潼关河床高程演变规律研究

潼关河床在历史时期就是缓慢上升，三门峡水库建成后加剧了上升速度，潼关河床的升降有多种因素：潼关上下游冲淤变化，干支流来水来沙及其不同组合、库水位变动等，黄河上游龙羊峡等水库的调节作用，也有一定影响，通过实测资料分析，得到基本规律，给出估算方法，预估出不同水沙系列的潼关高程发展趋势，有利水沙系列，潼关高程基本稳定，不利水沙系列，将逐年上升。

Study on variation of channel elevation at Tongguan on the Middle Yellow River

The river bed at Tongguan rose gradually during the historic period, but the riasing speed was accelerated after the construction of the Sanmenxia reservoir. There are several factors which influence the river bed elevation, for instance, the erosion and deposition in upstream and downstream reaches of Tongguan, the oncoming water and sediment from the main stream and the tributaries and their different meeting opportunities, and the variation of water stage at the dam site. Regulation of water and sediment of upstream large reservoirs such as the Longyangxia reservoir also produces a certain impacts on the river bed elevation. By analyzing the field measured data, The paper summarizes some basic laws and presents the methods of evaluation and prediction of the developing tendency for the river bed elevation at Tongguan. It should be realized that the river bed elevation at Tongguan would be basically steady under favorable water and sediment conditions, however, it would raise if the oncoming flow and sediment are unfavorable.