The Dangers of Land Degradation Essay

The Dangers of Land Degradation Essay.

Soil is one of the most important natural resources of man. Soils are essential for man for growing crops, fodder and limber. Once the fertile portion of the earth’s surface is lost, it is very difficult to replace it. In India, the destruction of the top-soil has already reached an alarming proportion.

Land degradation problems have resulted in increasing depletion of the productivity of the basic land stock through nutrient deficiencies. In addition to the direct loss of crop producing capacity, soil erosion increases the destructiveness of floods and decreases the storage capacity of water in reservoirs.

It is therefore essential that the soils should not be allowed to wash or blow-away more rapidly than they can be regenerated, their fertility should not be exhausted and their physical structure should remain suited to continued production of desired plant materials.

Protection of land from further degradation, adoption of various conservation measures, including reclamation and scientific management of available land stock is very important for a country like India to achieve higher productivity of food, fodder, fuel and industrial raw materials on a substantial basis.

Besides, demand for land for providing social priorities such as shelter, roads, industrial activities is increasing at a very fast rate with the rise in population and very often good agricultural and forest lands are being diverted to such use.

It is, therefore, necessary to keep soil in place and in a state favourable to its highest productive capacity.

Soil Erosion

The process of destruction of soil and the removal of the destroyed soil material constitute soil erosion. According to Dr. Bennett “the vastly accelerated process of soil removal brought about by the human interference, with the normal disequilibrium between soil building and soil removal is designated as soil erosion”.

Types of Soil-Erosion

Erosion of soil by water is quite significant and takes place chiefly in two ways (a) Sheet erosion, (b) Gully erosion.

(a) Sheet movement of water causes sheet erosion and depends on the velocity and quantity of pronounced surface runoff and the erodability of the soil itself. In such cases, the soil is eroded as layers from the hill slopes, sometimes slowly and insidiously and sometimes more rapidly. Sheet erosion is more or less universal on:-

– all bare follow land,

– all uncultivated land whose plant cover has been thinned out by over grazing, fire or other misuse, and

-all sloping cultivated fields and on sloping forest, scrub jungles where natural porosity of soil has been removed by heavy grazing, felling of trees or burning etc.

The particles loosened and shifted by the rain drops are carried down slope by a very thin sheet of water which moves along the surface. The impacts of the raindrops increases the turbulance and transporting capacity of this unchannelized sheetwash which results in the uniform skimming of the top soil.

Sheet erosion is considered as dangerous as it may continue for years but may or may not leave any trace of the damage. Sheet erosion is common in the Himalayan foothills, in Assam, Western ghats and Eastern ghats.

When sheet erosion continues unchecked, the silt laden run-off forms well-defined minute finger shaped grooves over the entire field. Such thin channeling is known as ‘rill-erosion’, which is active over wide areas in Bihar, Uttar Pradesh, Madhva Pradesh and in semiarid areas of Maharashtra, Karnataka, Andhra Pradesh and Tamil Nadu.

(b) Gully erosion

On a gentle slope, adequately covered by vegetation, clay soil will resist erosion to a great extent and the water forms small rivulets which can then erode deeper. The rivulets in turn join together to form larger channels until gullies are formed gradually deep gullies cut into the soil and then spread and grow until all the soil is removal from the sloping ground.

This phenomenon once started and if not checked, goes on extending and ultimately the whole land is converted into a bad-land topography. Gully erosion is more common in areas where the river system has cut down into elevated plateaus so that feeders and branches carve out an intricate pattern of gullies.

Apart from this, it also takes place in relatively level country whenever large blocks of cultivation give rise to concentration of field run-off.

Wind Erosion

It occurs in dry climatic areas having a sparse and low vegetation cover on mechanically weathered, loosened surficial material. Dust storms are the principal agents of wind erosion.

The top soil is often blown off from the surface rendering it infertile. Besides, with the decrease in the wind velocity coarse sand particles get deposited in some areas covering the existing soil and rendering it unproductive.

