Energy ResourcesRenewable Energy Sources Renewable sources of energy or flow sources, rely on natural energy flows and sources in the environment and thus have the potential of being continually replenished. These include firewood, petroplants, animal dung, solar energy, wind energy, geothermal energy, tidal energy, etc.Non-renewable Energy Sources Non-renewable energy sources are available in limited amount and develop over a longer period. Because of indiscriminate use they are likely to be exhausted in the near future. These include coal, mineral oil, natural gas, nuclear power, etc.
Geothermal plants make use of naturallyheated steam drawn to the surfacethrough a series of bore holes about 1 Kmin length. It should be noted that geothermalenergy can be depleted unless existingfields are carefully managed. This energy is used in the form ofelectrical energy, thermal energy, nuclearenergy, light energy, mechanical energy &chemical energy etc
Advantages of solar energy:Solar energy iskind of universal, decentralized and no –polluting energy. Solar energy is the energy of the sun, whichreaches earth in the form of short waveradiation visible light and near ultraviolet light.Solar energy helps considerably in maintainingthe ecological balance through the process ofphotosynthesis and green house effect. Solar energy is bound to achieve greateconomic importance in future because ofdepletion trend of convention energy sources.
Land ResourcesThe Importance of Land• The human civilization has thrived on land.• Land is used for agriculture.• Land contains huge amount of mineral deposits.• It also contains water in the form of underground water.• Most of the animals find their habitat on land.• Land directly or indirectly provides all the resources required to fulfil the basic needs of humans: food, cloth, and shelter.
Land DegradationLowering of the quality of land is commonly referred to as land degradation.Causes of Land Degradation •Mining •Urbanization •Deforestation •Overgrazing •Construction of dams and canals •Excessive use of fertilizers •Dumping of industrial and domestic waste
Forest Resources A forest is a biotic community with a predominance of trees; it is an important renewable resource. Forests restore oxygen in our atmosphere through photosynthesis and also provide solvents, medicines, fuels, and many other products that are important for our health and comfort. India is rich in forest resources with a great diversity of flora and fauna.
Conservation of forests :- Forests can be conserved by :- i) Afforestation – planting of more trees. ii) Preventing or reducing deforestation.iii) Preventing over grazing by cattle.iv) By setting up wildlife sanctuaries, national parks, biosphere reserves etc. v) Undertaking social forestry programs like Van Mahotsav, Chipko movement for planting and protecting trees on a large scale.
Effects of Desertification•Rapid soil erosion•Poor soil quality•Unfavorable climate•Low water table, salty and hard water•Huge economic losses
Control of Desertification•Promoting large-scale plantation of trees•Changing agricultural practices and promoting dry land farming•Development of pasture lands and control of overgrazing•Promoting equitable use of water resources•Development of water catchment areas
Wildlife :-a) Importance of wildlife :- i) Wildlife helps to preserve biodiversity. ii) Wildlife helps to maintain food chains and food web.iii) We get useful products from wildlife like food, medicines, leather, bones, honey, lac etc.b) Conservation of wildlife :- i) Preserving the natural habitats of animals. ii) Banning poaching of animals.iii) Protecting endangered species of animals.iv) Setting up of wildlife sanctuaries, national parks, biosphere reserves etc.
Water :-a) Uses of water :- Water is a basic necessity for all living things. We use water for ourdaily needs, for agriculture, transportation, construction of buildings,roads, dams etc. Water is a natural habitat for aquatic organisms. Human activities are affecting the availability of water and causingpollution of water bodies.b) Dams :- Advantages of dams :- i) Irrigation of crops. ii) Producing electricity.iii) Supplying water to towns and cities.iv) To control floods. Disadvantages of dams :- i) Social problems :- It displaces a large number of people who have to be rehabilitated. ii) Economic problems :- It is expensive and uses a huge amount of public money.iii) Environmental problems :- It causes deforestation and loss of biodiversity.
c) Water harvesting (Rain water harvesting) :- Water harvesting is collecting and storing rain water for future use. The common methods of water harvesting are :- i) Digging pits, ponds, lakes etc. ii) Building small earthen dams or concrete check dams.iii) Construction of dykes.iv) Construction of reservoirs. v) Construction of rooftop collecting units in houses.d) Advantages of underground water :- i) It does not evaporate easily. ii) It spreads out and recharges wells.iii) It provides moisture for irrigation of crops.iv) It does not get polluted easily.v) It does not provide breeding ground for mosquitoes and houseflies.
