Write down the Importance of soil? Give necessary suggestion to control the problem of desertification.

Importance of soil

Like rains, soil is also an important factor. Plants depend for their nutrient, water supply and anchorage upon the soil free floating, aquatic plants which derive their nutrients dissolved in water medium around them, soil is the chief storage of all the nutrients, which may available to the water medium. So soil system is indeed a complex and dynamic. Soil may affect plants by affecting seed germination, size and erectness of the plant, vigor of vegetative organs, woodiness of stem, depth of the root system, susceptibility to drought, frost and parasites, number of flower per plant and time of flowering.

Warning: (1909) has proposed five ecological groups of plants.
(1) Oxylophytes : found on acid soil.
(2) Halophtyes found on saline soil.
(3) Psammophytes found on sand.
(4) Lithophytes : found on rock surface.
(5) Chasmophytes : found in rock services.

Give necessary suggestion to control the problem of desertification.

Necessary suggestion to control the desertification:

(1) To control on animal pasture.
(2) Change in agriculture system.
(3) Spread human-conscious towards desertification.
(4) Right use of available water resources.
(5) Plantings in desert area.
(6) Ban on tree cutting.
(7) To ban unmanagable stone mines.
(8) To apply to desert develop programme.
(9) To make available other resources for fuel.
(10) Planting on hill area and other open area.
(11) To tell the local people about the famine and importance of trees.

Discuss the ways in which Land is degraded. Suggest steps to check Land Degradation.

Apart from pollution, land and soil face many other problems. These are deforestation, erosion, flooding, water logging, salination, desertification and urbanization. If degradation of soil and land continues at current rates, about one third of the farmland may be destroyed by the end of the century.

1. Soil erosion : Removal of top fertile layer of the soil by water, wind, oceanic waves and glaciers is called soil erosion. Erosion of soil by water generally occur near hills, where high speed rivulets and flooding removes top soil. India experience floods almost every year due to destruction of forests in catchment areas of rivers. Strong winds also erode the soil and bring sand from deserts to adjacent fertile land, converting the latter into desert. Thar Desert in Rajasthan once a fertile land has been formed by shifting of sand from Gujarat Coast.

Erosion occurs in both wet and arid regions, irrespective of whether it is traditional or modernized agriculture. Various human activities such as felling of trees, over-grazing, over cropping and improper tilling accelerate soil erosion. The roots of grasses keep the soil intact. Disruption of the grass cover by plough loosens the soil and makes it vulnerable to erosion. Tilling or grazing on slopes or semi-arid soils increases the rate of soil erosion.

Soil erosion is world-wide phenomenon but it is especially high in Nepal, India, China, Australia, Spain, USSR, USA and Central Africa. Over 40,000 hectares of land are affected by wind and water erosion in India every year.- The damage of top soil in India is 18.5 percent, which is the maximum of the global loss. It is due to over-grazing of live-stocks whose population is largest in India.

2. Shifting cultivation: It is a peculiar practice of slash and burn agriculture prevalent in many tribal communities inhabiting in tropical and sub-tropical regions of Asia, Africa and Oceania (Islands of Pacific Ocean and nearby sea), It consists of cutting down trees and setting them on fire and raising crops on the resulting ash. This practice is called Jhuming in north-eastern India and is spread in 3 x 10 Km2 of tropical or Jhum forests. It is not harmful, if the Jhuming cycles are longer. However, when Jhuming is done in 5 to 10 years of cycle, destroy forests and destabilises the soil

3.Desertification:  Transformation of fertile and into a desert by natural or man’s activities is called desertification. It can result from various causes such as erosion of top soil, shifting of sand dunes by wind and overcrazing in lands sparsely covered by grass. Many deserts of the world have developed by the aforesaid human activities.

4. Developmental activities : Various developmental activities such as rapid urbanization, construction of dams, roads, railways, airports, Industries and mining have caused excessive loss of large areas of fertile and productive croplands, woodlands and grasslands.

Control of Land Degradation

 The following measures can be adopted to check the land degradation:

(1) Land degradation by soil erosion, floods and water logging can be checked by restoring forests and grass covers.

(2) Degradation of soil by shifting cultivation can be prevented by crop rotation, mixed cropping and plantation cropping. These practices would Improve soil fertility.

(3) Salinity of soil can be checked by improving drainage, salinated lands can be reclaimed by leaching them with more water, if the ground water table is not high.

(4) Advancement of deserts can be checked by mulching (use of artificial protective covering) or by growing appropriate plant species and by raising trees as wind breaks.

Describe the Land Resources?

Land Resources

Land is a major constituent of one of the life supporting system, the lithosphere. It is an important source of many materials essential to man and other organisms.

Area : Land forms about one fifth of the earth’s surface covering about 13,393 million hectares. About 36.6 percent of the land area is occupied by human dwellings, factories, roads, railways, deserts, mountains, rocks and polar ice marshes. About 30 percent of the total land mass is under forests. About 22 percent of land is occupied by meadows and pastures. Only 11 percent land is suitable for ploughing.

