This document discusses natural resources including renewable resources like soil, water and air and non-renewable resources like minerals and fossil fuels. It then focuses on forest resources, highlighting that forests cover about 1/3 of the world's land area and provide commercial and environmental benefits. The document also discusses overexploitation of forests through activities like shifting cultivation, fuel collection and infrastructure development. It notes the effects of deforestation and describes forest conservation methods.

1. ME 6403- Environmental Science and
Engineering
NATURAL RESOURCES
Prepared by
V.NaveenPrabhu
Assistant Professor
Sri Eshwar college of Engineering
Coimbatore

3. 1. Renewable resources:
These resources are capable of being regenerated by
ecological processes within a reasonable time period. They
have the potential to renew themselves.
Ex. Soil, water, air ,wildlife, natural vegetation.
i) Continuous resources:
These resources are continuously renewed.
Ex. Solar energy, wind, tidal energy.
ii) Extrinsic resources:
These resources are prone to degradation, yet are
available continuously if well managed.
Ex. Human skills, institutions, management abilities.
3

4. 2. Non-renewable resources:
These resources are not capable of being
regenerated by ecological processes.
Ex. Minerals, coal oil, natural gas, ground
water.
FOREST RESOURCES
Forests are one of the most important
resources of the world. Apart from having high
commercial importance they provide high
environmental services also. They act as a
blanket on the surface of the earth.
Around 1/3rd of world land area was
found to be forests. 1/5th of world forests were
found in Brazil and 6-7% was in Canada and
USA
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5. 5
USES OF FOREST
I. Commercial uses: Forests provide timber, fire
wood, food material, resin, gum, non edible oils,
drugs, medicine, rubber, fibers, bamboo and
many other important items.
II. Aesthetic value: Serve as gene reserve of
important species.
i) Tribals utilize bamboo and wild grass for
erecting the huts to reside & for making
other products like mats, baskets, cots
etc.,
ii) Fruits, leaves, seeds, roots are used as food
by tribals & poor.

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IV. Ecological uses:
 Production of Oxygen: Photosynthesis – earth’s
lungs
 Reducing global warming – sink for carbon di
oxide
 Wild life habitat – 7 million species in tropical
forests alone
 Regulation of hydrological cycle – prevent
surface run off – giant sponges – 50-80%
moisture
 Soil conservation – hold solid particles tightly and
prevent soil erosion – wind breaks
 Pollution moderators: absorb toxic gases, purify
air and reduce noise pollution.

7. Photosynthesis
global warming
Wild life habitat
hydrological cycle
Soil conservation
Pollution moderators
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8. OVER EXPLOITATION OF FORESTS:
Human beings depend heavily on forests for
food, shelter, wood, fuel and medicine with
growing civilization etc. shoot up resulting
in large scale mining, road building and
clearing of forests.
Excessive use of charcoal, fuel wood,
expansion of urban, agricultural, industrial
areas and overgrazing have lead to over
exploitation and rapid degradation of
forests.
Causes for over exploitation:
Increasing agricultural production.
8

9. Effects (or) Consequences of Over Exploitation
 Over exploitation of the forest resources led to
migration of the farmers.
 Marine populations will go into extinction.
 Dumping of wastes into land, water and air has
become a severe problem.
 Countless plant species and animals are endangered.
 The tropical forests are destroyed at very fast rate.
 Environmental damage caused by over-exploitation is
heavy.
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DEFORESTATION:
Deforestation is the clearance of naturally
occurring forests by logging and burning.
(Logging is the process in which certain trees are
cut down by a machine)
The total forest area of the world in
 1900 A.D. – 7000 million hectares
 1975 A.D. – 2900 million hectares
 2000A.D. – 2300 million hectares

11. MAJOR CAUSES OF DEFORESTATION:
 Shifting of Cultivation
 Fuel requirement
 Raw materials for industrial use
 Developmental projects
 Growing food needs
 Overgrazing

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What is overgrazing?
It is a process of “eating away the forest
vegetation without giving it a chance to regenerate.
CONSEQUENCES OF DEFORESTATION
 Global warming
 Biodiversity is lost along with that genetic diversity
 Hilly regions are made prone to landslides
Soil erosion and loss of soil fertility
 Hydrological cycle is affected
(loss of rainfall, flood, drought etc)
 Global warming( increasing the CO2 level)

