Carbon sequestration with land-use cover change in a Himalayan watershed

Based on satellite imagery for 1988 and 2001, land-use cover change and associated carbon stock and flux as a result of changes were estimated in Mamlay watershed of Sikkim Himalaya, India. The total area of forest was decreased by 28%, whereas open cropped area increased by more than 100%. The conversion of forests into other land uses resulted in a remarkable decline in the C densities. Across the land-use cover, total mean C densities ranged from 46 Mg ha(-1) in open cropped area temperate to a high of 669 Mg ha(-1) in temperate natural dense forest. The heavily converted areas lost an estimated 55% of their total 1988 C pools, whereas the low-impacted areas lost only 0.12%. Changes in land use released 7.78 Mg C ha(-1) yr(-1), demonstrating that land-use changes significantly affected C flux. Therefore, the conversion of forest to agriculture land should be reversed. Agroforestry systems should be included in agricultural land in mountainous regions. The policy relevance of this work is immediate. The results of this study will provide direct input to industrialized countries to meet their Kyoto Protocol emission-reduction obligations. (c) 2007 Elsevier B.V All rights reserved.