Soil : The fertile surface layer of earth capable, of supporting plant is called soil. Terrestrial plants obtain their water and mineral nutrients in the soil. Plants and animal materials decay and are released into the nutrient bank in the soil. Many micro-organisms and animals involved in detritus path way inhabit the soil. Soil covers about four fifth of the land area. The study of soil is called pedology (Gk pedion= ground, logos = discourse). It deals with the origin, formation and geographic distribution of soil.

Soil is formed by two processes (i) weathering : breaking down of rock into small particles and ii) pedogenesis : maturation of soil through development of humus. Weathering of rocks involves physical and chemical breakdown. Physical breakdown is caused by temperature variations, alternate ,drying and wetting, microbial activity, action of plant roots and burrowing animals. Chemical breakdown occurs by oxidation, reduction, hydration Ind other related reactions.

Composition of Soil : Soil is composed of five constituents: (i) mineral matter (ii) organic matter (iii) soil water (iv) soil air and (v) living organisms.

  1. Mineral matter : It is derived from the underlying parent rock by weathering and occurs in the soil as particles. The mineral particles are regular in outline and therefore enclose spaces called interstices for circulation of air and water.; Depending upon their size the mineral particles f soil are of following types
    Gravel 2.00-5.00 mm
    Coarse Sand 0.20-2.00 nun
    Fine Sand 0.02-0.20 mm
    Silt 0.002-0.02 mm
    Clay Less than 0.002 mm
    Sand and silt consist largely of quartz (Si02) and are chemically inert. Clay particles are chemically active. They enclose smaller but more numerous spaces, which can hold water but little air.

Soil Texture : The physical structure of a soil is called soil texture. It upon the percentage of its mineral particles. Soil texture determines the porosity and nutritional status of the soil. There are three important textural soil types — sandy, clayey and loamy.

  • Sandy soils: They contain less than 10 percent each of clay and The remaining part is sand They are porous and well aerated. They, however, have little water holding capacity and are chemically inert. Sandy soils are generally called light soils because of the absence of moisture and crumbs formation. They are, therefore, unfit for plant growth.

(ii) Clayey Soils : They contain about 40 percent or more clay. They I are called heavy soils because the soils are compactly packed with little aeration. They have small sized pores, which retain water very firmly, little aeration. They have small sized pores, which retain Water very firmly. Clayey soils are rich in nutrients but do not support good plant growth due to poor aeration.

(iii) Loamy soils: They contain sand, silt and clay approximately in the ratio of 2 : 2 : l. They are ideally suited for plant growth because they possess good aeration, sufficient nutritive salts and good water retaining capacity.

Soil Crumbs : Soil crumbs are large, soft and spongy soil pieces, which have honey comb structure with high porosity. The functional structure of the soil is dependent upon the formation of soil crumbs. Soil crumbs are produced by the cementing of soil particles with the help of clay particles and gums present in the humus. Soil crumbs can hold both water and air besides containing nutrients.

2. Organic Matter : It is derived from plant refuse (leaves, twigs, roots), dead bodies of organisms and their excreta. The organic matter is broken down by microbes and is converted into dark amorphous substance called humus. Humus is very useful substance in the soil. It performs following functions:
(i) It acts as sponge and absorbs rain water and also increase water holding capacity.
(ii) It makes a soil porous and increases aeration of the soil.
(iii) It provides various minerals such as phosphorus, sulphur, calcium and potassium to the soil.
(iv) It contains several acids, which assist in weathering of rocks, cause solubilization of heavy mineral salts and functions as buffer against pH changes.
(v) Gums present in the humus act as binding agent.

3. Soil water: The soil particles are occupied by the water or air. The water in the soil is present as capillary water, hygroscopic water, combined water and water vapour. Small spaces serve as capillaries and allow the water to move against the pull of gravity. It is called capillary water. Some water form an extremely thin film around the soil particles and is called hydroscopic water. A small portion of soil water is chemically bound with soil materials called combined water. Some water vapour is also present in the pore spaces. Plants can draw only capillary water from the soil. It is called available water. If soil water is not replenished from time to time, a stage is reached, when the plants growing in it become permanently wilted. The amount of water in percentage left in the soil at the time of permanent wilting of the plants is called permanent wilting percentage (PWP) or permanent wilting coefficient (PWC). At this stage soil contains about 10 percent of water. This water is called non-available water and is held in the soil as hygroscopic water, combined water and water vapours.
Soil receives water either by rains or irrigation. Excess of water entering soil percolate down to permanent water table through larger pore spaces. It is called gravitation water. The maximum amount of water retained per unit dryweight of soil after the stoppage of gravitational flow is called water sliding capacity or field capacity of the soil. It is 25-35 percent in loam soil. Soil moisture beyond field capacity causes water logging. It is harmful to plants as it drives away soil air

4. Soil air: Soil contains air in the pour spaces. In a good soil such as about 20-25 percent of the total volume is soil air. The composition of is dependent upon ventilation or connection of the pore spaces with the surface. In a poorly ventilated soil, concentration of oxygen decreases while that of carbon dioxide increases because of the respiration of plant sand soil organisms. High concentration of carbon dioxide in the soil is to the soil organisms. Oxygen in soil is essential for humus formation, respiration of microorganisms and activities of roots (absorption and mineral salts). Lack of sufficient aeration reduce nitrates and s of the soil to form free nitrogen and toxic sulphides in the soil.