13. Methods of conservation of forests
 New plants of more or less of the same variety should be
planted to replace the trees cut down for timber.
 Use of wood for fuel should be discouraged.
 Forest pests can be controlled by spraying pesticides by
using aeroplanes.
 Forest fire must be controlled by modern techniques.
 Overgrazing by cattle must be controlled.
 Steps should be taken by the government to discourage the
migration of people into the islands from mainland.
 Education and awareness programmes must be conducted.
 Strict implementation of law of Forest Conservation Act.
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TIMBER EXTRACTION AND MINING:
The major activities in forest area are
 Timber extraction
 Mining
The important effects of timber extraction are
 Thinning of forests
 Loss of biodiversity, particularly tree breeding
species
 Soil erosion and loss of soil fertility
 Migration of tribal people from one place to another
in search of new forest
Uses of timber:
 Raw materials for various wood based industries like
paper, composite wood, furniture, etc.,
 Used for various developmental activities like
railways, boats, road construction etc.,

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MINING:
Mining is a process of removing ores from area which is
very much below the ground level. Mining is done for the
extraction of several minerals of metals like Fe, Mn, Au, Ag,
etc. The minerals are especially found in thick forests.
An ore is a type of rock that contains sufficient minerals with
important elements including metals that can be
economically extracted from the rock. The ores are
extracted from the earth through mining; they are then
refined (often via smelting) to extract the valuable element,
or elements.
Mining can be carried out in two ways
 Surface mining
It involves mining of mineral from the shallow deposits.
 Underground mining
It involves mining of minerals from deep deposits.
The effects of under ground mining on forest reserves is
comparatively less than that of surface mining

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Environmental Impacts Of Over Extraction Of Mineral
Resources:
Deforestation takes place due to removal of vegetation
covers.
The stacking of over burden and building of spoil banks
creates problems of landslides
Under ground fire in coalmines is a hazard that is difficult
to control
Mining and ore processing normally causes air pollution
and water pollution
The acid water generated in coalmines can pose a serious
problem of water pollution,
Deeper excavation of ground causes lowering of water
table, which leads to drying of wells or sea water intrusion
The disposal of waste material produced after
concentrations of ore create increase concentration of
heavy metals and toxic elements

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DAMS – BENEFITS AND ENV. PROBLEMS
Dams are the massive artificial structures built across
the river to store water for many beneficial purpose.
India has more than 1600 large dams. River valley projects
with big dams are considered to play a key role in the
development of a country. India has large number of river
valley projects.
– Provides large scale employment of tribal people
– Contribute for economic uplift and growth
– Help in checking flood
– Generate electricity
– Reduce power and water shortage
– Provide irrigation water
– Provide drinking water to remote areas

18. Effects of dam on forest:
 Forests have been cleared for executing river valley
projects.
 Forest is also cleared for residential accommodation, office
buildings, storing materials, laying roads, etc.,
 Hydroelectric projects leads to loss of forest in recent
years.
 Construction of dams under these projects led to killing of
wild animals and destroying aquatic life.
 Hydroelectric projects provide opportunities for the spread
of water borne diseases.
 The big river valley projects also cause water logging
which leads to salinity and inturn reduces the fertility of the
land.
 Example: Narmada Sagar project - It has submerged 3.5
lakh hectares of forest comprising teak and bamboo trees.
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19. Effect of dam on tribal people:
 Displacement of tribal people
 The displacement and cultural change affects the tribal
people both mentally and physically. They do not
accommodate the modern food habits and life styles.
 Tribal people are ill- treated by the modern society.
 Many of the displaced people were not recognized and
resettled or compensated.
 Tribal people and their culture cannot be questioned and
destroyed.
 Generally, the body conditions of the tribal people will not
suit with the new areas and hence they will be affected by
many diseases.
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Environmental problems:
The environmental problems can be
at upstream as well as downstream Level
Displacement of tribal people
Loss of flora and fauna
Stagnation and water logging near reservoir
Micro climatic changes
Breeding of disease vectors
Water logging and salinity due to over
irrigation
Salt water intrusion at river mouth
Loss of fertility due to sediment deposits

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WATER RESOURCES
Around 2/3 of world surface is covered with water.
Out of the total available water 75% is used for agriculture,
20% for industrial usage.
Ground water:
9.86% of fresh water is ground water and it is 35-50% greater
than surface water.
 AQUIFER: The layer of soil which is permeable has the
ability to store water is called an aquifer. It is generally made
up of gravel, sand etc.
 Unconfined aquifer: it is covered by permeable layer. The
recharge of this layer is by rainfall or snowmelt.
 Confined aquifer: sandwiched between impermeable
layers. The recharge is through unconfined aquifer layers.

