Preferential erosion of black carbon on steep slopes with slash and burn agriculture

In this study we investigated the quantitative and qualitative aspects of soil organic matter (SOM) losses caused by water erosion within a small catchment in Northern Laos, under steep slopes and slash and burn agriculture. The soils in the region have a high contribution of black carbon to soil organic matter and high erosion rates. The aim of the study was to quantify the erosion of black carbon and to identify the processes involved. The conceptual approach included the measurement of contents of SOM, black carbon and mineral bound SOM in bulk soils, sediments eroded from 1 m² plots and in sediments at the outlet of the 0.6 ha catchment. Additionally, the enrichment factors of bulk SOM, BC and mineral bound SOM were calculated for eroded sediments.