ENVIRONMENTAL SCIENCE : NATURAL RESOURCES 19
scale deforestation has badly affected the weather facing almost each year more of
bleak than the normal weather.
(d) The increase in shifting (jhum) cultivation in North east and Orissa has also laid
large in forest tracts bare. As the jhum cycle is shortened to six years only (in some
districts, even 2-3 years only), too short period does not provide enough time for
natural repair of damaged ecosystem.
(e) A major cause of deforestation has been the construction of hill roads. About a
decade back, they were about 30, 000 km long. Most of these roads are in state and
most fragile belt of Himalayas. Road construction damaged the protective vegetation
cover both above and below roads. It blocked natural and pollution streams.Formidable Picture of Deforestation
Deforestation has been causing tremendous land erosion and land slides. India is losing
about 6,000 million ton of top soil annually due to water erosion in the absence of trees. The
loss worked out from the top soil erosion in 1973 was Rs. 700 crore, in 1976, 1977 and 1978
it was Rs. 889 crore. Rs. 1,200 crore and Rs. 1,091 crore respectively. The figures in recent
years have risen formidably too high. Increasing number of livestock and migrating glaziers
have led to degradation of forests and the consequent devastation. Data show that about two
decades back these were nearly 1200 thousand sheep and goats in alpine areas of U.P. In
addition, there also visited about 25,000 migratory graziers. There were also about 5-7,000
buffaloes owned by Gujars. Consequently, the forestry stock decreased from 13.79 m3/head
in 1981 to 2.66 m3/head in 2001.
The following table shows that there has been a grave reeducation in forest land:Land use Area (Mha) Change in forest cover (%)
of total geographical are
of the country
1972-75 1980-82
(a) Forests land Closed 46.10 35.43 (–) 3.25
forests Open/degrated
forests Mangroves 8.80 10.00 (–) 3.25
Mangroves 0.30 0.27 (–) 0.02
55.20 (16.83%) 45.70 (39.94%) (–) 2.89
(b) New-forest land
Agricultural land, 255.70 267.40 (+) 3.58
grassland, shrub land,
non-forest planation,
barren land
(c) Others 17.12 14.86 (–) 0.69
Areas under snow, fog,
cloud, shadow etc.(d) Total 328.00 328.00**Excluding Andaman & Nicobar Island (based on NRSA, 1984).