CONSERVATION OF NATURAL RESOURCES
Anything which is useful to man or can be transformed into a useful product or can be used to produce a useful thing can be referred to as a resource. A natural resource is the resource obtained from nature. It is these natural resources which form the basis of entire life on this planet. A natural resource can be of the following two types : living (biotic) or non-living (abiotic).
(1) Biotic resources : A resource is directly or indirectly derived from photosynthetic activity of green plants. Food, fruits, wood, fibre, milk, milk products, fish, meat and leather are termed as biotic resources. Coal, oil and natural gas are also biotic resources as they were produced by photosynthetic activity of plants which occurred millions of years ago.
(2) Abiotic resources : Mineral material, fresh water, rocks, salts and chemicals etc. are termed as abiotic resources as biological activity is not involved in their formation.
Types of natural resources : The natural resources can be classified into two categories :
(1) Inexhaustible resources
(i) The total amount of atmosphere, water, rocks and solar energy can never get exhausted.
(ii) Similarly solar energy is inexhaustible.
At present all the developing countries of the world have started to realize that there is a conflict between environment and development. The problems of human environment derive essentially from these factors :
(a) The first is the expansion at geometric rates of population.
(b) The second is a one-sided application of technology to achieve certain goals without the consideration of the effects of this technology on the human environment or on man itself.
(c) The third is the lack of control over the use of land.
(2) Exhaustible resources : They are natural resources with finite supply which if used indiscriminately are likely to diminish and then get exhausted. e.g., minerals, fossil fuels, forests, pastures, aquatic organisms. Exhaustible resources are of two types, renewable and nonrenewable.
(i) Renewable resources
Renewable resources are those resources which can be regenerated.
These are mostly biological in nature and include forestry, agriculture, animals (biomass-based) etc.
These can be reproduce itself in nature and we may harvest them continuously through a sustained proper planning and management. Solar energy, wind energy, water energy (tides) and geothermal energy belong to this category, since these are available in an inexhaustible form in nature.
(ii) Non-renewable resources
They are physical resources like coal, oil deposits, natural gas, minerals, soil, metals, etc. These are available in nature only in limited amounts and cannot be reproduced.
Coal, petroleum and natural gas are the common sources of energy. They, being of organic origin, are also called fossil fuels.
These account for 90% of the worlds production of commercial, energy, hydroelectric and nuclear power accounting for only 10%. The figures are :
Oil – 39.5%
Coal – 30.3%
Natural gas – 19.6%
Hydro-electric – 6.7%
Their formation requires millions of years which can not occur within the human scale of time. Similarly, metals and minerals come from deposits developed by a very slow process of geo-chemical concentration which look millions of years to form.
- Natural resources are also classified on the basis of their presence in different countries.
(1) National resources : They are confined to national boundries, e.g., minerals, lands.
(2) Multinational resources : They are shared by more than one country, e.g., some rivers, lakes, migratory animals.
(3) International resources : They are shared by all inhabitants of the earth, e.g., sunlight, air.
Conservation
It may be defined as the most efficient and most beneficial utilization of the natural resources. Conservation is also defined as the rational use of the environment to provide a high quality of living for the mankind.
Aim of conservation : The true aim of conservation, thus, includes.
(1) To insure the preservation of a quality environment that considers aesthetic, recreational as well as product needs.
(2) To insure a continuous yield of useful plants, animals and materials by establishing a balanced cycle of harvest and renewal.
Living resource conservation has three specific objectives
(1) To maintain the essential ecological processes and the life support system : This system has five elements (air, water, land, flora and fauna) which are interconnected, interrelated and interdependent; deterioration in one inevitably affects the other four elements.
(2) To preserve the biological diversity : It includes two related concepts genetic diversity and ecological diversity. The genetic diversity is the amount of the genetic variability among individuals of a single species (intraspecific genetic variability) as also between species (interspecific genetic variability). The ecological diversity means the species richness. It is the number of species of the flora and fauna found in a region (for example, India has about 45,000 species of plants and about 65,000 species of animals).
(3) To ensure that any utilization of the species and ecosystems is sustainable : In fact, natural resources may be conserved by efficient utilization which requires a proper balance between the supply and demand. Sustainable utilization means planned utilization so that a continuous yield of the useful plants, animals and materials may be obtained.
The conservation of the following resources is necessary
(1) Minerals : Minerals are largely nonrenewable inorganic resources that are presently mined from lithosphere. Availability/distribution is quite unequal Malayasia and Indonesia are rich in tin, tungsten and manganese but deficient in molybdenum. North America has abundant molybdenum but little tin, tungsten and manganese. South Africa has rich deposits of gold, platinum and uranium but little iron and silver. India has abundant iron, manganese, dolomite, chromite and mica but is deficient in lead, potassium, phosphorus, nickel, copper, silver and gold. Phosphate rocks have recently been discovered in Jawar Kota in Rajasthan. Mineral resources of scarce elements (e.g., silver, copper, mercury, tungsten) are liable to be exhausted within next 20-100 years. With continued use even plentiful minerals will become scarce and hence expensive, e.g., iron, aluminium.
(i) Degradation of environment : Every step of mineral extraction, processing, refinement and disposal causes degradation of environment.
(a) Mineral processing releases a number of pollutants into air. It also produces a number of wastes which bring about water and soil pollution.
(b) Mining not only damages the land, it also pollutes soil water and air.
(c) Mine dust destroys nearby vegetation and makes the soil barren. It is called mine spoil.
