lost
- 22. Developments in the 20th Century I. THEORY 13 annually as a consequence of accelerated soil erosion. Soil losses to erosion were estimated as 17Mgha−1 year−1 in the United States and Europe and 35Mgha−1 year−1 in Asia, Africa, and South America (Pimentel et al., 1995). It was estimated that soil erosion cost the United States $27 billion annually in onsite costs and $17 billion annually in offsite costs, for a total of $44 billion annually, or about $100 annu- ally ha−1 of cropland and pasture. The cost of preventing that erosion was estimated to be $8.4 billion annually. These values would be approximately $68.5 billion annually, $156 annually ha−1 , and $13 billion annually, respectively, in 2015 dollars (US BLS, 2016). In all respects these numbers indicated a seri- ous environmental problem that needed to be solved to attain sustainability. By the end of the 20th century the United States was probably the only country that had long-term soil erosion data collected using standardized methods; other countries had more sporadic (Cerdan et al., 2010) and/or shorter term (Dregne, 1995) erosion data cov- erage. In fact, Morgan and Rickson (1990) state that as we neared the end of the 20th century, the annual extent of erosion was not known for a single country in Europe. What was known of erosion rates in countries other than the United States was assessed primarily through models of large areas (Yang et al., 2003; Cerdan et al., 2010). That being said, erosion issues were being recognized and documented in other parts of the world during the 20th cen- tury (Morgan et al., 1998a), even if the overall effort did not have the same level of national coordination as seen in the United States. While agriculture has been practiced for millennia in Europe, there was not wide-spread concern about the effects of erosion and other agricul- turally related environmental problems until the second half of the 20th century (Morgan and Rickson, 1990; Stoate et al., 2001). Strong interest in soil erosion began in New Zealand in the 1930s, but the first systematic national assessment of soil erosion did not occur until the 1970s (Dregne, 1995). Within Australia, where soil conservation efforts are primar- ily the responsibility of the individual States and Territories, New South Wales established a SCS in 1938, but the first national assessment of land degradation, including soil erosion, did not occur until 1975 (Dregne, 1995). Likewise, wide-spread concern over soil erosion did not take hold in Africa or India until later in the 20th century (Pretty and Shah, 1997). Pimentel et al. (1995) estimated that soil ero- sion cost $400 billion annually worldwide, or about $70person−1 year−1 . This translates into about $623 billion annually in 2015 dollars (US BLS, 2016), which is about $85person−1 year−1 at the world’s present population of approxi- mately 7.3 billion (US Census Bureau, 2016). Panagos et al. (2015) estimated that early 21st century soil losses to erosion averaged 2.46Mgha−1 year−1 in Europe while Verheijen et al. (2009) estimated that soil formation in Europe only averaged 1.4Mgha−1 year−1 , indi- cating that soil in Europe was still being lost to erosion much more rapidly than it was being replaced by pedogenesis as the 20th century ended. In response to soil erosion issues, many countries or other governmental agencies developed programs that provided incen- tives and/or requirements for farmers to con- serve soil (Morgan and Rickson, 1990; Dregne, 1995; Pretty and Shah, 1997), although in many countries there was still a need to develop soil conservation programs even late into the 20th century and beyond (Morgan and Rickson, 1990; Fullen, 2003). While the details of these programs differ considerably in terms of conservation techniques promoted and the approach to motivate farmers to participate, they shared the general theme that soil conser- vation provides a public benefit that is deserv- ing of public investment (Fullen, 2003; Troeh et al., 2004). However, farmer perception of the erosion problem and how to best address it, or
- 23. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 14 even if it needs to be addressed, has often been different than that of scientists. In a study in the United States, farmers tended to disagree with government assessment of what constituted highly erodible land and did not accurately perceive the severity of erosion occurring in their fields. The farmers were concerned about potential economic losses through reduced crop yields but did not see erosion as a problem in and of itself (Osterman and Hicks, 1988). In addition, there is debate over the best way to administer conservation programs, with some contending that the conservation programs developed in the 20th century failed to con- serve soil, failed to spend program funding wisely, and in some cases actually increased erosion (Pretty and Shah, 1997; Boardman et al., 2003). Erosion Modeling To truly understand and address a prob- lem such as soil erosion at the landscape scale, it is necessary to be able to model it. It is also important to note that soil mapping is an important part of modeling soil ero- sion (Fullen, 2003), because the map provides many key model variables. To that end, sev- eral soil erosion models were developed dur- ing the 20th century. In many respects the United States led the way in erosion mod- eling, beginning with the US Department of Agriculture’s (USDA) development of the Universal Soil Loss Equation (USLE) in the 1950s. The USLE was developed to predict annual losses due to rill and interill erosion in the eastern half of the United States (Troeh et al., 2004). It was widely used and its use was rapidly extended beyond the area it was developed for, but it did not work well out- side the eastern United States. To address this issue the modified USLE was released in 1978 followed by the revised USLE (RUSLE) in 1992 (Troeh et al., 2004). The RUSLE and its improved versions have become one of the most utilized soil erosion models world- wide to estimate annual soil loss to water ero- sion (Fig. 1.4) (Pal and Al-Tabbaa, 2009; Boni et al., 2015). In recent years, RUSLE has been adopted for use with computer systems, but it was originally developed to be solved in the field using paper tables and graphs (Troeh et al., 2004). RUSLE2, a 21st century improve- ment on RUSLE, now provides calculations at daily time steps, but still does not include gully erosion and has not been tested at the watershed scale. Another commonly used water erosion model available from USDA is the Water Erosion Prediction Project (WEPP). The devel- opment of WEPP began in 1985 with initial model delivery in 1995. The WEPP was cre- ated to simulate physical processes that influ- ence water erosion such as infiltration, runoff, raindrop and flow detachment, sediment transport and deposition, plant growth, and residue decomposition to replace empirically based erosion prediction models (Flanagan et al., 2007). The most widely used wind ero- sion model developed by USDA is the Wind Erosion Prediction System (WEPS), which was developed beginning in 1985 (Wagner, 2013). The WEPS simulates weather and field condi- tions to estimate wind erosion losses (Troeh et al., 2004). A weakness in the soil erosion models available from USDA at the end of the 20th century was that water and wind erosion could not be estimated within a single model, and therefore had to be modeled separately when estimates of both were desired (Langdale et al., 1991; Cooper et al., 2010). There have been efforts to combine WEPP and WEPS to create a single water and wind erosion model platform (Flanagan et al., 2007). Soil phases as mapped on National Cooperative Soil Survey maps were also used to estimate total erosion in the later part of the 20th century (Olson et al., 1994).
- 24. Developments in the 20th Century I. THEORY 15 FIGURE 1.4 Soil loss by water erosion in the European Union mapped using the RUSLE model. Source: http://ec.europa. eu/eurostat/statistics-explained/index.php/Agri-environmental_indicator_-_soil_erosion.
- 25. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 16 Other soil erosion models were also devel- oped in the 20th century, including the Système Hydrologique Européen (SHE) model (Abbott et al., 1986), the European Soil Erosion Model (EUROSEM) (Morgan et al., 1998a), the Limburg Soil Erosion Model (LISEM) (de Roo et al., 1996), and the soil erosion model for Mediterranean regions (SEMMED) (de Jong et al., 1999). Rose et al. (1983) developed an early mathematical model in Australia that described runoff on a plane assuming kin- ematic flow. All of the models discussed here were created to model erosion by water. In many cases these models were developed to address shortcomings in USDA models such as RUSLE and WEPP. For example, SHE was developed to address limitations in the ability of other models to evaluate things such as the impact of anthropogenic activities on land use change and water quality (Abbott et al., 1986). Some of the driving forces behind developing EUROSEM included that RUSLE could not pre- dict deposition, the pathways taken by eroded material, or provide erosion information for individual rainfall events. Also, WEPP could not model peak sediment discharge or the pat- tern of sediment discharge over time (Morgan et al., 1998a). LISEM was incorporated into a raster-based GIS, which allowed the inclu- sion of remotely sensed data and was seen as being user friendly (de Roo et al., 1996). In other cases, such as SEMMED (de Jong et al., 1999), the model was developed to address the conditions within a specific environmental setting. Some of these models also saw wide- spread use; Morgan et al. (1998b) reported on the growing use of EUROSEM beyond Europe. Based on citation numbers in Google Scholar the SHE and EUROSEM models appear to be the most used of the 20th century water erosion models developed outside of the United States, with LISEM also getting a good amount of use. Soil erosion models can tell how rapidly soil is lost given a set of conditions, but to deter- mine if the rate of soil loss is a problem it is also important to know how rapidly pedo- genesis might replace that lost soil. Several studies that investigated rates of soil forma- tion were conducted during the 20th century; a number of those studies are summarized in Brevik (2013). These studies indicated that soil formation rates are often only fractions of a mm year−1 . However, the studies available are also heavily slanted to the United States and Europe. More studies covering wider geo- graphic ranges are needed, especially in areas that are highly vulnerable to soil and land degradation. Concept of Soil Quality/Health The terms soil quality and soil health are generally used interchangeably within the scientific literature and are functionally syn- onymous, with scientists often preferring the term soil quality and farmers preferring soil health (Harris and Bezdicek, 1994; Karlen et al., 1997). However, the scientific commu- nity is increasingly using the term soil health as it implies a connection with soil biology, which is becoming a larger focal point in soils studies. Western culture has often viewed soil in a negative way, with terms such as “dirt- poor,” “soiled,” and “dirty minded” being common in the English language (Henry and Cring, 2013). Erosion of soils (Lieskovský and Kenderessy, 2014) and land management prac- tices commonly used during the 20th century (Miao et al., 2015) often led to large-scale land degradation. The overall cultural underap- preciation of soil and degradation caused by management practices was a driving force behind development of the soil quality/health concept (Karlen et al., 1997; Schjønning et al., 2004). Accurate soil maps and the information they contain are critical to fully understanding soil quality/health issues (Norfleet et al., 2003; Melakeberhan and Avendaño, 2008; Sanchez et al., 2009). However, existing soil maps are rarely detailed enough to adequately inform
- 26. Developments in the 20th Century I. THEORY 17 such decisions at the field or finer scale. The availability of larger scale maps may be useful to aid in tackling these problems. The soil quality/health concept is closely tied to studies on the influence of soils on human health (Karlen et al., 1997; Schjønning et al., 2004). The relationship between soils and human health is another area that received increasing attention during the 20th century. Healthy soils influence human health by pro- ducing food products to support a balanced diet, providing a balanced supply of essen- tial nutrients, filtering contaminants from water supplies, and as a source of medicines. However, unhealthy soils may act as possible points of contact with a variety of chemicals and pathogens that can negatively influence human health (Brevik, 2009). There are several ways that soil mapping can assist in under- standing threats and improving human health. Some of these are quite traditional, for exam- ple, soil maps have long been used to provide information in support of agronomic manage- ment decisions related to crop production (Rust and Hanson, 1975; Karlen et al., 1990; Reynolds et al., 2000). Soil maps have also been an impor- tant component of water quality (Zhang et al., 1997; Chaplot, 2005) and soil contamination (Wu et al., 2002) assessment. Other uses of soil maps to support human health are less tradi- tional. Some soil organisms are human patho- gens, and a knowledge of soil properties and their distribution can help to create models to determine populations that are at risk of expo- sure to certain diseases (Tabor et al., 2011). Appropriate zoning policies that promote appropriate land uses based on information available in soil maps can also support public health (Neff et al., 2013). Therefore soil maps have had a role in supporting human health for many years and have the potential to have an enhanced role in the future as those maps become more quantitative and informative, while our understanding of some of these more complex environmental relationships improves. Global Positioning Systems and Geographic Information Systems Advances such as remote and proximal sens- ing were of limited practical use in support of soil mapping until ways were developed to precisely locate, manage, and manipulate the information contained within large data sets. GPS provided the means to precisely locate where the data were observed, and GIS pro- grams run on rapidly improving computer technology provided the means to manage, manipulate, model, and analyze ever increasing amounts of spatial data. The first publically available GPS was devel- oped by the US military in the 1970s, however, signal accuracy was degraded so that inaccura- cies of up to 500m would occur (Hannay, 2009). That meant early GPS systems were of limited use to soil scientists. Signal degradation was reduced to 100m in 1983 and was removed in 2000 (Hannay, 2009). As signal degradation was reduced the applicability of GPS for use in soil studies increased. The ability to precisely locate the position that data points were col- lected from revolutionized soil mapping and modeling, as sample sites could be accurately revisited to track trends over time, spatial rela- tionships could be accurately intersected and investigated, and spatial statistical techniques could be used more effectively to model soil properties in-between sampling points. GPS was able to rapidly and inexpensively provide location information for data that could then be fed into a GIS. The idea of laying multiple maps on top of one another to investigate the spatial relation- ships between related objects is not new; soil scientists have done so since the second half of the 19th century (Marbut, 1951). However, overlying multiple maps on top of one another could rapidly create an abundance of informa- tion that was difficult to effectively analyze visually and understand (Aguirre, 2014). The desire to be able to analyze the relationship
- 27. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 18 between multiple spatial variables was a moti- vating factor behind proposing the first GIS in the 1960s (Tomlinson, 1962). The develop- ment of both commercially available and open source GIS programs through the latter part of the 20th century greatly enhanced the ability to quantitatively analyze spatial relationships between the items depicted in various maps of separate, but possibility related, natural features. GIS also altered the concepts of map scale. Prior to the advent of GIS the level of detail that could be shown on a map was essentially determined by the size of the paper the map would be printed on and the amount of area the map would cover. In other words a map of an entire country printed on a small piece of paper could not show much detail for the item (e.g., soil) being mapped (Fig. 1.2), while a map on the same sized piece of paper that only covered a few square km could show much more detail for the same mapped item (Fig. 1.2). However, digital maps created with GIS can show multiple levels of detail, as the same GIS-based map can be zoomed out to show an entire country or zoomed in to show just a few square km within that country, all using the same data-base but with different levels of mapping detail displayed based on the level of zoom. By the end of the 20th century the combination of GPS and GIS allowed spatial analyses of soil properties and attributes and modeling of soil relationships and processes rapidly and inexpensively at a level of detail that had never before been possible. Remote and Proximal Sensing Remote sensing refers to a wide range of technologies used to detect Earth’s surface, usually using aerial or satellite platforms. The earliest use of remote sensing in soil science was the development of aerial photographs as base maps for soil survey in the United States in the 1920s and 1930s (Bushnell, 1929), which represented a major advance over creating base maps using plane tables and odometers (Worthen, 1909) or using topographic maps when they were available as was common prior to the use of aerial photography (Miller and Schaetzl, 2014). Digital remote sensing information was made widely available in the 1970s when the United States launched the Landsat program, one of the most popular sources of data for digital soil mapping. Seven Landsat satellites were launched during the 20th century with progressively increasing resolution and capa- bilities (Table 1.3). Another remote sensing technique developed in the 20th century that is seeing increasing use in modern soil science is LiDAR (McBratney et al., 2003; Brubaker et al., 2013). Aerial laser profiling systems date back to the 1970s, but it took advances in GPS, iner- tial measurement units, and inertial navigation systems to make LiDAR practical, something that did not occur until the mid-1990s (Carson et al., 2004). LiDAR represented an increase in data density and resolution of more than two orders of magnitude over traditional topo- graphic information, significantly enhancing the ability of scientists to study landscapes, improving preplanning for field work and sam- pling (Roering et al., 2013), and making LiDAR an invaluable information layer in GIS-based analyses (Fisher et al., 2005). Satellite- and airplane-based radar technologies and airborne gamma-ray spectrometry are additional remote sensing techniques that were available in the late 20th century that have been used to aid in soil mapping (McBratney et al., 2003). Because remote sensing data are collected from aerial or satellite platforms, the sensors can quickly col- lect information over large areas. One limitation of remote sensing is that it is largely confined to sensing conditions at the Earth’s surface, with limited depth of pen- etration. Proximal sensing techniques have the ability to probe deeper into the soil profile, but are not able to cover large areas as quickly
- 28. Developments in the 20th Century I. THEORY 19 TABLE 1.3 History of the Landsat Satellites Launched Prior to 2000 Satellite Operational Dates Notes Landsat 1 July 1972–January 1978 Two sensors with 80m ground resolution. Sensor 1—Return Beam Vidicon (RBV) with three bands: 1—visible blue-green (475–575nm), 2—visible orange-red (580–680nm), and 3—visible red to near-infrared (690–830nm). Sensor 2—multispectral scanner (MSS) with four bands: 4—visible green (0.5–0.6µm), 5—visible red (0.6–0.7µm), 6—near- infrared (0.7–0.8µm), and 7—near-infrared (0.8–1.1µm). Ground sampling interval (pixel size): 57 × 79m. Scene size: 170km × 185km Landsat 2 January 1975–July 1983 Two sensors with 80m ground resolution. Sensor 1—RBV with three bands. Sensor 2—MSS with four bands. Ground sampling interval (pixel size): 57 × 79m. Scene size: 170km × 185km Landsat 3 March 1978–September 1983 Two sensors with 40m ground resolution. Sensor 1—RBV with three bands. Sensor 2—MSS with five bands: 4—visible green (0.5–0.6µm), 5—visible red (0.6–0.7µm), 6—near-infrared (0.7–0.8µm), 7—near- infrared (0.8–1.1µm), 8—thermal (10.4–12.6µm). Ground sampling interval (pixel size): 57 × 79m. Scene size: 170km × 185km Landsat 4 July 1982–December 1993 Two sensors. Sensor 1—MSS with four bands: 4—visible green (0.5–0.6µm), 5—visible red (0.6–0.7µm), 6—near-infrared (0.7–0.8µm), 7—near-infrared (0.8–1.1µm). Ground sampling interval (pixel size): 57 × 79m. Sensor 2—thematic mapper (TM) with seven bands: 1—visible (0.45–0.52µm), 2—visible (0.52–0.60µm), 3—visible (0.63–0.69µm), 4— near-infrared (0.76–0.90µm), 5—near-infrared (1.55–1.75µm), 6—thermal (10.40–12.50µm), 7—mid-infrared (IR) (2.08–2.35µm). Ground sampling interval (pixel size): 30m reflective, 120m thermal. Scene size: 170km × 185km Landsat 5 March 1984–January 2013 Two sensors. Sensor 1—MSS with four bands: 4—visible green (0.5–0.6µm), 5—visible red (0.6–0.7µm), 6—near-infrared (0.7–0.8µm), 7—near-infrared (0.8–1.1µm). Ground sampling interval (pixel size): 57 × 79m. Sensor 2—thematic mapper (TM) with seven bands: 1—visible (0.45–0.52µm), 2—visible (0.52–0.60µm), 3—visible (0.63–0.69µm), 4— near-infrared (0.76–0.90µm), 5—near-infrared (1.55–1.75µm), 6—thermal (10.40–12.50µm), 7—mid-infrared (IR) (2.08–2.35µm). Ground sampling interval (pixel size): 30m reflective, 120m thermal. Scene size: 170km × 185km Landsat 6 October 1993 Failed to achieve orbit Landsat 7 April 1999–present One sensor, Enhanced Thematic Mapper Plus (ETM+) with eight bands: 1—visible (0.45–0.52µm), 2—visible (0.52–0.60µm), 3—visible (0.63– 0.69µm), 4—near-infrared (0.77–0.90µm), 5—near-infrared (1.55–1.75µm), 6—thermal (10.40–12.50µm), low gain/high gain, 7—mid-infrared (2.08–2.35µm), 8—panchromatic (PAN) (0.52–0.90µm). Ground sampling interval (pixel size): 30m reflective, 60m thermal, 15m panchromatic. Scene size: 170km × 185km Source: USGS, 2015. Landsat missions: imaging the Earth since 1972. <http://landsat.usgs.gov/about_mission_history.php> (accessed 19.01.16).