5. Soil organisms : A variety of living organisms occur in the soil include bacteria, actinomycetes, fungi, algae, protozoa, nematodes, worms and burrowing animals. The soil organisms perform following activities in the soil:
(i) Saprophytic soil microorganisms decompose the dead organic matter release the nutrients in the soil for their reuse by the plants.
(ii) A number of bacteria and cyanobacteria present in the soil, fix atmospheric nitrogen into the soil.
(iii) Burrowing animals increase aeration of the soil and also bring nutrient rich sub-soil to the surface.
(iv) Several soil organisms secrete mucus, which help in cementing soil particles to form soil aggregates.

The salt content, pH and organic and inorganic nutrients like nitrogen phosphorous and potassium determine its chemical properties. The topography, climate and biotic factors control the condition of the soil.

Depletion of Land Resources : A number of factors a:e posing danger to land resources and are causing depletion to the productive land. They include : (i) soil erosion due to wind or water (ii) salination due to improper irrigation and faulty drainage system (iii) acidification due to leaching of soluble bases (iv) deposition of salt due to floods and (v) developmental activities such as construction of dams, road, railway urban encroachment, industrialization and mining.

Describe the mineral resources and explain the conservation of minerals?

Mineral Resources

There has been a steady increase in the consumption and global demand of minerals. Annual rise in the use of steel making minerals is 3-5 percent, of fertilizer production material is 3 percent, of phosphate rock 5.2 percent, and of aluminum 43 percent. The demand of non-fuel mineral will further by the development of less developed countries.

Most of the minerals reach sedimentary layers of the oceans and their takes a very long time. So these minerals remain out of the mineral cycles. Minerals are exhaustible non-renewable resources. Their limited stock earth once exhausted cannot be replenished. There is danger of depletion all known and easily available deposits of minerals within a few decades.
Moreover, geographical distribution of mineral deposits is not uniform. It is likely that some countries may monopolise deposits of certain essential minerals.

However, the crisis can be met by adopting measures such as:

(i) Development of technology for efficient extraction of minerals from ores.

(ii) Exploitation of untapped deposits.

(iii) Obtaining sedimentary minerals by deep sea mining.

(iv) Judicious use of minerals.

(v) Finding new uses for plastics, glass, ceramics and synthetic fibers.

(vi) Sharing of advancement in the field of mining, extraction and use substitute substances in place of exhaustible minerals.

(vii) Designing small equipments, pumps and engines with high efficiency.

Minerals include all materials derived from the earth by mining. Such materials may be of organic origin like coal or petroleum or inorganic in origin. Inorganic substances include both metallic and non-metallic materials. Minerals are dug out from the earth either from the surface or at varying depths.

Though minerals occur widely in rocks, they can be mined economically only at places where their concentration is high. A rock in which a particular metallic mineral occurs in a concentrated form is called an ore. Therefore, mining is limited to sites where ores occur. Though iron and aluminum may be found in most of the rocks, they are mined in those localities where they occur as ores.

Many metallic minerals like gold, silver, lead and zinc occur as ores in the form of narrow lodes or veins in igneous or metamorphic rocks. Coal and lignite occur as seams of layers between sedimentary rocks. Petroleum and natural gas occur in the pore space in sedimentary rocks. Some minerals like tin, gold and diamonds occur in gravel, sand and other alluvial deposits on the river beds. Denudation of rocks in the upper reaches of river basin has removed them from their original sites. They have been transported by rivers and deposited in the lower reaches. Such deposits are called placer deposits.

The occurrence of rich mineral deposit in an area may remain unexploited if physical and economic conditions are unfavourable. For example, mineral deposits in Tropical forests or deserts remain unexploited due to harsh living conditions.

Generally high grade are located near urban centers or ports are the first to be minded. When they get exhausted or mining conditions become difficult, distant deposits are opened up or imports are made from other countries. When prices increase, it becomes economical to mine low grade ores also. Price increase also boosts exploration and discovery of new deposits even in areas which were considered unfavourable. Continuous exploration of new resources is necessary to ensure supply of minerals as old mines get exhausted in a few years. Mineral ores contain a number of substances along with the mineral.

The percentage of mineral occurring in the ore varies from place to place. Minerals have to be processed to remove impurities and obtain pure mineral. Processing of iron ore to obtain iron involves establishment of a large manufacturing unit at great cost. Petroleum cannot be used in its crude form. It has be refined into petrol, diesel oil, kerosene etc.

IRON: India is exceptionally rich in both quantity and quality of its iron ore deposits. The ores mainly consist of hematite and magnetite.

The iron content of the ore is as high as 60 to 70 percent. This explains the big international demand for our iron ore. The official estimates of the proven reserves are 17,570 million tonnes. These estimates are on the Conservative side. Half of these deposits are confined to the districts of Singhbhum in Bihar and adjoining districts of Keonjhar Bonai and Mayurbhanj in Orissa. It is perhaps the world’s largest and richest iron ore field. Iron ore is also mined in Hazaribagh and Sbahabad districts of Bihar.

