Natural resources

B PHARMACY 2ND SEMESTER

1. Panipat Institute of Engineering and Technology Course :B Pharmacy Subject – Environmental Sciences Subject Code BP206T NATURAL RESOURCES Suman Assistant Professor, PIET

2. DEFINITION:- NATURAL RESOURCES DEFINITION:- A natural resource may be defined as any material given to us by nature which can be transformed in a way that it becomes more valuable and useful. Eg:- Wood is used for making furniture Yarn from cotton for weaving clothes

3. Classification of Natural Resources Based on Origin: . BIOTIC: (living organisms) ABIOTIC: (non living organisms) Based on Availability: Inexhaustible: (replenishes naturally) Exhaustible: (replenishing process is extremely slow) Based on Distribution: Omni present: (found everywhere) Location based: (found at some specific locations only Based on Source: a. Water Resources Forest Resources Mineral Resources Marine Resources Based on Chemical Composition: organic: (vegetables, animals, bacteria, mineral oil) Inorganic: (Air, water, minerals) c. mixed: (land)

4. Renewable resources:- Resources which can be renewed along with their exploitation always available or use. Hence they are called as renewable resources. Eg:- solar energy and wind energy. Non-renewable:- The formation of some resources like iron ore, mineral, etc., has taken several thousand years. Once 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 or exhaustible.

5. FOREST RESOURCES:- Derived from Latin word foris meaning outside, the reference being to villages boundary or fence and must have included all uncultivated and un inhabited Natural ecosystem having multi species and multi aged trees as dominant community Forest area in India At the beginning of the 20th century about 30% of land in India was covered with forests. by the end of the 20th century the forest cover was reduced to 19.4% Of the existing forests, less than two-third are dense forests, and the rest are open degraded forest. Today, per capita forest area available in India is 0.06 ha, which is much below the average for the world (0.64 ha per person).

6. FOREST RESOURCES: Functions of forest resources ; Productive functions, include production of wood, fruits and a wide variety of compounds, such as resins, alkaloids, essential oils, latex, pharmaceuticals, etc. Protective functions, include conservation of soil and water; preventing drought, sheltering against wind, cold, radiation, noise, sights and smells, etc. Regulative functions, involve absorption, storage and release of gases (CO2, O2), water, mineral elements and radiant energy. Such regulative functions improve atmospheric and temperature conditions, and enhance the economic and environmental value of the landscape. Forests effectively regulate floods and drought, and the global biogeochemical cycles, particularly of carbon. Accessory functions: recreation, aesthetic and habitat of diverge wild life

7. FOREST RESOURCES:- Importance of forest resources ; Ecological balance:- Forests and wildlife are essential to maintain ecological balance of an area. Renewable natural resources:- Forests are an important renewable natural resources. Eco-system:- Trees dominate forest ecosystem; their species content varieties in different parts of the World. Economic development:- Forest contributes to the economic development of the country because they provide goods and services to the people and industry. Environment quality:- the forest enhance the quality of environment by influencing the life supporting system.

8. Continued:- Safeguard against pollution:- Forest check air pollution and soil erosion. Thus, they exercise safety and against pollution. Soil conversation:- Forest save the hill slopes from landslides. Wind erosion:- In deserts, trees reduce wind erosion by checking wind velocity. Check the extension balance:- the forest check strong gales and keeps the soil intact beneath the roots of trees and thus checks extension of desert. Maintains ecological balance:- the forest check strong pollution of air through increasing oxygen content of the air. Attract rainfall:- by causing condensation of water vapour in clouds, forest attract rains.

9. Continued:- Control floods:- the floods are controlled because forests are linked with our cultural and civilization. Linked with cultural and civilization:- Forests are linked with our culture and civilization Supply of raw materials:- forest supply wood, which is used under fuel, raw material for various industries as pulp, paper, newspaper, board, timber for furniture items, to be used in packing articles like fruits, tea, for preparing matches, sports goods etc., Minor forest products:- some examples of minor forest products are canes, gums, resins, dyes, flocks, medicines, tannins, lac, fibers, katha etc,. For tribal people are provided with tuber, roots, leaves, fruits, meat from birds and other animals etc,,

10. Continued:- Employment opportunities:- About eight crore people are employed in wood based industries like paper and match and small and cottage industries. Besides, those who are employed in the forest department in various states. Revenge receipts:- The forest provide Rs.400 crore for per year as revenue to the government. Fodder for cattle:- forest provide fodder to cattle. Foreign exchange earners:- forest produce a great number of articles like essential oils, resins and dyes which find market in foreign countries. Nearby Rs.50 crores are earned in foreign exchange through selling lac, turpentine, oil and sandal wood oil to abroad. Thus, forests are useful to us directly and indirectly.

