Study on spatiotemporal variations of sediment load and driving factors in the Songhua River Basin
Based on the long-term sediment load data in the Songhua River Basin,the spatiotemporal variation characteristics of sediment transport were analyzed by using the M-K trend test and Pettitt change point test methods,and the partial least squares structural equation model was used to quantitatively differentiate the contribution of different factors to sediment yield changes.The results show that both the increasing trend of sediment transport in the upper and middle reaches of the Nen River and the middle and lower reaches of the mainstream of Songhua River,and the decreasing trend of sediment transport in the lower reaches of the Nen River,the Second Songhua River area,and the upper reach of the mainstream of the Songhua River reach to a significant lever with P＜0.01.However,there exist the significant abrupt changes of sediment transport series in each river basin area.The sediment transport modulus in the basin shows a spatial pattern of lower in northwest and higher in southeast,with the main sediment erosion and yield areas including the upper and lower reaches of the Nen River,various tributaries of the Second Songhua River,and the middle and upper reaches of the mainstream of Songhua River.Precipitation,runoff,NDVI,and RI are the dominant factors affecting sediment transport changes,which jointly explaining 61.6％,71％,and 47.3％of sediment yields changes in the three major sub-basins.The spatial and temporal pattern changes of sediment transport in the Songhua River basin and its driving factors will provide a basis for future allocation of soil and water conservation measures and response to extreme rainstorm erosion disasters.
Songhua River Basinsediment loadspatiotemporal variationsdriving factors
万方数据
维普