(ii) Conservation of minerals
(a) Reuse : An article can be reused several times, e.g., 16-17 times a glass bottle. Life of a machine/article can be prolonged with small care. However, all products cannot be reused.
(b) Low waste : Use and throw tendency should be checked where a durable and repairable article is concerned. Other points of wastage should be checked and wastage controlled.
(c) Manufacturing waste : It should not be thrown but reprocessed to be used in other industries.
(d) Substitution : Scarce metals which can be replaced by more abundant metals, e.g., copper in electric wires with aluminium, metallic pipes with plastic pipes. Plastics, ceramics and high strength glass fibres are being used in place of steel, tin and copper in many industries.
(e) Smaller articles : Smaller and sleeker articles should be made wherever feasible.
(f) Recycling : A number of metals can be recycled through reprocessing, e.g., gold, lead, nickel, steel, copper, aluminium, zinc. Recycling and reuse reduce pressure on mining and processing industries besides energy consumption and pollution. However, some minerals are lost during use, e.g., zinc, lead, chromium in paints.
(2) Forests : Forests are extensive self-sustained wooded tracts of land with abiotic community predominated by woody vegetation consisting of trees and shrubs with a close canopy. Woodland is closer to human habitation, possesses open canopy and is managed and maintained by human beings. Forests contain 90% of the terrestrial biomass. Forestry is branch of science which is connected with establishment, protection, management and exploitation of forests. Silviculture (= sylviculture) is a branch of forestry connected with cultivation and breeding of forest plants.
Table : 9.6-1 Forest cover in India
Class | Area (Sq.km) | % Geographic area | |
1. | Dense forests (> 40% canopy cover) | 3,77,358 | 11.5 |
2. | Open forests (10-40% canopy cover) | 2,55,064 | 7.8 |
3. | Mangrove (< 10% canopy cover) | 4,871 | 0.1 |
6,37,293 | 19.4 | ||
4. | Scrub (< 10% canopy cover) | 51,896 | 1.6 |
5. | Nonforest (Other Land Use) | 25,98,074 | 79.0 |
Total | 32,87,263 | 100% |
(i) Forest functions : Forests have three types of function :
(a) Productive functions (Economic Uses) : Forests provide a number of articles of economic use, e.g., wood, fruit, resins, alkaloids, essential oil, latex, pharmaceuticals.
(b) Regulative functions : They regulate global biogeochemical cycles, particularly carbon and water, check floods and drought by absorption, storage and release of water etc.
(c) Protective functions (Ecological functions) : They provide protection from excessive cold, excessive heat, drought, noise, radiations and smells besides providing shelter and conserving water and soil.
(ii) Economic uses
Wood consumption is estimated at 3-2 billion m3. 46% of wood is used in industry while 54% is consumed as fuel wood. Consumption of fuelwood is low in advanced countries (16%) while it is high in other countries (75-80%). Larger pieces of wood are used in timber. After timber, the major industrial consumer of wood is paper industry consumes the maximum amount of bamboo.
(iii) Ecological uses
(a) Protection of land : Plant cover protects soil from drastic changes in temperature, action of wind, action of rain drops, holding soil, preventing landslides and making the soil spongy as well as fertile.
(b) Climate : Moderating and moistening effects.
(c) Frequency of rainfall : Increases. Atmospheric humidity becomes high.
(d) Pollution : Forests reduce atmospheric pollution absorbing gases and collecting SPM.
(e) Shelter : To wild animals. Over 40 million tribals and villagers live in forests. The number of cattle grazing in forests is 200 million.
(iv) Retention of subsoil water : Plant litter and humus prevent run-off, hold water like a sponge and allow percolation resulting in perennial fresh water through springs.
(v) Deforestation : It is removal, decrease or deterioration of forest cover of an area. In 1900, forests occurred in 7000 million ha which were reduced to 2890 million ha in 1985 and about 2400 million ha in 2000. Tropical forests have come down from 1600 million ha to 938 million ha. In India, one third of the land was covered by forests in late nineteen thirties. In 1951 it was only 23%.
Causes : (a) Jhuming (b) Hydroelectric projects (c) Forest fires (d) Human establishments (e) Overgrazing (f) Requirement of wood (g) Quarrying and mining.
(vi) Effects
(a) Shrinking fuelwood : In Himalayas a woman spends half day on collecting fuel. In India, availability of fuel-wood is 58 million m3/yr against requirement of 300 million m3.
(b) Reduced timber : There is decreased availability of timber and other farm products.
(c) Change in climate : Deforestation results in reduced rainfall, increased drought, hotter summers and colder winters.
(d) Global warming : Deforestation increases atmospheric CO2 content by releasing carbon stored in organic matter and reduced primary productivity.
(e) Rainfall : Amount and periodicity of rainfall decreases. In drier areas deforestation, therefore, leads to desertification or formation of desert.
(f) Drought : There is very little water in rivers during dry season causing drought.
(g) Loss of biodiversity and germplasm etc.
(vii) Conservation and management of forests : Forests cover has to be increased to reverse the effect of past deforestation. For this sustained efforts are made for reforestation and afforestation. Tree plantation movement or Van Mahotsava is being carried out in India since 1950 where by both government and private agencies perform tree plantation during July and February every year. Conservation of forests aims at management of forests in such a way as to maintain them at optimum form and derive optimum sustainable benefit for present as well as future generations. Two major strategies are adopted.