Bihar-Orissa iron fields further extend into Raipur, Durg and Bastar  in Madhya Pradesh. The mines in Bailadila in Bastar have been lately developed to step up exports to countries like Japan. Madhya Pradesh ranks now next only to Bihar and Orissa in mining iron ore.
The iron ore deposits are also found in several districts of Andhra Pradesh. The State of Goa has also iron ore deposits, although of not very high quality. They are largely exported. Ratnagiri and Chanda districts of Maharashtra have some iron ore deposits. The production of iron ore has been steadily rising. Unfortunately major portion is mined for export rather than manufacture of iron and steel in our own country. The ports specializing in the export of iron are Visakhpatnam (for Bailadila mines). Manna Goa, Paradip and Calcutta, Manglore is likely to emerge as an iron ore exporting port, as Kundremukh mines have been developed for this purpose.

Manganese

Ferro alloys are mixed metals with iron as the base are prized for their strength, and as such they have become very Important in the age of powerful giant machines. Manganese is used for this purpose and hence its growing importance.

The mines of manganese are located in Mayurganj and Keonjhar in e State of Orissa. In karnantaka, the deposits are located in Chitredurga, lumukur, Shimoga, Chikmaglur, Belgaum, Dharwar and North Kanara districts.

The other States in which manganese is found are Bihar (Singhbhum), Andhra Pradesh Pradesh (Nizamabad and Visakthapatnam) and in Rajasthan (Banswara Udaipur). The total production in 1987 was 13 million tonnes as against the Dnservative estimates of 135 million tonnes of total reserves. Of these at least 50 million tonnes are of high quality.

Bauxite: Bauxite ore has gained an importance because aluminum: a very light but highly useful metal, is produced from it. It is a must for aircraft industry. It is also now being increasingly used in electrical industry rand also in everyday life. But the manufacture of alumina and aluminium depends largely on the availability of cheap and abundant supply of electricity.

The bauxite deposits in India are widely distributed. Traditionally Bihar, Gujrat and Madhya Pradesh have been the major producers. Maharashtra has also high grade deposits in Koihapur district. Recently deposits in Orissa have been developed and the largest plant of its kind in Asia has been set up to produce aluminia and aluminium. It annual capacity is 800,000 tonnes of alumina and 225,000 tonnes of aluminium. It uses the latest French technology which economizes on the use of electricity. Ore is exported to Japan and European countries.

In 1987 the output of bauxite was 2.6 million tonnes. The country’s reserves are estimated at 270 million tonnes, of which 73 million tonnes are of high quality.

Mica: India produces nearly 90 percent of the world’s mica. It is a basic ingredient of the electrical industry. India accounts for two-thirds of the world’s mica entering into international trade. Annual production is about 30,000 tonnes. Half of it comes from Hazaribagh, Gaya and Munger districts of Bihar. These districts lie on the northern edge of Chotanagpur plateau. The remaining half is equally shared by Nellore district in Andhra Pradesh and Bhilwara District in Rajasthan. India faces competition from Brazil. It has been noticed that our way of mining mica are rather wasteful.

Copper : Copper was widely used for making household utensils. In fact before the discovery of iron, copper held its way symbolizing march of civilization. But today it is valued as the best conductor of electricity. Currently, most of the ore is mined in the districts of Singhbhum (Bihar), Balaghat (M.P.) and Jhunjhuni and Alwar (Rajasthan). The minor producers are Khamman district of Andhra Pradesh, Chitradurga and Hassan district of Karnataka and also Sikkim. The total reserves are estimated at about 570 million tonnes with only 6.3 million of copper content. The annual output of the ore in 1987 was nearly 5 million tonnes.

Gold : India is very poorly placed in regard to the reserves of gold ore. Currently, gold is mined at Kolar mines, the world’s deepest, and Hutti mines (Raichur District), both in Karnataka. The other two mines in Anantpur and Chiltoor districts of Andhra Pradesh have lately started functioning. The known reserves are placed at only 81,000kg of gold content.

Conservation of Minerals : The limited stock of minerals on once exhausted cannot be replenished. Therefore, consumption of minerals needs immediate attention. Following measures can be adopted to conserve the mineral resources—

  1. The wasteful and injudicious consumption of minerals should be checked by recycling and devising more efficient techniques.
  2. Untapped mineral deposits should be exploited. Deep sea mining can yield more minerals.
  3. Designing smaller equipments, using some alternative new raw material can also minimise the excessive use of minerals.
  4. Using proper substitutes of minerals and finding more uses of glass, plastic, synthetic fibres and ceramics.

Describe the Water Resources? Also write a note on conservation of water resources ?

Water Resources : Water is the ii in constituent of hydrosphere. It is renewable resource and covers four-fifths of the earth surface.

Distribution : Water is present all around us, as vapour in the air even In dry deserts It is present under our feet in the soil. There is some 1.4 billion cubic kilometer (km) of water in the hydrosphere. Of this about 97 percent is ocean water, which is unsuitable for human use. Only 3 percent is available as fresh water. About 77.2 percent of the fresh water is locked in
Ice caps and glaciers and 22.4 percent is ground water and soil moisture. The remaining about 0.36 percent is distributed in rivers, lakes, streams and swamps.

