Lecture 3 natural resources

 Life on this planet earth depends on a variety of goods and
services provided by the nature, which are known as Natural
Resources.
 Any stock or reserve that can be drawn from nature is a Natural
Resource
 Natural Resources of two Types:
• Renewable Resources- they are in exhaustive and can be
regenerated in a given span of time. E.g. Forests, wildlife,
wind, biomass, tidal, hydro energies etc.
• Non-Renewable Resources- they are exhaustive and
cannot be regenerated. E.g. Fossil fuels- coal, petroleum,
minerals, etc.

Forest Resources
Water Resources
Mineral Resources
Energy Resources
Food Resources
Land Resources

Forests is green blanket covering the Earth
About 1/3rd of the world’s land area is forested
which includes closed as well as open forests.
But the forest cover is depleting. Greatest losses
have occurred in Tropical Asia, where one third
of the forest is destroyed.
Current Forest area of India: 24.1% (FSI report
2013)

Sr.No Commercial Uses Ecological Uses
1. Wood: timber Regulates water cycle
2. Firewood Produces Oxygen
3. Pulpwood Absorbs Pollutants
4. Food items Act as a sink of CO2 (Reduce
Global Warming)
5. Gums, resins Driving Energy flow and Nutrient
Cycling
6. Fibres, canes, fodder Habitat for wildlife
7. Medicines and drugs Conservation of Soil
8. Worth: Rs.30,000/year by one
typical tree
Worth:1,00,000/year by typical tree

Over – Exploitation: Rapid & Excessive use of
forest to meet human demands
Deforestation: clearance or clearing is the
removal of a forest or stand of trees where the
land is thereafter converted to a non-forest use.

Due to wood cutting & large scale logging for
raw material
Deforestation due to road construction
Forest clearing to convert it to Agricultural Land
to meet food demands
Encroachment of Forests
Heavy grazing
Mining activities
Hydropower projects

Fuel Requirement
Raw material for industries
Shifting cultivation
Development projects –dams
Growing food needs
Overgrazing
Forest fires

Existence of Species is affected- Natural Habitat
Biodiversity is lost
Hydrological cycle affected
Soil erosion
In hilly areas – Landslides
Increase in Carbon levels…….Global
Warming………

Advantages Disadvantages
Checks Floods, famine Loss of Forest area
Generate Electricity Large land under submergence
Reduce water & power shortage Relocation of many tribal, communities,
people, farmers.
Provide Irrigation water to low areas Local Riots, abuse
Promote fisheries Flash Floods
Employment Seismic changes
Siltation & Sedimentation Problem
Micro-Climate Change
Breeding of Vector & Spread of disease
Society now moving towards construction of small dams or mini- hydal projects.

Sardar Sarovar Dam
Tehri Dam
Silent Valley
Chipko Movement

 Water is known as LIFE
 Nearly 80% of body composition
 Water is a chemical substance, a liquid at ambient
conditions, often co-exists on earth with its solid state i.e
ice, and gaseous state i.e water vapor or steam.
 Properties:
• Universal solvent- so it can be nutrient carrier,
• High surface tension- so it can rise easily at great heights,
• Anomalous expansion- it freezes, it expands instead of
contacting.

 World oceans cover about 3/4th of earth’s surface.
 Fresh water constitutes a very small proportion of this enormous quantity.
 About 2.7 % of the total water available on the earth is fresh water of which
about 79 % lies frozen in polar regions and another 20% is present as
ground water.
 The rest is available in lakes, rivers, atmosphere, moisture, soil and vegetation

Sr.No Uses
1. Agriculture-
2. Drinking
3. Washing
4. Transportation
5. Chemical uses
6. Fire Extinguish
7. Recreation
8. Water Industry
9. Food Processing
10. Industrial Application

Water
Rain
Ground
Water
Aquifer
Confined Unconfined
Surface
Water
Pond, Lake, Rivers,
Streams, Artificial
Reservoirs
Ice Caps,
Glaciers

 Water which percolates or infiltrates down in the
ground
 Huge source of fresh water.
 Layer of sediment or rock that is highly permeable
and contains water is an AQUIFER
• Confined- Which are sandwiched between two
impermeable layers of Rock/Sediments, Recharged
where it intersects the land surface and
• Unconfined aquifers- which are overlaid by permeable
earth materials, recharged by water seeping down form
surface.

