Author(s): Cheng Liu; Yun He; Jianguo Chen
Keywords: River; Sediment load; River basin; Reservoir; Human activity
Abstract: The magnitude of global fluvial discharge of sediment to the coasts provides an important and sensitive indicator of changes in the operation of the Earth System, and it exerts significant influences on the global socio-economic and environmental problems in a certain extent. It is this reason that the study on global land-ocean sediment flux has attracted attentions of many scholars. Due to the lack of reliable and complete fluvial sediment data, it is difficult to estimate the amount and changes of global land-ocean sediment flux, with wide different estimated values without common acceptance. In this paper estimations of the global fluvial discharge of sediment to the coasts proposed by 27 papers are collected and recent typical relevant studies are reviewed. The latest understandings of estimations in prehumen and modern global sediment fluxes are put forward. In recent years the estimates of the global fluvial land-ocean sediment flux have provided more consistent results, tending to converge in the range of 12-20 Gt/yr. It is proposed by the authors through analysis that the amounts of prehumen and post-dam global land-ocean sediment fluxes can be adopted as 19 Gt/yr and 13 Gt/yr, respectively, and the reduction in the fluvial sediment load associated with reservoir trapping is about 24 Gt/yr.