11. Distribution of Forests The western Himalayan region The Eastern Himalayan region The Assam region the ganga plain region the deccan region the malabar region the andaman region

12. Reasons for Deforestation For obtaining raw materials for industry. For obtaining timber for furniture and construction work. -For obtaining fire wood. For developing the mineral industry. For constructing projects on rivers. For expanding Agricultural land. For the purpose of constructing the roads. For establishing industries. For the construction of railway tracks. Human accommodation. Over grassing of forest by live stocks. Destruction by insects and pests. Forest fires. Extreme weather conditions

13. Threats associated with Deforestation : 1. Increase in the possibilities of flash floods. 2. Decrease in the rain fall. 3. Increase in the atmospheric temperature. 4. Increase in the amount of soil erosion. 5. Migration of tribal population leads to mental frustration. 6. Extinction of some useful medicinal species. 7. Shelter problem for forest animals will increase. 8. Problem of urbanization will arise. 9. Atmosphere will become adverse. 10. Desertification of forests and agricultural land. 11. Forest dwellers will have a problem of survival. 12. Decrease in the population of animal species. 13. Increased chances of cyclone due to climate change

14. Need and measures of Forest Conservation : Needs : 1. To maintain equilibrium in Ecosystem. 2. To maintain Bio-diversity. Measures: 1. Forest fires should be prevented. 2. Use of pesticides to eliminate the risk of pests. 3. Plantation of resistant varieties. 4. Replacements of trees (aforestation) 5. Replacing the fire woods by biogas and solar cooker. 6. Implementation of social forestry programmes. 7. Aforestation programmes should be undertaken on wastelands. 8. Trees of aesthetic value should be planted. 9. Renewal of forest crops. 10. Reforestation by suitable monoculture. 11. Unwanted felling of trees should be restricted

15. Water resources Water claims to be an important resource. An important use of water in our country is for irrigation. Besides, water is also required in large amounts for industrial and domestic consumption. SIGNIFICANCE OF WATER Several cities and civilization have disappeared due to water shortages originating from climatic changes. Millions of people all over the world, particularly in developing countries, losing their lives every year from water-borne disease. helps to regulate climate, water falls,tides,river currents and generation of power water covers ⅘ part of earth i.e. 1.4 billion cubic kilometers, 3% (fresh water), 97% ocean water

16. Sources of water Water in the oceans underground water water onland water in atmosphere water in the biosphere UNDERGROUND WATER Aquifer: Layers of highly permeable rock that can store water is called an aquifer. Layer of sand and gravels are good aquifers. Clay and crystalline rocks are not good aquifers. Effects of over utilization of water 1. Decrease of groundwater: Increased usage decreases the ground water. Insufficient rain fall Building construction activities sealing the permeability of the soil. 2.Ground subsidence: If ground water withdrawal is greater than it’s recharge rate, then the sediments in the aquifers get compacted. As a result shrinkage of land surface takes place. Problems: a. Structural damages to the buildings b. Fracture in pipes. c. Reversing the flow of canals.

17. Continued Ground Water 3. Lowering of water table: Over utilization of ground water in arid and semi arid regions for agriculture disturbs the state of equilibrium of the hydrological cycle. Problem: a. Decrease the number of aquifers b. Change the speed and direction of water. 4. Intrusion of saltwater: In coastal area over exploitation of ground water leads to the intrusion of salt water from sea. Therefore that water cannot be used for drinking and agriculture. 5. Over utilization of water causes earth quakes, landslides and famines. 6. Drying up of wells: Due to over utilization, ground water level decreases much faster than can be regenerated. It leads to drying up of dug well and bore wells. 7. Pollution of water: Near the agricultural land ground water decreases therefore water containing nitrogen enters into the ground and pollute the ground water. Problem: Water which contains excess nitrate content is not suitable for drinking

18. REASONS FOR DECLINE OF GROUNDWATER 1. Population explosion 2. Overutilization of Surface and Groundwater 3. Deforestation: 4. Hydropower generation 5. Dams 6. Rainfall 7. India’s increasing demand for water for intensive irrigated agriculture, for generating electricity, and for consumption in urban and industrial centers, has been met by creating large dams. Dams support 30 to 40% of this area.