- 29. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 20 as remote sensing. Several different proximal sensing technologies were experimented within the 20th century to investigate their poten- tial application to soil work (Adamchuk et al., 2015), but the two that received the most atten- tion were electromagnetic induction (EMI) and ground-penetrating radar (GPR) (Allred et al., 2008, 2010). EMI was originally used to assess soil salin- ity (de Jong et al., 1979; Rhoades and Corwin, 1981; van der Lelij, 1983; Williams and Baker, 1982), but uses rapidly spread to other areas including measuring soil water content (Kachanoski et al., 1988; Khakural et al., 1998; Sheets and Hendrickx, 1995), clay content (Williams and Hoey, 1987), compaction (Brevik and Fenton, 2004), and exchangeable Ca and Mg (McBride et al., 1990). Each of these soil properties or attributes could be mapped with a great deal of spatial resolution using a geo- referenced EMI survey if strong relationships could be found between the property or attrib- ute of interest and the apparent electrical con- ductivity (ECa) readings provided by the EMI instrument. Because of its ability to be linked to a GPS receiver and be correlated to a wide range of soil properties and attributes, EMI also attracted attention as a soil mapping tool start- ing in the 1990s (Jaynes et al., 1993, Doolittle et al., 1994; 1996; Fenton and Lauterbach, 1999). However, drawbacks to EMI surveys include that the ECa-soil property/attribute relation- ships had to be established for each location, they were not universal, and changes in tran- sient soil properties like soil water content and temperature change the absolute values (Brevik et al., 2004; Brevik et al., 2006) and, in some cases, the relative values (Brevik et al., 2006) of EMI readings over time even at a given location. GPR was also used for the first time in soil studies in the 1970s (Benson and Glaccum, 1979; Johnson et al., 1979). GPR was success- fully used to investigate several soil properties and attributes, including lateral extent of soil horizons and pans, depth to bedrock and water tables, and determine soil texture, organic matter content, and degree of cementation. However, many soils were found to be unsuit- able for GPR investigations, including those with high soluble salt, clay, and water contents (Doolittle et al., 2007). Therefore use of GPR was limited to soils with favorable properties (Fig. 1.5) (Annan, 2002). Remote and proximal sensing have both became important ways to rapidly collect large amounts of spatial data that can be related to soil properties and attributes. Analyzing and mapping the data collected with such tech- niques provided considerable information about the spatial distribution of soil proper- ties and attributes that could then be entered into models (Brevik et al., 2016). In addition, the data could be collected at a much lower cost than with traditional field soil survey tech- niques (McBratney et al., 2000). Spatial Statistics and Other Numerical Techniques Research into the application of mathemati- cal methods to study soil mapping and gene- sis issues, an approach that came to be called pedometrics, began in the 1980s (Minasny and McBratney, 2016). A number of different spa- tial statistics and other numerical techniques were being utilized to analyze and model the spatial variation of soil properties and attrib- utes by the end of the 20th century (McBratney et al., 2000). While many of these techniques, such as kriging (Krige, 1951) and indices and models of diversity (e.g., Simpson, 1949; Margalef, 1958) have been around for dec- ades, they were developed to address issues in other disciplines. Kriging was originally applied to the evaluation of ores and their distribution by the mining industry (Krige, 1951) and diversity approaches were widely used in ecological studies (Ibáñez et al., 2005). These techniques were applied to soil science
- 30. Concluding Comments I. THEORY 21 questions in the final 20 years of the 20th cen- tury and were proven to be useful to soil sci- entists to model spatial distribution of soil properties, attributes, and pedodiversity, with several different variations of both techniques available (McBratney et al., 2000; Ibáñez et al., 2005). Cokriging, where the covariance with more readily observed variables were used to inform spatial predictions, proved particu- larly useful to soil scientists (McBratney et al., 2000; Minasny and McBratney, 2016) because it increased the accuracy of predictions. Another mathematical innovation was fuzzy sets and fuzzy logic, which were applied to soil clas- sification (De Gruijter and McBratney, 1988) and soil survey (McBratney et al., 2000). Fuzzy applications are well suited to soil science because they allow continuous determination of the degree of soil class membership, much as occurs in a natural soil system. Increased computing power and the ability to precisely locate and manipulate the data in large data sets together with new mathematical tech- niques allowed for a revolution in the analysis of spatial data, and soil scientists took advan- tage of these new opportunities. CONCLUDING COMMENTS Soil science had come a long way by the end of the 20th century. The trial and error FIGURE 1.5 The GPR soil suitability map for the conterminous United States. Areas in dark green have soils most suit- able to exploration using GPR, while areas in purple are least suitable (Soil Survey Staff, 2009). Source: Figure courtesy of USDA-NRCS.
- 31. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 22 approaches the earliest agricultural socie- ties used to determine which soils would best support their crops had been replaced by geo- referenced soil data and predictive interpreta- tions that were being analyzed and modeled in high-powered computer systems using a variety of mathematical and statistical tech- niques. Despite that, there were still significant needs to move soil survey forward and allow the information collected and displayed on maps to become more useful to a wider range of end users. There was a continued need for increased quantification of soil survey informa- tion, standardization in the communication of information, and ready access to up-to-date soil survey information from practically any loca- tion (Beaudette and O’Geen, 2010). There were still soil properties and processes that were not well understood and not well incorporated into pedologic models. For example, the influ- ence of aspect and vegetation type, altitudinal gradient, and soil sampling type needed to be better understood, and these limitations meant that pedologic models still needed considerable additional work. There was a trend towards less field work in soil science at the end of the 20th century, with more reliance on remote and proximal sensing techniques. Remote and proximal sensing provides a great abundance of very valuable data at less expense than tradi- tional field work, but field work is still essential to calibrate remote and proximal sensing data. Therefore it is important that funding continue to be provided for such work. Furthermore, there are many end users of the products created by modern soil mapping and modeling. It is critical that soil scientists work with other scientists and with other stakehold- ers, such as land managers, policy makers, and the general public, to ensure that the final map- ping and modeling products are useful, usable, and understandable to a wide range of end users (Bouma, 2015). Soil maps and models have been used to assist in making a number of manage- ment decisions, including agricultural, forestry, urban, and environmental decisions, often made by nonscientists. Accurate soil maps and models are critical to sustainable management of Earth’s resources as we move into the future. Acknowledgements E.C. Brevik was partially supported by the National Science Foundation under Grant Number IIA-1355466 during this project. References Abbott, M.B., Bathurst, J.C., Cunge, J.A., O’Connell, P.E., Rasmussen, J., 1986. An introduction to the European Hydrological System-Systeme Hydrologique Europeen, “SHE”, 1: History and philosophy of a phys- ically-based, distributed modelling system. J. Hydrol. 87 (1–2), 45–59. Adamchuk, V.I., Allred, B., Doolittle, J., Grote, K., Viscarra Rossel, R.A., 2015. Tools for proximal soil sensing. In: Ditzler, C., West, L. (Eds.), Soil Survey Manual, Soil Survey Staff. Natural Resources Conservation Service, Washington, DC. U.S. Department of Agriculture Handbook 18. Available from: http:// www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ scientists/?cid=nrcseprd329418 (accessed 20.01.16). Aguirre, J.C., 2014. The unlikely history of the origins of modern maps. Smithsonian Magazine. http://www. smithsonianmag.com/history/unlikely-history-origins- modern-maps-180951617/?no-ist (accessed 24.01.16). Aldrich, M.L., 1979. American state geological surveys, 1820–1845. In: Schneer, C.J. (Ed.), Two Hundred Years of Geology in America. Univ. Press of New England, Hanover, NH, pp. 133–143. Allred, B.J., Ehsani, M.R., Daniels, J.J., 2008. General consid- erations for geophysical methods applied to agricul- ture. In: Allred, B.J., Daniels, J.J., Ehsani, M.R. (Eds.), Handbook of Agricultural Geophysics. CRC Press, Taylor & Francis, Boca Raton, FL, pp. 3–16. Allred, B.J., Freeland, R.S., Farahani, H.J., Collins, M.E., 2010. Agricultural geophysics: past, present, and future. In: Proceedings of the Symposium on the Application of Geophysics to Engineering and Environmental Problems, SAGEEP 2010, pp. 190–202. Annan, A.P., 2002. GPR-history, trends, and future develop- ments. Subsurf. Sens. Technol. Appl. 3 (4), 253–270. Bašić, F., 2005. Soil resources of Croatia. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 89–96.
- 32. I. THEORY 23 REFERENCES Beaudette, D.E., O’Geen, A.T., 2010. An iPhone application for on-demand access to digital soil survey informa- tion. Soil Sci. Soc. Am. J. 74 (5), 1682–1684. Benson, R., Glaccum, R., 1979. The Application of Ground Penetrating Radar to Soil Surveying. Final Report. NASA, Cape Kennedy Space Center, FL. Blum, W.E.H., 1998. Agriculture in a sustainable environ- ment—a holistic approach. Int. Agrophys. 12, 13–24. Boardman, J., Poesen, J., Evans, R., 2003. Socio-economic factors in soil erosion and conservation. Environ. Sci. Policy 6, 1–6. Boni, I., Giovannozzi, M., Martalò, P.F., Mensio, F., 2015. Soil erosion assessment in Piedmont: a territorial approach under the rural development program. In: Proceedings 8th European Congress on Regional Geoscientic Cartography and Information Systems. Barcelona Spain, 15–17 June, pp. 183–184. Bonnard, L.F., 2005. Soil survey in Switzerland. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 365–370. Bouma, J., 2015. Engaging soil science in transdisciplinary research facing “wicked” problems in the information society. Soil Sci. Soc. Am. J. 79, 454–458. Brevik, E.C., 2009. Soil, food security, and human health. In: Verheye, W. (Ed.), Soils, Plant Growth and Crop Production. EOLSS Publishers, Oxford, UK. Encyclopedia of Life Support Systems (EOLSS), Developed under the Auspices of the UNESCO. http://www.eolss.net. (accessed 21.01.16). Brevik, E.C., 2013. Forty years of soil formation in a South Georgia, USA borrow pit. Soil Horizons 54 (1), 20–29. http://dx.doi.org/10.2136/sh12-08-0025. Brevik, E.C., Calzolari, C., Miller, B.A., Pereira, P., Kabala, C., Baumgarten, A., et al., 2016. Soil mapping, classi- fication, and modeling: history and future directions. Geoderma 264, 256–274. http://dx.doi.org/10.1016/j. geoderma.2015.05.017. Brevik, E.C., Fenton, T.E., 2004. The effect of changes in bulk density on soil electrical conductivity as meas- ured with the Geonics® EM-38. Soil Surv. Horizons 45 (3), 96–102. Brevik, E.C., Fenton, T.E., Homburg, J.A., 2015. Historical highlights in American soil science—prehistory to the 1970s. Catena. http://dx.doi.org/10.1016/j. catena.2015.10.003. Brevik, E.C., Fenton, T.E., Horton, R., 2004. Effect of daily soil temperature fluctuations on soil electrical conduc- tivity as measured with the Geonics® EM-38. Precis. Agric. 5, 143–150. Brevik, E.C., Fenton, T.E., Lazari, A., 2006. Soil electrical conductivity as a function of soil water content and implications for soil mapping. Precis. Agric. 7, 393–404. Brevik, E.C., Hartemink, A.E., 2010. Early soil knowledge and the birth and development of soil science. Catena 83, 23–33. Brubaker, K.M., Myers, W.L., Drohan, P.J., Miller, D.A., Boyer, E.W., 2013. The use of LiDAR terrain data in characterizing surface roughness and micro- topography. Appl. Environ. Soil Sci. http://dx.doi. org/10.1155/2013/891534. Bushnell, T.M., 1929. Aerial photography and soil survey. Am. Soil Survey. Assoc. Bull. B10, 23–28. http://dx.doi. org/10.2136/sssaj1929.036159950B1020010004x. Butler, B.W., 1950. A theory of prior streams as a casual fac- tor of soil occurrence in the Riverine Plain of south- eastern Australia. Crop Pasture Sci. 1 (3), 231–252. Carson, W.W., Andersen, H.E., Reutebuch, S.E., McGaughey, R.J., 2004. LiDAR applications in forestry—an overview. ASPRS Annual Conference Proceedings, pp. 1–9. Cerdan, O., Govers, G., Le Bissonnais, Y., Van Oost, K., Poesen, J., Saby, N., et al., 2010. Rates and spatial vari- ations of soil erosion in Europe: a study based on ero- sion plot data. Geomorphology 122, 167–177. Chaplot, V., 2005. Impact of DEM mesh size and soil map scale on SWAT runoff, sediment, and NO3–N loads predictions. J. Hydrol. 312, 207–222. Cline, M.G., 1977. The soils we classify and the soils we map. In: New York Soil Survey Conference, Bergamo East. USDA-SCS, U.S. Gov. Print Office, Washington, DC, pp. 5–19. Coleman, K., Jenkinson, D.S., 1996. RothC-26.3-A model for the turnover of carbon in soil Evaluation of Soil Organic Matter Models. Springer, Berlin. 237–246. Columela, L.J.M., 42 CE. De Res Rustica. Siglo I dC Los doce libros de Agricultura. Barcelona, Spain: Editorial Iberia (reprinted in 1979). Cooper, D., Foster, C., Goodey, R., Hallett, P., Hobbs, P., Irvine, B., et al., 2010. Use of ‘UKCIP08 Scenarios’ to Determine the Potential Impact of Climate Change on the Pressures/Threats to Soils in England and Wales. Final Report to Defra, Project SP0571. De Gruijter, J.J., McBratney, A.B., 1988. A modified fuzzy k-means method for predictive classification. In: Bock, H.H. (Ed.), Classification and Related Methods of Data Analysis. Elsevier, Amsterdam, pp. 97–104. de Herrera, A., 1513. Agricultura General. Ministerio de Agricultura, Pesca y Alimentación, Madrid, (reprinted in 1981). de Jong, E., Ballantyne, A.K., Cameron, D.R., Read, D.L., 1979. Measurement of apparent electrical conductivity of soils by an electromagnetic induction probe to aid salinity surveys. Soil Sci. Soc. Am. J. 43, 810–812. de Jong, S.M., Paracchini, M.L., Bertolo, F., Folving, S., Megier, J., de Roo, A.P.J., 1999. Regional assessment of soil erosion using the distributed model SEMMED and remotely sensed data. Catena 37, 291–308.
