Natural Resources: Renewable and Non-Renewable Resources

Natural resources (प्राकृतिक संसाधन)

Non-renewable resources (अनवीकरणीय संसाधन)
Renewable resources (नवीकरणीय संसाधन)
Land resources and land use change: Land as a resource, land
degradation, landslides (natural & man-induced), soil erosion and
desertification.

Forests & forest resources: Use and over-exploitation, deforestation,

case studies.
Impacts of deforestation, mining, dam building on environment, forests,
biodiversity and tribal populations.
Resettlement (पुनर्वास) and rehabilitation of project affected persons;
problems and concerns, case studies

Water resources: Use and over-exploitation of surface and ground

water, floods, drought, conflicts over water (international & inter-state).

Food resources: World food problems, changes caused by agriculture

and overgrazing, effects of modern agriculture, fertilizer-pesticide
problems, water logging, salinity, case studies.
Energy resources: Renewable and non-renewable energy sources, use
of alternate energy sources, growing energy needs, case studies.

Natural Resources
A natural resource may be defined as any material given to us by
transformed in a way that it becomes more valuable and useful.
These natural resources include, air, water, soil, minerals, along with the
climate and solar energy, which form the non-living or ‘abiotic’ part of
nature.
The ‘biotic’ or living parts of nature consists of plants and animals, including
microbes. Plants and animals can only survive as communities of different
organisms, all closely linked to each in their own habitat, and requiring
specific abiotic conditions.

Renewable Resources
Renewable resources are the ones that are consistently available regardless
of their use. They can be fairly recovered or replaced after utilisation.
• • It can be renewed as it is available in infinite quantity
• • Sustainable in nature
• • Low cost and environment-friendly
• • Replenish quickly

Non-renewable Resources
Resources, if they are used in unlimited way, they cannot be easily replaced.
Thus, their exploitation at large scale will result in their fast depletion. Some
such resources are called non-renewable resources or exhaustible. Example
iron ore, coal, mineral oil etc.
• • Once completely consumed, it cannot be renewed due to limited
stock
• • Exhaustible in nature
• • High cost and less environment-friendly
• • Replenish slowly or do not replenish naturally at all

TYPES OF NATURAL RESOURCES

1. Land Resources
2. Forest Resources
3. Water Resources
4. Energy Resources
5. Food resources

LAND RESOURCES
(a) Land as a resource: Landforms such as hills, valleys, plains, river
basins and wetlands include different resource generating areas that the
people living in them depend on.
If land is utilized carefully, it can be considered a renewable resource. The
roots of trees and grasses bind the soil. If forests are depleted, or grasslands
overgrazed, the land becomes unproductive and wasteland is formed.
Intensive irrigation leads to water logging and salination, on which crops
cannot grow. Land is also converted into a non-renewable resource when
highly toxic industrial and nuclear wastes are dumped on it. Land is also
converted into a non-renewable resource when highly toxic industrial and
nuclear wastes are dumped on it.
(b) Land use change: The most damaging change in land use is
demonstrated by the rapidity with which forests have vanished during recent
times, both in India and in the rest of the world. Forests provide us with a
variety of services.
(c) Land degradation: It is a process of deterioration of soil or loss of
fertility. Due to increasing population, the demands for arable land for
producing food, fibre and fuel wood is also increasing. Hence there is more
and more pressure on the limited land resources which are getting degraded
due to over-exploitation. Nearly 56% of total geographical area of the
country is suffering due to land resource degradation. Out of 17-million-
hectare canal irrigated area, 3.4 million hectares is suffering from water
logging and salinity.
Effects of land degradation:
1. Soil texture and soil structure are destructed.
2. Loss of soil fertility.
3. Loss of valuable nutrients.
4. increase in water logging, salinity, alkalinity and acidity problem.
5. Loss of economic social and biodiversity.
Causes of land degradation:
1. Population: More land is needed for producing food, fibre and fuel wood.
So, land is degraded due to over exploitation.
2. Urbanisation: Urbanisation reduces the agricultural land. Urbanisation
leads to deforestation, which in turn affects millions of plants and animals.
3. Fertilizers and pesticides: It affects fertility of the soil and causes land
pollution.
4. Damage of top soil: Increase in food production generally leads to
damage of top soil through nutrient depletion.
5. Water logging, soil erosion, salination and contamination of the soil
with industrial wastes and cause land degradation.

