Soil Erosion and Nutrient Losses in Highly Degraded Soils (Oxisols) of the Eastern Savannas of Colombia

Ramirez-Avila, J. J., Almansa, E. F., & Ortega-Achury, S. L. (2011). Soil Erosion and Nutrient Losses in Highly Degraded Soils (Oxisols) of the Eastern Savannas of Colombia. Proceedings International Symposium on Erosion and Landscape Evolution ASABE Specialty Conference. Anchorage, Alaska: American Society of Agricultural and Biological Engineers (ASABE).

A 4-yr study was carried out in the Eastern Savannas of Colombia ecosystem, considered an important region for potential expansion of agricultural production in Colombia. The goal was to determine the impact of water erosion on soil productivity for a representative Oxisol on the Eastern Savannas of Colombia. The region is characterized by rain seasonality and high precipitation erosivity, high soil erodibility and vulnerability to degradation and low soil fertility. Water erosion is one of the most important limitations for sustainable agricultural development of the ecosystem. The quantitative and temporal variation of runoff, soil erosion and eroded nutrients were determined on a 4% slope high terrace Oxisol (Typic Hapludox) by establishing 50 m 2 erosion plots with different soil cover types, which included bare soil, an annual rotation system (rice-soybean), and natural ungrazed pastures (Brachiaria decumbens). The effect of soil erosion on crops yield was determined, being more evident on soybean production (45% of reduction in three years). Results are intended for the development and establishment of sustainable agricultural production systems in the Eastern Savannas of Colombia.