(a) Production or Commercial forestry : It is plantation of useful trees and shrubs for meeting the commercial requirements without causing any undue demand on the natural forests. It is of three types – social forestry, agroforestry and production plantation.
(b) Protection or Conservation forestry :
- Degraded forests are mended through sylviculture practices. The forests are allowed to recoup before allowing its exploitation.
- Certain forests included under sanctuaries and national parks are not allowed to be exploited.
- Well stocked and mature forests are exploited scientifically.
- Prevention of scraping and Litter removal.
- Advanced silviculture.
- Fire fighting equipment.
- Economy in extraction and use of timber.
- Sustained yield block cutting : Cutting is allowed only in nonvulnerable forests at a rate which is equal to their regeneration capacity.
- Chipko movement : It is movement initially meant for protecting trees but now meant for preservation of environment including habitat and wildlife.
(viii) Other forms of forestry
(a) Social forestry (Started in 1976 by NCA) : Raising quick growing multipurpose plants in common village lands for meeting requirement of fodder, firewood and small timber.
(b) Urban forestry : It is plantation of fruit, flower and shade bearing plants in urban areas to reduce pollution and ultimate yield of wood.
(c) Production plantation : It is growing of industry required trees on specific, either fallow or free grazing lands. Production plantation decreases pressure on real forests.
(d) Reserve forests : They are forests grown over ecologically fragile areas where our water regimes are not located. Felling of trees and grazing are not allowed.
(e) Agroforestry : It is plantation of multipurpose trees/shrubs/horticulture plants/grasses alongwith crops for stabilising soil, meeting the need of fodder, fruit and timber of the community. It is of three types – agri-silvicultural, agri-pastoral and agri-silvi-pastoral.
(3) Grasslands (Rangeland) : They are biomes dominated by grasses and herbs (especially leguminous). Grasslands provide forage to cattle and support wildlife based on grazing food chain. Tall grasses are used in thatching and as fuel. Grasslands are quite stable because highly branched fibrous root systems hold the soil particles firmly and prevent soil erosion. They are, however, prone to invasion by trees and shrubs as well as desertification. The total area under grass cover is about 18% of total land in India. Therefore, the area available for grazing in India is roughly 37% (19% forested + 18% grassland).
(i) Grassland degradation : Grasslands have been put to three types of pressures.
(a) Overgrazing : At one time in the history of human civilisation, cattle were reared in large number. The number continues to be high. For example in arid and semiarid areas of India, the number of grazing animals is 2-10 times higher than their grasslands can support.
(b) Erosion : Overgrazing denudes the soil of plant cover. Trampling by cattle decreases soil porocity. The exposed hardened soil undergoes erosion by wind and water. Wind erosion is more common where drought conditions prevail for long periods. It causes desertification or conversion of once fertile land into desert.
(c) Conversion : Overpopulation and pressure to raise agriculture yield for feeding it. As a result several grasslands with fertile soils have been converted into agricultural lands, e.g., North American prairies. The pressure on remaining less fertile grasslands increases for feeding cattle.
(ii) Grassland management
(a) Grazing should be limited to only that number of animals which can be comfortably supported by a piece of grassland.
(b) Removal of tree seedlings, bushes, shrubs and weeds which tend to reduce productivity of grasslands.
(c) Occasional seeding with high yielding leguminous herbs for maintaining soil fertility.
(d) Grasslands should be closed to grazing when new plant growth is to take place, like rainy season.
(e) A grassland should be divided into blocks with each block be allowed to be grazed on rotational basis. This allows other blocks to recover.
(f) Reducing loss of soil and water from the grassland by contour bunding.
(g) Occasional controlled burning of dried mulch to promote release of nutrients and prevent growth of tree and shrubs.
(4) Soil erosion and Soil conservation : Top soil is the vital part of the soil and serves as the chief source of nutrition for plants (feeding zone). Loss or disturbance of top soil by natural agents like water, wind, gravity or ice is called soil erosion.
Soil erosion has been called ‘creeping death of the soil’ by Rama Rao.
Soil erosion is of two types :
- Geological or Natural erosion : It is caused by nature.
- Accelerated or Artificial erosion : It is caused by man and animals.
(i) Types of soil erosion
(a) Water erosion : It is caused by fast running water or by continuous heavy rain. It may be :
- Sheet erosion : Due to heavy rain, top fertile soil is removed in the form of thin sheet.
- Rill erosion : Fast running water cut stream or groove like structure in soil.
- Gully erosion : On steep slopes, fast running water cuts the soil deep and form channel like structure called gullies.
- Rparian erosion : During floods fast running water cut off the margins of river.
Due to heavy rains the minerals are also lost from top soil and soil becomes less fertile.
(b) Wind erosion : Soil erosion by wind is common in dry places and most servere in arid regions where soil is chiefly sandy and the vegetation is poor or even absent.
The wind throws away smallest soil particles into air where they get suspended giving a dusty appearance to the air. It is called suspension. By this method the soil particles are transported to longer distance.
(c) Land slide or Slip erosion : The hydraulic pressure caused by heavy rains and gravitational force cause the fall off the rocks in hilly areas.
(d) Overfelling (Deforestation) and Overgrazing erosion : These process reduce vegetation thus make the soil surface open for erosion (sheet erosion).
(ii) Soil conservation : Prevention of soil erosion is called as soil conservation.
Methods of soil conservation
(a) Strip copping : Crops are arranged in bands or strips to check the flow of water.
