摘要
Land use and land cover changes that occurred during the period from 1991 to 2001 in the Jahlma watershed of the Lahaul valley,a cold desert region of the northwestern Himalaya,were evaluated using land use data and visual interpretation of IRS Satellite imageries. The results revealed that out of the six major land use forms within the watershed,land areas under agriculture,kitchen garden and settlement land were found increased,whereas a declining trend was recorded in areas under grassland,barren land and Salix plantation. The cultivated land within the watershed increased from 54.87 % (total of agriculture land,kitchen garden,grassland,barren land,Salix plantation and residential area) in 1991 to 56.89 % in 2001,corresponding to an expansion of 4.41 ha. On the other hand,the areas of grassland decreased from 31.41 % in 1991 to 29.81 % in 2001. Such a dramatic land use and land cover changes taking place within the 33 km2 watershed area in a single decade clearly indicates the prevailing danger of land degradation and environmental deterioration in the region.
Land use and land cover changes that occurred during the period from 1991 to 2001 in the Jahlma watershed of the Lahaul valley, a cold desert region of the northwestern Himalaya, were evaluated using land use data and visual interpretation of IRS Satellite imageries. The results revealed that out of the six major land use forms within the watershed, land areas under agriculture, kitchen garden and settlement land were found increased, whereas a declining trend was recorded in areas under grassland, barren land and Salix plantation. The cultivated land within the watershed increased from 54.87 % （total of agriculture land, kitchen garden, grassland, barren land, Salix plantation and residential area） in 1991 to 56.89 % in 2OOl, corresponding to an expansion of 4.41 ha. On the other hand, the areas of grassland decreased from 31.41% in 1991 to 29.81% in 2001. Such a dramatic land use and land cover changes taking place within the 33 km^2 watershed area in a single decade deafly indicates the prevailing danger of land degradation and environmental deterioration in the region.