- 33. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 24 De la Rosa, D., 2008. Evaluacion agro-ecologica de sue- los para el densarrollo rural sostenible. Eds. Mundi- Prensa, Madrid. ISBN:9788484763611. De la Rosa, D., 2013. Una agricultura a la medida de cada suelo: desde el conocimiento científico y la experiencia práctica a los sistemas de ayuda a la decisión. Inaugural speech at the Academy of Sciences in Sevilla, Spain. http://digital.csic.es/bitstream/10261/77729/1/ Una%20agricultura%20a%20la%20medida%20de%20 cada%20suelo.pdf (accessed 29.02.16). De la Rosa, D., Mayol, F., Diaz-Pereira, E., Fernández, M., De la Rosa Jr, D., 2004. A land evaluation decision sup- port system (MicroLEIS DSS) for agricultural soil pro- tection: with special reference to the Mediterranean region. Environ. Modell. Softw. 19, 929–942. de Roo, A.P.J., Wesseling, C.G., Ritsema, C.J., 1996. LISEM: a single-event physically based hydrological and soil erosion model for drainage basins. I: theory, input and output. Hydrol. Process. 10 (8), 1107–1117. Diamond, J., 2005. Collapse: How Societies Choose to Fail or Succeed. Penguin Books, New York. Dokuchaev, V.V., 1883. Russian Chernozem: Selected Works of V.V. Dokuchaev, vol. I. Israel Program for Scientific Translations, Jerusalem (translated in 1967). Doolittle, J.A., Minzenmayer, F.E., Waltman, S.W., Benham, E.C., Tuttle, J.W., Peaslee, S.D., 2007. Ground- penetrating radar soil suitability map of the contermi- nous United States. Geoderma 141, 416–421. Doolittle, J., Murphy, R., Parks, G., Warner, J., 1996. Electromagnetic induction investigations of a soil delin- eation in Reno County, Kansas. Soil Surv. Horizons 37, 11–20. Doolittle, J.A., Sudduth, K.A., Kitchen, N.R., Indorante, S.J., 1994. Estimating depth to claypans using electromag- netic inductive methods. J. Soil Water Conserv. 49 (6), 552–555. Dregne, H.E., 1995. Erosion and soil productivity in Australia and New Zealand. Land Degrad. Rehabil. 6, 71–78. Dudal, R., Deckers, J., Van Orshoven, J., Van Ranst, E., 2005. Soil survey in Belgium and its applications. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 63–71. Eckelmann, W., 2005. Soil information for Germany: the 2004 position. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 147–157. Eswaran, H., Reich, P.F., Padmanabhan, E., 2001. Challenges of managing the land resources of Asia. In: Issues in the Management of Agricultural Resources. Proceedings of a Seminar in Commemoration of FFTC’s 30th Anniversary, National Taiwan University, Taipei, Taiwan ROC, 6–8 September 2000. Food and Fertilizer Technology Center for the Asian and Pacific Region, pp. 85–104. Falloon, P.D., Smith, P., Smith, J.U., Szabó, J., Coleman, K., Marshall, S., 1998. Regional estimates of carbon seques- tration potential: linking the Rothamsted carbon model to GIS databases. Biol. Fertil. Soils 27, 236–241. Feller, C., Brown, G.G., Blanchart, E., Deleporte, P., Chernyanskii, S.S., 2003b. Charles Darwin, earthworms and the natural sciences: various lessons from past to future. Agric. Ecosyst. Environ. 99, 29–49. Feller, C., Thuriès, L.J.-M., Manlay, R.J., Robin, P., Frossard, E., 2003a. “The principles of rational agriculture” by Albrecht Daniel Thaer (1752–1828). An approach to the sustainability of cropping systems at the beginning of the 19th century. J. Plant Nutr. Soil Sci. 166, 687–698. Fenton, T.E., Lauterbach, M.A., 1999. Soil map unit com- position and scale of mapping related to interpreta- tions for precision soil and crop management in Iowa Proceeding of the 4th International Conference on Precision Agriculture. American Society of Agronomy, Madison, WI, pp. 239–251. Fisher, R.F., Fox, T.R., Harrison, R.B., Terry, T., 2005. Forest soils education and research: trends, needs, and wild ideas. Forest Ecol. Manage. 220, 1–16. Flanagan, D.C., Gilley, J.E., Franti, T.G., 2007. Water erosion prediction project (WEPP): development history, model capabilities, and future enhancements. Trans. ASABE 50 (5), 1603–1612. Free, E.E., 1911. The Movement of Soil Material by the Wind. U.S. Government Printing Office, Washington D.C., USDA Bureau of Soils Bulletin No. 68. Fullen, M.A., 2003. Soil erosion and conservation in north- ern Europe. Prog. Phys. Geogr. 27 (3), 331–358. Garrett, G., 1998. Partisan Politics in the Global Economy. Cambridge University Press, New York. Gerrard, A.J., 1992. Soil Geomorphology. Springer Science & Business Media, Berlin. Gonçalves, M.C., Reis, L.C.L., Pereira, M.V., 2005. Progress of soil survey in Portugal. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 275–279. Gong, Z., Zhang, X., Chen, J., Zhang, G., 2003. Origin and development of soil science in ancient China. Geoderma 115, 3–13. Hannay, P., 2009. Satellite navigation forensics techniques. Proceedings of the 7th Australian Digital Forensics Conference, 14–18.
- 34. I. THEORY 25 REFERENCES Hansen, Z.K., Libecap, G.D., 2004. Small farms, externali- ties, and the Dust Bowl of the 1930s. J. Polit. Econ. 112 (3), 665–694. Harris, R.F., Bezdicek, D.F., 1994. Descriptive aspects of soil quality/health. In: Defining Soil Quality for a Sustainable Environment, SSSA Special Publication No. 35. SSSA, Madison, WI, pp. 23–35. Hartemink, A.E., McBratney, A.B., 2008. A soil science renaissance. Geoderma 148, 123–129. Haslmayr, H.P., Geitner, C., Sutor, G., Knoll, A., Baumgarten, A., 2016. Soil function evaluation in Austria-development, concepts and examples. Geoderma 264, 379–387. Helms, D., 2008. Hugh Hammond Bennett and the Creation of the Soil Erosion Service. USDA-NRCS Historical Insights Number 8, pp. 1–13. Helms, D., 2010. Hugh Hammond Bennett and the creation of the Soil Conservation Service. J. Soil Water Conserv. 65 (2), 37A–47A. Hempel, J., Micheli, E., Owens, P., McBratney, A., 2013. Universal soil classification system report from the International Union of Soil Sciences Working Group. Soil Horizons 54 (2), 1–6. Henry, J.M., Cring, F.D., 2013. Geophagy: an anthropologi- cal perspective. In: Brevik, E.C., Burgess, L.C. (Eds.), Soils and Human Health. CRC Press, Boca Raton, pp. 179–198. Hilgard, E.W., 1860. Report on the Geology and Agriculture of the State of Mississippi. State Printer, Jackson, MS. Hillel, D., 1991. Out of the Earth: Civilization and the Life of the Soil. University of California Press, Berkeley, CA. Holland, J.M., 2004. The environmental consequences of adopting conservation tillage in Europe: reviewing the evidence. Agric. Ecosyst. Environ. 103, 1–25. Holliday, V.T., 2006. In: Warkentin, B.P. (Ed.), A history of soil geomorphology in the United States. Elsevier, Amsterdam, pp. 187–254. Hudson, B.D., 1999. Some interesting historical facts about the American soil survey. Soil Surv. Horizons 40, 21–26. Ibáñez, J.J., De-Alba, S., Bermúdez, F.F., García-Álvarez, A., 1995. Pedodiversity: concepts and measures. Catena 24, 215–232. Indorante, S.J., McLeese, R.L., Hammer, R.D., Thompson, B.W., Alexander, D.L., 1996. Positioning soil survey for the 21st century. J. Soil Water Conserv. 51, 21–28. Jaynes, D.B., Colvin, T.S., Ambuel, J., 1993. Soil type and crop yields determination from ground conductivity surveys. In: 1993 International Meeting of American Society of Agricultural Engineers. Paper No. 933552. American Society of Agricultural Engineers, St. Joseph, Michigan. Jenny, H., 1941. Factors of Soil Formation: A System of Quantitative Pedology. Dover Publications, Mineola, NY, (reprinted in 1994). Jenny, H., 1961. E.W. Hilgard and the Birth of Modern Soil Science. Collana della Revisa Agrochemical, Pisa. Jensen, C.T., Moriarty, M.D., Johnson, K.D., Terry, R.E., Emery, K.F., Nelson, S.D., 2007. Soil resources of the Motul De San José Maya: correlating Soil Taxonomy and modern Itzá Maya soil classification within a classic Maya archaeological zone. Geoarchaeology 22 (3), 337–357. Johnson, R.W., Glaccum, R., Wojtasinski, R., 1979. Application of ground penetrating radar to soil survey. Proc. Soil Crop Soc. Florida 39, 68–72. Jones, R., 1997. Soil Survey of Emmet County, Iowa. Natural Resources Conservation Service. U.S. Department of Agriculture. Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), 2005. Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy. Kachanoski, R.G., Gregorich, E.G., vanWesenbeeck, I.J., 1988. Estimating spatial variations of soil water content using noncontacting electromagnetic inductive meth- ods. Can. J. Soil Sci. 68, 715–722. Kaphengst, T. 2014. Towards a definition of global sustain- able land use? A discussion on theory, concepts and implications for governance. Discussion paper pro- duced within the research project “GLOBALANDS – Global Land Use and Sustainability”. http://www. ecologic.eu/globalands/about. (accessed 14.08.16). Karlen, D.L., Mausbach, M.J., Doran, J.W., Cline, R.G., Harris, R.F., Schuman, G.E., 1997. Soil quality: a con- cept, definition, and framework for evaluation. Soil Sci. Soc. Am. J. 61, 4–10. Karlen, D.L., Sadler, E.J., Busscher, W.J., 1990. Crop yield variation associated with Coastal Plain soil map units. Soil Sci. Soc. Am. J. 54, 859–865. Khakural, B.R., Robert, P.C., Hugins, D.R., 1998. Use of non- contacting electromagnetic inductive method for esti- mating soil moisture across a landscape. Commun. Soil Sci. Plant Anal. 29 (11–14), 2055–2065. King, D., Stengel, P., Jamagne, M., Le Bas, C., Arrouays, D., 2005. Soil mapping and soil monitoring: state of progress and use in France. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, sec- ond ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 139–146. Kolchakov, I., Rousseva, S., Georgiev, B., Stoychev, D., 2005. Soil survey and soil mapping in Bulgaria. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 83–87. Krasilnikov, P., Ibáñez-Martí, J.J., Arnold, R., Shoba, S., 2009. A Handbook of Soil Terminology, Correlation, and Classification. Earthscan, London, UK.
- 35. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 26 Krige, D.G., 1951. A statistical approach to some basic mine valuation problems on the Witwatersrand. J. Chem. Metallur. Mining Soc. S. Afr. 52, 119–139. Krupenikov, I.A., 1992. History of Soil Science from its Inception to the Present. Oxonian Press, New Delhi. Langdale, G.W., Blevins, R.L., Karlen, D.L., McCool, D.K., Nearing, M.A., Skidmore, E.L., et al., 1991. Cover crop effects on soil erosion by wind and water Cover Crops for Clean Water. Soil and Water Conservation Society, Ankeny, IA, pp. 15–22. Lee, J., Coulter, B., 2005. Application of soils data to land use and environmental problems in Ireland. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 187–191. Lieskovský, J., Kenderessy, P., 2014. Modelling the effect of vegetation cover and different tillage practices on soil erosion in vineyards: a case study in Vráble (Slovakia) using WATEM/SEDEM. Land Degrad. Develop. 25, 288–296. Marbut, C.F., 1922. Soil classification. Am. Soil Surv. Assoc. Bull. B3, 24–33. Marbut, C.F., 1928. History of soil survey ideas. In: Weber, G.A. (Ed.), The Bureau of Chemistry and Soils: Its History, Activities, and Organization. Brookings Institution Institute for Government Research, Washington, DC, pp. 91–98. Marbut, C.F., 1951. Soils: their genesis and classification A Memorial Volume of Lectures Given in the Graduate School of the United States Department of Agriculture in 1928. Soil Science Society of America, Madison, WI. Margalef, R., 1958. Information theory in ecology. Gen. Syst. Bull. 3, 36–71. McBratney, A.B., Mendonça Santos, M.L., Minasny, B., 2003. On digital soil mapping. Geoderma 117, 3–52. McBratney, A.B., Odeh, I.O.A., Bishop, T.F.A., Dunbar, M.S., Shatar, T.M., 2000. An overview of pedometric tech- niques for use in soil survey. Geoderma 97, 293–327. McBride, R.A., Gordon, A.M., Shrive, S.C., 1990. Estimating forest soil quality from terrain measurements of appar- ent electrical conductivity. Soil Sci. Soc. Am. J. 54 (1), 290–293. McCracken, R.J., Helms, D., 1994. Soil surveys and maps. In: McDonald, P. (Ed.), The Literature of Soil Science. Cornell Univ. Press, Ithaca, pp. 275–311. McGee, W.J., 1911. Soil Erosion. Bureau of Soils Bulletin No. 71. U.S. Government Printing Office, Washington, DC. Melakeberhan, H., Avendaño, F., 2008. Spatio-temporal con- sideration of soil conditions and site-specific manage- ment of nematodes. Precis. Agric. 9, 341–354. Miao, L., Moore, J.C., Zeng, F., Lei, J., Ding, J., He, B., et al., 2015. Footprint of research in desertification manage- ment in China. Land Degrad. Develop. 26, 450–457. Miller, B.A., Schaetzl, R.J., 2014. The historical role of base maps in soil geography. Geoderma 230–231, 329–339. Milne, G., 1935. Some suggested units of classification and mapping particularly for East African soils. Soil Res. 4 (3), 183–198. Minasny, B., McBratney, A.B., 2016. Digital soil mapping: a brief history and some lessons. Geoderma 264, 301–311. Morgan, R.P.C., Quinton, J.N., Smith, R.E., Govers, G., Poesen, J.W.A., Auerswald, K., et al., 1998a. The European soil erosion model (EUROSEM): a dynamic approach for pre- dicting sediment transport from fields and small catch- ments. Earth Surf. Process. Landforms 23, 527–544. Morgan, R.P.C., Quinton, J.N., Smith, R.E., Govers, G., Poesen, J.W.A., Auerswald, K., et al., 1998b. The European Soil Erosion Model (EUROSEM): Documentation and User Guide, Version 3.6. Silsoe College, Cranfield University. Morgan, R.P.C., Rickson, R.J., 1990. Issues on soil erosion in Europe: the need for a soil conservation policy. In: Boardman, J., Foster, I.D.L., Dearing, J.A. (Eds.), Soil Erosion on Agricultural Land. John Wiley and Sons Ltd., Hoboken, pp. 591–603. Muir, J.W., 1962. The general principles of classification with reference to soils. J. Soil Sci. 13 (1), 22–30. Muñoz-Rojas, M., Jordán, A., Zavala, L.M., González- Peñaloza, F.A., De la Rosa, D., Pino-Mejias, R., et al., 2013. Modelling soil organic carbon stocks in global change scenarios: a CarboSOIL application. Biogeosciences 10, 8253–8268. Munteanu, I., Dumitru, M., Florea, N., Canarache, A., Lacatusu, R., Vlad, V., et al., 2005. Status of soil map- ping, monitoring, and database compilation in Romania at the beginning of the 21st century. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 281–296. Neff, R.A., Carmona, C., Kanter, R., 2013. Addressing soil impacts on public health: issues and recommendations. In: Brevik, E.C., Burgess, L.C. (Eds.), Soils and Human Health. CRC Press, Boca Raton, pp. 259–295. Němeček, J., Kozák, J., 2005. Status of soil surveys, inven- tory and soil monitoring in the Czech Republic. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 103–109. Nettleton, W.D., Lynn, W.C., 2008. Development in soil sur- vey: soil survey investigations laboratories’ support of taxonomic concepts. Soil Surv. Horizons 49, 48–51. Norfleet, M.L., Ditzler, C.A., Puckett, W.E., Grossman, R.B., Shaw, J.N., 2003. Soil quality and its relationship to pedology. Soil Sci. 168 (3), 149–155.
