Deforestation is the permanent removal of trees to make room for other land uses. It leads to greenhouse gas emissions and global warming by reducing the number of trees that absorb carbon dioxide. The top five causes of deforestation are agricultural expansion, livestock ranching, logging, infrastructure expansion, and overpopulation. In Nepal, over-harvesting of fuelwood and fodder, forest fires, grazing, slash and burn cultivation, and timber extraction are the major causes of deforestation. Between 1990 and 2005, Nepal lost 24.5% of its forest cover, or around 1,181,000 hectares, with an annual deforestation rate decreasing from 1.9% to 1.35% over that period