Desertification in India
The chief causes of desertification are:
(i) Climatic factors,
(ii) Human factors (human cultures). Recent changes in land use and population density had much ecological effects. Human factors are population growth and increased density, reduced nomadism and loss of grazing lands,
(iii) Interactions between climate and culture
The causes of deforestation and denudation are well known. The principal causes have been the population explosion leading to enhanced requirement of timber and fuel wood and grazing respectively. Increasing number of livestock and migrating graziers contributed to degradation of forests and the consequent devastation. The most assessable forest areas are heavily grazed. For instance, there are nearly 1200 thousand sheep’s and goats in alpine areas of U.P. and in addition there also visit of about 25,000 migratory graziers. There are also about 5-7,000 buffaloes owned by gujars.
It is estimated that in absence of suitable checks, growing forestry stock decreases from 13.79 m3/head in 1981 to 2.66 m3/head in 2001 and reduction in annual availability of grass is from 2.60t/Cattle unit in 1981 to 0.90- t/cattle unit in 2001. Existing forests may thus not be able to meet our wood and fodder requirements of mankind and livestock respectively.
Moreover, increase in shifting (jhum) cultivation in North East and South Orissa has also laid large forest tracts bare. In essence, it is a low energy budget and low investment system of subsistence agriculture that uses rapid mineralisation and recycling of nutrients. There has been shortening of jhum cycle to six years only (in some districts, even 2.3 years only), which provides no enough time for natural repair of damaged ecosystem.
Since long, forests have been looked upon as revenue generation sector and maximum could be extracted from the trees by Govt. and private owners. In the face of agriculturalisation, urbanisation and industrialisation, preservation of forests could be given a very low priority. During 1951 to 1976, India has lost about 4.2 million hectares of forests for such activities. Agriculture claimed maximum 2.5 million hectare.
A major cause of deforestation has been the construction of hill roads (about 30,000 km. long) most of which are in strategic and most fragile belt of Himalayas. Road construction affect the stability of hill slopes, damages the protective vegetation cover both above and below roads, result in debris covering forests vegetation, orchards and agriculture fields, blocked natural drainage, pollutes streams, delays vehicular traffic and causes damage to human life and property.
Industries and mining impose a serious effect on forest areas. In different states large areas have been clear-felled and laid barren as a result of open cast mining of iron ore, mica, coal, manganese, limestone etc. Environment impact of mining includes loss of production (forests, agriculture turned into pastures), loss of top soil, surface water pollution, lowering of ground water table, ore transport hazards (damage to vegetation, soil drainage, water quality and property), sediment production and discharge, fire hazards and air pollution.
Moreover, there has been a tendency for establishing forest based industries without any respect to sustainability of the resource base that leads to over exploitation. There are also hasty approaches to formulation of developmental projects particularly hydro-electric and those on tourism, road building and mining. There has been unlimited exploitation of timber for commercial use. Commercial demand could out-strip supply leading to decimation of forests, particularly the wood.