(d) Soil erosion: The process of loss or removal of superficial layer of soil
due to the action of wind, water and human factors. In other words, it can be
defined as the movement of soil components, especially surface-litter and
top soil from one place to another. It has been estimated that more than
5000 million tonnes topsoil is being eroded annually and 30% of total eroded
mass is getting loosed to the sea.
Types of soil erosion:
1. Geological erosion: It is caused by gradual removal of top soil by the
natural process. The rate of erosion is less.
2. Accelerated erosion: It is caused by man-made activities. The erosion is
much faster than the rate formation of soil.
Causes of soil erosion:
1.water: water causes soil erosion in the form of rain, run off, rapid flow and
wave action.
2.wind: It is an important climatic agent, which carry away the fine particles
of soil creates soil erosion.
3.Biotic agent: Over grazing, mining and deforestation are the major biotic
agent cause soil erosion. 35% of soil erosion is due to over grazing and 30%
is due to deforestation.
4. Land slide: It causes soil erosion.
5. Construction: Construction of dams, buildings, roads remove protective
vegetal cover and leads to soil erosion.
Control of soil erosion (or) Soil conservation practices: The art of soil
conservation is based on following basic principles
1. To slow down the water for concentrating and moving down the slope in a
narrow path.
2. To slow down the water movement when it flows along the slope.
3. To encourage more water to enter into the soil.
4. To increase the size of soil particles.
5. Reduction in the wind velocity near the ground by growing vegetation.
Conservational tillage: The process of mixing the residues from previous
crops into the soil by ploughing is called conservational tillage. It improves
soil permeability and increase organic matter, which in turn improve soil
moisture and nutrients. Organic farming: Process of increasing organic input
to the soil. E.g., bio fertilizer Crop rotation: Process of growing different crops
in successive year on the same land. It prevents the loss of fertility of the
soil.
Contour Ploughing: It is very useful areas with low rain fall, i.e., placing
some furrows to
store water, which reduces runoff and erosion.
Mulching: Soil is covered with crop residues and other form of plant litters.
Strip cropping: Planting of crops in rows to check flow of water.
Terrace farming: Conversion of steep slopes in to a series of broad terraces
which run across
the contour. It reduces soil erosion by controlling run off.
Agroforestry: Planting crops in between rows of trees or shrubs, that can
provide fruits and
fuel wood. After harvesting the crops, the soil will not be eroded because
trees and shrubs will
remain on the soil and hold the soil particles.
Wind break: Trees are planted in long rows along the boundary of cultivated
lands, which
block the wind and reduces soil erosion.

(e) Desertification: Desertification is a process whereby the productive

potential of arid or semiarid lands falls by ten percent or more.
Desertification is characterised by de-vegetation and depletion of
groundwater, salinization and severe soil erosion.
Causes: 1. Deforestation
2. Over grazing
3. Over utilisation of water
4. Mining and quarrying
5. Climate change
6. Excessive use of fertilizers and pesticides

Effects of desertification: 80% of productive land in the arid and semi-arid

regions are converted in to desert. Around 600million people are suffered by
desertification.

FORESTS & FOREST RESOURCES

Forest is important renewable resources. Forest varies in composition and
diversity and can contribute substantially to the economic development of
any country. Plants along with trees cover large areas, produce variety of
products and provide food for living organisms, and also important to save
the environment.
It is estimated that about 30% of world area is covered by forest whereas
26% by pastures. Among all continents, Africa has largest forested area
(33%) followed by Latin America (25%), whereas in North America forest
cover is only 11%. Asia and former USSR has 14% area under forest.
European countries have only 3% area under forest cover. India’s Forest
Cover accounts for 20.6% of the total geographical area of the country as of
2005.
Functions of Forest Resources
1. Ecological Balance
2. Renewable Natural Resources
3. Eco-system
4. Economic Development
5. Environment Quality
6. Safeguard against Pollution
7. Soil Conservation
8. Wind Erosion
9. Check the Extension Balance
10. Maintains Ecological Balance
11. Attract Rainfall
12. Control Floods
13. Linked with Cultural and Civilization
14. Supply of Raw Material