Types : Water resources of two types : fresh water resources and Ocean or marine water resources.

Fresh Water Resources

Fresh water resource is essential for life on land and survival of human race. Fresh water is exhaustible, but it is renewed by oceans through “hdrological cycles. About 90 percent of water evaporating from the oceans turns to the latter and the remaining 10 percent fall on the land surface to port natural and man-made ecosystems. Fresh water occurs in ponds, ;, streams, rivers and underground pools. India receives about 2.75
million cubic kilometers of fresh water through an average rainfall of about 110 cm per year. Out of it 0.6 million cubic kilometer seeps into ground, while rest flows into rivers. The ground water reserves of India is about 27 million cubic kilometer or ten times of annual rainfall.

Human Uses : Man obtains fresh water from rivers, lakes, ponds and und. The fresh water is used for following purposes.

(1) It is used for drinking, cooking, bathing and washing.
(2) It is used for disposal of human excreta through sewers.
(3) It used in industries and for construction works.
(4) Water falls and river currents are used to generate electricity.
(5) It is used for raising fish and aquaculture i.e. raising of useful aquatic plants. India with about 1.6 million hectares of inland water has a vast potential for aquaculture. Inland fisheries provides about 40 percent of the total fish production in the country.
(6) Water is also used for navigation and recreational activities like swimming, boating and yatching.

Water Problem A rapid rise in population and expansion in industry and agriculture have increased the demand for water manifold. The average per capita consumption of water in modern society is 350 to 700 liters per day. The demand for usable water.is increasing rapidly. It is becoming difficult to cope with the rising demand for water. Certain factors also confront with the limited resources of usable water and add to the problem. The most important of these are given below.
(1) Deforestation in the catchment areas in the recent past has greatly reduced the absorption of rain water. This has led to soil erosion and wastage of water by way of floods.
(2) Misuse and abuse of fresh water in many residential houses and industries. The disposal of waste or used water is still another problem.
(3) Large scale burning of fossil fuels make the rain water acidic and make the same unfit for use.
(4) Water seeping through soil dissolves a large number of salts and becomes hard. Hardness of water shortens the life of utensils, water heaters, boilers and turbines. Water containing salts more than 3.5 gm per liter is not fit for irrigation.

Conservation of Water : Though water renews itself through hydrological cycles, still an increasing demand for water needs its conservation. Following measures can be adopted for this purpose:
(1) Treatment of used water before passing it into irrigational channels or rivers.
(2) Prevention of wastage of water in irrigation through brick lining of channels and subsurface and sprinkler techniques.
(3) Prevention of water wastage in industries and homes.
(4) Prevention of water pollution by not all allowing raw swage and industrial effluents to pass into water bodies.
(5) Building of dams up streams to store flood water for use during dry periods.
(6) Afforestation and reforestation of hill slopes and catchment areas to hold water and prevent its loss through floods.
(7) Building of tanks and ponds to retain rain water for later use in areas, where perennial sources of water are not available.

 Ocean or Marine Resources

The ocean resources are of two types, biotic and abiotic. The abiotic type of ocean resources are used for the following purposes:

(1) Common salt is prepared from sea water by concentration in salt pans in coastal areas.

(2) Sea water and Ocean bed are rich in many minerals. Sodium Chlorine, bromine and magnesium are extracted from the sea. A number of nearly pure mineral concentrates in the form of nodules occur in sea bed.
These 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.

(3) Ocean tides are used to generate electricity.

(4) Oceans provide extensive surface for navigation.

(5) Oceans serve heat banks for coastal regions by absorbing and heat.

What is a flood and explain causes of flood?

Flood simply means inundation of extensive land area with water for several days in continuation. Generally, floods are considered to be associated with rivers and people conceive flood as the outcome of accumulation of huge volume of water coming out of the rivers through overtopping of river banks during peak discharge period. In fact, flood is an attribute of physical environment and thus is a component of hydrological cycle of a drainage basin. It may be pointed out that flood is a natural phenomenon and is a response to rainfall but it becomes hazard when it causes colossal loss to human lives and property. It is also important to note that floods are also aggravated by human activity and thus flood hazard is both natural as well as man-induced rather man-accentuated phenomenon. Floods are very often associated with rivers draining extensive alluvial and flood plains About 3.5 percent of the total geographical area of the word is covered by flood plains which house about 16.5 percent of the total population of the world. The most notorious rivers of the world in terms of devastating floods and resultant damage to natural environment (riparian decay) and loss of human lives and property are the Ganga and its major tributaries such as the Yamuna, the Ramganga, the Gomti, the Ghanghra., the GaiJak, the Kosi, the Damodar etc. (northern India), the Brahmaputra (north-east India), the deltaic segments of the Mahandi, the Krishna, the Godawari, the Tapi, the Narmada, the Lum, the Mali etc. (all in India), the Mississippi and Missouri (U.S.A.) the Yangtze, the Yello (China), the Irrawadi (Myanmar) the Indus (Pakistan), the Niger (Nigeria), the po (Italy), the Euphratus and Trigris (Iraq) etc.