- 36. I. THEORY 27 REFERENCES Olson, K.R., Norton, L.D., Fenton, T.E., Lal, R., 1994. Quantification of soil loss from eroded soil phases. J. Soil Water Conserv. 49 (6), 591–596. Olsson, M., 2005. Soil survey in Sweden. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 357–363. Osterman, D.A., Hicks, T.L., 1988. Highly erodible land: farmer perceptions versus actual measurements. J. Soil Water Conserv. 43 (2), 177–182. Pal, I., Al-Tabbaa, A., 2009. Suitability of different erosiv- ity models used in RUSLE2 for the south west Indian region. Environmentalist 29, 405–410. Panagos, P., Borrelli, P., Poesen, J., Ballabio, C., Lugato, E., Meusburger, K., et al., 2015. The new assessment of soil loss by water erosion in Europe. Environ. Sci. Policy 54, 438–447. Parton, W.J., Schimel, D.S., Cole, C.V., Ojima, D.S., 1987. Analysis of factors controlling soil organic matter levels in Great Plains grasslands. Soil Sci. Soc. Am. J. 51, 1173–1179. Phillips, J.D., 1989. An evaluation of the state factor model of soil ecosystems. Ecol. Model. 45, 165–177. Pimentel, D., Harvey, C., Resosudarmo, P., Sinclair, K., Kurz, D., McNair, M., et al., 1995. Environmental and economic costs of soil erosion and conservation ben- efits. Science 267 (5201), 1117–1123. Pretty, J.N., Shah, P., 1997. Making soil and water conser- vation sustainable: from coercion and control to part- nerships and participation. Land Degrad. Develop. 8, 39–58. Reynolds, C.A., Jackson, T.J., Rawls, W.J., 2000. Estimating soil water-holding capacities by linking the Food and Agriculture Organization soil map of the world with global pedon databases and continuous pedotransfer functions. Water Resour. Res. 36 (12), 3653–3662. Rhoades, J.D., Corwin, D.L., 1981. Determining soil electri- cal conductivity-depth relations using an inductive electromagnetic soil conductivity meter. Soil Sci. Soc. Am. J. 45, 255–260. Roering, J.J., Mackey, B.H., Marshall, J.A., Sweeney, K.E., Deligne, N.I., Booth, A.M., et al., 2013. ‘You are HERE’: connecting the dots with airborne lidar for geomorphic fieldwork. Geomorphology 200, 172–183. Rose, C.W., Williams, J.R., Sander, G.C., Barry, D.A., 1983. A mathematical model of soil erosion and deposition pro- cesses: I. theory for a plane land element. Soil Sci. Soc. Am. J. 47, 991–995. Rust, R.H., Hanson, L.D., 1975. Crop Equivalent Rating Guide for Soils of Minnesota. Agricultural Experiment Station, University of Minnesota. Miscellaneous Report 132-1975. Sanchez, P.A., Ahamed, S., Carré, F., Hartemink, A.E., Hempel, J., Huising, J., et al., 2009. Digital soil map of the world. Science 325 (5941), 680–681. http://dx.doi. org/10.1126/science.1175084. Schaetzl, R., Anderson, S., 2005. Soils: Genesis and Geomorphology. Cambridge University Press, New York. Schjønning, P., Elmholt, S., Christensen, B.T., 2004. Soil quality management—concepts and terms. In: Schjønning, P., Elmholt, S., Christensen, B.T. (Eds.), Managing Soil Quality: Challenges in Modern Agriculture. CAB International, Wallingford, pp. 1–15. Sheets, K.R., Hendrickx, J.M.H., 1995. Noninvasive soil water content measurements using electromagnetic induction. Water Resour. Res. 31, 2401–2409. Simonson, R.W., 1959. Outline of a generalized theory of soil genesis. Soil Sci. Soc. Am. Proc. 23, 152–156. Simpson, E.H., 1949. Measurement of diversity. Nature 163, 688. Sippola, J., Yli-Halla, M., 2005. Status of soil mapping in Finland. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 133–138. Soil Survey Staff, 2009. Ground-penetrating radar soil suitability maps. <http://www.nrcs.usda.gov/wps/ portal/nrcs/detail/soils/survey/geo/?cid=nrcs142 p2_053622> (accessed 21.01.16). Sparks, D.L., 2006. Historical aspects of soil chemistry. In: Warkentin, B.P. (Ed.), Footprints in the Soil: People and Ideas in Soil History. Elsevier, Amsterdam, pp. 307–337. Stoate, C., Boatman, N.D., Borralho, R.J., Rio Carvalho, C., de Snoo, G.R., Eden, P., 2001. Ecological impacts of arable intensification in Europe. J. Environ. Manage. 63, 337–365. Tabor, J.A., O’Rourke, M.K., Lebowitz, M.D., Harris, R.B., 2011. Landscape-epidemiological study design to investigate an environmentally based disease. J. Exposure Sci. Environ. Epidemiol. 21, 197–211. Thompson, T.R.E., Bradley, R.I., Hollis, J.M., Bellamy, P.H., Dufour, M.J.D., 2005. Soil information and its appli- cation in the United Kingdom: an update. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 377–393. Tomlinson, R.F., 1962. An introduction to the use of elec- tronic computers in the storage, compilation and assess- ment of natural and economic data for the evaluation of marginal lands. National Land Capability Inventory Seminar, Agricultural Rehabilitation and Development Administration of the Canada Department of Agriculture, Ottawa, Canada. <https://gisandscience. files.wordpress.com/2012/08/4-computermapping. pdf> (accessed 24.01.16).
- 37. Chapter 1. HISTORICAL PERSPECTIVES I. THEORY 28 Troeh, F.R., Hobbs, J.A., Donahue, R.L., 2004. Soil and Water Conservation for Productivity and Environmental Protection, fourth ed. Prentice Hall, Upper Saddle River, NJ. US BLS, 2016. CPI inflation calculator. <http://www. bls.gov/data/inflation_calculator.htm> (accessed 17.01.16). US Census Bureau, 2016. U.S. and world population clock. <http://www.census.gov/popclock/> (accessed 25.01.16). USGS, 2015. Landsat missions: imaging the Earth since 1972. <http://landsat.usgs.gov/about_mission_his- tory.php> (accessed 19.01.16). van der Lelij, A., 1983. Use of Electromagnetic Induction Instrument (type EM-38) for Mapping Soil Salinity. Water Resources Commission, Murrumbidgee Division, New South Wales, Australia. van der Pouw, B.J.A., Finke, P.A., 2005. Development and perspective of soil survey in the Netherlands. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 245–255. Várallyay, G., 2005. Soil survey and soil monitoring in Hungary. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 169–179. Verheijen, F.G.A., Jones, R.J.A., Rickson, R.J., Smith, C.J., 2009. Tolerable versus actual soil erosion rates in Europe. Earth-Sci. Rev. 94, 23–38. von Liebig, J., 1840. Die organische Chemie in ihrer Anwendung auf Agrikultur und Physiologie. Vrščaj, B., Prus, T., Lobnik, F., 2005. Soil information and soil data use in Slovenia. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 331–344. Wagner, L.E., 2013. A history of wind erosion prediction models in the United States Department of Agriculture: the wind erosion prediction system (WEPS). Aeolian Res. 10, 9–24. Wells, E.C., Mihok, L.D., 2010. Ancient Maya perceptions of soil, land, and Earth. In: Landa, E.R., Feller, C. (Eds.), Soil and Culture. Springer Science + Business Media, Berlin, pp. 311–327. Williams, B.G., Baker, G.C., 1982. An electromagnetic induc- tion technique for reconnaissance surveys of soil salin- ity hazards. Aust. J. Soil Res. 20, 107–118. Williams, B.G., Hoey, D., 1987. The use of electromagnetic induction to detect the spatial variability of the salt and clay contents of soils. Aust. J. Soil Res. 25, 21–27. Worthen, E.L., 1909. Methods of soil surveying. Agron. J. 1 (1), 185–191. Wu, J., Norvell, W.A., Hopkins, D.G., Welch, R.M., 2002. Spatial variability of grain cadmium and soil character- istics in a durum wheat field. Soil Sci. Soc. Am. J. 66, 268–275. Wysocki, D.A., Schoeneberger, P.J., LaGarry, H.E., 2000. Geomorphology of soil landscapes. In: Sumner, M.E. (Ed.), Handbook of Soil Science. CRC Press, Boca Raton, FL, pp. E-5–E-39. Yaalon, D.H., 1975. Conceptual models in pedogenesis: can the soil-forming functions be solved? Geoderma 13, 189–205. Yaalon, D.H., Yaron, B., 1966. Framework for man-made soil changes-an outline of metapedogenesis. Soil Sci. 102 (4), 272–277. Yang, D., Kanae, S., Oki, T., Koike, T., Musiake, K., 2003. Global potential soil erosion with reference to land use and climate changes. Hydrol. Process. 17, 2913–2928. Yassoglou, N., 2005. Soil survey in Greece. In: Jones, R.J.A., Houšková, B., Bullock, P., Montanarella, L. (Eds.), Soil Resources of Europe, second ed. European Soil Bureau, Institute for Environment & Sustainability, JRC Ispra, Italy, pp. 159–168. Zhang, M., Geng, S., Ustin, S.L., Tanji, K.K., 1997. Pesticide occurrence in groundwater in Tulare County. Calif. Environ. Monit. Assess. 45, 101–127. Zitzmann, A., 1994. Geowissenschaftliche Karten in der Bundesrepublik Deutschland. Zeitschrift der Deutschen Geologischen Gesellschaft Band 145, 38–87.
- 38. 29 Soil Mapping and Process Modeling for Sustainable Land Use Management. DOI: © Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/B978-0-12-805200-6.00002-5 2017 Soil Mapping and Processes Modeling for Sustainable Land Management Paulo Pereira1 , Eric C. Brevik2 , Miriam Muñoz-Rojas3,4 , Bradley A. Miller5,6 , Anna Smetanova7,8 , Daniel Depellegrin1 , Ieva Misiune1 , Agata Novara9 and Artemi Cerdà10 1 Mykolas Romeris University, Vilnius, Lithuania 2 Dickinson State University, Dickinson, ND, United States 3 The University of Western Australia, Crawley, WA, Australia 4 Kings Park and Botanic Garden, Perth, WA, Australia 5 Iowa State University, Ames, IA, United States 6 Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany 7 National Institute for Agricultural Research, Paris, France 8 Technical University Berlin, Berlin, Germany 9 University of Palermo, Palermo, Italy 10 University of Valencia, Valencia, Spain C H A P T E R 2 INTRODUCTION Soil is the basis of life and a major supplier of ecosystem services. It is a nonrenewable resource at the human time scale and a medium of interaction among several spheres: the atmosphere, biosphere, hydrosphere, and litho- sphere, and recently with the antroposphere as a consequence of the tremendous impact humans now have on soil properties through agriculture, urbanization, landfills, pollution, and other activities (Yaalon and Yaron, 1966; Richter and Yaalon, 2012; Brevik et al., in press). Soil degradation is a worldwide problem, and it is understood as “a change in the soil health status resulting in a diminished capacity of the ecosystem to provide goods and services for its beneficiaries. Degraded soils have a health status such, that they do not provide the normal goods and services of the particular soil in its ecosystem1 .” Soil degradation is not an exclusive problem of arid and semi- arid environments as a consequence of farming activities. Soil degradation is a consequence of inten- sive land use management, which is assumed to be caused by human impact, poverty, and a response to economic opportunities at the global level (Lambin et al., 2001). There are several examples of human-induced soil 1 http://www.fao.org/soils-portal/soil-degradation- restoration/en/ (consulted on 21.01.16).
- 39. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 30 degradation in arctic (Jefferies and Rockwell, 2002), humid (Graves et al., 2015; Varallya, 1989), tropical (Ali, 2006), and alpine environ- ments (Upadhyay et al., 2005; Wu and Tiessen, 2002) in addition to arid and semi-arid envi- ronments (García-Orenes et al., 2009). Soil deg- radation poses several threats, such as loss of ecosystem services delivery, biodiversity pro- tection, climate change, energy sustainability, food and water security, and productivity stag- nation. All of these aspects are important obsta- cles to sustainability (Bouma and McBratney, 2013). Soil degradation is attributed to erosion, sealing, compaction, nutrient depletion, pol- lution, salinization, and other indirect actions, such as creating unfavorable conditions for soil formation and productivity (Bindraban et al., 2012). In Europe, mean soil losses are estimated to be 2.46tyear−1 and 0.032t ha−1 MJ−1 mm−1 (Panagos et al., 2014b, 2015). Soils are the base of economic activity and the costs of degradation are extremely high (Görlach et al., 2004; Pimentel et al., 1995). Soil degradation has been estimated to cost England and Wales between £0.9 billion and £1.4 billion per year, which are especially attributed to the loss of organic matter, erosion, and compaction (Graves et al., 2015). The economic and envi- ronmental costs of the use of pesticides is esti- mated to be $8 billion per year (Pimentel et al., 1992) and soil erosion $44 billion per year in the United States and $400 billion per year world- wide (Pimentel et al., 1995). Soil cadmium remediation by replacement of contaminated soil is estimated to be United States $3mil- lionha−1 (Chaney et al., 2004). The remediation cost of soil contaminants through stabilization/ stagnation technology in situ varies from US$80 for shallow applications to US$330 for deeper applications per cubic meter (Khan et al., 2004). Looking at the values above, soil degradation and pollution is extremely expensive. In this context, soil degradation is of major importance from an environmental, social, and economic point of view. Maps are widely used to gain a better under- standing of human impacts on the landscape. Degradation processes can be studied and eval- uated using remote sensing techniques (Raina et al., 1993; Vagen et al., 2016), soil erosion mod- els (Prashun et al., 2013), geostatistical mod- els (Diodato and Ceccarelli, 2004), and expert analysis and satellite images (Kheir et al., 2006) in urban and rural environments at diverse scales. The maps produced by these works are important in understanding our impact on the landscape and are an important contribution to develop better territorial planning. Soil maps and soil models are important to plan sustainable use of a given territory and to help identify areas that are vulnerable to human activities, creating a high probability of degradation. Good spatial information and planning can reduce exposure to environmen- tal hazards and risks, the impact of human activities on soil and land degradation, adverse effects on human health, and economic losses and loss of lives (Anaya-Romero et al., 2011). Good planning can contribute to a better envi- ronment (e.g., pollution reduction) and a gen- eral correct use of the land. SOIL AND SUSTAINABLE DEVELOPMENT INTERDEPENDENCE Sustainable development cannot be under- stood without considering soils. Soils are a natural capital and are the source of a num- ber of regulating, provisioning, cultural, waste processing, and supporting ecosystem services (Adhikari and Hartemink, 2016; Calzolari et al., 2016; Robinson et al., 2013) that are indispensa- ble for our existence (Fig. 2.1). These services can be divided into agricultural and nona- gricultural (Fig. 2.2) (Pulleman et al., 2012). According to Powlson et al. (2011), soils pro- vide a wide variety of services to society that are of high environmental significance, such as
- 40. Soil and Sustainable Development Interdependence I. THEORY 31 (1) influence water quality and regulate nutri- ent runoff and percolation, (2) serve as the basis for soil biodiversity, (3) water retention for veg- etation use and transfer to water bodies, (4) influence atmospheric chemistry and act as a sink for greenhouse gases, (5) serve as the base for vegetation development and support for all the living elements of this world, and (6) are the basis for several human and natural activities. The unsustainable use of soil ecosystem services will lead to soil degradation and the emergence of problems with food production and security (Gregory, 2012; Montanarella and Vargas, 2012), one of the most important fac- tors for human social and economic develop- ment. Studies in the Midwestern United States showed that moderate soil erosion led to yield reductions of 16%–23% and severe erosion led to yield reductions of 25%–36% as compared to crops grown in fields with only slight ero- sion (Troeh et al., 2004). The unstainable use of soil services is an issue transversal to the three spheres of sustainable development (Fig. 2.3). The correct or incorrect management of the FIGURE 2.1 Soil ecosystem services. Adapted from Robinson, D.A., Hockley, N., Cooper, D.M., Emmett, B.A., Keith, A.M., Lebron, I., et al., 2013. Natural capital and ecosystem services, developing an appropriate soils framework as a basis for valuation. Soil Boil. Biochem. 57, 1023–1033. http://dx.doi.org/10.1016/j.soilbio.2012.09.008.