 Subsidence
• When groundwater withdrawal is more than its recharge
rate, the sediments in the aquifer get compacted, a
phenomenon known as “groundwater subsidence”.
 Lower of Water Table
• Mining of water is done extensively in arid & semi-arid
regions, which leads to lowering of water table.
 Water Logging
• When irrigation is done with Brackish water, water table
level increases leading to logging
 Water Pollution
• Discharge and dumping of waste in water resources

Heavy Rainfall causes floods in low-lying areas
coastal areas.
Prolonged downpour cause overflow of rivers,
lakes leading to floods.
Anthropogenic Activities- Deforestation,
overgrazing, mining, rapid industrialization.
It is very regular feature in some North Eastern
Parts of India & Bangladesh

When annual rainfall is below normal and less
than evaporation, drought conditions are
created.
Meteorological Phenomenon
Anthropogenic Causes:Grazing, deforestation,
mining.
Leads to desertification
Proper crop plantation is a
remedial measure.

 Unequal distribution is the major cause
 Cauvery water dispute:
• Cauvery River is contention between Karnataka & Tamil Nadu,
and the problem is hundred years old.
• The upstream is in Karnataka & downstream is in TN.
• The TN people wants water-use regulated in Upstream,
whereas the Karnataka people claims primacy over it.
• June 2, 1990- Cauvery Water Dispute Tribunal was set up.
 Indus the water treaty-
• established in 1960
• The Jhelum ,Chenab & Indus itself given to Pakistan while The
Sutlej, Ravi & Beas to India
 Sutlej-Yamuna link canal dispute
• Issue between Punjab & Haryana

Minerals are naturally occurring, inorganic,
crystalline solids having a definite chemical
composition & characteristics properties.
Composition of Mineral:
• Silicon, oxygen, iron, magnessium, calcium, aluminium,
etc.
• Some common minerals like quartz, feldspar, biolite,
dolomite, calcite, laterite, etc.

Minerals classified based on their properties are
of two types:
• Metallic
• Non-Metallic
Minerals are also classified as :
• Critical – Essential for economy of Nation
e.g. Iron, Aluminium, Gold, Copper, etc.
• Strategic – Essential for defence of Country
e.g. Manganese, Cobalt, Platinum, Chromium, etc.

Sr.
No
Mineral Uses
1. Aluminium Packaging food items, transportation, utensils, electronics
2. Chromium For making high strength steel alloys, textile/tanning ind.
3. Copper Electric & Electronic Goods, building, construction, vessels
4. Iron Heavy machinery, steel production, transportation means
5. Lead Gasoline, car batteries, paints, ammunition
6. Manganese Making high strength, heat resistance steel alloys
7. Gold Ornaments, medical use, use in aerospace
8. Silver Jewellery, photography, electronics
9. Nickel Batteries
10. Platinum Automobiles, catalytic convertors, jewellery, medical use

Sr.
No
Mineral Uses
1. Silicate Sand & gravel for construction, bricks, paving, etc
2. Limestone Used for concrete, building stone, used in agriculture for
neutralizing acid soils, used in cement industry.
3. Gypsum Used in plaster wall-board, in agriculture
4. Potash,
phosphorite
Used in fertilizers
5. Sulphur
pyrites
Used in medicine, car battery, industry

Mining
Surface- shallow
Deposits
Open – Pit Mining –
Machines dig holes
Dredging-chained
buckets & draglines are
used
Strip Mining
Ore is stripped by using
bulldozers, power
shovels& stripping
wheels
Sub-surface- deep
deposits

Devegetation and defacing of landscape
Subsidence of land
Ground water contamination
Air pollution
Surface water pollution
Occupational health hazards

Jaduguda Uranium mines: Jharkhand
Jharia coal mines: Jharkhand
Sukinda Chromite mines: Orissa
Kudremukh iron ore mines: Karnataka
East coast bauxite mines: Orissa
North eastern Coal fields: Assam

Reduce, reuse, recycle
New and improved mining technologies
MICROBIAL LEACHING TECHNIQUE
Restoration of mined lands
Revegetation and stabilization.