22. Hydrological cycle:
“The process of evaporation, condensation
and transpiration is called hydrological
cycle”.
Hydrological cycle involves the
following steps.
Evaporation: Surfaces of terrestrial
organisms loose water.
Condensation and precipitation:
Precipitation occurs due to the condensation
of water from a gaseous state in the
atmosphere and falls to earth. 22

23. Surface Water:
1. Standing Water Bodies. A) Lakes B)
Reservoirs C) Estuaries
i) oligotropic lakes- deep, clean deficient in
nutrients,
ii) Eutrophic lakes- turbid with more nutrients
iii)Dystrophic lakes–shallow & coloured lakes
low pH.
2. Flowing Water Bodies i) streams ii) rivers
3.Under Ground Water
Aquifer – A layer of highly permeable rock
containing water is called an aquifer. 23

24. Uses of water -Different Types
Consumptive use: water is completely utilized
and it is not reused. Ex. In domestic application.
Non-Consumptive use: Water is not
completely utilized and it is reused. Ex. Hydro
power plant.
Other important uses of water:
 Used for domestic purposes. Ex. Drinking, cooking.
 Used for commercial purposes. Ex. Hotels.
 Used for irrigation ( 60-70%)
 Used for industrial operations (20-30%). Ex. refineries.
 Used for moderating climate and diluting pollutants.
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Over utilization of ground water:
Over utilization of water leads to
 Rapid depletion of water resources,
 Ground subsidence,
 Lowering of water table
 Water logging.

26. Effects of over utilization of ground water:
Reasons: Economic development, rapid
industrial growth and population explosion.
The use of ground water and surface water
rates which are higher than that of recharge
ultimately leads to
Water scarcity
Water logging
Salination
Alkalization
water pollution or contamination

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Surface water:
When evaporation and transpiration rates are lower than
the rainfall, surface water body like lake, river, pond, streams
etc. are formed.
Flood:
Over flow of water, whenever the water in flow is greater
than the carrying capacity of the channels, flood occurs.
Causes:
 Heavy rainfall,
 Snow melt,
 Sudden release of water from dams.
 Deforestation, overgrazing, mining increases water run off
 Removal of dense forests from hilly regions
Effects:
 Submerges the flooded area
 Loss of soil fertility due to soil erosion
 Extinction of civilization at costal area

28. Flood management:
Dams and reservoirs can be constructed.
Channel management and embankments
also control the floods.
Encroachment of flood ways should be
banned.
Flood hazard may also be reduced by
forecasting or flood warning.
Flood may also be reduced by reduction of
runoff by increasing infiltration through
appropriate afforestation.
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Drought
Drought is a period or condition of unusual dry weather
within a geographic area where rainfall is normally present.
Drought usually results in a water shortage that seriously
interferes with human activity
Types:
Meteorological drought
Hydrological drought
Agricultural drought
Meteorological Drought
Meteorological drought is the amount of dryness and the
duration of the dry period. Atmospheric conditions that result in
deficiencies of precipitation change from area to area.

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Agricultural Drought
Agricultural drought mainly effects food production and
farming. Agricultural drought and precipitation shortages bring soil
water deficits, reduced ground water or reservoir levels, and so on.
Deficient topsoil moisture at planting may stop germination, leading
to low plant populations.
Hydrological Drought
Hydrological drought is associated with the effects of
periods of precipitation shortages on water supply. Water in
hydrologic storage systems such as reservoirs and rivers are often
used for multiple purposes such as flood control, irrigation,
recreation, navigation, hydropower, and wildlife habitat. Competition
for water in these storage systems escalates during drought and
conflicts between water users increase significantly.

