人民黄河

黄河水沙变化情势尤其是来沙量变化趋势判断是确定治黄方略的重要依据。选取近年来降雨偏多且减沙程度差异较大的黄河中游13条典型支流为研究对象，分析了极端降雨条件下各流域可能最大来沙量，并推算潼关可能最大来沙量。基于水文频率分析法和历史实测极端降雨组合法设计极端降雨，计算得到河龙区间典型流域极端降雨条件下现状下垫面最大年来沙量为7.67亿t;渭河咸阳站和北洛河■头站现状下垫面极端降雨条件下最大年来沙量分别为0.89亿t和1.10亿t;泾河张家山站现状下垫面极端降雨条件下最大年来沙量为4.49亿t;考虑2012年以来头道拐站最大年来沙量为1.77亿t,现状下垫面极端降雨条件下潼关站可能最大年来沙量为15.92亿t,为历史最大值39.1亿t的41%。

Assessing the changes in water and sediment dynamics in the Yellow River, particularly the trend of sediment load, is crucial for formulating strategies for Yellow River management. This study selected 13 typical tributaries in the He-Long reach and the Jinghe, Weihe, and Luohe Rivers, which had experienced relatively high rainfall in recent years but exhibited varying degrees of sediment reduction. The potential sediment yield under extreme rainfall conditions in these basins was analyzed, and the sediment load at Tongguan Station was estimated. Based on hydrological frequency analysis and historical extreme rainfall combinations, extreme rainfall scenarios were designed. The results show that under current underlying surface conditions, the maximum annual sediment yield from typical basins in the He-Long reach during extreme rainfall events accounts for up to 35% of the historically measured maximum annual sediment yield. Using this 35% ratio, the estimated sediment yield from the He-Long reach under extreme rainfall and current underlying surface conditions is 767 million tons. Under the same conditions, the sediment yields at the Xianyang Station on the Weihe River and the Zhuangtou Station on the Beiluo River are 89 million tons and 110 million tons, respectively. The potential maximum sediment yield from the upper reaches of the Jinghe River at the Zhangjiashan Station is 449 million tons. Considering the maximum sediment transport of 177 million tons recorded at the Toudaoguai Station since 2012, the potential maximum sediment load at the Tongguan Station under extreme rainfall and current underlying surface conditions is estimated to be 1.592 billion tons, which is 41% of the historical maximum of 3.91 billion tons.