 The most important natural resource, upon which all
human activity is based since time immemorial, is land.
 Land resource is our basic resource.
 Throughout history, we have drawn most of our
sustenance and much of our fuel, clothing and shelter
from the land.
 It is useful to us as a source of food, as a place to live,
work and play. It is a productive economic factor in
agriculture, forestry, grazing, fishing and mining.
 It is considered as a foundation of social prestige and is
the basis of wealth and political power.

 Out of the total land area, as many as 175 million hectares suffer
from degradation.
 Land degradation is caused largely by soil erosion, but also by
water logging and excessive salinity.
 Most serious threat deforestation.
 The exponentially growing population ----immense pressure
 The high degree of degradation of existing land resources, the
changing climate and increasing diversion of land from
agricultural to non-agricultural uses have aggravated the problem.
 The productivity of land has suffered to a great extent, beyond
repair
 India, being a large agrarian society, has, therefore, an enormous
task to meet the growing demands for food, fuel, fiber together
with environmental security for its people in the coming years.

Soil Erosion
• Water induced erosion
• Wind induced erosion
Water Logging & Salinity
Desertification
Landslides

Means wearing of soil
Defined as “the movement of soil components,
especially surface-litter and top soil from one
place to another.”
It leads to loss of fertile soil layer

Two types of Soil Erosion:
• Normal or geologic Erosion: Removal of top soil by
natural processes- physical, biological & hydrological
activities
• Accelerated Erosion : mainly caused by anthropogenic
activities like overgrazing, deforestation, mining.
Two factors :
• Climatic Agents- Water & wind
• Biotic Agents- Excessive grazing, deforestation, mining.

 Sheet Erosion: Uniform removal of thin layer of soil
from large surface area.
 Rill Erosion: Due to rainfall finger like grooves or rills
are formed, it is called rill erosion
 Gully Erosion: it is prominent in heavy rainfall, where
deeper cavities or gullies are formed of U /V shaped.
 Slip Erosion: this occurs due to heavy rainfall on slopes
of hills & mountains
 Stream bank Erosion :in rainy season, when fast
running streams take a turn in some direction, they cut
the soil and make caves in the banks.

Saltation: This occurs due to direct pressure of
stormy wind and the soil particles of 1-1.5 mm
diameter move up in vertical direction.
Suspension: Here fine soil particles (less than 1
mm dia) which are suspended in air are picked
and taken away to distant places.
 Surface Creep: Here larger particles (5-10 mm
dia) creep over the soil surface along with wind.

Conservational till farming
Contour farming
Terracing
Strip Cropping
Alley Cropping
Wind breaks or Shelterbelts

 Tillage is the agricultural preparation of the soil by
mechanical agitation of various types, such as digging,
stirring, and overturning.
 Examples of human-powered tilling methods using hand
tools include shoveling, picking, mattock work, hoeing, and
raking.
 Examples of draft-animal-powered or mechanized work
include ploughing, etc

 On gentle slopes horizontal rows of plants
 Helps slow down run off

Done on steep slopes
Extremely efficient to prevent run off.
Good in high rainfall areas

Alternate strips of crops with grasses or
grass legume mixture
Run off is retained by strip cover
Also helps nitrogen fixing

Alley Cropping is planting rows of trees at wide spacing with a
companion crop grown in the alleyways between the rows. Alley
cropping can diversify farm income, improve crop production
and provide protection and conservation benefits to crops.

It is a plantation
usually made up of one
or more rows of trees
or shrubs planted in
such a manner as to
provide shelter from
the wind and to protect
soil from erosion. They
are commonly planted
around the edges of
fields on farms.