31. Effects of drought
Drought causes hunger, malnutrition and
scarcity of drinking water.
Drought causes crop failures leading to
shortage of food
Drought affects livestock populations.
Drought affects agro-based industries.
Drought causes degradation of natural
resources.
Drought leads to large migration of people.
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32. Drought Management
Rain water harvesting programme is the
fruitful method to conserve more water.
Improving ground water level by
constructing reservoirs.
Using modern irrigation technology ( drip
irrigation)
Afforestation activities also improves the
potential of water.
Mixed cropping and dry farming minimize
the risks of crop failures in dry area.
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Conflicts over water
International conflicts
• India and Pakistan-Indus river
• Mexico and US- Colorado river
• Iran and iraq- Shatt-al-arab river
• India and Bangladesh-Bramhaputra river
National conflicts
• Cauvery Water- Karnataka and Tamilnadu
• Krishna water- Karnataka and Andhrapradesh
• Siruvani water- Tamilnadu and Kerala

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Mineral resources
Mineral: Any naturally occurring chemical element
or compound that have been formed through inorganic
processes. Minerals are exhaustible, non-renewable
resources found in the earth’s crust.
 More than 3,000 mineral species are known, most of
which are characterized by definite chemical
composition, crystalline structure, and physical
properties.
 India has large reserves of iron, manganese, lime
stone, dolomite, silica, and mica but has little reserves
of copper, gold, silver, lead and phosphate.

35. Formation of mineral deposits by biological processes:
 biological decomposition of dead animals and organic matters.
 Cooling of molten rock - lava from volcano.
 Evaporation of sea water.
 Due to oxidation and reduction reaction inside the earth.
Classification of Mineral Resources:
 Identified resources: location existence are known.
 Undiscovered resources: specific locations, quantity - unknown
 Reserves: from which a usable minerals can be extracted.
Based on composition:
1. Metallic minerals: Cu, Zn,Fe. 2. Nonmetallic minerals- Quartz.
Based on usage:
1.Critical minerals: Gold. Cu. 2.Strategic (defence) – Mn, Co,
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Uses of Minerals
Metals are classified into various category
 Precious metals: gold, silver, and the platinum
 Steel industry metals: iron, nickel, cobalt, titanium,
vanadium, chromium;
 Base metals: copper, lead, tin, and zinc; magnesium
and aluminum
 Nuclear metals: uranium, radium, and thorium;
 Specialty metals: lithium, germanium, gallium, and
arsenic.
 Industrial minerals: quartz, salt, potash, asbestos, talc,
feldspar, sulphur & phosphates

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 Many minerals are essential for growth and
functioning of the living organisms.
 Number of minerals used in industries, production of
consumer’s goods, agriculture inputs, hospitals and
defense and research equipments
 Construction materials include sand, gravel,
aggregates, brick clays and limestone, cement.
 Gemstones include diamonds, rubies, sapphires, and
emeralds.

38. METALS YEAR OF DEPLETION
Aluminum  31
Chromium  95
Copper  21
Iron  93
Lead  21
Manganese  46
Mercury  13
Molybdenum  34
Nickel  53
Silver  13
Tin  15
Tungsten  28
Zinc  18 38
METALS AND THEIR EXPECTED YEAR OF DEPLETION

39. 39
Some Major Minerals of India
 Coal and lignite: West Bengal, Jharkhand, Orissa, M.P,
A.P
 Uranium (Pitchblende or Uranite ore): Jharkhand,
Andhra Pradesh (Nellore, Nalgonda),Meghalaya,
Rajasthan (Ajmer).
 Aluminum (Bauxite ore): Jharkhand, West Bengal,
Maharashtra, M.P, Tamilnadu.
 Iron (hematite and magnetite ore): Jharkhand, Orissa,
M.P, A.P, Tamilnadu,Karnataka, Maharashtra and Goa.
 Copper (Copper Pyrites): Rajasthan, Bihar, Jharkhand,
Karnataka, M.P, West Bengal, Andhra Pradesh and
Uttaranchal.

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Environmental Effects caused by mining activities are
 De-vegetation /Loss of biodiversity
 Subsidence of land: Subsidence of mining areas often results in
tilting of buildings, cracks in houses, buckling of roads, bending
of rail tracks and leaking of gas from cracked pipelines leading to
serious disasters.
 Groundwater Pollution: Sulphur, usually present as an impurity in
many ores is known to get converted into sulphuric acid through
microbial action, thereby making the water acidic.
 Surface water pollution: The acid mine drainage often
contaminates the nearby streams and lakes. The acidic water is
detrimental to many forms of aquatic life. Heavy metal pollution
of water bodies near the mining areas is a common feature
creating health hazards.

