GEF

Unit 3  |  Primary Sustainability Issues 67 World food aid increases as population growth and food shortages intensify. Climate change is a critical factor that is already reduc- ing access to food resources and jeopardizing crop yields. “Business as usual” agriculture is a significant contributor to climate change, deforestation, biodiversity loss, soil erosion , and water pollution. Agriculture and grazing are responsible for about one-third of global greenhouse gas emissions, mostly due to land clearance and methane emissions from livestock. Large-scale clearing for soybeans, oil palms, and grazing land is deforesting biodiversity hotspots such as the Amazon basin and Indonesia. Soil erosion often results from short-sighted agricultural prac- tices, such as the removal of stabilizing vegetation and plant roots, which leave topsoil vulnerable to being washed away by rain. Topsoil erosion is an especially severe problem in tropical forests that are cleared through slash and burn techniques, as soils in these forests are particularly shallow and easily washed away. In Madagascar, approximately 10 percent of the total land area of the country has been rendered infertile due to soil erosion and poor agricultural management. Modern agriculture is also a significant source of water pollution, as pesticide and fertilizer SOIL EROSION The process in which soil is removed by water or wind. SLASH AND BURN A cultivation technique where farmers clear forests and woodland for agricul- tural fields or pastures by cutting or burning the exist- ing plants.