(b) Crop rotation : Crop rotation is the method of alternative sowing of leguminous and cereal crops (wheat , maize). The rotation of crops can be planned depending upon the climatic conditions, type, slope and properties of soils.
Such crops which check soil erosion should be sown during the rainy season. Legumes are useful in rotation of crops because of having nodulated roots. Soil fertility is usually maintained in the field by rotation of crops. The minerals which are consumed by cereal crop in first year are again supplied by leguminous crops in the second year.
(c) Reforestation or Afforestation : Growing of forest trees is most effective in controlling soil erosion. Afforestation also helps in prevention of floods. Indiscriminate felling of trees have resulted in the formation of extensive ravines along Yamuna and Chambal area. The Government of India has introduced the festival of ‘Van Mahotsava’. In this festival planting of trees is done on open waste land.
(d) Terracing : Hilly slopes are divided into small flat fields called as terraces to check the flow of water.
(e) Contour farming : It is the oldest method in low rain fall area. Field is divided in furrow and ridges. Ridges at same level called as contour.
(f) Green manuring : Basically its practice is meant for increasing soil fertility but it also checks soil erosion.
(g) Dry farming : A practice for cultivation of crops in low and moderate rainfall areas.
(h) Mulching : Basal plants parts are used to make a soil cover which help in moisture conservation.
(5) Water resources : Three fourth surface of earth (71% of total) is covered by oceans which contain 97.5% of total water. It is marine water with about 3.5% salt content. Only 2.5% water is fresh water which occurs on land. Most of this water (1.97%) occurs as frozen ice caps and glaciers. 0.5% water (fresh water) occurs as ground water. Rivers and lakes contain 0.02%, soil 0.01%, while atmosphere possesses 0.001% of water as vapours.
Fresh water is the major renewable resource in terrestrial habitats being essential component of all living beings, a habitat for several organisms, determinant of vegetation and climate, floods and droughts which also has a number of human uses.
(i) Problems related to water resources
(a) Nearly 40% of human population resides in arid and semi arid areas where most of time, energy and efforts are spent in procuring water for domestic and agriculture use.
(b) At most of the other places more water is withdrawn from surface and subsurface reservoirs than their recharging. As a result many wetlands have dried up. Ground water is becoming scanty at many places.
(c) Supply of fresh water to urban and industrial areas has always been a problem because of the huge amount involved. The average consumption of fresh water per person in modern society is 350-700 litres per day. Further, several industries consume large quantities of fresh water. The disposal of used water is still another problem. As a result there is a great amount of misuse and abuse of fresh water.
(d) Excessive irrigation in arid/semiarid areas increases soil salinity.
(e) Over-withdrawal of ground water in coastal regions results in movement of saline water from sea in underground aquifers, resulting in spoilage of water quality.
(f) Deforestation, especially in the hilly areas has reduced water absorption, storage in catchment areas, greater incidence of soil erosion and floods during rainy season. At other times the water supply is very little.
(ii) Conservation of water resources : A number of measures are required for optimum utilisation and conservation of fresh water resources.
(a) Rainwater harvesting : Surface storage and recharging of groundwater should be carried out.
(b) Afforestation : It helps in preventing soil erosion, reduces surface run off, retains water and protects water sheds for continued water supply.
(c) Industry : Wastage should be reduced. Waste water can be recycled.
(d) Domestic water supply : Wastage should be reduced. Waste water should be treated and used in irrigation and other purposes.
(e) Irrigation : Assured irrigation is available to only 40% area as compared to over 90% in advanced countries. There is a lot of wastage of agriculture water because only 50% of water supplied to soil is useful, the rest goes waste. Bricklining of irrigation channels and sprinkling technique of irrigation are recommended to save water.
(iii) Management of water resources
(a) Dams and Reservoirs : They can be constructed to control floods and ensure round the year supply of water besides generation of electricity.
(b) Desiltation : Dredging and desiltation of water bodies should be undertaken regularly to prevent decrease in capacity for storage.®
(c) Desalination : Sea water and saline underground water can be converted into fresh useful water through desalination.
(d) Canals : They are made to carry water in arid and semiarid area.
(6) Fisheries : Fishes are also one of the important biotic resources and are greatly valued by man as food. Unfortunately, in the last few year fish fauna of our inland waters has greatly deplected on account of overexploitation and pollution of natural waters due to sewage and industrial wastes. It is therefore, necessary that these colourful creatures of our aquatic environment should be preserved. Fishery managers have developed many techniques to improve fish habitats. Some are :
(a) Large, artificial fielding reefs in the offshore waters of the oceans and freshwater lakes to provide hiding places and additional food which attracts the fish.
(b) Spawning channels to replace vital spawning areas destroyed or no longer accessible.
(c) Fix toxicants to destroy undesirable fish populations and restore the balance in favour of the game or commercial fish.
(d) Weed control.
(e) Fertilization and artificial enrichment.
(f) Various in-stream devices to make pools, provide cover, wash out slit, etc.
(g) Aeration and recirculation of lakes and reservoirs.