The removal of soil by running water and wind is known as soil erosion. The soil-forming process and the erosional process of running water and wind are continuous. Generally, there is a balance between these two processes.

The rate of removal of fine particles from the surface is the same as the rate of addition of particles to the soil layer. Sometimes such a balance is disturbed by natural or human factors, leading to a greater rate of removal of soil. When this happens, the entire soil layer may be removed in a few years.

Types of Soil Erosion: Wind and water are powerful agents of soil erosion because of their ability to remove soil and transport it.

(a) Erosion by Water: Erosion by water can be of several types, for example, sheet erosion, gully erosion, stream bank erosion, shore erosion and slip erosion.

1. Sheet Erosion: When a layer of the soil on the surface is removed over a large area by running water, it is called sheet erosion. Sheet erosion is harmful since it removes the finer and more fertile top soil.

2. Rill Erosion: This is the second stage of sheet erosion. Small finger-like rills begin to appear on the landscape. Over a period of time, the fine rills increase in number and also become deeper and wider. This reduces the actual area under cultivation and the yield of crops decline.

3. Gully Erosion: When soil is removed by water flowing along definite paths downs the slope or in channels, it is called gully erosion. Gullies cut up agricultural land and make it unfit for cultivation. Badland is a region with a large number of deep gullies or ravines, e.g., Chambal Valley in Madhya Pradesh.

4. Stream Bank Erosion: The continuously flowing water erodes the banks of streams and rivers. Gradually the bed of the river widens.

5. Shore Erosion: The tidal waves dash against coastal rocks, causing them to erode bit by bit.

6. Slip Erosion: During heavy rains, water percolates into the soil until it is unable to penetrate further by the underlying impervious rocks. On steep land, the heavy moisture-laden soil often comes down bodily, resulting in a landslide.

(b) Wind Erosion is significant in desert and semi-desert regions. In regions with heavy rainfall and steep slopes, erosion by running water is more significant.

In some regions, the top soil is blown away by wind in the dry season, and washed away by running water in the wet season.

Causes of Soil Erosion in India: Soil erosion takes place when soil is removed faster than it is formed. There are many different processes by which soil is removed but the cause is usually the removal of trees and other vegetation that hold the soil together and in place.

1. Topography and Slope of the Land: Hilly Region: Rainfall occurs in torrents and washes away the top layer of the soil. Also, the steep slopes stimulate the eroding power of the rainwater.

Plains: Here the erosion is comparatively less than on slopes. But in regions where the rivers overflow onto the plains, the erosion is severe. For example, the entire basin of the Kosi River is threatened by the over-flowing of river.

2. Nature of Rainfall: Floods and torrential rains cause more damage than light or moderate showers spread over many days.

i. The action of heavy rain is stronger when there are no trees and the plains are bare.

ii. When a prolonged dry spell is followed by sudden heavy rain, sheet erosion takes place. This is because the ground gets baked hard and the soil is unable to absorb the water easily.

3. Nature of Soil: Porous soils with good water-absorbing capacity are least subject to erosion, while the impervious soils are gradually eroded by the action of water.

4. The Human Factor: Man and his activities are responsible for soil erosion to a great extent. As the human population increases, the demand on the land also increases. Forest and other natural vegetation are removed for human settlement, for cultivation, for grazing animals and for various other needs. Improper use of land leads to soil erosion.

The Dangers of Land Degradation Essay

Soil conservation Essay

Soil conservation Essay.

Soil conservation includes all such measures which protect the soil from erosion and restore its fertility. These measures are of two types-(a) small measures to check soil erosion at local or even individual level, and (b) large measures at govern­ment level involving larger area and heavy invest ment.