19. FLOOD It is an over flow of water. It happens when the magnitude of flow of water exceeds the carrying capacity of the channel within its bank. CAUSES OF FLOOD 1. Heavy rainfall, melting of snow and sudden release of water from dams. (Flash floods) 2. Reduction in the carrying capacity of the channel. 3. Deforestation, mining and overgrazing increase the runoff from rains and the level of flood raises. EFFECT OF FLOOD 1. Water spreads in the surrounding area and submerges them. 2. Cultivated land gets affected. 3. Extinction of civilization. FLOOD MANAGEMENT 1. Floods can be controlled by dams. 2. Channel management control flood. 3. Flood hazards reduced by forecasting or flood warning. 4. Flood may also be reduced by reduction of run off by increasing infiltration through appropriate afforestation in the catchment area.

20. DROUGHT scarcity of water, Reasons 1. Inadequate rain fall 2. Late arrival of rain fall 3. Excessive withdrawal of ground water. Lack of water for the needs of agriculture, livestock, industry or human population may be termed as a drought. Drought causes serious damages to plants, animals and human life. CAUSES 1. When annual rain fall is below normal and less than evaporation, drought is created. 2. High population. 3. Intensive cropping pattern.

21. EFFECTS OF DROUGHT 1. Drought causes hunger, malnutrition and scarcity of drinking water and also changes the quality of water. 2. Drought causes widespread crop failure leading to acute shortage of food and adversely affects human and live stock population. 3. Worst situation of drought causes desertification. 4. Raw materials of agro based industries are critically affected during drought time, hence industrial and commercial growth decreases. 5. Drought increases the degradation of natural resources. 6. Drought causes large migration of people and urbanization. DROUGHT MANAGEMENT 1. Indigenous knowledge is essential. 2. Rain water harvesting system. 3. Construction of reservoirs to improve ground water level. 4. Modern irrigation technology (drip irrigation) very useful to conserve water. 5. Afforestration activities also improve the potential of water in the drought area. 6. Crop mixing and dry forming are the suitable methods which minimize the risk of crop failures in dry area.

22. SUSTAINABLE WATER MANAGEMENT Building several small reservoirs instead of few mega projects Developing small catchment dams and protecting wetlands Soil management, micro-catchment development and afforestation permits recharging of underground aquifer, thus reducing the need for large dams Treating and recycling municipal waste water for agricultural use. Preventing leakages form dams and canals and loss in municipal pipes Effective rainwater harvesting in urban environments Water conservation measures in agriculture, such as using drip irrigation, control of growing water intensive cash crops ; control of water logging. Pricing water at its real value makes people use it more responsibility and efficiently and reduces wastage In deforested areas where land has been degraded, appropriate soil management practices, making bunds along the hill-slopes and making nalla plugs can help retain moisture and make it possible to revegetate degraded areas Use waste water for activities that does not need fresh water – Recycling

23. SUSTAINABLE WATER MANAGEMENT Adopt mini water harvesting models for domestic usage. Protect existing tanks Develop systematic water management and adopt strict water auditing “Save water Campaigns” for public awareness on water scarcity Through rainwater harvesting, community based participatory initiatives and holistic watershed management. Responsible water usage can only be achieved by empowering local communities and creating local accountability. The government should develop policies that protect water resources, promote sustainable watershed management and invest in technologies that will increase efficiency in irrigation, industrial usage and improve water harvesting techniques.