- 41. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 32 thin soil layer that covers our planet’s terres- trial areas plays a major role in determining our prosperity or starvation (Robinson et al., 2012). 52% of the areas used for agriculture are mod- erately or severely affected by soil degradation. At the same time, 4–6 million ha of cultivated soils are lost each year as a consequence of human-induced soil degradation and 75 billion tons of soil is lost annually to wind or water erosion (UNCCD, 2009). Human-induced soil degradation and corresponding loss of soil ser- vices is one of the main causes of poverty and starvation as reported by many studies in sev- eral environments (Barbier, 2000; Bindraban et al., 2012; Burras et al., 2013; Ludeke et al., 1999; Scherr, 2000). Soil nutrition status in Africa is statistically significantly correlated with the rate of poverty on the continent; in other words, in countries where soil nutri- ent losses are high the rate of poverty is high as well (ELD Initiative and UNEP, 2015). Food security and production is related to wars and conflicts (Lynch et al., 2013), natural hazards, and climate change related effects that reduce soil quality and productivity, such as extreme droughts and floods (Vermulen et al., 2012; Wheeler and Von Braun, 2013). When food availability is decreased, that tends to have seri- ous impacts on social and economic aspects of households and individuals, problems related to the reduced capacity to work, vulnerability to diseases, and negative impacts on the mental FIGURE 2.2 Relationships between soil organisms, their ecosystem functions and the ecosystem services that they pro- vide to society (Pulleman et al., 2012).
- 42. Soil and Sustainable Development Interdependence I. THEORY 33 and educational development of children (FAO, 2002; Arndt et al., 2012; Wheeler and Von Braun, 2013). In 2015 the world population was 7.3 bil- lion and is estimated to reach approximately 9.5 billion in 2050. From 2005 to 2050, popu- lation growth will increase the demand for agricultural production by approximately 70% (Lal, 2015). In 2013, 38% of the Earth’s soil had been converted into agricultural land, while only 11% of Earth’s soils are considered suita- ble for farming (FAO, 2002; World Bank, 2008).2 This shows that we are greatly exceeding the capacity of our soils due to population growth and demand for food. According to the World Bank, from the 1960s until 2014, there was an increase of more than 100% in crop and food production, livestock production, and cereal yield. A high increase in the use of agricultural machinery and land for agricultural production was identified. On the other hand a decrease of arable hectares per person and in the rural population was observed (Table 2.1). These activities are normally related to an unsustain- able use of soil and land degradation. Feeding a growing population in the future will be a major challenge (Godfray et al., 2010), but the 2 http://wdi.worldbank.org/table/3.2# (consulted on 02.02.16). FIGURE 2.3 Soil degradation causes and drivers (Lal, 2015).
- 43. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 34 challenge is not limited to this. The intensifi- cation of agriculture, overexploitation of soil resources and degradation of soil services are one of the main causes of poverty and is a real threat to food security (Bommarco et al., 2013; Das Gupta, 2016). Agriculture practices also contribute significantly to greenhouse emis- sions. It is estimated that between 2001 and 2011, greenhouse gas emissions increased 14% (EEA, 2015). Intensive agriculture and livestock production is responsible for the emission of great amounts of carbon dioxide (Lal, 2004a) as well as other greenhouse gases such as nitrogen oxide and methane (Linquist et al., 2012). This is mainly attributed to increasing population, consumer demands and changing of food hab- its, which contributed to unsustainable farming practices and soil degradation (De Boer et al., 2013). A shift in human consumption patterns, especially in regards to meat, is a key to reduce agricultural contributions to greenhouse gas emissions (Bouwman et al., 2013). Soils are the largest active reservoir of carbon (±1500 PgC), containing approximately double the carbon present in the atmosphere (Smith, 2012). Soil degradation processes influence the carbon cycle. Soil erosion releases soil organic carbon, and despite the fact that part of this eroded carbon (0.06–0.27PgCyear−1 ) is deposited and stored in landscapes, erosion leads to a net global lateral flux of 0.61PgCyear−1 (Van Oost et al., 2007). Soil–plant systems contribute to car- bon sequestration by removing carbon dioxide from the atmosphere and locking it up in the soil as organic matter, thereby contributing to climate change mitigation. Nevertheless, this capacity to sequester carbon depends on soil texture, struc- ture, rainfall, temperature, farming system, and soil management. No-till management has been widely reported to release less carbon dioxide into the atmosphere compared to intensively tilled systems (Lal, 2004c), although this has been questioned by several researchers (Baker et al., 2007; Blanco-Canqui and Lal, 2008; Christopher et al., 2009; Khan et al., 2007) and carbon seques- tration benefits may be limited to locations with an appropriate climate (Carr et al., 2015; Van den Bygaart et al., 2003). Including cover crops in agricultural management is another technique that holds great promise for sequestration of car- bon in soils (Olson et al., 2014; Poeplau and Don, 2015), and even the effects of management and TABLE 2.1 Percent of Variation of Some Agriculture and Rural Development Variables for the World Acronym Variable % of Variation AMT Agricultural machinery, tractors +60.34 (1962–2001) ALK Agricultural land (km2 ) +21.05 (1962–2014) AGL% Agricultural land (% of land area) +4.48 (1962–2014) ALP Arable land (hectares per person) −88.42 (1962–2014) AL% Arable land (% of land area) +10.67 (1962–2014) LCP Land under cereal production (ha) +27.74 (1962–2014) PC% Permanent cropland (% of land area) +38.31 (1962–2014) AMTSQ Agricultural machinery, tractors per 100km2 of arable land + 50.01 (1962–1999) CPI Crop production index (2004–2006 = 100) +142.43 (1962–2014) FPI Food production index (2004–2006 = 100) +138.85 (1962–2014) LPI Livestock production index (2004–2006 = 100) +129.88 (1962–2014) CY Cereal yield (kgha−1 ) +125.82 (1962–2014) RP Rural population (% of total population) −42.53 (1962–2014) Source: World Bank Database.a a http://data.worldbank.org/topic/agriculture-and-rural- development?display=default (accessed 02.06.16).
- 44. Soil and Sustainable Development Interdependence I. THEORY 35 land use on carbon sequestration in urban soils has been studied and influences found (Bae and Ryu, 2015; Beesley, 2012; Weissert et al., 2016). Thus the way we use any given soil will influ- ence our contribution to or mitigation of global climate change. In the present soil landscape, carbon pools are much reduced as compared to before human intervention. It is estimated that soils have lost between 40 and 90 PgC due to cul- tivation and other disturbances. The correct man- agement of soil, including no-tilling practices, cover crops, and other management techniques that reduce soil degradation, e.g., afforestation, natural rehabilitation, terracing, and organic farming will contribute to a decrease in car- bon dioxide emissions and increase soil carbon sequestration (Lal, 2004b). Managing soil carbon is extremely impor- tant since soil organic matter has an important impact on several soil ecosystem functions. Small changes in soil carbon can have large impacts on soil physical properties (Powlson et al., 2011). In addition, soil carbon sequestration is an extremely valuable regulating ecosystem service and a relatively low-cost option to reduce emis- sions that is very attractive to governments. In this context, for sustainable soil use, it is impor- tant to encourage management practices that pro- mote the preservation and restoration of carbon to soils (Lal, 2004b; Powlson et al., 2011). Several studies have pointed out that carbon farming is one of the most cost-effective alternatives to off- set carbon emissions and to deliver biodiversity benefits via ecosystems restoration and other eco- nomic and social benefits dependent on atmos- pheric carbon reduction (Evans et al., 2015; Funk et al., 2014) that also increase soil carbon (Becker et al., 2013; Cowie et al., 2013). A study carried out in Australia by Evans et al. (2015) observed that assisted natural regeneration sequestered 1.6–2.2 times more carbon than plantations. In addition, the costs for natural regeneration were 60% lower than the plantations. Natural pro- cesses are much less expensive than engineering solutions, such as the transformation of carbon dioxide into carbonates (Lal, 2009). There is much discussion about the eco- nomic value of soil ecosystem services. Although establishing exact financial values for any given service is difficult, the ecosys- tem services provided by soils can have con- siderable value. In New Zealand, Dominati et al. (2014) estimated that the soils they studied provided ecosystem services val- ued at NZ$16,390ha−1 year−1 (approximately US$13,110ha−1 year−1 ). Services included in the Dominati et al. (2014) evaluation were food quantity and quality, support for human infra- structure, support for animals, flood mitiga- tion, filtering of nitrogen, phosphorus, and other contaminants, recycling of wastes, N2O regulation, CH4 oxidation, and regulation of pest and disease populations. Many of the ser- vices provided by soils discussed earlier in this chapter can be seen in the economic eval- uation completed by Dominati et al. (2014). However, demonstrating the difficulty of gen- erating these values and the variability of soils, other researchers have reached very differ- ent values for ecosystem services. In another New Zealand study, Sandhu et al. (2008) esti- mated the value of ecosystem services as being between US$1270 and 19,420ha−1 year−1 , with management making a difference in the value of ecosystem services. Both the Dominati et al. (2014) and Sandhu et al. (2008) studies were done on agricultural soils, which should have a fairly high total ecosystem services value. McBratney et al. (2017) estimated that the eco- system services for all lands globally, including nonagricultural lands, deserts, etc., were valued at about US$867ha−1 year−1 , considerably less than the values typically calculated for agricul- tural lands. In all of these studies the use the land was put to, the ecosystem services con- sidered (or left out), and the values assigned to each ecosystem service made a major difference in the final results.
- 45. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 36 SUSTAINABLE LAND MANAGEMENT AND SOIL MAPS Definition and Principles Sustainable land management aims to inte- grate water, biodiversity, land and environ- mental management aspects to meet increasing food, feed, fiber, and bioenergy demands while maintaining the sustainability of ecosystem services and livelihoods. Achieving this is a fundamental need, especially since intensive exploitation of soil and ecosystems can lead to land degradation and the loss of ecosystem services capacity, and undermines ecosystems’ resilience and adaptability (Schwilch et al., 2010; World Bank, 2008). The Earth Summit (1992) defined sustainable land management as “the use of land resources, including soils, water, animals, and plants, for the production of goods to meet changing human needs, while simultaneously ensuring the long-term productive potential of these resources and the maintenance of their environ- mental functions.” According to the World Bank (2008) the goals of sustainable land manage- ment are 1. “Preserving and enhancing the productive capabilities of cropland, forestland, and grazing land (such as upland areas, down-slope areas, flatlands, and bottomlands)” 2. “Sustaining productive forest areas and potentially commercial and non-commercial forest reserves” 3. “Maintaining the integrity of watersheds for water supply and hydropower generation needs and water conservation zones” 4. “Maintaining the ability of aquifers to serve the needs of farm and other productive activities” Management should be focused on reduced land degradation, increased productivity, and sustainable use of the soil resource. There should be a participative approach, involving all interested stakeholders in land use planning to arrive at the use of acceptable techniques and methods to avoid overexploitation of natu- ral resources and inappropriate management. These goals should be achieved by empowering local communities and land managers, use of local resources in sustainable land management implementation, sharing information and expe- riences, and raising the importance of water- shed management at the government level (UNDP, 2014). Sustainable land management is divided into six components, (1) understanding the ecol- ogy of land use management, (2) maintaining or enhancing productivity, (3) maintenance of soil quality, (4) increasing diversity for high sta- bility and resilience, (5) provision of economic and ecosystem service benefits for communi- ties, and (6) social acceptability (Montavalli et al., 2013). According to FAO (1993), sustain- able land management should meet four dif- ferent criteria, (1) production levels should be maintained, (2) risk of production should not increase, (3) soil and water quality should be preserved, and (4) systems should be accepted by the society where they are being imple- mented and economically feasible. Finally, for TerraAfrica3 sustainable land management principles are based on (1) increased land productivity, (2) improved livelihoods, and (3) improved ecosystems. Sustainable land management has a strong ecological, social, and economic component, dependent upon effec- tively combatting land degradation to ensure the sustainability of livelihoods and food secu- rity and ability to pay back the investments taken out by land user communities or govern- ments (Liniger et al., 2011) (Fig. 2.4). 3 http://www.terrafrica.org/sustainable-land- management-platform/what-does-slm-achieve (consulted on 02.02.16).
- 46. Sustainable Land Management and Soil Maps I. THEORY 37 Sustainable Land Management Need: The Water Question Sustainable land management is fundamen- tal for future generations. Human activities are indeed responsible for the transformation of Earth’s surface and soil degradation, with humans now representing the single most defin- ing geomorphic force of our time (Steffen et al., 2015; Zalasiewicz et al., 2015) and functioning as a soil forming factor (Yaalon and Yaron, 1966; Richter and Yaalon, 2012). According to a WWF (2014) report, we need 1.5 planets to meet our present demands on nature. We are consuming resources from the planet faster than they can be regenerated. Agriculture is having a huge impact on water consumption. Our unsustain- able water demands and the increasing scar- city imposed by pollution and climate change are creating critical levels in water availability (Kresic, 2009; WWF, 2014). Globally, the inten- sive application of fertilizers and irrigation water to arable land is way too high (Aguilera et al., 2013), which can produce long-term loss of natural capital, including soil productiv- ity and increased soil pollution with potential impacts on human health, especially if waste- water is used as a soil amendment (Khan et al., 2008; OECD, 2012; Wang et al., 2012). Irrigated systems are not well adapted to today’s agri- culture and the level of productivity is much reduced, representing a loss of resources, effi- ciency, and economic values. From 1961 to 2009 the irrigated cultivation area increased 117% and is expected to increase by 127%–129% by 2050 in relation to 1961 (FAO, 2011). This unsustainable growth leads to extremely high consumption of water resources. 10%–25% of rainfall is lost to runoff and evaporation, and as a consequence of these losses, only between FIGURE 2.4 Principles for the best sustainable land management (Liniger et al., 2011).
- 47. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 38 15% and 30% of rain is typically used for plant development (FAO, 2011). Husbandry practices, intensive farming, and development of irriga- tion technologies are responsible for the increas- ing unstainable use of water resources (FAO, 2011; Liniger et al., 2011; World Bank, 2008). For these reasons, sustainable land management, which includes sustainable use of our water resources in the production of food, feed, fiber, and fuel, is extremely important to ensure sus- tainability for future generations. Sustainable Land Management Practices and Indicators Sustainable land management practices are fundamental for the preservation and quality of the soil. They are a key aspect of the delivery of regulating, supporting, providing and cultural ecosystem services, and are connected to our well-being as mentioned earlier in this chapter (Fig. 2.5). Several practices have been devel- oped to ensure soil productivity. However, the FIGURE 2.5 Interdependence between human well-being choices, ecosystems services, land use management, and the human–environment system (based on Buenemann et al., 2011).