(a) Small Measures-These include afforesta­tion, regularised land strip cultivation or contour farming or terrace farming in hilly areas, use of stubble mulch system, increasing cohesiveness of the soils through artificial manures and fertilisers, gully plugging, restricting over grazing and shifting cultivation, erecting shelter belts and wind breaks to check wind velocity and wind erosion in arid and semi-arid areas, Fixing of sand dunes by planting trees and grasses, practicing alternate cultivation technique, popularising dry farming and adopting scientific crop rotation system.

(b) Large Measures-these include large projects and schemes undertaken by state and cen­tral government to check soil erosion and facilitate extensive reclamation. Following are some of the schemes worthy of mention here:

(i) Reclamation of Ravines and Badlands-

Massive large scale schemes are necessary for soil reclamation in ravines and badlands of Madhya Pradesh, Uttar Pradesh, Gujarat and Rajasthan.

Sev­eral such schemes involving plugging of gully mouths, construction of bunds across the gullies, leveling of surface, a forestation, and restriction on over grazing are under implementation in these states. In Madhya Pradesh the World Bank has given an assistance of Rs. 300 million to reclaim about 1 lakh ha of ravine land.

(ii) Control of Floods-In India the problem of soil erosion is very much linked with the problem of floods and waterlogging. This is due to seasonal and heavy downpour of rainfall. If arrangement could be made for the storage and diversion of additional rain-water not only it would be an effective measure to control the floods but to utilise this water in drier yet to see the light of the day due to paucity of funds.

(iii) Afforestation-Afforestation is another effective measure to check the erosion of soil either through running water or through winds. Such trees can be planted along the roads, canals, river banks, bordering areas of the desert and in ravine and wasteland areas. A forestation programmes may be undertaken at local and community level and also on regional and national level.

Along with a forestation equally important is the restriction on the indiscrimi­nate cutting of trees. People’s awareness in the form of Chipko movement and use of cheap substitute for fuel wood and wood products may be effective steps in this direction.

(iv) Restoration of Long Fallows-the country has 95.5 lakh ha. of old fallows of which about 80 ( lakh ha lie in 8 states, namely, Andhra Pradesh, Karnataka, Madhya Pradesh, Maharashtra, Rajasthan, Tamil Nadu, Bihar and Uttar Pradesh.

In 1982-83 a programme for restoration of long fallows was j launched in these 8 states which was later on ex­tended to 5 more states (Assam, Gujarat, Meghalaya, Orissa and West Bengal). On the basis of progress, reports about 9.66 lakh ha of fallows in these states were restored for productive purposes.

(v) Shifting Cultivation-a scheme to control shifting cultivation has been launched in seven north­eastern states of the country. This is a beneficiary oriented programme which aims at rehabilitating Jhumia tribal families with one hectare of terraced agricultural land and one hectare of horticulture and plantation crops.

The 8th Five Year Plan had an outlay of Rs 45 crore for the purpose. There is a need to extend this programme to other states of the country and gradually replace this old system by sedentary farming.

(vi) Reclamation of Alkaline (Usar) Soils- This is a centrally sponsored scheme launched in the states of Haryana, Punjab and Uttar Pradesh during the Seventh Five Year Pan. It has now been extended to the states of Gujarat, Madhya Pradesh and Rajasthan. The major components of the scheme include assured irrigation water, on farm develop­ment works like land leveling, deep sloughing, community drainage system, application of soil amendments, organic manures, etc. It is a 50: 50 funding between the Centre and the concerned states on identified components. Since the inception of the scheme an area of 4.32 lakh ha. Has been reclaimed with central assistance of Rs. 59.67 crore up to 1995- 96. There is a need to launch this scheme in other states of the country to combat the problems of salinity and alkalinity.

Soil Conservation through the Plans

Soil conservation programmes are taken in the context of national plan strategy to make the country self-reliant in food and other land based produces as well as to generate additional employ­ment opportunities in the extensive rural areas.