24. MINERAL RESOURCES Significance: The economic development of a country depends to a great extent. On the availability of minerals get as over from the earth by mining coal and iron are the basic minerals which man needs to develop iron and steel industry. Minerals like mica, copper, lead and zinc are of vast economic importance. Thorium and uranium are atomic energy minerals. Need for appropriate policy Finite and non renewable resources constitute raw materials for basic industries major resources for nation development National mineral policy mineral exploration proper linkage between exploitation of minerals and developments of mineral industry protection from adverse effect of mining enforcement of mining plan optimum utilization, export and recycle

25. USES AND EXPLOITATION OF MINERALS 1. Development of industrial plants and machinery. - Fe, Al & Cu 2. Construction work – Fe, Al & Ni 3. Generation of energy - coal, lignite, uranium 4. Designing defense equipments like weapons and ornaments 5. Agricultural purposes – fertilizers and fungicides – Zn & Mn 6. Jewellery –Au, Ag & Pt 7. Making alloys for various purposes 8. Communication purposes – telephone, wires, cables and electronic devices 9. Medicinal purposes, particularly in ayurvedic system

26. Peculiar characteristics Exhaustibility localised occurrence unpredictable occurrence risk involvement dependence on other factors

27. ENVIRONMENTAL DAMAGES CAUSED BY MINING ACTIVITIES 1. Devegetation: Topsoil and vegetation get removed. Landscape gets badly affected 2. Groundwater contamination: Mining pollutes groundwater; sulphur is converted into sulphuric acid which enters into the soil. 3. Surface water pollution: Radioactive wastes and other acidic impurities affect the surface water, which kills many aquatic animals. 4. Air pollution: Smelting and roasting are done to purify the metal which emits air pollutants and damage the nearby vegetation. It causes many health problems. 5. Subsidence of land: Mainly underground mining results in cracks in houses, tilting of buildings and bending of rail tracks Conservation 1. efficient method of mining 2. use and reuse of scraps 3. substitute the use of rare and costly minerals with abundant and cheaper minerals 4. recover all associated elements as coproducts

28. FOOD RESOURCES Food is an essential requirement for survival of life. Main components are carbohydrates, fats, proteins, minerals and vitamins TYPES OF FOOD SUPPLY 1. Crop plants: Grains mostly constitute about 76% of the world’s food. Ex: Rice, Wheat and Maize 2. Range lands: Produces 17% of world’s food from trees and grazing animals. Ex: Fruits, milk and meat 3. Ocean: Fisheries – 7% of world’s food WORLD FOOD PROBLEM 1. In the earth’s surface, 79% is water out of total area. 21% land (forest, desert, mountain and barren land) . Less % cultivated land, at the same time population explosion is high therefore world food problem arises. 2. Environmental degradation like soil erosion, water logging, water pollution, salinity affects agricultural land. 3. Urbanization affects agricultural land. Hence production of rice, wheat, corn and other vegetable is difficult.

29. FOOD PROBLEM: 1.Quantitative aspect of food problems: a)Increasing population: Though food production has increased all over the world as well as in India, yet due to over growth of population our needs also have increased for greater than the production. b)Secondary, man off and no suffer from the droughts and floods. This is the reason why the prices of food grains are shooting up. 2. Qualitative aspects of food problem: (i)Less production of protective food. (ii)Low capacity for the purpose of nutritious articles. (iii)Refraining from meat, fish and eggs due to religios causes. (iv)Unawareness of balanced diet.

30. 3. Distribution of aspects of food problem: Distribution of food grain is far from beginning satisfactory. It is essential that the available food grains in the country should be distributed to public at four-price and appropriate time. It is worth mentioning that our government has taken up proper measures in this direction. It’s role as an anti-inflammatory measure has also been recognized. The system is designed. 4. Economic aspect of food problem: The price of food grains is soaring high while income has no proportionate increase. Hence, poor people are unable to avail two meals a day.