? USA has abundance of molybdenum but deficient in Tin, Tungsten and Manganese. |
? India is rich in Fe, Mn, mica, dolomite and limestone but deficient in lead, gold, silver, copper, nickel, K and P. |
? The coal reserves of the world are higher than that of pertroleum. |
? Maximum output of zinc in India is from Rajasthan. |
? Agriculture consumes maximum water all over the world. |
? Social forestry programme is started in 1976. |
? Chipko movement was born in March 1973 in Gopeshwar in Chamoli when trees were not allowed to be cut by village Folk. The movement has two leaders Chandi Prasad Bhatt of Gopeshwar and Sunderal Bahuguna of Silyara in Tehri. |
? Van Mahotsav was started by K.M. Munshi in 1950. |
? Rich and St. Barbibaker is known as “tree saint in India”. |
? Soil erosion : In India, wind and water erosion deteriorate some 40,000 ha every year. It is 5-18% of global erosion. |
? Some Abbreviations
CAZRI : Central Arid Zone Research Institute (Jodhpur). CPCB : Central Pollution Control Board. IBP : International Biological Programme. IUCN : International Union for Conservation of Nature and Natural Resources. MAB : Man and Biosphere Programme. NEERI : National Environmental Engineering Research Institute. WWF : World Wild life Fund (World Wide Fund for Nature). UNEP : United Nations Environment Programme. CPHERI : Central Public Health Engineering Research Institute at Nagpur. |
Conservation of Natural Resources
- Which one of the following groups consists of non-renewable organic resources
(a) Air, sand and clay
(b) Coal, oil and natural gas
(c) Air, minerals and water
(d) Water, wood and natural pastures
- The energy produced by hydel-power plant is
(a) Renewable and polluting
(b) Non-renewable and polluting
(c) Renewable and non-polluting
(d) Non-renewable and non-polluting
- Non-polluting renewable type of energy is
(a) Wind (b) Solar
(c) Tidal (d) All the above
- Inexhaustible but limited source of energy is
(a) Products of lakes and ponds
(b) Products of oceans
(c) Nuclear fuels
(d) Fossil fuels
- A depleting source of energy is
(a) Water (b) Wind
(c) Sunlight (d) Fossil fuel
- Which of the following environmentalist is pioneer in resource conservation
(a) Odum (b) Tansley
(c) William Vogi (d) Reiter
- Soil erosion can be prevented by
[CPMT 1971, 75, 82, 93, 95, 2003; Pb. PMT 1999; BHU 2000]
(a) Overgrazing
(b) Removal of vegetation
(c) Afforestation
(d) Increasing birds population
- Silent valley of Kerala is preserved because [BHU 1981, 85]
(a) Has many rare species
(b) Many new plants
(c) New hybrids
(d) None of the above
- Which of the following is an anti–forest conservation activity
[DPMT 1982]
(a) Economy in lumbering
(b) Clear felling
(c) Preservation of fires
(d) Preservation of wild animals
- Which of the following is non-renewable resource
[DPMT 1982; CPMT 1994, 95]
(a) Forest (b) Coal deposit
(c) Water (d) Wild life
- ‘‘National Institute of Oceanography’’ is situated at
[DPMT 1986]
(a) Bombay (b) Panaji (Goa)
(c) Lucknow (d) Chennai
- Soil conservation is the process where
[CBSE PMT 1989, 93]
(a) Sterile soil is converted to fertile soil
(b) Soil is aerated
(c) Soil erosion is allowed
(d) Soil is protected against loss
- National Environmental Engineering Research Institute (NEERI) is situated at
[BHU 1989; KCET 1999; Kerala CET 2003]
(a) New Delhi (b) Nagpur
(c) Bhopal (d) Baroda
- Deforestation may reduce the chances of [CBSE PMT 1990]
(a) Rainfall (b) Frequent cyclones
(c) Erosion of surface soil (d) Frequent land slides
- Chipko movement is concerned with [JIPMER 1990]
(a) Plant conservation (b) Project Tiger
(c) Plant breeding (d) Animal breeding
- Sal forests are found in India [MP PMT 1990]
(a) In western ghats (b) Dehradoon valley
(c) Nilgiri hills (d) Satpura mountains
- Petroleum is a [CBSE PMT 1992]
(a) Non-renewable source (b) Renewable source
(c) A synthetic product (d) An inconvinient source
- Percentage of land covered by forests in India is [AMU 1992]
(a) 9-18% (b) 18-27%
(c) 27-36% (d) More than 50%
- Minerals and metals are [CBSE PMT 1992]
(a) Renewable resources
(b) Non-renewable resources
(c) Renewable and non-renewable resources
(d) Biodegradable resources
- Forests participate in [CPMT 1994]
(a) Controlling pollution
(b) Prevention of soil erosion
(c) Maintenance of ecological balance
(d) All the above
- Non-renewable source is [RPMT 1995]
(a) Water and gas
(b) Plant and coke
(c) Coke and mineral substances
(d) Energy and water
- Which of the following is a renewable resource
[Bihar MDAT 1995]
(a) Fossil fire (b) Metal
(c) Water (d) All the above
- Chipko Andolan (Movement) which was started in 1970 in Garhwal/Himalayas (Gopeshwar) near Alaknanda river was for the first time initiated by [AMU 1997]
(a) Chander Prasad Bhatt (b) Sunder Lal Bahuguna
(c) Baba Amte (d) Vinoba Bhave
- Deforestation leads to [AMU 1998; MHCET 2003]
(a) Soil erosion (b) Global warming
(c) Soil protection (d) Both (a) and (b)
- Land mass occupied by forest is about or According to Indian forest policy what percentage of the land area should be under forest cover [CBSE PMT 1999; AIEEE 2003]
(a) 11% (b) 22%
(c) 30% (d) 60%
- Forests should be conserved as they provide [Pb. PMT 2000]
(a) Food (b) Medicine
(c) Wood (d) All of these
- Afforestation with regard to urban development is called
[Pb. PMT 2000]
(a) Social forestry
(b) Integrated Forest Management
(c) Both (a) and (b)
(d) None of these
- Social forestry is useful in yielding [Pb. PMT 2003]
(a) Floriculture (b) Timber
(c) Medicines (d) Multipurpose uses
- In India highest amount of coal is present in [MP PMT 2003]
(a) West Bengal (b) Maharastra