41. 41
 Air pollution: In order to separate and purify the metal
from other impurities in the ore, smelting is done
which emits enormous quantities of air pollutants
damaging the vegetation nearby and has serious
environmental health impacts. The suspended
particulate matter (SPM), Sox, arsenic particles,
cadmium, lead etc.
 Health Hazards: Most of the miners suffer from
various respiratory and skin diseases due to constant
exposure to the suspended particulate matter and toxic
substances.

42. Effects of over exploitation of Mineral resources
 Rapid depletion of mineral deposits.
 Leads to wastage and dissemination of mineral
deposits.
 Causes environmental pollution.
 Needs heavy energy requirement.
Management of Mineral resources
 The efficient use and protection of mineral resources.
 Modernization of the mining industries.
 Reuse and Recycling of the metals.
 Search for new deposit.
 Environmental impacts can be minimized by adopting
eco-friendly mining technology.
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43. 43
Food resources
PROBLEMS FACED BY FOOD RESOURCES
Overgrazing
 Land degradation
 Soil erosion
 Loss of useful species
Modern agriculture
 High yield variety crops
 Micronutrients imbalance
 Nitrate pollution
 Eutrophication
 Pesticide related problems
 Water logging
 Salinity

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Overgrazing:
Grass is a good binder of soil.
Overgrazing leads to loss of vegetal cover. Soil
gets compacted because of excess evaporation
of water. Water cannot percolate into the soil.
Roots cannot pass into the soil. Soil texture is
lost, fertility is lost and at last leads to soil
erosion.
Soil erosion:
When uncovered, waterless soil is acted
upon by heavy wind and rainfall soil erosion
results. This leads to loss of useful species and
many nutrients. Overgrazing leads to
replacement of thorny plants in the place of
leafy, fruit bearing plants.

45. High yield crop variety:
The usage of high yield crop variety leads
to monoculture – same type of crop is planted
on large scale. In case of any pathogenic
effects, due to exactly uniform condition in the
crop field, total loss is encountered.
Micronutrient imbalance:
Excessive use of macronutrients causes
micronutrients imbalance. Ex. Zinc deficiency
faced in Punjab and Haryana

46. AGRICULTURE
Agriculture is an art, science and industry of managing the
growth of plants and animals for human use.
Types:
1.Traditional Agriculture: It involves a small plot, simple tools,
surface water, organic fertilizers and a mix of crops.
Effects: a) Deforestation, b) Soil erosion c) Loss of nutrients.
2.Modern Agriculture: It makes use of hybrid seeds of single crop
variety, high- tech equipments, lot of fertilizers, pesticides and
water to produce large amount of single crops
Effects: a) Problems in using Fertilizer
i) Micronutrient imbalance
ii) Blue Baby Syndrome
iii) Eutrophication:
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47. b)Problems in using pesticides: In order to
improve the crop yield, lot of pesticides are
used in the agriculture.
First generation pesticides: S, As, Pb, or Hg
are used to kill the pests.
Second generation pesticides: DDT
(dichlorodiphenyltrichloromethane)
i)Death of non-target organisms
ii) Producing new pests
iii)Bio-magnification
iv) Risk of cancer
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48. C. Water logging: Water logging is the land where water stand for
most of the year.
problems in water logging: During water-logged conditions, pore-
voids in the soil get filled with water and the soil-air gets depleted.
In such a condition the roots of the plants do not get adequate air for
respiration. So, mechanical strength of the soil decreases and crop
yield falls.
Causes of water logging:
Excessive water supply to the croplands.
Heavy rain.
Poor drainage.
Remedy
Preventing excessive irrigation, sub-surface drainage technology
and bio-drainage by trees like Eucalyptus tree are some method of
preventing water logging.
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49. D. Salinity:
The water, not absorbed by the soil, undergo evaporation
leaving behind a thin layer of dissolved salts in the topsoil. This
process of accumulation of salts (NaCl, CaCl2, MgCl2 ) is called
salinity of the soil. The pH of the water exceeds 8.0(alkaline)
Problems in salinity
Most of the water, used for irrigation comes only from canal or
ground, which unlike rainwater contains dissolved salts. Under
dry climates, the water gets evaporated leaving behind the salt in
the upper portion of the soil. Due to salinity, the soil becomes
alkaline and crop yield decreases.
Remedy:
The salt deposit is removed by flushing them out by applying
more good quality water to such soils and using sub- surface
drainage system.
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Renewable energy is energy which comes from natural
resources such as sunlight, wind, rain, tides, and geothermal heat,
which are renewable (naturally replenished)
Non-renewable resource is a natural resource which cannot be
produced, grown, generated, or used on a scale which can sustain
its consumption rate
Fossil fuels (such as coal, petroleum and natural gas) and nuclear
power (uranium) are examples
ENERGY RESOURCES