- 48. Sustainable Land Management and Soil Maps I. THEORY 39 application of these measures is often difficult to implement and adopt due to different inter- ests of the stakeholders involved in land use management (World Bank, 2008). Sustainable land management is divided into cultivated and noncultivated techniques as shown in Fig. 2.6. Several methodologies have been developed to monitor and assess sustainable land man- agement at local levels by applying the World Overview of Conservation Approaches and Technologies (WOCAT) guidelines, which have been used lately in the assessment of land deg- radation by the Land Degradation Assessment in Drylands (LADA) and EU-Desire projects. The main objective of monitoring and assess- ment procedures is to analyze and create solid information for decision and policy-makers at several levels (Schwilch et al., 2010). Multiple attempts have been made to define the best indicators for assessing and monitor- ing sustainable land management. According to Cornforth (1999) the indicators should (1) be selected from the outputs of production, (2) influence the product value, and (3) have impacts on the production at local and other levels. The selected environmental indicators must also be (1) sensitive and responsive to changes in land management, (2) important in the assessed area, (3) related to ecosystem process, (4) scientifically valid, (5) use exist- ing data, (6) easy and cheap to measure, (7) not complex, (8) accessible to land users, man- agers, scientists, and policy-makers, (9) inter- nationally recognized, and (10) strong enough to support political decisions (Cornforth, 1999). Soil quality indicators, which are fun- damental to assess sustainable land manage- ment are divided into three categories. These are (1) develop in the near term, (2) require longer term research, and (3) developed by other networks. Sustainable land manage- ment indicators, on the other hand, are based FIGURE 2.6 Sustainable land management practices in cultivated and noncultivated environments. Adapted from UNDP, 2014. Sustainable Land Management Toolkit. Available from: http://www.ls.undp.org/content/lesotho/en/home/library/environment_ energy/SLM-Toolkit.html (consulted on 15.03.16).
- 49. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 40 on their productivity, security, protection, vari- ability, and acceptability (Table 2.2) (Dumanski et al., 1998). More recently the KM: Land pro- ject developed five global indicators, measur- able at the project level, in order to assess the complexities of land degradation processes and sustainable land management, which depend upon biophysical, social, political, eco- nomic, and cultural factors (UNU-INWEH, 2011). These indicators consider land use/cover aspects, productivity in different land use types and systems, water resources, and human well- being (Fig. 2.7). Despite the existence of these common and global indicators, it is important to develop indicators adapted to the local real- ity of the studied area. Several studies have pointed out the importance of integrating local with scientific knowledge in the development of effective sustainable land management plans and reducing land degradation on several con- tinents, such as Africa (Reed et al., 2007), Asia and Oceania (Lefroy et al., 2000), and South and Central America (Barrera-Bassols and Toledo, 2005). In many cases, local knowledge is consid- ered to be the core of the programs developed. Sustainable Land Management Monitoring and Assessment Monitoring and assessment studies have tra- ditionally been more focused on land degrada- tion rather than on the sustainable management of land. Studies focused on the social, eco- nomic, and environmental costs and benefits of sustainable land management are largely lack- ing. The available works show that sustainable land management is positively associated with land tenure security in middle and advanced economies. In countries with lower incomes, this association was not observed since secure land tenure is not related to unsustainable farming practices (Nkonya et al., 2008). Diao and Sarpong (2011) estimated that sustainable land management practices applied in Ghana between 2006 and 2015 increased total benefits by $6.4 billion, reducing poverty. If farmers perceive economic advantages from the adop- tion of sustainable land use practices, it will facilitate the implementation of these meas- ures. Kassie et al. (2010) found that farmers TABLE 2.2 Common Indicators for Land Use Quality and Sustainable Land Management (Dumanski et al., 1998) Land quality Developed in the near term Nutrient balance Yield gap Land use intensity Requiring longer term research Soil quality Land degradation Agrobiodiversity Developed by other networks Water quality Forest land quality Rangeland quality Soil pollution Sustainable land management Productivity Crop yield Security Soil cover Yield Variability Climate Protection Soil and water quality/ quantity Biological diversity Viability Net farm profitability Input use efficiency Pesticides, fertilizers, nutrients Off-farm income Return to labor Acceptability Use of conservation practices Farm decision-making criteria
- 50. Sustainable Land Management and Soil Maps I. THEORY 41 who used minimum tillage in areas with low agricultural potential had higher productivity compared to farmers who used commercial fertilizers. This facilitated the adoption of mini- mum tillage in the studied areas. Observed in a survey carried out in several parts of the world that the great majority of the farmers interviewed (97%) acknowledged the long- term benefits of the implementation of sus- tainable land use practices and technologies. Nevertheless, there are cases where such prac- tices are not implemented because of lack of knowledge about these practices due the lack of communication between scientists and land managers and guidance on environmental questions. There are also cases where sustain- able practices are not adapted for cultural rea- sons (Burras et al., 2013; Sandor et al., 2006). Therefore it is important to invest in commu- nication of scientific results to land owners and managers to demonstrate the advantages of using sustainable land use practices, and it is also important to work with local com- munities to identify practices that are cultur- ally acceptable. According to Mirzabaev et al. (2015), there are three reasons to promote more investments in sustainable land management (1) the social costs of land degradation are very high in the global community compared to private interests, (2) the private costs of land degradation in some cases are much higher than the costs of inaction; this may also partly be a consequence of lack of knowledge about sustainable management practices or barri- ers imposed by policy makers, and (3) despite the fact that land owners understand the direct costs imposed by land degradation, they are still resistant to invest in sustainable land man- agement measures. The challenge is to show the advantage of long-term benefits to heads of households and decision makers that normally are not part of political agendas and to supply them with fiscal security during the transition period to new management practices. From the economic point of view, soil and land degrada- tion do not need any intervention. This only happens when the market fails and the con- sequent results impact on the social sphere. At this level the costs of soil rehabilitation are very likely higher than the costs of sustainable land management practices (Mirzabaev et al., 2015; Shiferaw and Holden, 2000). In Africa it is esti- mated that the costs of inaction against land degradation are seven times higher than the FIGURE 2.7 Global sustainable land management impacts and measurable indicators at a project level (UNU-INWEH, 2011).
- 51. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 42 costs of implementing sustainable land manage- ment practices (ELD Initiative and UNEP, 2015). It has been estimated that the global cost of soil erosion is about five times higher than the cost of prevention would be (Pimentel et al., 1995). Thus it is of major importance to continue to implement sustainable land management prac- tices adapted to the different realities and get evidence that these practices are effective at decreasing soil and land degradation and that they improve soil productivity and the social and economic conditions of households that implement them. Soil Spatial Analysis, Mapping, and Sustainable Land Management Sustainable land management planning requires geospatial analyses and mapping that are integrative. Such planning needs to have the capacity to link quantitative and qualitative data that characterizes the natural and human environments. Spatial analysis enhances under- standing of interactions occurring on the land- scape and exactly where those interactions are likely to lead to soil degradation. Developing our abilities in these areas will contribute strongly to understanding the degree of the impacts of land use (Buenemann et al., 2011). A correct, effective, and integrative geospatial approach to monitoring and assessing sustain- able land management needs to (1) provide spatial information about risks and vulnerabili- ties, (2) identify interrelations between human and environmental dimensions at micro, local, regional, and macroscales, (3) provide sugges- tions for alternative land management, (4) con- sider accuracy and uncertainty analysis, and (5) recognize the unique characteristics of local environments (Buenemann et al., 2011). Sustainable land management needs to be done at a wide range of spatial scales. A large effort has been made to map land degrada- tion using expert analysis within the frame- work of WOCAT, LADA, and DESIRE at the international scale (Bouma, 2002; Reed et al., 2011). The WOCAT–LADA–DESIRE mapping was based on land use systems at the national level, similar to CORINE land cover classification for the European Union. CORINE is the Coordination of Information on the Environment program promoted by the European Commission in 1985 for the assess- ment of environmental quality in Europe. The CORINE Land Cover project provides consist- ent information on land cover and land cover changes across Europe (Neumann et al., 2007). According to the different land uses, experts assessed the actual land degradation and the practices carried out for sustainable land use. The information obtained from the survey was georeferenced using geographic information systems (GIS) techniques, producing a map with the level of conservation practices and land degradation of the assessed area (LADA, 2013). Nowadays the use of land use classifica- tion is extensively used for expert evaluation of ecosystem services at national (Egoh et al., 2008), regional (Burkhard et al., 2009; Palomo et al., 2013), and catchment levels (Vrebos et al., 2015). Despite the importance of the expert infor- mation, more reliable data are necessary to have a good assessment of land degradation and sustainable land management. One example of this is soil data. Soil maps are an extremely important source of information to assess these parameters at any scale. Soils are the basis for sustainable land management and in the iden- tification of the first indicators of land degra- dation. In this context, it is of major relevance to have a high quality, quantitative soil data- base. Land use maps connected with soil, topo- graphical, and climate maps allow us to create a spatial and temporal view of the areas that are most vulnerable to land degradation and that may need urgent implementation of sus- tainable land management practices. Several projects at the international level, such as the Global Assessment of Land Degradation and
- 52. Sustainable Land Management and Soil Maps I. THEORY 43 Improvement (GLASOD), that aimed to map land degradation did not use real soil data but developed indices based on remote sensing techniques to estimate land degradation instead (GLASOD),4 this is done when adequate soil information is not available. In the case of the GLASOD, net primary productivity was used as an indirect estimation of soil erosion, salinity, and nutrient depletion (Bai et al., 2010). Despite the large extent and the coarse resolution (8km) used in this work, soil data would have been useful to validate the estimations made using net primary production, because expert evalu- ations in GLASOD were not very accurate nor reliable (Sonneveld and Dent, 2009). As in other cases such as the EU-project Pan-European Soil Erosion Risk Assessment (PESERA) (Kirby et al., 2004), the results produced have been criticized because of the lack of calibration and validation (Reed et al., 2011). At the European level, in the last few years there has been a big effort to cre- ate a better soil database in digital format and made freely available for public use5 (Fig. 2.8), including the production of maps of different soil properties for policy making and public use (Panagos et al., 2012). The availability of this information is very important for scientists, but for land managers the use is quite limited because the resolution (1km2 ) is too coarse for land managers to utilize in a meaningful way. Digital information at finer resolutions is needed to make the soil information useful for managers. This problem is also currently observed in other sources of information such as the Global Facility Soil Information6 where the soil grid’s information is at a resolution of 1km2 . Despite the evident value of this data- base, several concerns arise regarding their use as the accuracy of the predictions of soil prop- erties and class values only exceeded 50% in a few cases. That modeling effort was not able to detect much of the spatial variability, and it is biased by an unequal distribution of the soil profiles used to create it. Areas of Canada, North Africa, Russia, and Central Asia are very poorly covered with quality soil data (Hengl et al., 2014). This creates problems regarding the valid- ity of predictions made using these databases. In addition, many of the areas that are poorly represented are arid and semi-arid environ- ments, among the most vulnerable areas to land degradation or sustainable land management issues. To tackle these questions a better spatial distribution of the soil information collected is needed. Efforts to address that issue compliment and support the need to use more robust statis- tical methods to improve the accuracy of soil property predictions (Brevik et al., 2016). Recent work by Hengl et al. (2015) tried to tackle these problems by downscaling a 1km2 resolution (global coverage) soil map (Hengl et al., 2014) to a 250m2 resolution using the same database, but only applied to Africa. The result- ing map had a finer resolution and predictions carried out at a 250m resolution were better than the ones observed at 1km2 . The use of the random forests statistical techniques helped improve the accuracy of the spatial predictions from the 1km2 resolution to the 250m resolu- tion applied to Africa. Soil data availability was extremely relevant for increasing the accuracy of the predictions (Hengl et al., 2015). The find- ings of this work are highly relevant to the ques- tion of land degradation assessment and the implementation of sustainable development practices in Africa, which is recognized as the continent with the most serious problems related to land degradation and most in need of sustain- able land use practices. Each year, Africa loses approximately 280 million tons of cereal from 105 million hectares of croplands where soil erosion could be managed (ELD Initiative and UNEP, 2015). 6 http://www.isric.org/projects/ global-soil-information-facilities-gsif. 4 http://www.fao.org/nr/lada/gladis/gladis_db/. 5 http://esdac.jrc.ec.europa.eu/resource-type/ soil-data-maps.
- 53. Chapter 2. Soil Mapping and Processes Modeling for Sustainable Land Management I. THEORY 44 Downscaling methods using remote sensing for mapping have been extensively applied to estimate soil hydraulic properties, especially water content (Crow et al., 2000; Djamai et al., 2015; Kim and Barros, 2002; Ray et al., 2010). Recently, several remote sensing methods have been applied to estimate and map other soil properties. A review of these methods can be FIGURE 2.8 Topsoil carbon distribution in European Union countries. Source: http://esdac.jrc.ec.europa.eu/public_path/ OCTOP.png.
- 54. Sustainable Land Management and Soil Maps I. THEORY 45 found in Mulder et al. (2011) and Brevik et al. (2016). On the other side, upscaling soil prop- erties has been frequently used for mapping soil properties at plot (Sundqvist et al., 2015), catchment (Crow et al., 2012; Taylor et al., 2013), regional (Horta et al., 2014; Xu et al., 2013), and country (Constantini and L’Abate, 2016) levels. Both upscaling and downscaling will continue to be relevant to soil mapping, particularly where high-resolution soil surveys are not a reality (Malone et al., 2013). More investments are needed to provide better spatial coverage of soil data. Soil Models Contribution to Sustainable Land Management Out of necessity, models simplify reality and are used to understand the complexity of envi- ronmental systems. There are three basic types of models used in environmental studies, pro- cess-based models, empirical models, and con- ceptual models. Empirical models are the most simple of the models, while conceptual models are considered to have a degree of complexity between empirical and process-based models (Letcher and Jakeman, 2010). Process-based or mechanistic models are used to simulate past, present, and future changes, based on the representation of the components and their interactions in a deter- mined environmental system. These models give a numerical solution over a determined time and space. In other words, they assume changes in the quantities of the studied vari- ables (state variables). These variables are expressed by differential equations and driven by fluxes formulated as rates of processes, known as rate variables. Process-based models require large computing costs and are based on the existence of a large number of parameters distributed within the investigated space that can be, in theory, measured within the system analyzed; this is one of the limitations of their applicability. However, when a large number of parameters are involved and due to our inability to correctly measure the heterogene- ity of the parameters involved, the errors of measurement can be important, increasing the uncertainty of the models. In practice, process- based models may include some empirical data and the correlation existents in empirical mod- els can be useful to assume a link to a process. Process-based models are mainly applied in ocean and atmosphere models, climate mod- eling, and subsurface hydrological modeling (Adams et al., 2013; Letcher and Jakeman, 2010; Wali et al., 2010). Empirical models (correlative or statistical models) are focused on the statistical correla- tion among the variables involved, but without describing the system behavior, rules, interac- tions, and structure in detail. Empirical mod- eling is divided into three stages, (1) selection of the predictor variables, (2) model calibration, and (3) validation. They are mainly designed to predict and depend on data to quantify the response of a determined system as a function of a small number causal variables. Several empirical models are based on data analysis using a stochastic approach, which is ideal to explore data patterns and identify hidden rela- tions between the variables. These models do not require explanation of the processes or structures occurring in the studied system. In this type of model the uncertainty is reduced, however, some bias can be observed as a conse- quence of the exclusion of important variables or processes in the system. Empirical models are commonly applied in agricultural, ecologi- cal, and ecotoxicological studies (Adams et al., 2013; Bradford and Fierer, 2012; Koltermann and Gorelick, 1996; Wali et al., 2010). Some mod- els use a hybrid approach and combine process- based methods and empirical representation of relationships (Adams et al., 2013; Korzukhin et al., 1996; Letcher and Jakeman, 2010; Makela et al., 2000; Perez-Cruzado et al., 2011). Conceptual or mental models are based on simple representations of the system,
- 55. Exploring the Variety of Random Documents with Different Content
- 56. “He knows now,” answered Barrington. “That’s enough. They don’t allow servants here: I must have a fag in place of one.” In turning his fascinated eyes from Barrington, Hearn saw Blair standing by, our mathematical master—of whom you will hear more later. Blair must have caught what passed: and little Hearn appealed to him. “Am I obliged to be his fag, sir?” Mr. Blair put us leisurely aside with his hands, and confronted the new fellow. “Your name is Barrington, I think,” he said. “Yes, it is,” said Barrington, staring at him defiantly. “Allow me to tell you that ‘fags’ are not permitted here. The system would not be tolerated by Dr. Frost for a moment. Each boy must wait on himself, and be responsible for himself: seniors and juniors alike. You are not at a public-school now, Barrington. In a day or two, when you shall have learnt the customs and rules here, I dare say you will find yourself quite sufficiently comfortable, and see that a fag would be an unnecessary appendage.” “Who is that man?” cried Barrington, as Blair turned away. “Mathematical master. Sees to us out of hours,” answered Bill Whitney. “And what the devil did you mean by making a sneaking appeal to him?” continued Barrington, seizing Hearn roughly. “I did not mean it for sneaking; but I could not do what you wanted,” said Hearn. “He had been listening to us.” “I wish to goodness that confounded fool, Taptal, had been sunk in his horse-pond before he put me to such a place as this,” cried Barrington, passionately. “As to you, you sneaking little devil, it seems I can’t make you do what I wanted, fags being forbidden fruit here, but it shan’t serve you much. There’s to begin with.”