Result of excessive irrigation
Pore spaces filled with water
Roots cannot breath
Make continuous column with water
When evaporates leaves behind a white crust of
salt
Extremely high sodium quantity.
Precious LAND RESOURCE IS WASTED

In this huge masses of land slide down
destroying anything in its path.
Various developmental activities like large dams,
reservoirs, construction of roads etc require
large scale deforestation.
This increases chances of landslides

 Process of conversion of productive land to arid or
semi arid lands
 10-25% drop in productivity in moderate desertification
 More than 50% in serious desertification
 Creates gullies or sand dunes
 Leads to depletion of ground water, salinization
 Causes are deforestation, overgrazing and mining
 Areas include Saharan Africa, Middle East, Western
Asia, parts of central and south America.
 Domino effect

 Food is any substance consumed to provide nutritional support
for the body.
 It is usually of plant or animal origin, and contains essential
nutrients, such as carbohydrates, fats, proteins, vitamins, or
mineral.
 Out of thousands of edible plants and animals around 3 dozen
types form major food of humans
 Agriculture is the source of majority of food components

 Wheat
 Rice
 Maize
 Potato
 Barley
 Oats
 Cassava
 Sweet potato
 Sugarcane
 Pulses
 Millet
 Sorghum
 Vegetables
 Meat
 Milk
 Fish

 Minimum caloric intake should be 2500 calories /day
 If less than 90% of this amount: Undernourished
 If less than 80% : Seriously undernourished
 Deficiency or lack of nutrition causes:
MALNUTRITION.
 Last 50 years food production…tripled
 Population growth rate also high…..
 Every year 40 million people die of MALNUTRITION
and UNDERNOURISHMENT
 300 million Indians are UNDERNOURISHED
 Food production in 64 developing countries….lagging
behind population growth rate……

Staple foods:
Agriculture
Meat, Milk and products:
Livestock

Agricultural improvement by: new
machines, hybrid technology, improved
varieties, excessive fertilizers, irrigation etc
Milk, poultry and meat products:
Hybridisation techniques, improved
sanitary conditions, disease control,
medicines, OVERGRAZING

 Grazing on grasslands or pastures.
 Available areas under decline
 Exceed the CARRYING CAPACITY
Impacts:
 Land degradation
 Soil erosion
 Loss of Useful Species

 Necessary as it’s the major source of food
 It dates back to as long as humans exist
 Hunter gatherer-----------civilized by agriculture
 Slash and burn traditional technique used.

 Traditional agriculture and its impacts:
Forest clearing , Soil erosion and Depletion of
nutrients
 Modern Agriculture and its Impacts:
Impacts of HYV(high yield varieties)
Fertilizer related problems
Pesticide related problems
Water logging
Salinity problem

 Deforestation due to Slash and burn technique
 Clearing of forests for new land area
 Depletion of Nutrients

Impacts of High yield
varieties
Encourage MONOCULTURE
These crops demands controlled
irrigation.
These crop should be irrigated
at right time as per the schedule
and in right quantity.
Most of the HYV seeds are
dwarf varieties.
They need higher doses of
fertilizer.
HYV crops are highly
susceptible to pests.

 N, P, K are essential macronutrients
 Highly used to get boost in production
 They cause MICRONUTRIENT IMBALANCE
Eg: Punjab and Haryana soils suffer from severe deficiency of
Zinc.
 Nitrates pollute ground water. Conc more than 25
mg/l….causes Blue Baby Syndrome
 Eutrophication

•Development
of Resistant
varieties: Super
pests
•Death of non
target organisms
•Biological
magnification

Over irrigation is the major cause
Inadequate drainage leads to high
water column
Pore spaces drenched with water
No adequate gaseous exchange

1/3rd of cultivable land affected by salts caused by
excess irrigation
Accumulation of salts like NaCl, sodium sulphate,
calcium and magnesium chloride
High electrical conductivity and high sodium
percentage
Water evaporates and leaves behind a white crust of
salt
Punjab and Haryana face problem

Lecture 3 natural resources

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Lecture 3 natural resources