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Wind power
Airflows can be used to run wind turbines

52. Hydropower
Energy in water can be harnessed and used. Since water is about
800 times denser than air even a slow flowing stream of water, or
moderate sea swell, can yield considerable amounts of energy
52

53. Solar energy
Solar energy is the energy derived from the sun through the form of
solar radiation. Solar powered electrical generation relies on
photovoltaics and heat engines
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54. 54
Geothermal energy
Geothermal energy is energy obtained by tapping the heat of
the earth itself, both from kilometers deep into the Earth's crust in
some places of the globe or from some meters in geothermal heat
pump in all the places of the planet

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Alternative energy
Energy derived from sources that do not use up natural
resources or harm the environment.
Coal as an alternative to wood
Petroleum as an alternative to whale oil
Alcohol as an alternative to fossil fuels
Coal gasification as an alternative to
petroleum.

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Biofuel
Liquid biofuel is usually either bioalcohol such as bioethanol or
an oil such as biodiesel.
Bioethanol is an alcohol made by fermenting the sugar
components of plant materials and it is made mostly from sugar
and starch crops.

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LAND RESOURCE
Land is critically important national resource
which supports all living organisms including
plants and animals. The soil profile of land
determines its ability to serve socio-economic
needs.
 It has been estimated that more than 5000 million
tones of top soil is eroded annually along with 5
million tones of nutrients. ‘About 1/3 of this is lost
in sea while the rest in reservoirs and rivers leading
to flood.
About 38% of the area in India suffers from
moderate to high degree of water based erosion. All
these lands cannot be utilized for agricultural
purpose. Some land would be required for other
activities (to maintain urban area).

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Land Degradation:
 Land degradation is defined as the reduction in soil
capacity to produce in terms of quality, quantity
goods and services. The definition is also based on
 Sustainability or ability to produce continuously
and indefinitely.
 Quality of land resource that makes it sustainable
or resistant to degradation
 Carrying capacity or the number of people and
animals the land can normally support without
significant stress.
 Whenever degradation occur exceeding nature’s
restorative capacity, the result will be a disaster.

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Man induced landslides:
Land slides are the process of large differential
movement of two land portion. The hill slopes are prone
to land slides, landslips, rockslides etc.,. These hazardous
features have reduced the overall progress of the region as they
obstruct the roads, communication media and water flow.
There are two types of slides
 Slides due to natural factors
 Slides induced by man and his activities
Some of the human activities that cause land sliding are
1. Massive deforestation.
2. Erratic agricultural practices.
3. Road building.
4. Engineering Constructions.

60. Soil erosion
Soil erosion is the process of removal of superficial layer of
the soil from one place to another. Soil erosion also removes the
soil components and surface liter.
Types: i) Normal erosion – by natural processes
ii) Accelerated erosion – by manmade activities
Effects: a) Soil fertility is lost – due to loss of top soil layer.
b) Loss of its ability to hold water and sediment.
c) Sediment runoff – pollute water and kill aquatic life.
Causes: 1. Water: form of rain, runoff, rapid flow, wave action
2. Wind: carry away the fine particles of soil.
3. Biotic agents: overgrazing, mining
4.Construction: dams, buildings, roads.
5. Landslides : It also causes soil erosion.
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62. 62
Soil Conservation: Ways to reduce soil erosion
 Terracing: Terracing reduces soil erosion on steep slopes by
concerting the land into a series of broad, level terraces. This
retains water for crops at each level and reduces soil erosion
by water run off.