- 57. Hearn got a shake and a kick that sent him flying. Blair was back on the instant. “Are you a coward, Mr. Barrington?” “A coward!” retorted Barrington, his eyes flashing. “You had better try whether I am or not.” “It seems to me that you act like one, in attacking a lad so much younger and weaker than yourself. Don’t let me have to report you to Dr. Frost the first day of your arrival. Another thing—I must request you to be a little more careful in your language. You have come amidst gentlemen here, not blackguards.” The matter ended here; but Barrington looked in a frightful rage. It was unfortunate that it should have occurred the day he entered; but it did so, word for word, as I have written it. It set some of us rather against Barrington, and it set him against Hearn. He didn’t “lick him into next week,” but he gave him many a blow that the boy did nothing to deserve. Barrington won his way, though, as the time went on. He had a liberal supply of money, and was open-handed with it; and he would often do a generous turn for one and another. The worst of him was his roughness. At play he was always rough; and, when put out, savage as well. His strength and activity were something remarkable; he would not have minded hard blows himself, and he showered them out on others with no more care than if we had been made of pumice-stone. It was Barrington who introduced the new system at football. We had played it before in a rather mild way, speaking comparatively, but he soon changed that. Dr. Frost got to know of it in time, and he appeared amongst us one day when we were in the thick of it, and stopped the game with a sweep of his hand. They play it at Rugby now very much as Barrington made us play it then. The Doctor— standing with his face unusually red, and his shirt and necktie unusually white, and his knee-buckles gleaming—asked whether we
- 58. were a pack of cannibals, that we should kick at one another in that dangerous manner. If we ever attempted it again, he said, football should be stopped. So we went back to the old way. But we had tried the new, you see: and the consequence was that a great deal of rough play would creep into it now and again. Barrington led it on. No cannibal (as old Frost put it) could have been more carelessly furious at it than he. To see him with his sallow face in a heat, his keen black eyes flashing, his hat off, and his straight hair flung back, was not the pleasantest sight to my mind. Snepp said one day that he looked just like the devil at these times. Wolfe Barrington overheard him, and kicked him right over the hillock. I don’t think he was ill- intentioned; but his strong frame had been untamed; it required a vent for its superfluous strength: his animal spirits led him away, and he had never been taught to put a curb on himself or his inclinations. One thing was certain—that the name, Wolfe, for such a nature as his, was singularly appropriate. Some of us told him so. He laughed in answer; never saying that it was only shortened from Wolfrey, his real name, as we learnt later. He could be as good a fellow and comrade as any of them when he chose, and on the whole we liked him a great deal better than we had thought we should at first. As to his animosity against little Hearn, it was wearing off. The lad was too young to retaliate, and Barrington grew tired of knocking him about: perhaps a little ashamed of it when there was no return. In a twelvemonth’s time it had quite subsided, and, to the surprise of many of us, Barrington, coming back from a visit to old Taptal, his guardian, brought Hearn a handsome knife with three blades as a present. And so it would have gone on but for an unfortunate occurrence. I shall always say and think so. But for that, it might have been peace between them to the end. Barrington, who was defiantly independent, had betaken himself to Evesham, one half-holiday, without leave. He walked straight into some mischief there, and
- 59. broke a street boy’s head. Dr. Frost was appealed to by the boy’s father, and of course there was a row. The Doctor forbade Barrington ever to stir beyond bounds again without first obtaining permission; and Blair had orders that for a fortnight to come Barrington was to be confined to the playground in after-hours. Very good. A day or two after that—on the next Saturday afternoon —the school went to a cricket-match; Doctor, masters, boys, and all; Barrington only being left behind. Was he one to stand this? No. He coolly walked away to the high- road, saw a public conveyance passing, hailed it, mounted it, and was carried to Evesham. There he disported himself for an hour or so, visited the chief fruit and tart shops; and then chartered a gig to bring him back to within half-a-mile of the school. The cricket-match was not over when he got in, for it lasted up to the twilight of the summer evening, and no one would have known of the escapade but for one miserable misfortune—Archie Hearn happened to have gone that afternoon to Evesham with his mother. They were passing along the street, and he saw Barrington amidst the sweets. “There’s Wolfe Barrington!” said Archie, in the surprise of the moment, and would have halted at the tart-shop; but Mrs. Hearn, who was in a hurry, did not stop. On the Monday, she brought Archie back to school: he had been at home, sick, for more than a week, and knew nothing of Barrington’s punishment. Archie came amongst us at once, but Mrs. Hearn stayed to take tea with her sister and Dr. Frost. Without the slightest intention of making mischief, quite unaware that she was doing so, Mrs. Hearn mentioned incidentally that they had seen one of the boys—Barrington—at Evesham on the Saturday. Dr. Frost pricked up his ears at the news; not believing it, however: but Mrs. Hearn said yes, for Archie had seen him eating tarts at the confectioner’s. The Doctor finished his tea, went to his study, and sent for Barrington. Barrington denied it. He was not in the habit of telling lies, was too fearless of consequences to do
- 60. anything of the sort; but he denied it now to the Doctor’s face; perhaps he began to think he might have gone a little too far. Dr. Frost rang the bell and ordered Archie Hearn in. “Which shop was Barrington in when you saw him on Saturday?” questioned the Doctor. “The pastrycook’s,” said Archie, innocently. “What was he doing?” blandly went on the Doctor. “Oh! no harm, sir; only eating tarts,” Archie hastened to say. Well—it all came out then, and though Archie was quite innocent of wilfully telling tales; would have cut out his tongue rather than have said a word to injure Barrington, he received the credit of it now. Barrington took his punishment without a word; the hardest caning old Frost had given for many a long day, and heaps of work besides, and a promise of certain expulsion if he ever again went off surreptitiously in coaches and gigs. But Barrington thrashed Hearn worse when it was over, and branded him with the name of Sneak. “He will never believe otherwise,” said Archie, the tears of pain and mortification running down his cheeks, fresh and delicate as a girl’s. “But I’d give the world not to have gone that afternoon to Evesham.” A week or two later we went in for a turn at “Hare and Hounds.” Barrington’s term of punishment was over then. Snepp was the hare; a fleet, wiry fellow who could outrun most of us. But the hare this time came to grief. After doubling and turning, as Snepp used to like to do, thinking to throw us off the scent, he sprained his foot, trying to leap a hedge and dry ditch beyond it. We were on his trail, whooping and halloaing like mad; he kept quiet, and we passed on and never saw him. But there was no more scent to be seen, and we found we had lost it, and went back. Snepp showed up then, and the sport was over for the day. Some went home one way, and some another; all of us were as hot as fire, and thirsting for water.
- 61. “If you’ll turn down here by the great oak-tree, we shall come to my mother’s house, and you can have as much water as you like,” said little Hearn, in his good-nature. So we turned down. There were only six or seven of us, for Snepp and his damaged foot made one, and most of them had gone on at a quicker pace. Tod helped Snepp on one side, Barrington on the other, and he limped along between them. It was a narrow red-brick house, a parlour window on each side the door, and three windows above; small altogether, but very pretty, with jessamine and clematis climbing up the walls. Archie Hearn opened the door, and we trooped in, without regard to ceremony. Mrs. Hearn—she had the same delicate face as Archie, the same pink colour and bright brown eyes—came out of the kitchen to stare at us. As well she might. Her cotton sleeves were turned up to the elbows, her fingers were stained red, and she had a coarse kitchen cloth pinned round her. She was pressing black currants for jelly. We had plenty of water, and Mrs. Hearn made Snepp sit down, and looked at his foot, and put a wet bandage round it, kneeling before him to do it. I thought I had never seen so nice a face as hers; very placid, with a sort of sad look in it. Old Betty, that Hearn used to talk about, appeared in a short blue petticoat and a kind of brown print jacket. I have seen the homely servants in France, since, dressed very similarly. Snepp thanked Mrs. Hearn for giving his foot relief, and we took off our hats to her as we went away. The same night, before Blair called us in for prayers, Archie Hearn heard Barrington giving a sneering account of the visit to some of the fellows in the playground. “Just like a cook, you know. Might be taken for one. Some coarse bunting tied round her waist, and hands steeped in red kitchen stuff.” “My mother could never be taken for anything but a lady,” spoke up Archie bravely. “A lady may make jelly. A great many ladies prefer to
- 62. do it themselves.” “Now you be off,” cried Barrington, turning sharply on him. “Keep at a distance from your betters.” “There’s nobody in the world better than my mother,” returned the boy, standing his ground, and flushing painfully: for, in truth, the small way they were obliged to live in, through Chancery retaining the property, made a sore place in a corner of Archie’s heart. “Ask Joseph Todhetley what he thinks of her. Ask John Whitney. They recognize her for a lady.” “But then they are gentlemen themselves.” It was I who put that in. I couldn’t help having a fling at Barrington. A bit of applause followed, and stung him. “If you shove in your oar, Johnny Ludlow, or presume to interfere with me, I’ll pummel you to powder. There.” Barrington kicked out on all sides, sending us backward. The bell rang for prayers then, and we had to go in. The game the next evening was football. We went out to it as soon as tea was over, to the field by the river towards Vale Farm. I can’t tell much about its progress, except that the play seemed rougher and louder than usual. Once there was a regular skirmish: scores of feet kicking out at once; great struggling, pushing and shouting: and when the ball got off, and the tail after it in full hue and cry, one was left behind lying on the ground. I don’t know why I turned my head back; it was the merest chance that I did so: and I saw Tod kneeling on the grass, raising the boy’s head. “Holloa!” said I, running back. “Anything wrong? Who is it?” It was little Hearn. He had his eyes shut. Tod did not speak. “What’s the matter, Tod? Is he hurt?”
- 63. “Well, I think he’s hurt a little,” was Tod’s answer. “He has had a kick here.” Tod touched the left temple with his finger, drawing it down as far as the back of the ear. It must have been a good wide kick, I thought. “It has stunned him, poor little fellow. Can you get some water from the river, Johnny?” “I could if I had anything to bring it in. It would leak out of my straw hat long before I got here.” But little Hearn made a move then, and opened his eyes. Presently he sat up, putting his hands to his head. Tod was as tender with him as a mother. “How do you feel, Archie?” “Oh, I’m all right, I think. A bit giddy.” Getting on to his feet, he looked from me to Tod in a bewildered manner. I thought it odd. He said he wouldn’t join the game again, but go in and rest. Tod went with him, ordering me to keep with the players. Hearn walked all right, and did not seem to be much the worse for it. “What’s the matter now?” asked Mrs. Hall, in her cranky way; for she happened to be in the yard when they entered, Tod marshalling little Hearn by the arm. “He has had a blow at football,” answered Tod. “Here”—indicating the place he had shown me. “A kick, I suppose you mean,” said Mother Hall. “Yes, if you like to call it so. It was a blow with a foot.” “Did you do it, Master Todhetley?” “No, I did not,” retorted Tod.
- 64. “I wonder the Doctor allows that football to be played!” she went on, grumbling. “I wouldn’t, if I kept a school; I know that. It is a barbarous game, only fit for bears.” “I am all right,” put in Hearn. “I needn’t have come in, but for feeling giddy.” But he was not quite right yet. For without the slightest warning, before he had time to stir from where he stood, he became frightfully sick. Hall ran for a basin and some warm water. Tod held his head. “This is through having gobbled down your tea in such a mortal hurry, to be off to that precious football,” decided Hall, resentfully. “The wonder is, that the whole crew of you are not sick, swallowing your food at the rate you do.” “I think I’ll lie on the bed for a bit,” said Archie, when the sickness had passed. “I shall be up again by supper-time.” They went with him to his room. Neither of them had the slightest notion that he was seriously hurt, or that there could be any danger. Archie took off his jacket, and lay down in his clothes. Mrs. Hall offered to bring him up a cup of tea; but he said it might make him sick again, and he’d rather be quiet. She went down, and Tod sat on the edge of the bed. Archie shut his eyes, and kept still. Tod thought he was dropping off to sleep, and began to creep out of the room. The eyes opened then, and Archie called to him. “Todhetley?” “I am here, old fellow. What is it?” “You’ll tell him I forgive him,” said Archie, speaking in an earnest whisper. “Tell him I know he didn’t think to hurt me.” “Oh, I’ll tell him,” answered Tod, lightly. “And be sure give my dear love to mamma.”
- 65. “So I will.” “And now I’ll go to sleep, or I shan’t be down to supper. You will come and call me if I am not, won’t you?” “All right,” said Tod, tucking the counterpane about him. “Are you comfortable, Archie?” “Quite. Thank you.” Tod came on to the field again, and joined the game. It was a little less rough, and there were no more mishaps. We got home later than usual, and supper stood on the table. The suppers at Worcester House were always the same—bread and cheese. And not too much of it. Half a round off the loaf, with a piece of cheese, for each fellow; and a drop of beer or water. Our other meals were good and abundant; but the Doctor waged war with heavy suppers. If old Hall had had her way, we should have had none at all. Little Hearn did not appear; and Tod went up to look after him. I followed. Opening the door without noise, we stood listening and looking. Not that there was much good in looking, for the room was in darkness. “Archie,” whispered Tod. No answer. No sound. “Are you asleep, old fellow?” Not a word still. The dead might be there; for all the sound there was. “He’s asleep, for certain,” said Tod, groping his way towards the bed. “So much the better, poor little chap. I won’t wake him.” It was a small room, two beds in it; Archie’s was the one at the end by the wall. Tod groped his way to it: and, in thinking of it afterwards, I wondered that Tod did go up to him. The most natural
- 66. thing would have been to come away, and shut the door. Instinct must have guided him—as it guides us all. Tod bent over him, touching his face, I think. I stood close behind. Now that our eyes were accustomed to the darkness, it seemed a bit lighter. Something like a cry from Tod made me start. In the dark, and holding the breath, one is easily startled. “Get a light, Johnny. A light!-quick! for the love of Heaven.” I believe I leaped the stairs at a bound. I believe I knocked over Mother Hall at the foot. I know I snatched the candle that was in her hand, and she screamed after me as if I had murdered her. “Here it is, Tod.” He was at the door waiting for it, every atom of colour gone clean out of his face. Carrying it to the bed, he let its light fall full on Archie Hearn. The face was white and cold; the mouth covered with froth. “Oh, Tod! What is it that’s the matter with him?” “Hush’, Johnny! I fear he’s dying. Good Lord! to think we should have been such ignorant fools as to leave him by himself!—as not have sent for Featherstone!” We were down again in a moment. Hall stood scolding still, demanding her candle. Tod said a word that silenced her. She backed against the wall. “Don’t play your tricks on me, Mr. Todhetley.” “Go and see,” said Tod. She took the light from his hand quietly, and went up. Just then, the Doctor and Mrs. Frost, who had been walking all the way home from Sir John Whitney’s, where they had spent the evening, came in, and learnt what had happened.
- 67. Featherstone was there in no time, so to say, and shut himself into the bedroom with the Doctor and Mrs. Frost and Hall, and I don’t know how many more. Nothing could be done for Archibald Hearn: he was not quite dead, but close upon it. He was dead before any one thought of sending to Mrs. Hearn. It came to the same. Could she have come upon telegraph wires, she would still have come too late. When I look back upon that evening—and a good many years have gone by since then—nothing arises in my mind but a picture of confusion, tinged with a feeling of terrible sorrow; ay, and of horror. If a death happens in a school, it is generally kept from the pupils, as far as possible; at any rate they are not allowed to see any of its attendant stir and details. But this was different. Upon masters and boys, upon mistress and household, it came with the same startling shock. Dr. Frost said feebly that the boys ought to go up to bed, and then Blair told us to go; but the boys stayed on where they were. Hanging about the passages, stealing upstairs and peeping into the room, questioning Featherstone (when we could get the chance of coming upon him), as to whether Hearn would get well or not. No one checked us. I went in once. Mrs. Frost was alone, kneeling by the bed; I thought she must have been saying a prayer. Just then she lifted her head to look at him. As I backed away again, she began to speak aloud—and oh! what a sad tone she said it in! “The only son of his mother, and she was a widow!” There had to be an inquest. It did not come to much. The most that could be said was that he died from a kick at football. “A most unfortunate but an accidental kick,” quoth the coroner. Tod had said that he saw the kick given: that is, had seen some foot come flat down with a bang on the side of little Hearn’s head; and when Tod was asked if he recognized the foot, he replied No: boots looked very much alike, and a great many were thrust out in the skirmish, all kicking together.
