The impact of agricultural soil erosion on biogeochemical cycling

Soils are the main terrestrial reservoir of nutrients, such as nitrogen and phosphorus, and of organic carbon. Synthesizing earlier studies, we find that the mobilization and deposition of agricultural soils can significantly alter nutrient and carbon cycling. Specifically, erosion can result in lateral fluxes of nitrogen and phosphorus that are similar in magnitude to those induced by fertilizer application and crop removal. Furthermore, the translocation and burial of soil reduces decomposition of soil organic carbon, and could lead to long-term carbon storage. The cycling of carbon, nitrogen and phosphorus are strongly interrelated. For example, erosion-induced burial of soils stabilizes soil nutrient and carbon pools, thereby increasing primary productivity and carbon uptake, and potentially reducing erosion. Our analysis shows soils as dynamic systems in time and space.