The human impact on fluvial environment in the Amur River basin

近年来，阿穆尔河流域发生了显著的土地覆盖变化。我们试图利用泛滥平原的沉积物重建阿穆尔河流域的历史环境变化。我们证实了阿穆尔河沿岸泛滥平原上许多地方的河流沉积最近变粗了。铯-137和铅-210的过量放射性核素含量证实了沉积物的上部是在最近几十年内沉积的。我们推测，洪泛平原沉积物的粒度粗化是由于峰值流量的增加和农田扩张和森林减少提供的粗质物质造成的。

Recently, remarkable land cover changes have been occurring in the Amur River Basin. We sought to reconstruct the historical environmental changes in the Amur River Basin using floodplain sediments. We confirmed recent coarsening of the fluvial deposits at many localities on the floodplain along the Amur River. The radionuclide contents of cesium-137 and lead-210 excess confirmed that the upper part of the sediment deposited during the resent several decades. We postulate that the grain size coarsening of the floodplain deposits has ensued from an increase in peak discharge and coarse material supplied by farmland expansion and forest reduction.