- 68. Not one would own to having given it. For the matter of that, the fellow might not have been conscious of what he did. No end of thoughts glanced towards Barrington: both because he was so ferocious at the game, and that he had a spite against Hearn. “I never touched him,” said Barrington, when this leaked out; and his face and voice were boldly defiant. “It wasn’t me. I never so much as saw that Hearn was down.” And as there were others quite as brutal at football as Barrington, he was believed. We could not get over it any way. It seemed so dreadful that he should have been left alone to die. Hall was chiefly to blame for that; and it cowed her. “Look here,” said Tod to us, “I have a message for one of you. Whichever the cap fits may take it to himself. When Hearn was dying he told me to say that he forgave the fellow who kicked him.” This was the evening of the inquest-day. We had all gathered in the porch by the stone bench, and Tod took the opportunity to relate what he had not related before. He repeated every word that Hearn had said. “Did Hearn know who it was, then?” asked John Whitney. “I think so.” “Then why didn’t you ask him to name him!” “Why didn’t I ask him to name him,” repeated Tod, in a fume. “Do you suppose I thought he was going to die, Whitney?—or that the kick was to turn out a serious one? Hearn was growing big enough to fight his own battles: and I never thought but he would be up again at supper-time.” John Whitney pushed his hair back, in his quiet, thoughtful way, and said no more. He was to die, himself, the following year—but that
- 69. has nothing to do with the present matter. I was standing away at the gate after this, looking at the sunset, when Tod came up and put his arms on the top bar. “What are you gazing at, Johnny?” “At the sunset. How red it is! I was thinking that if Hearn’s up there now he is better off. It is very beautiful.” “I should not like to have been the one to send him there, though,” was Tod’s answer. “Johnny, I am certain Hearn knew who it was,” he went on in a low tone. “I am certain he thought the fellow, himself, knew, and that it had been done for the purpose. I think I know also.” “Tell us,” I said. And Tod glanced over his shoulders, to make sure no one was within hearing before he replied. “Wolfe Barrington.” “Why don’t you accuse him, Tod?” “It wouldn’t do. And I am not absolutely sure. What I saw, was this. In the rush, one of them fell: I saw his head lying on the ground. Before I could shout out to the fellows to take care, a boot with a grey trouser over it came stamping down (not kicking) on the side of the head. If ever anything was done deliberately, that stamp seemed to be; it could hardly have been chance. I know no more than that: it all passed in a moment. I didn’t see that it was Barrington. But— what other fellow is there among us who would have wilfully harmed little Hearn? It is that thought that brings conviction to me.” I looked round to where a lot of them stood at a distance. “Wolfe has got on grey trousers, too.” “That does not tell much,” returned Tod. “Half of us wear the same. Yours are grey; mine are grey. It’s just this: While I am convinced in my own mind that it was Barrington, there’s no sort of proof that it
- 70. was so, and he denies it. So it must rest, and die away. Keep counsel, Johnny.” The funeral took place from the school. All of us went to it. In the evening, Mrs. Hearn, who had been staying at the house, surprised us by coming into the tea-room. She looked very small in her black gown. Her thin cheeks were more flushed than usual, and her eyes had a great sadness in them. “I wished to say good-bye to you; and to shake hands with you before I go home,” she began, in a kind tone, and we all got up from the table to face her. “I thought you would like me to tell you that I feel sure it must have been an accident; that no harm was intended. My dear little son said this to Joseph Todhetley when he was dying—and I fancy that some prevision of death must have lain then upon his spirit and caused him to say it, though he himself might not have been quite conscious of it. He died in love and peace with all; and, if he had anything to forgive—he forgave freely. I wish to let you know that I do the same. Only try to be a little less rough at play—and God bless you all. Will you shake hands with me?” John Whitney, a true gentleman always, went up to her first, meeting her offered hand. “If it had been anything but an accident, Mrs. Hearn,” he began in tones of deep feeling: “if any one of us had done it wilfully, I think, standing to hear you now, we should shrink to the earth in our shame and contrition. You cannot regret Archibald much more than we do.” “In the midst of my grief, I know one thing: that God has taken him from a world of care to peace and happiness; I try to rest in that. Thank you all. Good-bye.” Catching her breath, she shook hands with us one by one, giving each a smile; but did not say more.
- 71. And the only one of us who did not feel her visit as it was intended, was Barrington. But he had no feeling: his body was too strong for it, his temper too fierce. He would have thrown a sneer of ridicule after her, but Whitney hissed it down. Before another day had gone over, Barrington and Tod had a row. It was about a crib. Tod could be as overbearing as Barrington when he pleased, and he was cherishing ill-feeling towards him. They went and had it out in private—but it did not come to a fight. Tod was not one to keep in matters till they rankled, and he openly told Barrington that he believed it was he who had caused Hearn’s death. Barrington denied it out-and-out; first of all swearing passionately that he had not, and then calming down to talk about it quietly. Tod felt less sure of it after that: as he confided to me in the bedroom. Dr. Frost forbid football. And the time went on. What I have further to relate may be thought a made-up story, such as we find in fiction. It is so very like a case of retribution. But it is all true, and happened as I shall put it. And somehow I never care to dwell long upon the calamity. It was as nearly as possible a year after Hearn died. Jessup was captain of the school, for John Whitney was too ill to come. Jessup was almost as rebellious as Wolfe; and the two would ridicule Blair, and call him “Baked pie” to his face. One morning, when they had given no end of trouble to old Frost over their Greek, and laid the blame upon the hot weather, the Doctor said he had a great mind to keep them in until dinner-time. However, they ate humble-pie, and were allowed to escape. Blair was taking us for a walk. Instead of keeping with the ranks, Barrington and Jessup fell out, and sat down on the gate of a field where the wheat was being carried. Blair said they might sit there if they pleased, but forbid them to cross the gate. Indeed, there was a standing interdiction against our entering
- 72. any field whilst the crops were being gathered. We went on and left them. Half-an-hour afterwards, before we got back, Barrington had been carried home, dying. Dying, as was supposed. He and Jessup had disobeyed Blair, disregarded orders, and rushed into the field, shouting and leaping like a couple of mad fellows—as the labourers afterwards said. Making for the waggon, laden high with wheat, they mounted it, and started on the horses. In some way, Barrington lost his balance, slipped over the side and the hind wheel went over him. I shall never forget the house when we got back. Jessup, in his terror, had made off for his home, running most of the way—seven miles. He was in the same boat as Wolfe, except that he escaped injury—had gone over the stile in defiance of orders, and got on the waggon. Barrington was lying in the blue-room; and Mrs. Frost, frightened out of bed, stood on the landing in her night-cap, a shawl wrapped round her loose white dressing-gown. She was ill at the time. Featherstone came striding up the road wiping his hot face. “Lord bless me!” cried Featherstone when he had looked at Wolfe and touched him. “I can’t deal with this single-handed, Dr. Frost.” The doctor had guessed that. And Roger was already away on a galloping horse, flying for another. He brought little Pink: a shrimp of a man, with a fair reputation in his profession. But the two were more accustomed to treating rustic ailments than grave cases, and Dr. Frost knew that. Evening drew on, and the dusk was gathering, when a carriage with post-horses came thundering in at the front gates, bringing Mr. Carden. They did not give to us boys the particulars of the injuries; and I don’t know them to this day. The spine was hurt; the right ankle smashed: we heard that much. Taptal, Barrington’s guardian, came over, and an uncle from London. Altogether it was a miserable time. The masters seized upon it to be doubly stern, and read us lectures
- 73. upon disobedience and rebellion—as though we had been the offenders! As to Jessup, his father handed him back again to Dr. Frost, saying that in his opinion a taste of birch would much conduce to his benefit. Barrington did not seem to suffer as keenly as some might have done; perhaps his spirits kept him up, for they were untamed. On the very day after the accident, he asked for some of the fellows to go in and sit with him, because he was dull. “By-and-by,” the doctors said. And the next day but one, Dr. Frost sent me in. The paid nurse sat at the end of the room. “Oh, it’s you, is it, Ludlow! Where’s Jessup?” “Jessup’s under punishment.” His face looked the same as ever, and that was all that could be seen of him. He lay on his back, covered over. As to the low bed, it might have been a board, to judge by its flatness. And perhaps was so. “I am very sorry about it, Barrington. We all are. Are you in much pain?” “Oh, I don’t know,” was his impatient answer. “One has to grin and bear it. The cursed idiots had stacked the wheat sloping to the sides, or it would never have happened. What do you hear about me?” “Nothing but regret that it——” “I don’t mean that stuff. Regret, indeed! regret won’t undo it. I mean as to my getting about again. Will it be ages first?” “We don’t hear a word.” “If they were to keep me here a month, Ludlow, I should go mad. Rampant. You shut up, old woman.” For the nurse had interfered, telling him he must not excite himself.
- 74. “My ankle’s hurt; but I believe it is not half as bad as a regular fracture: and my back’s bruised. Well, what’s a bruise? Nothing. Of course there’s pain and stiffness, and all that; but so there is after a bad fight, or a thrashing. And they talk about my lying here for three or four weeks! Catch me.” One thing was evident: they had not allowed Wolfe to suspect the gravity of the case. Downstairs we had an inkling, I don’t remember whence gathered, that it might possibly end in death. There was a suspicion of some internal injury that we could not get to know of; and it is said that even Mr. Carden, with all his surgical skill, could not get at it, either. Any way, the prospect of recovery for Barrington was supposed to be of the scantiest; and it threw a gloom over us. A sad mishap was to occur. Of course no one in their senses would have let Barrington learn the danger he was in; especially while there was just a chance that the peril would be surmounted. I read a book lately—I, Johnny Ludlow—where a little child met with an accident; and the first thing the people around him did, father, doctors, nurses, was to inform him that he would be a cripple for the rest of his days. That was common sense with a vengeance: and about as likely to occur in real life as that I could turn myself into a Dutchman. However, something of the kind did happen in Barrington’s case, but through inadvertence. Another uncle came over from Ireland; an old man; and in talking with Featherstone he spoke out too freely. They were outside Barrington’s door, and besides that, supposed that he was asleep. But he had awakened then; and heard more than he ought. The blue-room always seemed to have an echo in it. “So it’s all up with me, Ludlow?” I was by his bedside when he suddenly said this, in the twilight of the summer evening. He had been lying quite silent since I entered, and his face had a white, still look on it, never before noticed there. “What do you mean, Barrington?”
- 75. “None of your shamming here. I know; and so do you, Johnny Ludlow. I say, though it makes one feel queer to find the world’s slipping away. I had looked for so much jolly life in it.” “Barrington, you may get well yet; you may, indeed. Ask Pink and Featherstone, else, when they next come; ask Mr. Carden. I can’t think what idea you have been getting hold of.” “There, that’s enough,” he answered. “Don’t bother. I want to be quiet.” He shut his eyes; and the darkness grew as the minutes passed. Presently some one came into the room with a gentle step: a lady in a black-and-white gown that didn’t rustle. It was Mrs. Hearn. Barrington looked up at her. “I am going to stay with you for a day or two,” she said in a low sweet voice, bending over him and touching his forehead with her cool fingers. “I hear you have taken a dislike to the nurse: and Mrs. Frost is really too weakly just now to get about.” “She’s a sly cat,” said Barrington, alluding to the nurse, “and watches me out of the tail of her eye. Hall’s as bad. They are in league together.” “Well, they shall not come in more than I can help. I will nurse you myself.” “No; not you,” said Barrington, his face looking red and uneasy. “I’ll not trouble you.” She sat down in my chair, just pressing my hand in token of greeting. And I left them. In the ensuing days his life trembled in the balance; and even when part of the more immediate danger was surmounted, part of the worst of the pain, it was still a toss-up. Barrington had no hope whatever: I don’t think Mrs. Hearn had, either.
- 76. She hardly left him. At first he seemed to resent her presence; to wish her away; to receive unwillingly what she did for him; but, in spite of himself he grew to look round for her, and to let his hand lie in hers whenever she chose to take it. Who can tell what she said to him? Who can know how she softly and gradually awoke the better feelings within him, and won his heart from its hardness? She did do it, and that’s enough. The way was paved for her. What the accident had not done, the fear of death had. Tamed him. One evening when the sun had sunk, leaving only a fading light in the western sky, and Barrington had been watching it from his bed, he suddenly burst into tears. Mrs. Hearn busy amongst the physic bottles, was by his side in a moment. “Wolfe!” “It’s very hard to have to die.” “Hush, my dear, you are not worse: a little better. I think you may be spared; I do indeed. And—in any case—you know what I read to you this evening: that to die is gain.” “Yes, for some. I’ve never had my thoughts turned that way.” “They are turned now. That is quite enough.” “It is such a little while to have lived,” went on Barrington, after a pause. “Such a little while to have enjoyed earth. What are my few years compared with the ages that have gone by, with the ages and ages that are to come. Nothing. Not as much as a drop of water to the ocean.” “Wolfe, dear, if you live out the allotted years of man, three score and ten, what would even that be in comparison? As you say— nothing. It seems to me that our well-being or ill-being here need not much concern us: the days, whether short or long, will pass as a
- 77. dream. Eternal life lasts for ever; soon we must all be departing for it.” Wolfe made no answer. The clear sky was assuming its pale tints, shading off one into another, and his eyes were looking at them. But it was as if he saw nothing. “Listen, my dear. When Archibald died, I thought I should have died; died of grief and pain. I grieved to think how short had been his span of life on this fair earth; how cruel his fate in being taken from it so early. But, oh, Wolfe, God has shown me my mistake. I would not have him back again if I could.” Wolfe put up his hand to cover his face. Not a word spoke he. “I wish you could see things as I see them, now that they have been cleared for me,” she resumed. “It is so much better to be in heaven than on earth. We, who are here, have to battle with cares and crosses; and shall have to do so to the end. Archie has thrown-off all care. He is in happiness amidst the redeemed.” The room was growing dark. Wolfe’s face was one of intense pain. “Wolfe, dear, do not mistake me; do not think me hard if I say that you would be happier there than here. There is nothing to dread, dying in Christ. Believe me, I would not for the world have Archie back again: how could I then make sure what the eventual ending would be? You and he will know each other up there.” “Don’t,” said Wolfe. “Don’t what?” Wolfe drew her hand close to his face, and she knelt down to catch his whisper. “I killed him.” A pause: and a sort of sob in her throat. Then, drawing away her hand, she laid her cheek to his.
- 78. “My dear, I think I have known it.” “You—have—known—it?” stammered Wolfe in disbelief. “Yes. I thought it was likely. I felt nearly sure of it. Don’t let it trouble you now. Archie forgave, you know, and I forgave; and God will forgive.” “How could you come here to nurse me—knowing that?” “It made me the more anxious to come. You have no mother.” “No.” Wolfe was sobbing bitterly. “She died when I was born. I’ve never had anybody. I’ve never had a chapter read to me, or a prayer prayed.” “No, no, dear. And Archie—oh, Archie had all that. From the time he could speak, I tried to train him for heaven. It has seemed to me, since, just as though I had foreseen he would go early, and was preparing him for it.” “I never meant to kill him,” sobbed Wolfe. “I saw his head down, and I put my foot upon it without a moment’s thought. If I had taken thought, or known it would hurt him seriously, I wouldn’t have done it.” “He is better off, dear,” was all she said. “You have that comfort.” “Any way, I am paid out for it. At the best, I suppose I shall go upon crutches for life. That’s bad enough: but dying’s worse. Mrs. Hearn, I am not ready to die.” “Be you very sure God will not take you until you are ready, if you only wish and hope to be made so from your very heart,” she whispered. “I pray to Him often for you, Wolfe.” “I think you must be one of heaven’s angels,” said Wolfe, with a burst of emotion.
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