全球变化知识资源中心

Understanding the response of past soil erosion to climate change and human disturbances is quite essential for managing and preventing soil erosion in the future. Here, we report a high-resolution soil erosion sequence during the past 2000 years based on grain-size data from a sediment core GS07A in Tianchi Lake in the Chinese Loess Plateau. These grain-size data are analysed by end-member modelling and further deciphered by detailed modern investigations of surface sediments, surface soils, and modern dust samples aided by published grain-size distribution characteristics of different depositional provenances and processes. Six strong soil erosion periods, including more than 20 serious soil erosion events, are inferred at 150-300 CE, 450-750 CE, 900-1100 CE, 1200-1400 CE, 1650-1800 CE, and 1950-2000 CE. These soil erosion records correspond well with intensive flood events in downstream rivers and the neighbouring Longxi area documented from the historical literature, suggesting that regional high-intensity rainfall or flood events are the main cause of soil erosion. Vegetation cover in the catchment also influenced soil erosion: light vegetation cover aggravated soil erosion even in the periods with a low frequency of flooding, while heavy cover reduced soil erosion even in the periods with a high frequency of flooding. Our results highlight the role of sustainable land use and vegetation restoration around the catchment in controlling soil erosion in the Chinese Loess Plateau.