(c) Jharkhand (d) Assam
- Which of the following is a non-renewable energy source
[HP PMT 2005]
(a) Hydropower (b) Tidal power
(c) Geothermal energy (d) Nuclear energy
- More than 70% of world’s freshwater is contained in
[CBSE PMT 2005]
(a) Polar ice (b) Glaciers and mountains
(c) Antartica (d) Greenland
- Mine spoil is
(a) Wastes from mines
(b) Wastes from mine processing
(c) Land degraded by mining
(d) Both (a) and (b)
- Conservation is [CPMT 1986]
(a) Protection of natural resources
(b) Management of natural resources
(c) Proper use of natural resources
(d) All the above
- Overgrazing causes [AIIMS 1985]
(a) Negative pollution
(b) Positive pollution
(c) Soil erosion
(d) Reduction in crop yield
- Forest control drought though [CPMT 1986]
(a) Lot of water plants
(b) Increasing rainfall
(c) Retention of water and prevention of erosion
(d) Functioning as water shed
- Deforestation brings about [DPMT 1984, 86]
(a) Increased sunlight (b) Increased grazing area
(c) Weed control (d) Soil erosion
- Silent Valley has been preserved as it has [BHU 1981]
(a) Recreational value
(b) Valuable timber plants
(c) Natural forest
(d) Rare plants and animals
- Chipko movement is connected with
[BHU 1994, JIPMER 1990, HPMT 1994, CPMT 1998]
(a) Conservation of natural resources
(b) Plant/forest conservation
(c) Plant breeding
(d) Project tiger
- Forests take part is [CPMT 1994]
(a) Control of atmospheric pollution
(b) Prevention of soil erosion
(c) Maintenance of natural balance
(d) All the above
- Afforestation should be with [Haryana PMT 1994]
(a) Exotic species (b) Indigenous species
(c) Bamboos (d) Eucalyptus
- American water plant that has become a troublesome water weed in India is
[MP PMT 1989; CBSE PMT 1993; AFMC 2000]
(a) Cyperus rotundus (b) Eichhornia crassipes
(c) Trapa latifolia (d) Trapa bispinosa
- Fertility of soil is measured by its ability to[CBSE PMT 1992]
(a) Retain nutrients (b) Hold organic materials
(c) Hold water (d) Support life
- Soil conservation is [CBSE PMT 1989]
(a) Conversion of sterile soil into fertile one
(b) Aeration of soil
(c) Erosion of soil
(d) Protection against loss
- Removal of top fertile soil by wind or water is
[CPMT 1980,84,85; JIPMER 1987, MP PMT 1988; BHU 1991]
(a) Siltation (b) Soil erosion
(c) Weathering of soil (d) Leaching
- Best source of renewable energy is
[DPMT 1984, MP PMT 1988,95]
(a) Cattle (b) Petroleum
(c) Coal (d) Trees
- Mulching is helpful in [BHU 1983]
(a) Increasing soil fertility
(b) Improvement of soil structure
(c) Moisture conservation
(d) Better crops
- Value of a resource is dependent on its [AIIMS 1989]
(a) Quality
(b) Quantity
(c) Requirement and type of society
(d) All the above
- Water is a resource [CBSE PMT 1992]
(a) Nondegradable nonmaintainable
(b) Degradable maintainable
(c) Renewable
(d) Non-renewable
- Largest amount of fresh water is found in [CBSE PMT 1994]
(a) Lakes and streams (b) Underground
(c) Polar ice and glaciers (d) Rivers
- Source of energy which does not evolve CO2 is
[RPMT 1995,96]
(a) Coal (b) Oil
(c) Organic compounds (d) Nuclear energy
- Fossil fuels have been formed by a [DPMT 1996]
(a) Conventional process
(b) Natural process
(c) Non-conventional process
(d) All the above
- In hilly areas, erosion is minimised by [BHU 1999]
(a) Terracing (b) Manuring
(c) Ploughing (d) Mixed cropping
- The important energy resource which originate from photosynthetic activity of green plants is
(a) Dendrothermal (b) Biogas
(c) Tidal energy (d) Both (a) and (b)
- Restoration of ecological equilibrium in mined areas can be achieved through [DPMT 1986]
(a) Revegetation of the mined habitats
(b) Conversion of mined habitats into agricultural ecosystems
(c) Prevention of soil erosion
(d) Prevention of grazing
- ‘Social forestry’ aims at [AIIMS 1996]
(a) Growing different types of plantations together
(b) Growing one type of trees on the land
(c) Management of forests by village bodies
(d) Management of forests by cooperative societies
- If we remove half of the forest cover of earth, the crisis that will occur [CBSE PMT 1996]
(a) Many species would become extinct
(b) Population, pollution and ecological imbalance will rise
(c) Energy crisis will commence
(d) The remaining forest will correct the imbalance
- Jhoom cultivation refers to [Pb. PMT 1998]
(a) Cultivation of Jamun trees
(b) Cultivation of medicinal plants by tribes
(c) Tribal method of shifting cultivation
(d) Cultivation of terraces
- Soil fertility can be maintained without addition of nutrients due to [BHU 1985]
(a) Floods
(b) Crop residue
(c) Activity of microorganisms
(d) Favourable temperature and water
- Geothermal energy is [DPMT 1986; Pb. PMT 1998]
(a) Nonrenewable nonconventional energy source
(b) Nonrenewable conventional energy source
(c) Renewable nonconventional energy source
(d) Renewable conventional energy source
- Greatest problem in water conservation is to reduce the amount of [BHU 1991]
(a) Ground water (b) Precipitation
(c) Run-off water (d) Evaporation
- Ecofriendly method is [CBSE PMT 1999]
(a) Plantation of C3 plants
(b) Plantation of sugarcane
(c) Energy plantation
(d) None of the above
Read the assertion and reason carefully to mark the correct option out of the options given below :
(a) If both the assertion and the reason are true and the reason is a correct explanation of the assertion
(b) If both the assertion and reason are true but the reason is not a correct explanation of the assertion
(c) If the assertion is true but the reason is false
(d) If both the assertion and reason are false
(e) If the assertion is false but reason is true
- Assertion : Present bioshpere is also called noosphere.