Causes of Floods

Since the floods of rivers are the responses of both natural and anthropogenic factors, the cause of flood of the alluvial rivers become highly complex and their relative importance varies from place to place. Among the natural factors which cause river floods Important are prolonged high intensity rainfall; meandering courses of the rivers; extensive flood plains; break in slope in the long profiles of the rivers. i.e. sudden change in channel gradient at the intervening zones of the foothill slope of the mountains and upper end of the plains; blocking of free flow of the rivers because of enormous debris provided by landslides and due to volcanic eruptions; nature of river valleys and channels etc. Anthropogenic activities such as building activity and eventual urbanizaion, channel manipulation through diversion of its (of the river) course, construction of bridges, barrages and reservoirs, agricultural practices, deforestation, land use changes etc. by man invite several hazards in the river system viz, disastrous floods, landslides and slumping along the banks, massive erosion along the river banks causing large-scale riparian decay. Shifting of channels and even of the river courses, siliting of beds. deposition of sands, silts and clays in the flood plains etc. which pose a serious threat to human society and necessitate river regulation and flood control (Savindra Singh, 1983). The following causes may be held responsible for devastating floods of alluvial rivers. They may be held responsible for devastating floods of alluvial rivers. It may be pointed out that these factors should never be considered separately because it is the cumulative effects of several factors which ultimately cause severe floods.

Explain the terms: (a) Deforestation (Forest Destruction) (b) Afforestation (c) National Forest Policy.

(a) Deforestation (Forest Destruction) : Deforestation is a threat to the economy, quality of life and future of the environment. Main causes of deforestation in India are explosion of human and livestock population, increased requirement of timber and fuel wood, expansion of cropland and enhanced grazing. Another cause of forest degradation is construction of roads along the mountains. Increased demand for fuel wood, wooden crates, paper, board and newsprint have led to large scale tree felling. Ideally one third (or 33%) of land of a country must be covered by forest. In India, forest cover is only 19.43% out of which only 13% are thick forest. Rest is bushy land. Deforestation has caused intensified soil erosion, accentuated floods and drought and loss of precious wild life and has led to deterioration of economy and quality of life of two weaker sections of the society.

India is losing about 1.5 million hectares of forest cover each year. Nearly one percent of the land surface of India is turning barren every year due to deforestation. In the Himalayan range, the rainfall has declined 3 to 4 percent due to deforestation.

(b) Afforestation : Forests occupy central position in nature. They restore ecological balance of all ecosystems, maintain biological diversity, art as catchments for soil and water conservation, prevent floods and safeguard future of tribal people. In order to meet such needs, we need to develop massive afforestation programme of indigenous and exotic fast growing species for production and protection of forestry on suitable land including wasteland. A massive social forestry programme is needed to meet demands of local people for fuel, fodder, timber, etc. Then there is need for wood-based industry.

Today the two major goals for forestry are

(i) Supply of goods and services to people and industry by a well thought out plan of production, and long term ecological security through conservation of forest cover and its restoration.

(ii) Conservation of forest or Reserve forests, i.e., National Parks, sanctuaries, sacred groves, biosphere reserves and all ecologically fragile areas are covered by Government of India. No commercial exploitation can be allowed in these areas.

Limited production forestry : In these forests, the annual increment may be harvested in a very careful and controlled manner so as to avoid soil and tree damage. These forest are present in hilly areas at the height of more than 1000 meters.

Production forests : These are forests of plains. Their scientific exploitation does not pose any threat to environment.

Intensive plantation: This includes planting of all the available land from village fields, to community land and to road/rail sides and available space. Social and agro-forestry programmes are included in this category.

Production plantations : This is entirely commercial forestry developed to meet the need of the forest—based industry. Plantations are to be done on fallow land not being used for agriculture, mostly free grazing lands. Short rotation species are to be preferred over long duration sal and teak.

Social and Agro forestry : The social forest programme stared in 1976. It seeks the use of public and common land to produce firewood., fodder and small timber for the use of the rural community to relieve pressure on existing forests needed for soil and water conservation.

The programme includes raising, planting and protecting trees with multiple uses (firewood, fodder, agricultural implements, fruits, etc.) for the rural community.

The Agro-forestry Programme consists of reviving an ancient land use practice where the same land is used for farming, forestry and animal husbandry.

(c) The National Forest Policy, 1988 : The National forest Policy, 1988, stressed peoples involvement as one of the essential components of forest management in the development and protection of forests. The main features of the 1988 Forest Policy are : (i) maintenance of environmental stability through preservation and restoration of ecological balance; (ii) conservation of natural heritage; (iii) check soil erosion and denudation of catchment areas of rivers, lakes and reservoirs; (iv) check on extension of desert areas; (v) substantial increase in forest density through afforestation; (vi) steps to meet requirements of fuelwood, fodder, minor forest products and timber for rural and tribal populations, (viii) encouragement of efficient utilization of forest produce and optimum substitution of fodder and fuel wood, and (ix) steps to promote peoples participation in forest conservation.