31. Causes Long term population growth decrease in agriculture output decrease in productivity insistence of commercial agriculture mid-term position of 1947 defective food distribution fall in purchasing capacity limited jurisdiction of reserve bank short term increase in consumption level deficit in production anti-social activities transportation

32. Environmental effects loss in biodiversity due to habitat loss when natural systems like forests and grasslands are cleared, or wetlands are drained, for establishing agricultural fields. Replacement of thousands of wild varieties of crop plants with fewer high yielding varieties (as in green revolution) causes loss in genetic diversity. Inadequate safeguards in agriculture may lead to soil erosion and decreased soil fertility, and in extreme cases even waterlogging, salinization and desertification Excessive employment of farm machinery causes increased air pollution and greenhouse gas emission from the fossil-fuel used. Heavy use of pesticides (often having long persistence in soil) in industrialized agriculture results in pollution of air, water as well as soil. Pesticides may kill fishes and contaminate drinking water. Similarly, substantial fraction of heavy fertilizer inputs may be leached causing water pollution (e.g. high nitrate contamination of drinking water).

33. OVERGRAZING It is a process of eating the forest vegetation without giving a chance to regenerate. EFFECTS OF OVERGRAZING 1. Land degradation Overgrazing removing the cover of vegetation Exposed soil gets compacted Soil moisture reduces. Desertification - OG leads to poor, dry and compacted soil. Land cannot be used for further cultivation. 2. Soil erosion: When the grasses are removed the soil becomes loose and gets eroded by the action of wind and rain fall. 3. Loss of useful species: OG affects the plant population and their regenerating capacity. OG replace the plant of high nutritive value with plant of low nutritive value.

34. AGRICULTURE Agriculture is an art, science and industry of managing the growth of plants animals for human use. It includes cultivation of the soil, growing and harvesting crops, breeding and raising livestock, dairying and forestry. TYPES OF AGRICULTURE 1. Traditional agriculture 2. Modern (or) industrialised agriculture 1. Traditional agriculture Small plot, simple tools, surface water, organic fertilizer and a mixture of crops constitute traditional agriculture. They produce enough food to feed their family and to sell it for their income. 2. Modern agriculture Hybrid seeds of single crop variety, high tech equipments, lot of fertilisers, pesticides and water to produce large amount of single crops. EFFECTS OF MODERN AGRICULTURE Beneficial effects of fertilizers Increase in food production improvement of soils in temperature areas enhancement in water and efficiency of crops

35. Problems in using fertilizers a. Excess of fertilizers causes micronutrient imbalance. (e.g) Punjab and Haryana deficiency of nutrient zinc in the soil affect the productivity of the soil. b. Blue baby syndrome (nitrate pollution): Nitrate present in the fertilizer causes blue baby syndrome, when the amount exceeds the limit leads to death. c. Eutrophication: Nitrogen and phosphorus in the crop fields washed out by runoff water in the water bodies, which increases the nourishment of the lakes called eutrophication. Hence algal species increases rapidly. Life time of the species is less and they decompose easily and pollute the water which affects the aquatic life. d. stimulation of weed growth in crop fields e. disturbance in the ionic balance and equilibrium in soils Problems in using pesticides 1. Death of non target organism. 2. Producing new pest – super pest 3. Biomagnification – Most of the pesticides are non biodegradable, keep on concentrating in the food chain and it is harmful to human beings. 4. Risk of cancer: a. It directly acts as carcinogen b. It indirectly supports immune system.

36. 3. Water logging: Land where water stand for most of the year. it results in damage to or death of roots Causes of water logging: 1. Excessive water supply 2. Heavy rain 3. Poor drainage Remedy: 1. Preventing excessive irrigation 2. Subsurface drainage technology 3. Bio drainage like trees like Eucalyptus 4. Salinity in agriculture high concentration of inorganic salts in land (Saline land or kallar soils),

37. ENERGY RESOURCES Energy is defined by physicists as the capacity to do work. aims at human welfare covering household,agriculture,transport and industrial complexes Energy is found on our planet in a variety of forms, some of which are useful to do work immediately, while other require a process of transformation. (e.g. chemical energy by all living organisms) TYPES OF ENERGY RESOURCES: Renewable/inexhaustible renewed over a very short period of time available in unlimited amount in nature can be harvested through a sustained proper planning and management reproduce themselves fire wood, animal dung, solar energy, hydropower, wind energy Non renewable/exhaustible available in limited amount, develop in longer period of time mght finish off due to excess use coal.mineral,petroleum,natural gas (fossil fuel,organic nature)