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Contour Farming: This method is adopted for gently sloped
land. This involves planting crops in rows across the contour of
gently sloped land.

64. Agro forestry: In this method crops are planted together in strips
or alleys between trees and shrubs that can provide fruits and fuel
wood. The trees and shrubs provide shade which reduce water
loss by evaporation and preserve soil moisture.
64

65. Wind Breaks : Wind breaks and shelter
belts or trees are established to reduce wind
erosion and also for retaining soil moisture
65

66. Desertification: Desertification is a progressive
destruction or degradation of arid or semiarid lands to
desert. Desertification leads to the conversion of croplands
to desert.
Causes of desertification:
 Deforestation
Over grazing
Water management
Mining and quarrying
Climate change
Pollution.
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67. Role of individual in conservation of natural resources
Resources are being exhaustible, it is the duty of every
individual on this earth to conserve the natural resources in
such a way that they must be available for future
generation also.
Measures recommended for conservation of natural
resource
I. Conservation of Energy:
 Switch off lights, fans and other appliances when not
in use.
 Use solar heater for cooking your food on sunny days,
which will cut down your LPG expenses.
 Dry the clothes in sunlight instead of driers.
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68.  Grow trees near the houses and get a cool breeze and
shade. This will cut off your electricity charges on A/C and
coolers.
 Use always pressure cooker.
 Ride bicycle or just walk instead of using car and scooter.
II. Conservation of water:
 Use minimum water for all domestic purposes.
 Check for water leaks in pipes and toilets and repair them
promptly.
 Reuse the soapy water, after washing clothes, for washing
off the courtyards, drive ways, etc.
 Use drip irigation to improve irrigation efficiency and
reduce evaporation.
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69.  The wasted water, coming out from kitchen, bath tub can
be used for watering the plants.
 Build rainwater harvesting system in your house.
III. Conservation of soil:
 Grow different types of plants, herbs, trees and grass in
your garden and open areas, which bind the soil and
prevent its erosion.
 Don’t uproot the trees as far as possible.
 Don’t irrigate the plants using a strong flow of water, as it
will wash off the top soil.
 Soil erosion can be prevented by the use of sprinkling
irrigation.
 Use green manure in the garden, which will protect the
soil.
 Use mixed cropping- specific nutrients not get depleted.
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70. IV. Conservation of Food Resources:
Eat only minimum amount of food. Avoid
over eating.
Don’ t waste the food instead give it to
someone.
Cook only required amount of the food.
Don’t cook food unnecessarily.
Don’t store large amounts of food grains and
protect them from damaging insects.
V. Conservation of Forest Resources:
Use non-timber products.
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71. Minimize the use of papers and fuel wood.
Avoid of executing developmental work like
dam, road, construction in forest areas.
Sustainable development
Sustainable development is the
development of healthy environment
without damaging the natural resources. In
other words, all the natural resources must
be used in such a way that it must be
available for the future generation also.
Unsustainable development
Unsustainable development is the 71

72. Life style in different countries:
1. Life style in most developed countries:
The most developed countries have only 22%
of world’s population, but they are using 88% of
its natural resources.
They contribute more nearly 85% of total
global income. They contribute more proportion
to its pollution.
As the rich countries are developing more,
they are consuming more natural resources and
polluting the environment more. The
sustainability of the earth’s life supporting72

73. 2. Life style in less developed countries:
The less developed countries have 78% of the
world’s
Population and are using only about 12% of its
natural resources. Their income is only 15%
of total global income. They have very low
industrial growth. They are still struggling hard
with their large population and poverty
problems. They are consuming too low natural
resources leading to unsustainability.

74. Causes of unsustainability:
The main cause is due to the difference between the less
developed and more developed countries. i.e.,
i) Over population in poor counties, consume too low
resources with low income.
ii) Rich countries consume more resources with more income.
Conditions for sustainable life style
1. It is essential to achieve a more balanced and equitable
distribution of land resources and income to meet
everyone’s basic needs.
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75. 2.The rich countries should lower down their consumption
levels, while the minimum needs of the poor should be
fulfilled by providing them resources.
Thus more balanced and equitable use of resources
will reduce the differences between the most developed
countries and less developed countries and will lead to
sustainable.
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76. 76

77. 77

78. 78
HYDROLOGICAL CYCLE

79. 79

80. 80

81. 81