Bio-diversity action plan. An ongoing national programme is attempting to reach out to tens of thousands of people in the making of a new vision and strategy related to environment and development. This is the National Bio-diverstiy Strategy and Action Plan (NBSAP).

There have been several international treaties and pacts relating to it, the latest and most comprehensive being the convention of Biological Diversity. The CBD was signed at the Earth Summit in Rio de Janeiro in 1992 by 155 nation states and came into force in 1993. This legally binding treaty obliges ratifying countries to protect bio-diversity to move towards the sustainable use of biological resources and to ensure that benefits from such use are shared equitably across local, regional, national and global societies. India ratified this convention m 1994.

National Bio-diversity Strategy and Action Plan (NBSAP) has also been launched in January 2000 by the Ministry of Environment and Forests.
It is an attempt towards truly operationalising the much abused word in the development sector called ‘participation’. To achieve this there has been an effort to decentralize the entire process. The NBSAP entails the preparation of action plans at five levels.

About 20 substate sites ranging from a village like Nahin Kalan in Uttaranchal to a protected area like the Simplipal Tiger Reserve in Orissa to the Bio-diversity rich West Garo Hills in Meghalaya.

• All 13 states an union territories of India
• 10 interstate ecoregions, cutting across state
• A National themes
• A National Strategy and Plan building on all of the above.

 Explain about Chipko Andolan and different forestery programmes ?

Chipko Andolan

The beginning of the revolutionary step as movement for conservation of forest began in 1972 at Tihari Garhwal in Uttar Pradesh (now in Uttaranchal) which is called Chipko Andolan (movement). The inspirer of Chipko. Andolan was Sunder Lal Bahuguna. When thc forests were cut down indiscriminately at Garhwal then women of Garhwal district decided that one woman should cling to one tree if some one tries to cut it. As such, when labourers came with axe to cut trees, they did not dare to cut the trees.

Such first public revolution had started much early in 1971 at Khejarli village in Marwar (Jodhpur). The then Maharaja of Jodhpur had ordered to cut down trees for fuel wood. Against this a resolution started under the leadership of courageous and fearless lady Amrita Devi. 363 members of Vishnoi caste clung to Khejdi trees. All of them were cut down along with the wood of the trees. This event sparked the movement for conservation of trees and forests.

The main aims of Chipko Andolan were as follows:
(1) To plant trees of environmental importance more in comparison to trees of business importance.
(2) To develop social and agricultural forestry
(3) To oppose the construction of big dams to keep a balance in ecosystem.
(4) To grow fruit bearing plants for economic importance.

Forestry Programmes

(A) Social Forestry Programme: This programme was started in 1976. To preserve the land and water in present time to save the forest in this programme, the grass, fuel and other bushes are planting by villages. In this programme multi-purpose trees plant and do its preservation.

(B) Agro Forestry Programme: Its objective was to alive the ancient agricultural system. It was told to the farmers that in fertile land, how they can keep continue the planting and husbandary in same land.

(C) Urban Forestry Programme: The objective of this programme was to plant the flower trees for beauty in town and cities. As such trees may be plant in public parks, both side of roads and on personal land.

Discuss the national forest policy of development programme of India?

National Forest Policy: During the early years of the British rule, when conditions were unsettled, Reckless destruction of forests went on unchecked. The East India Co. was more interested n immediate gains than in a long-term benefits to the country. With the transfer of authority in 1857 from the East India Co. to the British Crown, however, there was a welcome change of emphasis from immediate gains to long term benefits. The rapidly shrinking supplies of timber and fire-wood and the extensive soil erosion which followed deforestation compelled the Government to pay some attention to the urgent need for the preservation of forest wealth. Therefore, a forest policy had to be evolved. The first Inspector General of Forests was appointed in 1863 and in 1894 a Resolution on forest policy was issued. This Resolution said that: (i) forests should be managed to promote general well being of the country (ii) they should be maintained for the preservation of climatic and physical conditions of the country and (iii) to supply and fulfill the needs of the people for fuel and industries. This policy related to state forests in British provinces and forests were divided into : (a) forests, the preservation of which was essential on climatic or physical grounds; (b) forests that afforded a supply of valuable timber for commercial purposes; (c) minor forest: and (d) pasture lands.

Under the Indian Forest Act of 1927, three categories of forests were recognized- Reserved forests (the most strictly controlled). Protected forests (less strictly controlled), and Unclassed forests (which include ‘village forests’ or land classed as ‘culturable waste’).

Since the first systematic Forest Policy was declared, changes of far reaching importance had taken place in the economic field. Most important of these were:

(i) A substantial increase in human and bovine population which led to a heavier pressure on forest demanding more land for agriculture and pastures.
(ii) A heavy dependence on forest resources during the two world wars which led to rapid depletion of these resources.
(iii) Independent India launched reconstruction schemes such as the river projects, agricultural colonization schemes, development of forest based industries, and laying down of new railway lines all leaned very heavily on the forest products, and lastly.
(iv) Forest began to be regarded as the foster mother and not as the hand-maid of  agriculture.