Pollution – Acid Rain Sulphur and nitrogen compounds react with water and other substances in the air to form sulfuric acid and nitric acid. Acid precipitation removes calcium, potassium, and other nutrients from the soil, depriving plants of these nutrients. It damages plant tissue and slows their growth. Sometimes, the acid concentration is so high in lakes, rivers, and streams that fish and other organisms die.
Pollution - Eutrophication Eutrophication occurs when fertilizers, animal wastes, sewage, or other substances rich in nitrogen and phosphorus flow into waterways, causing extensive algae growth. The algae use up the oxygen supply during their rapid growth and after their deaths during the decaying process. Other organisms in the water suffocate. Eutrophication is a natural process, but human activities have accelerated the rate at which it occurs.
Methods of Controlling Soil Erosion•Reduced tillage•Contour bunding•Vegetative bunds•Strip cropping•Terracing•Afforestation on barren land•Control of overgrazing•Construction of small check dams•Promotion of equitable use of water resources•Prevention of excavation of rocks
Coal and petroleum :- Coal and petroleum are fossil fuels formed by the decomposition ofdead plants and animals inside the earth after several millions of years.They are non-renewable sources of energy. Petroleum reserves may last for about 40 years and coal reservesmay last for about 200 years. Coal and petroleum contain carbon, hydrogen, nitrogen and sulphur.When they are burnt, they release carbon dioxide and oxides ofnitrogen and sulphur. Carbon dioxide is a green house gas which causes global warming. Oxides of nitrogen and sulphur combines with moisture in the airand produces acid rain.
Control of Deforestation•Mining activities should be prohibited in areas declared as protectedforests.•Cutting of trees should be followed by massive plantation.•The environmental laws and legal provisions should be strictlyenforced.•Forest extension should be carried out through social forestry, agroforestry, recreation forestry, extension forestry, etc.•Public awareness should be created regarding medicinal and othereconomic and environmental significance of forests.
Role of an Individual in Conservation of Natural Resources •Energy Conservation Switch off electric lights and appliances whenever not needed Ride a bicycle as often as possible Using CFL bulbs energy can be saved. •Forest Conservation Plant a large number of trees Make equitable use of forest and forest products •Water Conservation Repair leakages Save water in agriculture (by adopting drip irrigation techniques)and domestic activities Adopt rainwater harvesting techniques •Land Conservation Do not dump agricultural, industrial, and domestic waste on land •Sustainable Food Adopt vegetarian food habits Use unpackaged food items such as vegetables and dry beans instead of canned or packaged food
Need for management of natural resources :- All the things we use and consume are obtained fromnatural resources. Due to increase in population,industrialisation and urbanisation the demand for naturalresources is increasing and their availability is limited . Sothere is a need for proper management of natural resources. The proper management of natural resources consists of :- i) Judicious use of natural resources and avoiding wastage of natural resources. ii) Long term planning for the use of natural resources so that it last not only for the present but also for future generations.iii) The exploitation of natural resources should not be for the benefit of a few people but should be distributed equally for all.iv) While extracting and using natural resources we should also plan for the safe disposal of wastes so that no damage is caused to the environment.
The Three R’s to save the environment :- The three R’s to save the environment are Reduce, Recycle and Reuse.i) Reduce :- means using less of natural resources and avoiding wastage of natural resources.ii) Recycle :- means the materials like paper, plastic, glass, metals etc used for making things can again be used for making new things instead of synthesising or extracting new paper, plastic, glass or metals.iii) Reuse :- means using things again and again like the plastic bottles in which we buy jams, pickles etc can be again used for storing things in the kitchen.