Significance of forests
Forest can provide prosperity of human being and to the nations. Important
uses of forest can be classified as under
i. (i) Commercial values
• Forests are main source of many commercial products such as wood,
timber, pulpwood etc. About 1.5 billion people depend upon fuel wood as an
energy source. Timber obtained from the forest can used to make plywood,
board, doors and windows, furniture, and agriculture implements and sports
goods. Timber is also a raw material for preparation of paper, rayon and film.
• Forest can provide food, fibre, edible oils and drugs.
• Forest lands are also used for agriculture and grazing.
• Forest is important source of development of dams, recreation and mining.
 i. (ii) Life and economy of tribal Forest provide food, medicine and
other products needed for tribal people and play a vital role in the
life and economy of tribes living in the forest.
ii. (iii) Ecological uses Forests are habitat to all wild animals,
plants and support millions of species. They help in reducing global
warming caused by greenhouse gases and produces oxygen upon
photosynthesis. Forest can act as pollution purifier by absorbing
toxic gases. Forest not only helps in soil conservation but also helps
to regulate the hydrological cycle.
iii. (iv) Aesthetic values All over the world people appreciate the
beauty and tranquillity of the forest because forests have a greatest
aesthetic value. Forest provides opportunity for recreation and
ecosystem research.
2. Over exploitation of forests
Forests contribute substantially to the national economy. With increasing
population increased demand of fuel wood, expansion of area under urban
development and industries has led to over exploitation of forest. At present
international level we are losing forest at the rate of 1.7 crore hectares
annually. Overexploitation also occurs due to overgrazing and conversion of
forest to pastures for domestic use.
3. Deforestation
Forests are burned or cut for clearing of land for agriculture, harvesting for
wood and timber, development and expansion of cities. These economic
gains are short term whereas long-term effects of deforestation are
irreversible.
1. Deforestation rate is relatively low in temperate countries than in tropics If
present rate of deforestation continues, we may losses 90% tropical forest in
coming six decades
2. For ecological balance 33% area should be under forest cover but our
nation has only 20.6% forest cover. Causes of deforestation Forest area in
some developed area has expanded. However, in developing countries area
under forest is showing declining trend particularly in tropical region. Main
causes of deforestation are
a) Shifting cultivation or jhum cultivation This practise is prevalent in
tribal areas where forest lands are cleared to grow subsistence crops. It is
estimated that the principle cause of deforestation in tropics in Africa, Asia
and tropical America is estimated to be 70, 50, and 35% respectively.
Shifting cultivation which is a practice of slash and burn agriculture are
posses to clear more than 5 lakh hectares of land annually. In India, shifting
cultivation is prevalent in northeast and to limited extent in M.P, Bihar and
Andhra Pradesh and is contributing significantly to deforestation.
b) Commercial logging It is a important deforestation agent. It may not be
the primary cause but definitely it acts as secondary cause, because new
logging lots permits shifting cultivation and fuel wood gatherers access to
new logged areas.
c) Need for fuel wood Increased population has led to increasing demand
for fuel wood which is also acting as an important deforestation agent,
particularly in dry forest.
d) Expansion for agribusiness with the addition of cash crops such as oil
palm, rubber, fruits and ornamental plants, there is stress to expand the area
for agribusiness products which results in deforestation.
e) Development projects and growing need for food The growing
demand for electricity, irrigation, construction, mining, etc. has lead to
destruction of forest. Increased population needs more food which has
compelled for increasing area under agriculture crops compelling for
deforestation.
f) Raw materials for industrial use Forests provides raw material for
industry and it has exerted tremendous pressure on forest. Increasing
demand for plywood for backing has exerted pressure on cutting off other
species such as fir to be used as backing material for apple in J&K and tea in
northeast states.
Major effects of deforestation
Deforestation adversely and directly affects and damages the environment
and living beings.
Major causes of deforestation are
• Soil erosion and loss of soil fertility
• Decrease of rain fall due to effect of hydrological cycle
• Expansion of deserts
• Climate change and depletion of water table
• Loss of biodiversity, flora and fauna
• Environmental changes and disturbance in forest ecosystems
4.Case studies