38. C onventional and non-conventional energy resources Conventional energy resources: Primary :Coal, lignite, bituminous coal secondary : petroleum products, diesel, petrol Non-conventional energy resources: solar power,tidal power,geothermal power, wind power, biomass energy

39. Solar energy: Nuclear fusion reaction of sun produces enormous amount of energy. can be used directly or indirectly for human welfare. Direct solar energy is the radiant energy indirect solar energy is energy obtained from materials that have previously incorporated the sun’s radiant energy. l Several techniques are available for collecting, storing and using solar energy. a. Solar cell (or) Photovoltaic cell (or) PV cell: Solar cell consists of p- type semi conductor (Si doped with B) and n-type semi conductor (Si doped with P). P-type forms top layer and n-type forms bottom layer. Solar rays fall on the top layer, the electrons from valence band promoted to the conduction band which crosses the p-n junction into n-type semi conductor. Potential difference between the two layers is created which causes flow of electrons. Uses: It is used in calculators, electronic watches, street light, water pumps etc. b. Solar battery: Large number of solar cells connected in series is called solar battery. It is used in remote areas where continuous power supply is a problem. c. Solar water heater: It consists of insulated box painted with black paint with glass lid. Inside the box black painted copper coil is present. Cold water is allowed to flow, it is heated up and flows out into a storage tank from which water is supplied through pipes.

40. Wind energy: Moving air is called wind. The energy recovered from the force of the wind is called wind energy It’s speed is high. a. Wind mills: When a blowing wind strikes the blade of the wind mill, it rotates continuously. And rotational motion of the blade drives number of machines like water pump, flour mills and electric generators. b. Wind farms: When a large number of mills are installed and joined together in a definite pattern – it forms wind farm. It produces large amount of electricity. Condition: Minimum speed for wind generator is 15 Km/hr Advantages: 1. It does not cause air pollution 2. Very cheap 3. Ocean energy: Tidal energy (or) Tidal power: Ocean tides are due to gravitational force of sun and moon which produce enormous amount of energy. High tides – rise of water in the ocean. Low tides – fall of water in the ocean. Tidal energy can be used by constructing a tidal barrage. During high tides sea water enters into the reservoirs and rotates the turbine, produce electricity. During low tides water from reservoir enters into the sea rotate the turbine produce electricity. Ocean thermal energy: Temperature difference between surface water and deeper level water in ocean generates electricity. The energy available due to the difference in temperature of water is called ocean thermal energy. Condition: Temperature difference should be 200C. Process: Ammonia is converted into vapours on the surface of warm water, it increases the vapour pressure which rotate the turbine and generates electricity. Deeper level cold water is pumped to cool and condense the vapour into liquid

41. Geo thermal energy: Temperature of the earth increases at a of 20 –750C per/km when we move down the earth. The energy utilised from the high temperature present inside the earth is called geothermal energy. Natural geysers: Hot water or steam comes out of the ground through cracks naturally is called natural geysers. Artificial geysers: Artificially a drill hole up to the hot region and by sending a pipe into it. The hot water or steam is used to rotate the turbine and generate electricity. Bio mass energy: Bio mass: Organic matter produced by plants or animals used as source of energy Bio gas: Mixture of methane, carbondioxide and hydrogen sulphide. Methane is the major constituent. It is obtained by anerobic fermentation of animal dung (or) plant wastes in the presence of water. Bio fuels: Fuels obtained by the fermentation of biomass. Ex: Ethanol, methanol Ethanol: Produced from sugar cane. Calorific value is less. Methanol: Obtained from ethanol Calorific value too less. Gasohol: Mixture of ethanol and gasoline India trial is going on to use gasohol in cars and buses. Hydrogen fuel: Hydrogen produced by pyrolysis, photolysis and electrolysis of water. It has high calorific value. Non polluting one because the combustion product is water. Disadvantages: 1. Hydrogen is highly inflammable and explosive. 2. Safe handling is required. 3. Difficult to store and transport.

