The Effects of Deforestation
Soil Erosion:
Removal of vegetation and increasing pressure of grazing in the Siwaliks as elsewhere has affected 0.25 million ha of land in Punjab alone, of this 0.18 million ha in one district of Hoshiarpur. The soil loss by water erosion in grazed Cho land has been found to be 2.24 tons per ha as compared to 0.32 tons per ha in grass and scrub land under similar slope and storm conditions.
Sedimentation of Reservoir:
Careless use of watershed forests and grasslands has caused excessive sedimentation thereby drastically reducing the effective life span of our multi-purpose reservoirs and adversely affecting hydro-electric and irrigation facilities created at great expense.
Floods:
Excessive run-off and silt load due to lack of vegetation in their watersheds has rendered many a river flood-prone. About 40 million ha have been estimated to be prone to flooding. The annual average works out to 11.8 million ha with 5.4 million ha of cropped area. In terms of money average annual damage to crop, house and public utility during last 25 years has worked out to Rs.247 corers and damage to crops alone accounted for Rs.168 cores.
Drought:
Like flood, drought is also the manifestation of misuse of vegetation. The significance of drought can be visualized from its impact on the total production system of the country.
Scarcity of Firewood and Timber:
It is estimated that by 2025 A.D. the demand for wood is expected to be more than 20.7 million m3 and the firewood need will rise to 250 million m3 as against 150 million m 3. Roughly 45 per cent of house hold energy is met from noncommercial sources such as agricultural waste, cow dung and firewood. Lack of firewood results in burning of 3 to 4 million tons of wet dung as fuel annually which is estimated to be more than one third of commercial fertilizer applied. This means that in addition to increasing productivity of our existing forests the country has to put at least another 35 million ha under energy plantation, besides 9 million ha under production forests.
Scarcity of Fodder:
The number of animals grazing in forests has been from 35 million in 1956 to more than 60 million, registration a rise tom per cent. This means that the safe carrying capacity of 1.55 ha per year has already been far exceeded. This has adversely affected the process of natural regeneration and hence conservation of forest resource.