WATER RESOURCES
Water is an indispensable resource for life on earth. Approximately 70.8 %
surface of earth is covered with water in the form of oceans. Out of this,
about 97% is not fit for human consumption, about 2% is locked as a glacier
and only less than 1% available as fresh water that can be used for human
consumption and other uses.
Water is a very important source and essential for life because it has very
unique characteristic such as 1. Water exists as liquid over a wide range of
temperature 0-1000C with highest specific heat and latent heat of
vaporization.
2. Water is excellent solvent and act as carrier of nutrient and helps to
distribute them to the cells in the body, regulates the body temperature and
support structure and can dissolve various pollutant and can act as carrier of
large number of microorganisms
3. It is responsible for hydrological cycle which acts as resource of water to
the earth. It is estimated that about 1.4-inch-thick layer of water evaporates
and majority of water returns to earth through hydrological cycle. Water is
renewable, but its overuse and pollution make it unfit for use.
Sewage, industrial use, chemicals, etc. pollute water with nitrates, metals,
and pesticides.
Use of Water Resources
Water resources are used for agricultural, industrial, domestic, recreational,
and environmental activities. Majority of the uses require fresh water.
However, about 97 percent of water found on the earth is salt water and only
three percent is fresh water. A little over two-thirds of the available fresh
water is frozen in glaciers and polar ice caps. The remaining freshwater is
found mainly as groundwater and a negligible portion of it is present on the
ground or in the air
Following is a brief account of how water is used in different sectors.
i. (i) Agricultural Use: Agriculture accounts for 69 percent of all
water consumption basically in agricultural economies like India.
Agriculture, therefore, is the largest consumer of the Earth’s
available freshwater. By 2050, the global water demand of
agriculture is estimated to increase by a further 19% due to
irrigational needs. Expanding irrigation needs are likely to put undue
pressure on water storage. It is still inconclusive whether further
expansion of irrigation, as well as additional water withdrawals from
rivers and groundwater, will be possible in future.
ii. (ii) Industrial Use: Water is the lifeblood of the industry. It is
used as a raw material coolant, a solvent, a transport agent, and as
a source of energy. Manufacturing industries account for a
considerable share in the total industrial water consumption.
Besides, paper and allied products, chemicals and primary metals
are major industrial users of water. Worldwide, the industry
accounts for 19 percent of total consumption. In industrialised
countries, however, industries use more than half of the water
available for human use.
iii. (iii) Domestic Use: It includes drinking, cleaning, personal
hygiene, garden care, cooking, washing of clothes, dishes, vehicles,
etc. Since the end of World War II there has been a trend of people
moving out of the countryside to the ever-expanding cities. This
 trend has important implications on our water resources.
Government and communities have had to start building large
water-supply systems to deliver water to new populations and
industries. Of all water consumption in the world, domestic use
accounts for about 12 percent. (iv)Use for
iv. (iv) Hydropower Generation: Electricity produced from
water is hydropower. Hydropower is the leading renewable source of
electricity in the world. It accounts for about 16 percent of total
electricity generation globally. There are many opportunities for
hydropower development throughout the world. Today, the leading
hydropower generating countries are China, the US, Brazil, Canada,
India, and Russia.
v. (v) Use for Navigation and Recreation: Navigable
waterways are defined as watercourses that have been or may be
used for transport of interstate or foreign commerce. Agricultural
and commercial goods are moved on water on a large scale in a
number of regions in the world. Water is also used for recreational
purposes such as boating, swimming, and sporting activities. These
uses affect the quality of water and pollute it. Highest priority
should be given to public health and drinking water quality while
permitting such activities in reservoirs, lakes, and rivers.
Over-Exploitation of Water Water scarcity has become a burning global
issue. The UN has held several conventions on water in recent decades.
Continuous over utilisation of surface and ground water has led to virtual
water scarcity in the world today. The depleting sources for high growth in
human population over the centuries and increased man-induced water
pollution across the world have created unforeseen water scarcity around
the globe. As a result, there has been continuous over utilisation of the
existing water sources due to mammoth growth in world population.
Surface water Surface water mainly comes directly from rain or snow
covers. The various surface sources are natural lakes and ponds, rivers
and streams, artificial reservoirs. Availability of surface water decides the
economy of the country. On one side surface water availability affects the
productivity, but on the other side water sources may cause floods and
drought. Due to unequal distribution, water may lead to national
(interstate) or international disputes. Sharing of surface water due to
these disputes is affecting productivity of different agro eco-zone and
creating problems for government.
Ground water Groundwater is the major source of water in many parts of
the world. However, there has been continuous depletion of this source
due to its overexploitation by rising human population and the rapid rise
in industrialisation and urbanisation in modern times. About 9.86% of the
total fresh water resources are in the form of groundwater and it is about
35-50 times that of surface water supplies.
Effects of extensive and reckless groundwater usage: 1. Subsidence 2.
Lowering of water table 3. Water logging
Consequences of Over utilization Water scarcity now becomes an
important topic in international diplomacy. From village to the United
Nations, water scarcity is a widely-discussed topic in decision making.
Nearly three billion people in the world suffer from water scarcity.
International, intrastate and regional rivalries on water are not new to
world. The ongoing Jordan River conflict, Nile River conflict, and Aral Sea
conflict are cases in point. The intra-state issues such as Cauvery Water
dispute in South India, 2000 Cochabamba protests in Bolivia is still a
simmering cauldron causing periodic tension at the national and regional
levels.
According to World Health Organisation (WHO) sources, a
combination of rising global population, economic growth and climate
change means that by 2050 five billion (52%) of the world’s projected 9.7
billion people will live in areas where fresh water supply is under pressure.
Researchers expect about 1 billion more people to be living in areas
where water demand exceeds surface-water supply.
(i)Climate Change Scientists, environmentalists, and biologists
worldwide are now alarmed that climate change can have an impact on
the drainage pattern and hydrological cycle on the earth thereby severely
affecting the surface and groundwater availability. Climate change is
believed to rise the global temperature at an increasing pace.
Temperature increase affects the hydrological cycle by directly increasing
evaporation of available surface water and vegetation transpiration. As a
result, precipitation amount, timing and intensity rates are largely
affected. It impacts the flux and storage of water in surface and
subsurface reservoirs.
(ii)Floods & Draughts Floods and droughts are two well-known
natural hazards in the world. The former is due to excess in water flow
and the latter is due to scarcity of water. The amount of rainfall received
by an area varies from one place to another depending on the location of
the place. In some places it rains almost throughout the year whereas in
other places it might rain for only few days. India records most of its
rainfall in the monsoon season.
Heavy rains lead to rise in the water level of rivers, seas, and oceans.
Water gets accumulated in the coastal areas, which results in floods.
Floods bring in extensive damage to crops, domestic animals, property
and human life. During floods, many animals get carried away by the
force of water and eventually die.
On the other hand, droughts set in when a particular region goes without
rain for a long period of time. In the meantime, the soil will continuously
lose groundwater by the process of evaporation and transpiration. Since
this water is not brought back to earth in the form of rains, the soil
becomes very dry.
The level of water in the ponds and rivers goes down and in some cases
water bodies get dried up completely. Ground water becomes scarce and
this leads to droughts. In drought conditions, it is very difficult to get food
and fodder for the survival. Life gets difficult and many animals perish in
such conditions.
Frequent floods and droughts are mostly due to climate change and global
warming. Various environmental organizations world over are of the view
that climate change is a long-term change in weather patterns, either in
average weather conditions or in the distribution of extreme weather
events.
Major Water Conflicts Some of the major water conflicts that have become
thorn in relations between states and countries are
(1) Water conflict in the middle east Countries involved are Sudan,
Egypt and Turkey. It also affects countries which are water starved viz.
Saudi Arabia, Kuwait, Syria, Israel and Jordan.
(2) The Indus water treaty This Indus water treaty dispute between
India and Pakistan is lingering since long.
(3) The Cauvery water dispute It involves two major states of India viz.
Tamil Nādu and Karnataka.
(4) The Satluj-Yamuna link canal dispute The dispute is between two
Northern states viz. Punjab and Haryana and UP, Rajasthan as well as
Delhi has also interest in it. In traditional water management, innovative
arrangements ensure equitable distribution of water, which are
democratically implemented. These disputes can be solved amicably
through ‘Gram Panchayats”, if transparency is maintained. But disputes
between countries or states sometimes attain war like situation and are
difficult to solve.
Dams - Benefits and Problems
Water is a precious resource and its scarcity is increasing at global level.
There is a pressure to utilise surface water resources efficiently for
different purposes. Dam, structure built across a stream, a river, or an
estuary to retain water. Dams are built to provide water for human
consumption, for irrigating arid and semiarid lands, or for use in industrial
processes.
Major benefits of dams
The major benefits of dams are
1. Hydroelectricity generation
2. Year-round water supply to ensure higher productivity
3. Equal water distribution by transferring water from area of excess to
area of deficit 4. Helps flood control and protects soil
5. Assure irrigation during dry periods
6. River valley projects provide inland water navigation, employment
opportunities and can be used to develop fish hatcheries and nurseries
7. River valley projects have tremendous potential for economic
upliftment and will help to raise the standard of living and can help to
improve the quality-of-life Disadvantages/problems Although dams have
proved very useful over the centuries but recent past big dams have
created lot of humans as well as environmental issues
1. Submergence of large areas may lead to loss of fertile soil and
displacement of tribal people
2. Salt left behind due to evaporation increase the salinity of river water
and makes it unusable when reaches down stream
3. Siltation and sedimentation of reservoirs not only makes dams use less
but also is responsible for loss of valuable nutrients
4. Loss of non-forest land leads to loss of flora and fauna
5. Changes in fisheries and the spawning grounds
6. Stagnation and water logging near reservoir leads to breeding of
vectors and spread of vector-borne diseases
7. Growth of aquatic weeds may lead to microclimatic changes.

