Indirect Impacts of Climate Change that Affect Agricultural Production: Soil Erosion

Land degradation poses an increasing threat to agricultural production. Under natural conditions, topsoil in the aggregate is renewed at a rate approximately equal to the rate at which degradation occurs. However, much agricultural land degrades at faster than “tolerable rates.” (1976) estimate that more than one-third of cropland topsoil in the USA has been lost in the last 200 years. The U.S. Department of Agriculture (USDA) estimates that combined water and wind erosion from cultivated cropland averages approximately 14 tonnes (t)/ha/yr and considers tolerable rates of soil loss on the vast majority of this land to be between 9 and 11 t/ha/yr (USDA, 1994). The majority of the world’s agricultural soils are probably eroding at a faster pace than soils in the USA.