42. NON RENEWABLE ENERGY SOURCES: Energy which cannot be regenerated is called as non-renewable. 1. Coal: It is a solid fossil fuel. Disadvantages: 1. When coal is burnt large amount of CO2 is released which causes global warming. 2. S, N produces toxic gases during burning. 2. Petroleum: Crude oil is a liquid consists of more than hundreds of hydrocarbons and small amount of impurities. The petroleum can be refined by fractional distillation. In the world level 25% of oil reserves are in Saudi Arabia. At present rate of usage, the world crude oil reserves are expected to get exhausted in just 40 years. 3. Liquefied petroleum gas (LPG): Petroleum gases obtained during FD and cracking can be easily converted into liquid under high pressure as LPG. It is colorless and odorless gas, but during cylindering mercaptans are added to detect leakage.

43. 4. Natural gas: These are found above oil in oil wells. It is a mixture of methane and other hydrocarbons. Calorific value is high. There are two types. Dry gas and wet gas 5. Nuclear energy: Dr.H.Bhabha is a father of nuclear power development in India. 10 nuclear reactors are present in India. It produces 2% of India’s electricity. Nuclear energy can be produced by two types of reactions. Nuclear fission and nuclear fusion. Nuclear fission; It is a nuclear change in which heavier nucleus split into lighter nuclei on bombardment of fast moving neutrons. Large amount of energy is released through chain reaction. Ex: Uranium with fast moving neutron gives barium and krypton in addition to three neutrons; in the second stage it gives nine neutrons and so on. This process of propagation of the reaction by multiplication is called chain reaction. Nuclear fission: It is a nuclear change in which lighter nucleus is combined together at extremely high temperature (1 billion 0C) to form heavier nucleus and a large amount of energy is released. Ex: Isotopes of hydrogen combine to form helium molecule.

44. LAND RESOURCES Earth’s one-fourth area is formed by land which is largely covered with natural forests, grasslands, wetlands, and man-made urban and rural settlements along with agriculture. Low lying areas covered with shallow water are called wetlands. The wetlands are transitional between terrestrial and aquatic areas. Soil is the upper weathered crust of earth which supports plant growth. In all land resources soil is of critical importance. Soil resource life zone of earth Soil is composed of inorganic particles, organic matter, air, water and, variety of organisms. any part of earth’s crust in which plants roots Components Minerals Humus Soil atmosphere Soil water Biological system Soil is a result of actions and reciprocal influences of parent rocks, climate topo\graphy,plants,animals and age of the land

45. LAND DEGRADATION Th e upper earth crust becomes unfit for human as well as animal habitation Reasons natural calamities or geological reasons like volcanic eruption, earthquakes or landslides Nuclear testing D eforestation Mining Desertification SOIL EROSION Removal of top soil from land Type of erosion D epending upon rate Normal geological accelerated

46. 2. depending upon cause due to climatic factors Water erosion wind erosion slip erosion riparian erosion ice erosion wave erosion b. due to biotic factors deforestation shifting cultivation EFFECTS OF SOIL EROSION loss of forest vegetation loss of soil fertility climatic changes flash floods siltation famine desertification

47. BASIC PRINCIPLES OF SOIL CONSERVATION Protection of soil from rain water prevent of flow of water on slopes (contour ploughing) slow down movement of water (terrace farming) facilitate percolation of water into the soil reduction of wind velocity give vegetation avoid overgrazing kallar soil should be reclaimed Desertification Desert formation due to a natural phenomenon linked to climatic change or due to abusive land use Causes the population explosion in man and livestock shifting agriculture revenue generation road construction industries and mining development projects commercial demand overgrazing

48. Role of individual in conservation of Natural Resources Conservation means management of the benefit of all life including humankind of the biosphere so that it may yield sustainable benefit to the present generation which maintaining its potential to meet the needs and aspiration of the future generations. objectives 1. M aintain essential ecological processes and life support system 2. preserve biological dividers 3. utilization of species and ecosystem is sustainable Types of conservation In Situ Conservation means maintenance of resources within natural habitats or ecosystem e.g. biosphere reserve, national parks, sanctuaries, nature reserves Ex Situ Conservation means maintenance of resources outside the natural habitat e.g. zoo, botanical garden, culture centre

49. Role of individual in conservation of Natural Resources less exploitation of resources control over population increase integrated and holistic approach in tackling environmental problem increase in plant cover proper use of water proper irrigation for soil conservation proper use of wood substitution of biomass for petroleun product use of solar energy