Environmental management and science
- 2. ● Environment and environmental science ● Structure and function of the environment ● Environmental and ecosystems modelling, the ecosystem concept, environmental systems and ecosystem management ● How stable are environments? ● Biodiversity ● Biosphere cyclic processes ● Environmental limits ● Environmental crisis ● Summary ● Further reading
- 3. Environment and environmental science • When environmental management makes use of science it can adopt one of two broad approaches: (1) multidisciplinary – which involves communication between various fields but without much of a breakdown of discipline boundaries; (2) interdisciplinary (even holistic) – the various fields are closely linked in an overall, coherent way.
- 6. Structure and function of the environment • Modern definitions include: the study of the structure and function of nature; the study of interactions between organisms (biotic) and their non-living (abiotic) environment; the science of the relations of organisms to their total environment (Fraser-Darling, 1963; Odum, 1975; Park, 1980).
- 9. The ecosystem • The biosphere is composed of many interacting ecosystems (ecological systems), the boundaries between which are often indistinct, taking the form of transition zones (ecotones), where organisms from adjoining ecosystems may be present together. It is possible for some organisms to be restricted to an ecotone only. Large land ecosystems or biomes (synonymous with biotic areas) are areas with a prevailing regional climax vegetation and its associated animal life, in effect regional-scale ecosystems. Biomes, such as desert biomes or grassland biomes, often mainly reflect climate, but can also be shaped by the incidence of fire, drainage, soil characteristics, grazing, trampling and so on (Watts, 1971: 186).
- 13. Environmental and ecosystems modelling, the ecosystem concept, environmental systems and ecosystem management • Once understood and monitored, environmental systems may be modelled using a variety of approaches, including theoretical, physical, analogue or computer models. A large and diverse environmental modelling field has emerged, specializing in anything from sediment transport to hydrology, groundwater, global climate change, carbon sequestration, ocean– atmosphere energy and chemical flux – and many other specialisms (Jakeman et al., 1993).
- 16. Ecosystems analysis, modelling and monitoring • Ecosystems (and environmental systems) may be analysed using systems theory, which enables complex, changing situations to be understood and predictions made. Systems theory assumes that measurable causes produce measurable effects. There have been attempts to combine ecological and economic models in systems analysis.
- 17. Environmental system and ecosystem planning and management – biogeophysical units • Ecozones
- 18. • Ecoregions and Eco districts • Coastal zone planning and management • Marine ecosystem planning and management
- 20. •River basin planning and management •Watershed/catchment planning and management •Bioregionalism
- 21. Agroecosystem analysis and management • An agroecosystem is an ecosystem modified by humans in order to obtain food or other agricultural produce. • Four agroecosystem properties were recognized by Conway (1985b): 1. Productivity 2. Stability 3. Sustainability 4. Equitability
- 22. • Landscape ecology approach-Landscape ecology is the science of studying and improving relationships between ecological processes in the environment and particular ecosystems. This is done within a variety of landscape scales, development spatial patterns, and organizational levels of research and policy. • Ekistics- concerns the science of human settlements, including regional, city, community planning and dwelling design. The study involves every kind of human settlement, with particular attention to geography, ecology, human psychology, anthropology, culture, politics, and occasionally aesthetics.
- 23. • How stable are environments? ‘Stability’ can have a number of meanings, including: lack of change in the structure of an ecosystem; resistance to perturbations; or a speedy return to steady state after disturbance (Troumbis, 1992: 252).
- 25. BIODIVERSITY • The variety of life in the world or in a particular habitat or ecosystem. • Biodiversity (biological diversity) refers to species diversity plus genetic diversity within those species.
- 27. BIOSPHERE CYCLIC PROCESSES Within the biosphere, numerous cyclic processes move and renew supplies of energy, water, chemical elements and atmospheric gases.
- 28. ENVIRONMENTAL LIMITS • The population reaching a limit may suffer gradual or sudden, limited or catastrophic collapse in numbers, a vacillation, or a cyclic boom-and-bust growth pattern. • The boundary beyond which exploitation of a natural resource will have significant deleterious effects Natural resources include land, water, air and associated living systems that comprise the biosphere. These can be classified into ecosystems.
- 30. RESOURCES• Is a source or supply from which benefit is produced. Resources are two types based upon their availability they are renewable and non renewable resource s.Typically resources are materials, energy, services, staff, knowledge, or other assets that are transformed to produce benefit and in the process may be consumed or made unavailable. Benefits of resource utilization may include increased wealth or wants, proper functioning of a system, or enhanced well being • A resource may be defined as: ‘something which meets perceived needs or wants
- 31. THEORY, PRINCIPLES AND KEY CONCEPTS • demographic transition (to marked slowing or even negative population growth) is happening more rapidly in developing countries than it did in the past in nations such as France or Russia. It is unwise to wait and see what business as usual will bring (i.e. little or no significant change in development behaviour), and better to seek stronger controls on resource use.
- 32. A rough classification of resources useful for environmental management is as follows: •those that can be safely and easily stretched by humans; • those that can be stretched with care; • those that cannot or should not be stretched
- 33. ENVIRONMENTAL CRISIS? The cause is usually identified as one or a combination of the following: people’s cavalier use of nature; over- population; misapplication of technology; faulty development ethics. What is perceived to be a crisis is subject to changing beliefs, fashion, technological ability and so on.
- 35. One may recognise several categories of perceived crisis (the following are not arranged in order of importance, do not represent a comprehensive list, nor are they all wholly separate and discrete): 1. Renewable resource depletion and degradation (especially shortfall in food production, problems with water, and energy supplies); 2. Global environmental change; 3. Pollution; 4. Nuclear or biological warfare; 5. Biodiversity loss; 6. Increasing hunger & puberty;
- 36. 7. Increasing hunger and poverty; Increasing human repression, marginalization and disempowerment; 8. Rapid, often poorly planned, urban growth; 9. Increasing population – this caused more concern in the 1970s than now; 10. Debt burden – some regions may have problems due to debt repayment or structural adjustment measures introduced to counter it.