The characteristic features of the programmes include : (a) implementing field measures such as terracing, contour farming, intercropping, etc., for controlling run off and erosion, (b) raising wind breaks, shelter belts to check wind erosion, protecting crops from hot fast wind and fixing sand dunes, (c) land devel­opment and shaping, (d) a forestation and raising of utility trees, and (e) putting up erosion control-cum- water harvesting structures with a view to restoring degraded lands, create micro-level irrigation poten­tial and closures with working of soil conservation measures for development of grass-land (India 1985, p. 289).

The Central Government formed a Central Soil Conservation Board in 1953 to co-ordinate soil conservation programmes on all-India basis.

The Board implemented soil conservation programmes over 2.5 lakh hectares of area during the First Five Year Plan which increased to 8 lakh hectares during the Second Plan and 44 lakh hectares during the Third Plan. During Fourth Plan soil conservation programmes were redesigned to be implemented on watershed basis and 21 catchments covering 71 lakh hectares of area were selected. Fifth Plan had an allocation of Rs. 161 crores to reclaim 10 lakh hectares of area in catchment of major rivers and ravine lands as a result of which the total area treated under soil conservation programmes rose to 23.4 million hectares.Sixth Plan aimed at bringing addi­tional 7.1 million hectares of area under soil conser­vation programmes.

It also included centrally spon­sored scheme of integrated water-shed management in the catchments of 8 flood prone rivers of the Ganga basin. The Seventh Plan fixed a total outlay of Rs. 740.39 crore to put emphasis on preventing soil erosion and increasing soil productivity. Till 1995- 96 a total area of 39.3 million hectares in the catch- 212 of River Valley Prjccts has been treated under soil conservation programmes. One centre has been set up at Hazaribag under D.V.C. to impart training for soil conservation schemes.

The World Bank assisted projects, namely Himalayan watershed management project in Uttar Pradesh and pilot project for watershed develop­ment in the rainfed areas in Andhra Pradesh, Karnataka, Madhya Pradesh and Maharashtra are being monitored through Watershed Development Council (WDC) in the Department of Agriculture and Co-operation.

The All-India Soil and Land Use Survey Organisation has carried out works of delineation and codification of catchments into watersheds, fixa­tion of inter-set priorities of watersheds, determina­tion of hydrologic soil groups, infiltration character­istics, potential and problems of various identified soil series etc.

It is busy in carrying out reconnaissance, sample and detailed soil surveys of different parts of the country and has also identified 3772 watersheds for immediate planning. States have been asked to set up State Land Use. Boards for formulating, imple­menting and co-coordinating soil conservation programmes. A two-tier body, namely, the National Land Resources Conservation and Development Commission and the National Land Board has been set up to co-ordinate and oversee the activities of all the State Land Use Boards.

Besides Soil Conservation training Centre of Hazaribag (DVC), eight regional research-cum dem­onstration centres have been established at Dehradun (Himalayan region), Chandigarh (Siwalik region), Kota (ravines of Rajasthan), Valsad (ravines of Gujarat), Agra (ravines of Yamuna), Bellary (black soil), Ootacamund (hilly areas), Chhatra (watershed of Losi) and Jodhpur (desert for the study of prob­lems of soil and water conservation. Soil conservation is a set of management strategies for prevention of soil being eroded from the Earth’s surface or becoming chemically altered by overuse, acidification, salinization or other chemical soil contamination. It is a component of environmental soil science.