Reason : Man has mainpulated the environment according to his needs.
- Assertion : All resources are not exhaustible.
Reason : Renewable resources can become non-renewable.
- Assertion : Nuclear energy can be produced only by fusion of certain elements.
Reason : Nuclear reactions generate enormous energy.
- Assertion : Oceans are a source of edible plants and animals.
Reason : Oceans possess pure mineral nodules.
- Assertion : Litter burning is not suggested by ecologists.
Reason : Burning litter enchances CO2 content of the air.
- Assertion : Forests are renewable resource.
Reason : Conservation of forest has multifold benefits.
- Assertion : In India, 10% land are under irrigation.
Reason : India is rich in fresh water resources.
- Assertion : Coral reef is highly productive region.
Reason : It shows maximum diversity of biota.
- Assertion : Fossil fuels are important source of energy.
Reason : Fossil fuels provide energy to different industries.
- Assertion : “Chipko Andolan” was done by women of Reni village.
Reason : “Chipko Andolan” was done to protect wild life.
Conservation of Natural Resources
1 | b | 2 | c | 3 | d | 4 | d | 5 | d |
6 | c | 7 | c | 8 | a | 9 | b | 10 | b |
11 | b | 12 | d | 13 | b | 14 | a | 15 | a |
16 | b | 17 | a | 18 | b | 19 | c | 20 | d |
21 | c | 22 | c | 23 | b | 24 | d | 25 | c |
26 | d | 27 | b | 28 | d | 29 | a | 30 | d |
31 | a | 32 | c | 33 | d | 34 | a | 35 | c |
36 | d | 37 | c | 38 | b | 39 | d | 40 | b |
41 | b | 42 | d | 43 | d | 44 | b | 45 | d |
46 | c | 47 | c | 48 | b | 49 | c | 50 | d |
51 | c | 52 | a | 53 | d |
Critical Thinking Questions
1 | a | 2 | c | 3 | b | 4 | c | 5 | c |
6 | a | 7 | d | 8 | c |
Assertion and Reason
1 | a | 2 | b | 3 | e | 4 | b | 5 | c |
6 | b | 7 | e | 8 | a | 9 | a | 10 | c |
Conservation of Natural Resources
- (b) Non-renewable resources are those which cannot be again generated or produced e.g., fossil fuels (coal, petroleum products, lignite, natural gas), minerals, etc.
- (d) They all are non-conventional source of energy.
- (c) Afforestation means to cultivate the forest. The soil is hold by the roots of the forest plants and soil erosion can be prevented.
- (a) Silent valley is tropical evergreen forest in Kerala declared as National reserve forest because it contains very rare species of plants and animals.
- (d) Prevention of soil erosion is called as soil conservation.
- (a) Distruction of forest is called deforestation and in absence of plants water cycle gets disturbed.
- (a) Chipko movement is movement initially meant for protecting trees but now meant for preservation of environment including habitat and wildlife.
- (c) Due to very long recycling in case of metals and some mineral but shorter recycling in case of bioenergy nutrients.
- (c) Renewable resources are those which can be again generated or produced artificially or naturally e.g., forest, water, marine resources etc.
- (c) Until recently, forests covered one third of land surface.
- (d) Trees provide us food, clothes, wood (for fuel and furnitures) medicines, shelter for animals and helps in purifying our environment. So, it is very necessary to conserve forests.
- (a) Three fourth surface of earth is occupied by oceans which contain 97.5% of total water. This is marine water with about 3.5% salt contents. Rest water i.e., 2.5% is fresh water which occurs on land. Most amount of this water (about 1.97%) occurs as frozen ice caps and glaciers and 0.5% fresh water occurs as ground water.
- (c) Mine dust destroys nearby vegetation and make the soil barren. It is called mine spoil.
- (d) Excessive falling of trees and overgrazing remove the vegetation cover and then soil can be easily away by water and wind.
- (c) Silent valley of Kerala was saved through public agitation against setting up of hydroelectric project in natural forest area.
- (b) Chipko movement initially meant for protecting trees but now meant for preservation of environment including habitat and wildlife.
- (b) For afforestation native species should be preferred. Exotic species can be employed on only selective basis.