(IV) ENERGY RESOURCES

Energy Scenario Energy is a key input in economic growth and there is a
close link between the availability of energy and the future growth of a
nation. Power generation and energy consumption are crucial to economic
development.
In India, energy is consumed in a variety of forms such as fuel wood;
animal waste and agricultural residues are the traditional sources of
energy. These non-commercial fuels are gradually getting replaced by
commercial fuels i.e. coal, petroleum products, natural gas, and electricity.
Out of total energy, commercial fuels account for 60% whereas the
balance 40% is coming from non-commercial fuels.
Of the total commercial energy produced in the form of power or
electricity,
69% is from coal (thermal power),
25% is from hydal power,
4% is from diesel and gas,
2% is from nuclear power, and less than 1% from non-conventional
sources like solar, wind, ocean, biomass, etc.
Petroleum and its products are the other large sources of energy. In a
developing country like India, in spite of enhanced energy production,
there is still a shortage due to increased demand for energy. In spite of
the fact that there is a phenomenal increase in power generating
capacity, still there is a 30% deficit of about 2,000 million units.
Policymakers are in the process of formulating an energy policy with the
objectives of ensuring adequate energy supply at a minimum cost,
achieving self-sufficiency in energy supplies, and protecting the
environment from the adverse impact of utilising energy resources in an
injudicious manner. The main features of this policy are
• Accelerated exploitation of domestic conventional energy resources,
viz., oil, coal, hydro and nuclear power;
• Intensification of exploration to achieve indigenous production of oil and
gas;
• Efficient management of demand for oil and other forms of energy;
• To formulate efficient methods of energy conservation and
management;
• Optimisation of utilisation of existing capacity in the country
 • Development and exploitation of renewable sources of energy to meet
energy requirements of rural communities;
• Organisation of training for personnel engaged at various levels in the
energy sector.
• Government private partnership to exploit natural energy resources
Renewable Resources The resources that can be replenished through
rapid natural cycles are known as a renewable resources. These resources
are able to increase their abundance through reproduction and utilisation
of simple substances.
Non-Renewable Resources
The resources that cannot be replenished through natural processes are
known as non-renewable resources. These are available in limited
amounts, which cannot be increased.
These resources include fossil fuels (petrol, coal etc.), and nuclear energy
sources (e.g., uranium, thorium, etc). metals (iron, copper, gold, silver,
lead, zinc etc.), minerals and salts (carbonates, phosphates, nitrates etc.).
Once a non-renewable resource is consumed, it is gone forever. Then we
have to find a substitute for it or do without it. Non-renewable resources
can further be divided into two categories, viz. Recyclable and non-
recyclable.
Recyclable resources
These are non-renewable resources, which can be collected after they are
used and can be recycled. These are mainly the non-energy mineral
resources, which occur in the earth’s crust (e.g., ores of aluminium, copper,
mercury etc.) and deposits of fertilizer nutrients (e.g. phosphate sock and
potassium and minerals used in their natural state (asbestos, clay, mica etc.)
Non-recyclable resources
These are non-renewable resources, which cannot be recycled in any way.
Examples of these are fossil fuels and nuclear energy sources (e.g., uranium,
etc) which provide 90 percent of our energy requirements.
Use of Alternate Energy Sources
There is a need to develop renewable energy sources which are available
and could be utilised (solar or wind) or the sources which could be created
and utilised (bio-mass). The main renewable energy sources for India are
solar, wind, hydal, waste, and bio-mass. Biomass is resources that are
agriculture-related like wood, bagasse, cow dung, seeds, etc.
(1) Hydal energy India has a total hydro energy potential of about 1.5 lakh
MW, of which only about 20 % is installed. Small hydro plant potential is
about 15000 MW and most of it is in the northern and eastern hilly regions.
(2) Wind energy The wind power potential of India is about 45,000 MW out
of which a capacity of 8748 MW has been installed in India till 2008. India is
one of the leading countries in generating power through wind energy.
Gujarat, AP, Karnataka, MP and Rajasthan are states having more than 5000
MW potential each. These potentials could be improved if the technology of
putting turbines in the sea is embraced. There are wind farms on sea
generating as high as 160 MW of power.
(3) Geothermal energy is thermal energy generated and stored in the
Earth. Thermal energy is the energy that determines the temperature of
matter. Earth's geothermal energy originates from the original formation of
the planet (20%) and from the radioactive decay of minerals (80%).
Geothermal power is cost-effective, reliable, sustainable, and
environmentally friendly, but has historically been limited to areas near
tectonic plate boundaries. Recent technological advances have dramatically
expanded the range and size of viable resources, especially for applications
such as home heating, opening a potential for widespread exploitation.
Geothermal wells release greenhouse gases trapped deep within the earth,
but these emissions are much lower per energy unit than those of fossil
fuels. As a result, geothermal power has the potential to help mitigate global
warming if widely deployed in place of fossil fuels.
(4) Ocean thermal energy conversion (OTEC) Ocean Thermal Energy
Conversion (OTEC) uses the difference between cooler deep and warmer
shallow or surface ocean waters to run a heat engine and produce useful
work, usually in the form of electricity. A heat engine gives greater efficiency
and power when run with a large temperature difference. In the oceans, the
temperature difference between surface and deep water is greatest in the
tropics, although still a modest 20 to 25 °C. It is therefore in the tropics that
OTEC offers the greatest possibilities. OTEC has the potential to offer global
