environmental resources

CHAPTER 2

NATURAL RESOURCES AND THEIR CONSERVATION

Natural Resources

Natural resources are the substances which are inherent to earth and

obtained from nature and utilized to create products and services which

are useful for human beings. Forests, water, air, soil , etc. are natural

resources.

Renewable and Non Renewable Natural Resources

The resources that can be harvested continuously with proper

planning and management are called renewable resources. Example:

plants, animals, solar energy , wind energy, etc.

Non Renewable resources are natural resources which are limited in

supply and cannot be replenished by natural means. Once exhausted,

they have very little chance of recovery or resynthesis. Coal, minerals,

petroleum, etc. are Non Renewable resources.

Chief Natural Resources

Forests Resources

Water Resources

Land Resources

Mineral Resources

Energy Resources

Food Resources

Forest Resources

A forest , a biotic community with

predominance of trees is an important

Renewable natural resource.

Benefits of Forests

Protective FunctionForest Provide protection against Soil erosion, Droughts, floods, noise, radiations

Productive FunctionForest Provide various products like, gum resins, medicines, Katha, honey, pulp, bamboo, timber, and fruits

Regulative FunctionThe Forest regulates the level of Oxygen and carbon dioxide in atmosphere. The forests also help in regulating temperature conditions

Accessory Function Forest provides aesthetics, habitat to various flora and fauna besides that it also has an recreational value

Deforestation

Deforestation is removal or reduction in forest cover. •Encroachment of forest land for agricultural purposes•Expansion of cities.•Construction of dams, canals and highways•Establishment of industrial areas•Demand for firewood•Mining•Shifting Cultivation•Forest Fires

Effects of Deforestation

Large scale of destruction of forests leads to a number of adverse environmental effects.

•Loss of natural habitat of wild animals and plants•Increased intensity and frequency of natural disasters•Land Degradation•Loss of forest products•Change in climatic conditions•Siltation of rivers and canals•Loss of revenue•Change in water cycle and reduced rainfall•Increase socio economic problems

Deforestation

http://www.youtube.com/watch?v=aHU2o7y7BIQ

Water Resources

SOURCES OF WATER

Ground water

Surface water

Aquifer

An aquifer is an underground layer of water bearing permeable

rock or unconsolidated materials from which ground water can be

usefully extracted using water well. Aquifers

are of two kinds :

Confined Aquifer

An aquifer which is sandwiched between two layers of less

permeable materials.

Unconfined Aquifer

Aquifers having water table in it are called unconfined aquifers.

Effects of Over Utilization of Ground water

Sharp decline in water table

Loss of vegetation and wildlife habitat.

Water logging and salinity problems.

Ground subsidence.

Water Calamities: Floods and Droughts

Floods

Floods refers to the presence of unusually large amount of

water at any place or more water that can be handled by the

drainage of the area. The various types of floods are

Flash Floods

River floods

Coastal Floods

Drought

A drought is a condition in which a region suffers from a severe scarcity in its water availability.

The various kinds of drought are

Meteorological Drought

Hydrological Drought

Agricultural Drought

Dams: Benefits and Problems

What do dams provide ?

Electricity

Irrigation

Navigation

Flood Control

Beautiful landscape

Demands for drinking and other consumption needs

Disadvantages of Dams

Deforestation and loss of biodiversity

Sinking of agricultural and forest land

Displacement of tribals from their home land

Growth of aquatic weeds

Siltation of reservoirs due to degraded catchment conditions

Increase in water borne and soil borne diseases

Increase flash floods

Increased water logging and salinity

Emissions of greenhouse gases

Mineral Resources

Minerals are naturally occurring chemical compounds, which are formed through inorganic processes under the crust of the earth.

Minerals are non-renewable resources

Types of Minerals

Metallic Minerals

Non-metallic minerals

Fuel Minerals

Environmental Effect of Extraction and over Exploitation of Mineral Resources

Destruction of forest

Soil erosion and reduces soil fertility.

Generation of large amount of wastes

Pollution of air, water and land.

Mining lowers water table

Occurrence of Earthquakes and volcanic events

Occupational health hazards

Emission of radioactive pollutants, ash and trace metals.

Mining

http://www.youtube.com/watch?v=ijEfthxHe0w

Food Resources

Natural or artificially produced materials, which are used as food to

derive metabolic energy, are called as food resources.

Type of Food1 Agricultural Crops2 Livestock3Fish4Others(Mariculture based)

World Food Problems

Insufficient production

Lack of irrigation facility

Under nutrition and malnutrition Hoarding and black-marketing

Causes of Food Problems

Increased Population

Unfavorable Climatic Conditions

Adverse geographical Conditions

Infertile soil

Disasters such as Floods, drought, earthquakes, storms, etc.

Starvation and malnutrition

Lack of transportation

High cost of grains

Insufficient distribution system

Environmental Effects of Modern Agriculture

Soil Erosion

Change in Land use Patterns

Water Logging and Salinity

Impact of Chemical Fertilizers and Pesticides

Water and Land Pollution

Loss of genetic Diversity

Sustainable agriculture: the need of the hour

Sustainable Agriculturehttp://www.youtube.com/watch?v=npdd6DV0t7s

Energy Resources

All living creatures on the earth, either it is a plant, an animal or a

microbe need energy to perform their vital functions. The earth is

a storehouse of energy. The fossil fuels under its surface, the wind

and water on its surface, the plants growing on it, the sunlight

falling upon it, these are all sources of energy.

Renewable Sources of Energy Non Renewable Sources of Energy

Solar Energy Coal

Wind Energy Natural Gas and Oil

Tidal Energy Nuclear Energy

Geothermal Energy

Biomass Based Energy

Land resources

‘The solid portion of the earth’s surface’.

The science dealing with land is known as pedology .

Land Degradation

The fertility of land supports the growth and productivity of

natural vegetation and agricultural crops. A number of

natural and man-made factors lower the quality of land. This

is commonly referred to as land degradation.

Causes of land degradation

•Heavy rains•High speed wind and storms•Natural disasters like earthquakes ,floods, prolonged drought, etc.•Overgrazing, soil erosion ,etc.. •Mining.•Urbanization•The indiscriminate and uncontrolled removal of trees•Excess use of fertilizers•industrial discharges

Soil Erosion

Soil erosion is removal of top soil from its resting place by various

physical agencies like wind and water. It can be defined as “the

detachment and transport of the fertile layer of soil by water or

air.” It is also known as the creeping death of land.

Causes of Soil Erosion

Large scale deforestation

Floods

Overgrazing

Large Violent Winds

Improper agricultural techniques

Strip croppingContour bunding

Terracing

Methods to control Soil Erosion

Afforestation

Construction of small check dams

Methods for conservation of natural resource, and control 1Establishment of organizations.2Create Act/Rules3Public Awareness4Use of 3R System5Use of scientific methods and Technology.6Follow the Disaster Management system.

Role of an Individual in Conservation of Natural Resources

Use recyclable resources like reuse paper page and encourage recycling.

Use alternative energy sources such as solar energy for domestic heating

Make equitable use of water for personal and domestic purposes.

Through better use and maintenance of non-maintainable resource.

Prefer to use renewable and non-conventional energy sources.