Erosion barriers on disturbed slope, Marin County, California Decisions regarding appropriate crop rotation, cover crops, and planted windbreaks are central to the ability of surface soils to retain their integrity, both with respect to erosive forces and chemical change from nutrient depletion. Crop rotation is simply the conventional alternation of crops on a given field, so that nutrient depletion is avoided from repetitive chemical uptake/deposition of single crop growth. Perimeter runoff control[edit] Trees, shrubs and ground-covers are effective perimeter treatment for soil erosion prevention, by insuring any surface flows are impeded. A special form of this perimeter or inter-row treatment is the use of a “grass way” that both channels and dissipates runoff through surface friction, impeding surface runoff, and encouraging infiltration of the slowed surface water.[2] Windbreaks[edit]

Windbreaks are created by planting sufficiently dense rows of trees at the windward exposure of an agricultural field subject to wind erosion.[3] Evergreen species are preferred to achieve year-round protection; however, as long as foliage is present in the seasons of bare soil surfaces, the effect of deciduous trees may also be adequate. Soil Conservation Measures in India – Essay

Soil and Water Conservation measures are one of the essential inputs for increasing agricultural output in the country. These programmes were first launched during the First Plan. From the very beginning, emphasis has been on development of technology for problem identification, enactment of appropriate legislation and constitution of policy coordination bodies. While conceptual framework of soil and water conservation activities has been changed, concept of programmes has undergone considerable revision during successive Five Year Plans. The Centrally-sponsored Scheme of Soil Conservation in the catchments of River Valley Project (RVP) was started in third Five Year Plan. Subsequently another scheme of Flood- Prone Rivers (FPR) was started in the Sixth Five Year Plan keeping in view the magnitude of floods in the year 1978.

Now, both schemes have been clubbed together during Ninth Five Year Plan on recommendation of Expenditure Finance Committee and further subsumed under Macro Management Mode since November 2000. Under the programme for the catchment management of River Valley Projects and Flood Prone Rivers, 53 catchments are covered, spread over 27 States. The total catchment area is 96.14 m.ha. With Priority Area needing urgent treatment in 26 m. ha. Out of this 5.69 m.ha. Have been treated till 2002-03 with an expenditure of Rs 1635.8 crores. A Centrally-sponsored Scheme of reclamation of alkali soil was taken up in Punjab, Haryana and Uttar Pradesh during the Seventh Five Year Plan. The scheme was further extended to the States of Gujarat, Madhya Pradesh and Rajasthan during the Eighth Five Year Plan.

During Ninth Plan extension of the scheme to all other States of India was approved where alkali soil problems exist as per scientific parameter. The scheme aims at improving physical conditions and productivity status of alkali soils for restoring optimum crop production. The major components of the scheme include, assured irrigation water on farm development works like land levelling, bunding and ploughing, community drainage system, application of soil amendment organic manures, etc. An area of 0.60 m.ha. Out of 3.5 m.ha. Of alkali land has been reclaimed till the end of 2002-03 in the country. The scheme at present stands subsumed in Macro Management Scheme. Another project for alkali land reclamation and development has been taken up in U.P. and Bihar with the help of EEC at an estimated cost of Rs 85.80 crore out of which Government of India’s share is Rs 6.88 crore.

The project envisages reclaiming 15,000 hectares of alkali soils during its life span of seven years. An area of 30,825 ha. Has been redaimed till the end of 2000-01 (terminal year). The scheme of Watershed Development Project in Shifting Cultivation Areas (WDPSCA) was launched in seven north-eastern States during the Eighth Plan from 1994-95 with 100 per cent Central assistance to the State Plan. The scheme aims at overall development of jhum areas on watershed basis. During Eighth Plan an amount of Rs 40.826 crore was released to the States -of north-east region and 0.67 lakh ha. Area was treated through treatment packages.

During Ninth Plan up to March 2002, 1.5 lakh ha. Have been treated with an expenditure of Rs 82 crore (against the approved programme and unspent balance of Eighth Plan). The new guidelines of the scheme on the basis of new watershed to common approach has been effective from November 2000 in the revised cost norms of Rs 10,000 per ha. On net treatable area basis with additional activities and improved institutional mechanism. During Tenth Plan, an area of 0.2 lakh ha has been treated at an expenditure of Rs 20 crore up to 2002-2003.

You may also be interested in the following: soil neutralizer, soil conservation essay

Soil conservation Essay