amounts of energy that are 10 to 100 times greater than other ocean energy
options such as wave power
(5) Biomass energy Biomass is the oldest means of energy used by
humans along with solar energy. As soon as the fire was discovered, it was
used widely among humans mainly for heat and light. The fire was generated
using wood or leaves, which is basically biomass. The biomass could be used
to generate steam or power or used as a fuel. Power is generated using rice
husk in Andhra Pradesh, while several bagasse-based plants are there. India
has a potential of 3500 MW from bagasse. Other fast-growing plants could be
planned over a huge area so that it provides biomass for generating power.
Organic waste such as dead plant and animal material, animal dung, and
kitchen waste can be converted by the anaerobic digestion or fermentation
into a gaseous fuel called biogas. Biogas is a mixture of 65% methane (CH 4)
and of 35% CO2 and may have small amounts of hydrogen sulphide (H 2S),
moisture, and siloxanes. It is renewable energy resulting from biomass.
Biogas can be used as a fuel in any country for any heating purpose, such as
cooking. It can also be used in anaerobic digesters where it is typically used
in a gas engine to convert the energy in the gas into electricity and heat.
Biogas can be compressed, much like natural gas, and used to power motor
vehicles.
(6) Bio-fuels India has more than 50 million hectares of wasteland, which
could be utilized for cultivating fuel plants. Jatropha is one of the options
which can be planted on arid lands and be used for the production of
biofuels.
(7) Solar energy India being a tropical country has the potential to use
solar energy on commercial bases. According to estimates, 35 MW of power
could be generated from 1 sq. km. With such potential, solar energy has a
bright future as the energy source for the development of the country. The
initial cost is the biggest limitation which has led to the low realization of its
potential.
For solar energy to become one of the front runners, it will require a lot of
research, cheap technology, and low capital.
Problems Relate to the Use of Energy Resources
(1) Fossil fuel
• Global warming
• Acid rains
• Dangers posed by leaded fuels, Oil spills
• Water pollution caused by poorly managed coal mines
• Air pollution.
(2) Alternate energy resources
• The initial cost of establishment of alternate energy generation is costlier
than conventional resources.
• Maintenance of these structures is difficult.
• It requires more space.
• Energy supply is unpredictable during natural calamities.
Growing Energy Needs
The energy consumption of a nation is usually considered an index of its
development because almost all the development activities are directly or
indirectly dependent upon energy. Power generation and energy
consumption are crucial to economic development as the economy of any
nation depends upon the availability of energy resources. There are wide
disparities in per capita energy use of developed and developing nations.
With the increased speed of development in the developing nations energy
needs are also increasing.
• The very original form of energy technology probably was the fire, which
produced heat and the early man used it for cooking and heating purposes.
• Wind and hydropower have also been used. The invention of steam
engineers replaced the burning of wood with coal and coal was further
replaced by oil.
• The oil production has started twisting the arms of the developed as well as
developing countries by dictating the prices of oil and other petroleum
products.
• Energy resources are primarily divided into two categories viz. renewable
and non-renewable sources.
• Renewable energy resources must be preferred over non-renewable
resources.
• It is an inevitable truth that now there is an urgent need of thinking in
terms of alternative sources of energy, which are also termed non-
conventional energy sources which include:
✓ Solar energy needs equipments such as solar heat collectors, solar cells,
solar cookers, solar water heaters, solar furnaces, and solar power plants.
✓ Wind energy ✓ Hydropower, Tidal energy, ocean thermal energy,
geothermal energy, biomass, biogas, biofuels, etc.
• The non-renewable energy sources include coal, petroleum, natural gas,
and nuclear energy.
Case Study
FOOD RESOURCES
Food is essential for the growth and development of living organisms. These
essential materials are called nutrients and these nutrients are available
from a variety of animals and plants. There are thousands of edible plants
and animals over the world, out of which only about three dozen types
constitute the major food for humans.
Food sources
The majority of people obtain food from cultivated plants and domesticated
animals. Although some food is obtained from oceans and fresh waters, the
great majority of food for the human population is obtained from traditional
land-based agriculture of crops and livestock.
Food crops
It is estimated that out of about 2,50,000 species of plants, only about 3,000
have been tried as agricultural crops. Under the different agro-climatic
conditions, 300 are grown for food and only 100 are used on a large scale.
Some species of crops provide food, whereas others provide commercial
products like oils, fibers, etc. Raw crops are sometimes converted into
valuable edible products by using different techniques for value addition. At
the global level, only 20 species of crops are used for food. These, in
approximate order of importance, are wheat, rice, corn, potatoes; barley,
sweet potatoes, cassavas, soybeans, oats, sorghum, millet, sugarcane, sugar
beets, rye, peanuts, field beans, chick-peas, pigeon- peas, bananas and
coconuts. Many of them are used directly, whereas others can be used by
changing them by using different techniques for enhancing calorific value.
Livestock
Domesticated animals are an important food source. The major domesticated
animals used as food sources by human beings are ‘ruminants’ (e.g. cattle,
sheep, goats, camel, reindeer, llama, etc.).
Ruminants convert indigestible woody tissue of plants (cellulose) which are
earth’s most abundant organic compounds into digestible food products for
human consumption. Milk, which is provided by milking animals, is
considered to be the complete food. Other domestic animals like sheep,
goats, poultry and ducker can be used as meat.

