Tuesday, April 21, 2009

Need for soil conservation


— KC Patar Ecological balance plays a crucial role in sustaining various forms of life on earth. Various living organisms like plants, animals and microorganisms are continuously interacting with one another and also with soil, air and water. There is a continuous input of energy from the sun. All these components form a self-sustaining or functional ambit of the natural world. They are interdependent on each other. Life on earth is part of this interdependent system. Man derived it’s existence from this interdependent system. Therefore man cannot live apart from this natural world. From scientific and technological developments man has derived immense benefeits, but at the same time, it is also responsible for various types of environmental degradations.

From ancient time all the components of environment such as soil, tree, water, air, river, mountain and animal etc, have been considered as sacred in one form or the other. Therefore, protection of these components, has been of paramount importance and it was a part of religious activity. In the remote past, there was no environmental problem because of limited population and of simple pattern of life. Generally during present century with the growth of population, industrialisation and urbanisation as well as other economic activities environmental problems have emerged. Once soil is lost or damaged, the entire ecosystem is disturbed and this leads to interruption of nutrient cycle, loss of soil fertility, extinction of flora and fauna and soil erosion etc resulting in biological impoverishment and human sufferings.

If the soil of a region is fertile, it helps agriculture and industries of the region. It is found that the regions having fertile soil are thickly populated and have been the centres of civilisation and culture even in ancient period. For example the Ganga plain, the Delta region, the Damodar Valley and the Coastal regions of Bay of Bengal are agriculturally and industrially developed due to fertile soil. Soil is a resource for which there is no substitute. We may enhance the soil by helping it’s processes along, but can never recreate what we have already destroyed. Soil is of vital importance so far as existence of life is concerned. Soil formation is extremely slow process. Top soil is a valuable resource. To build one inch of top soil it normally requires 50 years or more depending upon the climate and soil type. Thus if the top soil erodes faster than it is formed, the soil becomes a non-renewable resource.

All life forms, including man,are utterly dependent upon a thin, nutrient and moisture rich mantle of soil. Soil is therefore of vital importance for existence of many forms of life that have evolved on our planet earth. Soil itself is a much more complex phenomenon than most people realise. Soil is a natural covering on the earth’s land surface composed of loose, unconsolidated materials such as tiny mineral particles, decayed organic matters, living organisms, water and air. Living organisms include vegetation, bacteria and animals. A square metre of fertile soil brings forth more than 1,000 million individual forms of life, from microscopic organisms to insects, worms and large animals such as burrowing rodents, rats etc. Animals living in soil play an important role in biological processes of soil. Burrowing animals like ants, rodents, termites and some birds move the surface soil down wards and subsoil upwards. The mixing of two layers helps in improving the texture and it’s aeration.

A variety of biological factors influence soil formation. Plants stabilise the earth by reducing erosion and surface run off. As they decay, the plants also provide the fine organic humus litter vital to soil life. The dead bodies of organisms and the wastes of biological process do not pileup. They are broken down and their component parts are recycled by the community. The soil organisms decompose the dead leaves and transform into an amorphous mass of decaying and decomposing plant tissues, finally reducing them to the mineral elements from which they were once synthesised. The role of soil bacteria is crucial for they not only fix nitrogen from the air in a form that plants can use, but also promote the process of decay. All these organisms help in the maintenance of nutrient cycles in the soil.

It is imperative to discuss here the role played by the earth worms in soil formation. Of the various types of beneficial organisms, earth worm is perhaps the most important. They play a vital role in soil turn over, aeration, decomposition, fertility, cycling of matter and so on. Besides various roles as cited above, earth worms have immense importance in the ecological food chain as they are the major food source for some insects, amphibians and birds. Earth worms work like a crusher machine as they help in reducing it’s grains to small size and in mixing the minerals and the organic matters. Earth worms rework the soil not only by burrowing but also by passing the soil through these intestinal tracts. It has been estimated that earth worms alone can turn over between one and ten tonnes of soil per hectre per year. As they eat and excrete the soil, they also change it’s texture and composition. Earth worms may burrow two metres into the soil, make numerous transverse burrows and produce worm casts by eating the soil and soil organic matter. These casts are very rich in nitrogen and mineral substances and increase soil fertility. The burrows facilitate aeration and increase water holding capacity. Thus the soil turn over provides a stone free layer about 15cm deep on the surface. The degradation of organic waste by earth worm is known as vermi Composting.

Soil erosion is a serious problem in most tropical countries and more so in India. This ultimately reduces the land productivity. The main causes of soil-erosion are deforestation, unscientific method of cultivation (i.e. Jhumming), over grazing, wind and running water. Human interference in the ecological system is the major cause of concern because it is destroying the ecological balance in an irreversible manner. Soil erosion is one of the causes of eco-imbalance. In India, there are problems of soil-erosion in many States such as Jammu and Kashmir, Himachal Pradesh, Uttar Pradesh, Bihar, Assam, Arunachal Pradesh, Sikkim, Rajasthan, Madhya Pradesh etc. It has been estimated that in India 53 per cent of the area is suffering from soil erosion.

All our activities affect the natural world in one way or the other. As our population continues to grow and our material prosperity continues to increase, our impact will also become progressively more damaging. Our survival depend only on maintaining the natural world in productive stage. It we are to maintain this State, the onus of responsibility lies on the shoulders of every citizen. We have not inherited this earth from our ancestors, but we have borrowed it from our children. We are, therefore, obliged to preserve it and handover to them in a healthy State.
(Published on the occasion of World Earth Day). ASSAM TRIBUNE

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