Determining soil redistribution in Dian Lake catchment by combined use of caesium-137 and selected c

Recent development in the use of the environmental radionuclide caesium-137 for documenting rates and patterns of soil redistribution on the cultivated or uncultivated land and estimating rates of sediment deposition on floodplains represents an important advance that overcomes many of the limitations' of the conventional techniques commonly applied in such investigations.A study on soil redistribution (including soil erosion and deposition) was carried out in the Dian Lake catchment,Yunnan Province,using 137Cs and selected chemical properties.The average soil erosion rate was 1,280.2 t km-2yr-1.Soil erosion rate occurring on different parts of the slope was significantly different on different parts of the slope,increasing from the top,the bottom to the middle slope.The average soil erosion rate is also different with the land use type and that of the cultivated land (1,672.8 t km-2 yr-1) is higher than of the uncultivated land (1,161.2 t km-2yr-1).The result shows that landform,slope gradient and land use type are key factors that influence the size of soil erosion.In addition,we also find the SOC and TN contents and amount of the soil erosion to be correlated in the soil.With the soil erosion occurring,there are land degradation and the local eco-environmental problems,such as water eutrophication in Dian Lake