Forest Development Programmes

For soil and water conservation and satisfaction of the present and prospective demand of the people for fuel wood and of the industries for industrial woods and other raw materials forest development has been regarded as a sine quo non for economic progress of the country. With this aim in view, the improvement of the existing forests received attention in the Five-Year Plans. The first two Plans put considerable emphasis on their consolidation, improvement of degraded forests, establishment of economic plantations of fast growing trees and improvement of communications.

Vana Mahaotsava was inaugurated in 1950 to create an enthusiasm in the popular mind for the preservation of forests and planting of new trees, as “trees means water, water means bread and bread is life. ‘ It was also hoped that it would create tree-consciousness among the people. The planting of trees during Vanmahotsava was to serve the following purposes:

(i) To provide fuel and thus release cow dung for use as manure.
(ii) To increase production of fruits and add to the potential food resources of the country;
(iii) To help creation of shelter-belts around agricultural fields, to increase their productivity;
(iv) To provide fodder leaves for cattle to relieve intensity of grazing over reserved forests.

The Third Plan emphasized the protective as well as the productive role of forests in the Indian economy and suggested a long term objective that a third of the land area should be under forests.

The Fourth Plan envisaged a high increase in the demand for various forest products both for industrial and for fuel purposes. During the Fourth plan in the sector of forestry three main objectives were to be achieved (a) to increase the productivity of forests (b) to link up forests development with various forests-based industries; and (c) to develop forests as a support to rural economy. Intensive exploitation and rational utilization of existing forest resources was aimed at.

The primary objective of the Draft Fifth Plan is: (i) To initiate measures for increasing production of Industrial wood and other forest products by a change over from conservation oriented forestry to a dynamic programme of production forestry, aiming at clear felling and creating large man made forests with the help of institutional fmancing. The produce from clear felled areas is to be used in wood-based industries by locating additional units wherever required; (ii) To develop farm forestry and improvements of degraded forests to increase the fuel and timber supply in the rural areas, (iii) To assess the present growing stocks, increments and potential increments by forest divisions, natural regions and timber slates, along with a proper information system on the forest working plans and working schemes.

During the Sixth Plan Period the Forest Conservation Act 1980 was enacted with the main objective of checking the diversion of forest land for non-forestry purposes.

The rule and importance of forests in the general economic development of the country in terms of protection of the ecosystem and supply of various forest products is better understood now the task bringing one third of the geographical area of the country under tree cover becomes a vital need and all possible efforts have to made to achieve this target by the end of this century.

Establishment of National Wasteland Development Boards, reconstitution of the Indian Council of Forestry Research and Education and application of remote sensing in forestry management are the new thrust areas for the Seventh Year Plan regarding the development of forest wealth in the country and to develop the research and education.

Explain the main causes of low productivity of forests?

The main causes of low productivity of forests are:

(i) Large area of unclassed State forests and the former private forests, acquired by the Government after the abolition of zamindari, are undermocked and required to be rehabilitated. The difficulty in organizing the Commercial exploitation of these products arise from their erratic distribution. Some products like Ephedra, Ratanjot and Kuth occur at high elevations. Myrobolans are usually dispersed over extensive areas rendering the cost of collection prohibitive. Herbs suffer from the same handicap.

(ii) Customary forest rights and concessions granted to the tribals and forest people for free grazing of their cattle in the forests and removing Umber, fuel and manure and minor forest produce have been very liberally exercised by them for a long time and this has led to the reduction of forest yield.

(iv) The large animal population reduces the possibility of efficient forest management, preservation and expansion through afforestation.

(v) Some of the forests (about 43 percent) have not yet been opened up sufficiently and therefore, only the most valuable trees can be extracted economically, others go to waste. Besides very few types in Indian forests are gregarious to enable their economical exploitation.

(vi) An appreciable proportion of trees are malformed or consist of species which are slow growing and poor yielders.

(vii) Antiquated transport and lack of proper bridle paths-rope ways and the road system in the forest areas are other bottlenecks in the full utilization of resources.

(viii) The methods of felling, fashioning and slow means of transportation entail much wastage and the costs are also high.

(ix) Large quantities of inferior woods which could be put to economic use through seasoning and preservation treatment remain only partially utilized.

(x) These are no commercial forests and most of the forests are meant for protective purposes. Reserved forests represent 48 percent : Protected forests 32 percent and unclassified forests are forests in name only.

(xi) The yield from forests is low because static conservancy (or natural growth of forests) is even now practised. This has its importance when scientific management had just begun. But now it is not suitable.

(xii) There are over one million hectares of over-aged inaccessible forests in H.P. and UP. in remote areas which are deteriorating and await immediate exploitation. The stands in these forest areas are good and valuable, they need good management practices.

(xiii) Many species of wood possess such defects as excessive sharpness, heaviness, twisted grains, brittleness, presence of oils or abrasive materials, poor seasoning ability and impregnation qualities which have rendered them economically useless.

(xiv) Lastly, inadequate protection against fire, plant diseases, insects, lack of complete information regarding timber supplies and other forest resources, inadequate research facilities and insufficiency of trained personnel are other factors which militate against full production.