- (b) Loss of top fertile soil or disturbance in soil structure is called soil erosion.
- (c) Mulching is a covering of harvested field with plant litter or polyethene in order to decrease run off, prevent growth of weed and retention of water.
- (d) Nuclear reactor does not emit CO2 in atmosphere.
Critical Thinking Questions
- (c) Social forestry started in 1976 by NCA in which raising quick growing multipurpose plants in common village lands for meeting requirement of fodder, firewood and small timber.
- (b) Habitats of a large variety of organisms would be destroyed and food chains would be disturb leading to population and ecological imbalance.
- (c) Traditional system of agroforestry which allows regrowth of forests after clearing and cultivation in an areas for a few years is called Jhoom or Shifting cultivation.
Assertion and Reason
- (a) Man manipulates the environment to keep him in comfort and to feel secure. Each stage of evolution made man more powerful than other animals and increased his ability to manipulate the environment. These events changed to biosphere into a human dominated environment called noosphere.
- (b) Depending upon the abundance and availability, the natural resources are classified into two categories –inexhaustible and exhaustible. Examples of inexhaustible resources are air, clay and fungi. Excessive use of renewable sources makes them non-renewable, e.g., underground water, forests and wild life are renewable resources but can become non-renewable if they are not used properly and carefully.
- (e) Nuclear energy is obtained from fusion or fission of atoms of certain elements. Nuclear fusion involves the fusion of the nuclei of two atoms instead of the splitting of atoms that occurs in nuclear fission. Nuclear reaction consists of both fusion and fission of atom. The result is the release of enormous quantities of energy.
- (b) Oceans are a source of fish and other edible animals. A number of kelps (brown alage) and red sea weeds are edible. Oceans possess a number of nearly pure mineral concentrates in the form of nodules. The mineral nodules are a rich source of manganese, copper, nickel and cobalt. They occur in pacific ocean between Hawaii and Mexico as well as along our coast.
- (c) Soil fertility is restored by recovery of minerals from decomposition of fallen leaves, twigs, dead roots, dead animals and animal excreta. Litter burning contributes very less CO2 emission and is not responsible for increased CO2 content. But, litter burning deprives the soil from recovery of minerals.
- (b) Forests are renewable living resource which provide wood and a number of othe products. Conservation of forests is used in
(i) prevention of soil erosion.
(ii) Flood control.
(iii) Maintenance of water cycle.
(iv) Maintenance of health of climatic regimes.
(v) Perennial supply of water and
(vi) Providing raw materials timber, wood pulp and a number of other industries and for many other intangible benefits.
- (e) India has vast fresh water stretches in the form of rivers (27360 km), canals and irrigational channels (112650km) reservoirs, lakes, tanks, pools, ponds, etc. Today, India has the largest network of irrigation in the world. However, in actual terms, this is not enough. Only 18.7% of the land had assured irrigation, 24% is partly irrigated while 58% (above 42%) of the agricultural land is rain fed and without any irrigation.
- (a) A highly productive part of the coastal region is coral reef. It is formed of foraminiferans, calcareous algae and calcareous skeletons of coelenterates especially corals. Maximum diversity of biota occurs in the reefs.
- (a) The major energy sources are fossil fuels such as coal, petroleum and natural gases. They are an important source of energy for the modern technology. Fossil fuels are used in industry, thermal plants, agricultural operations, automobiles etc.
- (c) The popular Chipko andolan was started in 1973 in Gopeshwar, U.P. The villagers under the leadership of Chandi Prasad Bhatt pledged that they would not permit any more falling of trees. A group of woman of Reni village also stopped the contractor from cutting the trees by hugging the trees whenever they were tried to cut. Chipko andolan advocates the slogan of planting 5F’s – food, fodder, fuel, fibres and fertilizers trees to make communities self sufficient in all their basic needs.
- Terracing is an effective method of soil conservation in
[CPMT 1989, 90, 93, 2002]
(a) Desert areas (b) Hill areas
(c) Plain areas (d) None of the above
- Which communities are more vulnearble to invasion by outside plants and animals [CBSE PMT 1998]
(a) Tropical evergreen forests
(b) Temperate forests
(c) Mangroves
(d) Oceanic island communities
- Recurrence of floods in the plains of North India is due to excessive [BHU 1983, DPMT 1985]
(a) Siltation of dams
(b) Rainfall
(c) Agriculture
(d) Deforestation in catchment area
- Eroded soils are [CPMT 1989]
(a) Devoid of plant nutrients
(b) Richer in plant nutrients
(c) Unaltered in plant nutrients
(d) Fit for agriculture
- Soil conservation is achieved through [CPMT 1988]
(a) Restricted human activities
(b) Good plant cover
(c) Wind screen
(d) Ploughing
- Fuel wood crisis can be overcome by [APMEE 1999]
(a) Better wooden stoves
(b) Efficient wood extraction
(c) Greater afforestation
(d) Using alternate energy source
1 | b | 2 | d | 3 | d | 4 | a | 5 | b |
6 | d |
- (b) Terracing farming is a widely practicised in hilly area in which slope is divided into a number of flat fields for slowing down the flow of water.
- (a) When soil erosion occurs the top soil is removed and only the top soil is fertile as it contains organic matter and nutrients and productivity of land is reduced due to devoid of plant nutrients.
- (b) Because plant cover protects soil from drastic changes in temperature, action of wild, actin of rain drops, hold soil, preventing land slides and making the soil spongy as well as fertile.
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