Aquaculture
Fish and seafood contribute 17 million metric tonnes of high-quality protein
to provide a balanced diet to the world. Presently aquaculture provides only
small amounts of world food but its significance is increasing day by day.

World Food Problems

As per estimates by Food and Agriculture Organization (FAO), about 840
million people remain chronically hungry and out of this 800 million are living
in the developing world. In the last decade, it is decreasing at the rate of 2.5
million per year, but at the same time world’s population is increasing. The
target of cutting half the number of world’s chronically hungry and
undernourished people by 2015 will be difficult to meet, if the present trend
continues. Due to inadequate purchasing power to buy food, it is difficult to
fulfill the minimum calorific requirement of the human body per day. A large
number of people in India are poor which can be attributed to the equitable
distribution of income. Food insufficiency can be divided into two categories
into under-nourishment and malnourishment. Both of these insufficiencies
are global problems.
Under-nourishment
The FAO estimates that the average minimum daily caloric intake over the
whole world is about 2,500 calories per day. People who receive less than
90% of their minimum dietary intake on a long-term basis are considered
undernourished. Those who receive less than 80% of their minimum daily
caloric intake requirements are considered ‘seriously’ undernourished.
Children in this category are likely to suffer from stunted growth, mental
retardation, and other social and developmental disorders. Therefore, Under-
nourishment means a lack of sufficient calories in available food, resulting in
little or no ability to move or work.
Malnourishment
A person may have excess food but still, diet suffers from it due to nutritional
imbalance or inability to absorb or may have a problem to utilize essential
nutrients. If we compare the diet of the developed countries with developing
countries people in developed countries have processed food which may be
deficient in fibre, vitamins and other components whereas in the diet of
developing countries, maybe lack of specific nutrients because they
consume less meat, fruits and vegetables due to poor purchasing power.
Malnourishment can be defined as a lack of specific components of food such
as proteins, vitamins, or essential chemical elements.

The major problems of malnutrition are:

Marasmus: progressive emaciation caused by lack of protein and calories.
Kwashiarkor: a lack of sufficient protein in the diet which leads to a failure of
neural development and therefore learning disabilities.
Anemia: it is caused by lack of iron in the diet or an inability to absorb iron
from food.
Pellagra: it occurs due to the deficiency of tryptophan and lysine, vitamins in
the diet.
Every year, food problems kill as many people as were killed by the atomic
bomb dropped on Hiroshima during World War II. This shows that there is a
drastic need to increase food production, equitably distribute it, and also to
control population growth. Although India is the third-largest producer of
staple crops, it is estimated that about 300 million Indians are still
undernourished. India has only half as much land as the USA, but it has
nearly three times the population to feed. Our food problems are directly
related to the population.
Balanced diet
The supply of adequate amounts of a different nutrient can help to improve
malnutrition and its ill effects. Cereals like wheat and rice can supply only
carbohydrates which are rich in energy supply, and are only a fraction of the
nutrition requirement. A cereal diet has to be supplemented with other food
that can supply fat, protein and a minor quantity of minerals and vitamins. A
balanced diet will help to improve growth and health.
Changes Caused by Agriculture and Overgrazing
From centuries, agriculture is providing inputs to a large number of industries
involved in the production, processing and distribution of food. Accordingly,
agriculture has a significant effect on the environment. The effects of
agriculture on the environment can be classified as local, regional, and global
levels. Agriculture also makes an impact on the usage of land generally as
follows:
Deforestation
Soil Erosion
Depletion of nutrients
Impact related to high yielding varieties (HYV)
Fertilizers related problems include micronutrient imbalance, nitrite pollution
and eutrophication.
Pesticide-related problems include creating resistance in pests and producing
new pests, death of non-target organisms, and biological magnification.
Some other problems include water logging, salinity problems and such
others.
The carrying capacity of the land for cattle depends upon the micro climate
and soil fertility. If carrying capacity is exceeded then land is overgrazed.
Because of overgrazing, the agricultural land gets affected as follows,
Reduction in growth and diversity of plant species
Reduce plant cover leads to increased soil erosion
Cattle trampling leads to land degradation
Effects of Modern Agriculture
For sustainable production, modern techniques are used to enhance the
productivity of different cropping systems under different agro-eco-zones.
Adoption of modern agricultural practices has both positive and negative
effects on the environment. Effects of modern agriculture are briefly
discussed under different heads:
Soil erosion
Raindrops bombarding bare soil result in the oldest and still most serious
problem of agriculture. The long history of soil erosion and its impact on
civilization is one of devastation. Eroded fields record our failure as land
stewards.
Irrigation
Adequate rainfall is never guaranteed for the dry land farmer in arid and
semiarid regions, and thus irrigation is essential for reliable production.
Irrigation ensures sufficient water when needed and also allows farmers to
expand their acreage of suitable cropland. In fact, we rely heavily on crops
from irrigated lands, with fully one-third of the world's harvest coming from
that 17% of cropland that is under irrigation. Unfortunately, current irrigation
practices severely damage the cropland and the aquatic systems from which
the water is withdrawn.
Agriculture and the loss of genetic diversity
As modern agriculture converts an ever-increasing portion of the earth's land
surface to monoculture, the genetic and ecological diversity of the planet
erodes. Both the conversion of diverse natural ecosystems to new
agricultural lands and the narrowing of the genetic diversity of crops
contribute to this erosion.
Fertiliser- pesticide problems
For photosynthesis apart from water, sunshine, and CO 2, plants need micro
and macro nutrients for growth. These nutrients are supplied in the shape of
fertilizers. There is a lot of potentials to increase food productivity by
increasing fertilizer use. On one hand application of artificial chemical
fertilizers increases productivity at a faster rate as compared to organic
fertilizers, on the other hand, application of fertilizers can be a serious
problem of pollution and can create a number of problems. Excessive level of
nitrates in groundwater has created problems in developed countries. These
are:
a. Accumulated phosphorous as a consequence of the use of phosphoric
fertilizer are posing a serious threat as residues in domestic water supply and
for an ecology of rivers and other water bodies. Increased level of
phosphates in different water results in eutrophication.
b. Effect of chemical fertilizer is long-term, and therefore leads to a net loss
of soil organic matter.
To control insects, pests, diseases and weeds which are responsible for
reduction in productivity different chemicals are used as insecticides,
pesticides and herbicides. Successful control of insects, pests and weeds
increases productivity and reduces losses and provides security for harvest
and storage. Applications of these synthetic chemicals have great economic
values and at the same time cause a number of serious problems such as:
a. Affects human health which includes acute poisoning and illness caused
by higher doses and accidental exposes
b. As long-term effect, causes cancer, birth defects, Parkinson’s disease, and
other degenerative diseases.
c. Long-term application of pesticides can affect soil fertility.
d. Danger of killing beneficial predators.
e. Pesticides resistance and pest resurgence
Water Logging
High water table or surface flooding can cause water logging problems.
Water logging may lead to poor crop productivity due to anaerobic conditions
created in the soil. In India, deltas of Ganga, Andaman and Nicobar Islands
and some areas of Kerala are prone to frequent water logging.

Salinity
Due to adoption of intensive agriculture practices and increased
concentration of soluble salts leads to salinity. Due to poor drainage,
dissolved salts accumulate on the soil surface and affects soil fertility. Excess
concentration of these salts may form a crust on the surface which may be
injurious to the plants. The water absorption process is affected and the
uptake of nutrients is disturbed. According to an estimate, in India, 7 million
hectare of land is saline and the area is showing increasing trends due to the
adoption of intensive agriculture practises.
Case Studies
A study on birth defects in water birds, in Kesterson wildlife refuge in
California, indicated that these defects were due to a high concentration of
selenium.
Recent reports from the cotton-growing belt of Punjab which covers Abohar,
Fazalka and part of Bathinda indicates that the overuse of pesticides to
control insect pest in cotton to enhance productivity has not only affected
soil health but also caused cancer in human being.
Diclofenac is the drug for veterinary use to treat the livestocks which have
strong residual nature, which leads to high persistence throughout the food
chain. Due to bio-magnification it becomes more dangerous to the vultures
as they are consumers of diclofenac treated cattle. Diclofenac is responsible
for bringing three South Asian species of Gyps vultures to the brink of
extinction. It has been banned in India since 2006.