Land use and land cover change within the Koshi River Basin of the central Himalayas since 1990

Land change is a cause and consequence of global environmental change. Land use and land cover have changed considerably due to increasing human activities and climate change, which has become the core issue of major international research projects. This study interprets land use and land cover status and the changes within the Koshi River Basin (KRB) using Landsat remote sensing (RS) image data, and employs logistic regression model to analyze the influence of natural and socioeconomic driving forces on major land cover changes. The results showed that the areas of built-up land, bare land and forest in KRB increased from 1990 to 2015, including the largest increases in forest and the highest growth rate in construction land. Areas of glacier, grassland, sparse vegetation, shrub land, cropland, and wetland all decreased over the study period. From the perspective of driving analysis, the role of human activities in land use and land cover change is significant than climate factors. Cropland expansion is the reclamation of cropland by farmers, mainly from early deforestation. However, labor force separation, geological disasters and drought are the main factors of cropland shrinkage. The increase of forest area in India and Nepal was attributed to the government's forest protection policies, such as Nepal's community forestry has achieved remarkable results. The expansion and contraction of grassland were both dominated by climatic factors. The probability of grassland expansion increases with temperature and precipitation, while the probability of grassland contraction decreases with temperature and precipitation.