Guanghui ZHANG;Yang YANG;Yingna LIU;Zhiqiang WAN

State Key Laboratory of Earth Surface Processes and Resource Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing 100875 (China);School of Geography, Faculty of Geographical Science, Beijing Normal University, Beijing 100875 (China;School of Geography, Faculty of Geographical Science, Beijing Normal University, Beijing 100875 (China)

sediment deposition;deposition;the black soil region of northeast china;hillslope;region;studie

Sediment deposition is one of the most significant processes in small watershed characterized by gentle long hillslope in the black soil region of northeast China, which implies by severe ephemeral gully and gully erosion on hillslope, and very low sediment concentration in river system. Few studies have been performed to summarize the related researches in this region. The objectives were to identify the potential influencing factors on sediment deposition, review the related studies and propose the future research needs in the black soil region of northeast China. Sediment deposition is controlled by the deficit between sediment transport capacity of flow and sediment load. Hence, all factors affecting transport capacity and sediment load directly impact sediment deposition. For a specific small watershed, the change in slope gradient along the flow path is the key factor affecting sediment deposition. Shelter belt, ridge tillage system, terrace, grass strip, road distribution, pond and reservoir, land use pattern also influence the spatial distribution and rate of deposition. The trace method is widely utilized to quantify sediment deposition in this region. The results of 137Cs, 210Pb and magnetic susceptibility reveal that serious deposition occurs at back and foot slopes. Distinct deposition occurs in front of contour shelter belt. The future studies of deposition should focus on the methodology, the spatial and temporal variations, the dominant influencing factors and their mechanisms, and the potential effects on land productivity within specific small watersheds and across the black soil region. This study is helpful to insight into sediment deposition process in small watershed characterized by gentle long hillslope.