汉江中下游皇庄站年最低水位变化及成因分析

Change and cause analysis of annual lowest water level of Huangzhuang Station in middle and lower reaches of Hanjiang River

近年来汉江中下游多次出现特枯低水位,为探究其原因,分析了1950~2022年汉江中下游干流皇庄站年最低水位变化趋势,并分析了断面、流量、含沙量等引起年最低水位变化的影响因素。结果表明:1950~2022年,皇庄站年最低水位呈明显波动下降趋势。皇庄站历年年最低水位的最高值出现在1954年的1月,为43.59 m;最低值出现在2022年的10月,为38.47 m;多年平均值为41.29 m。最高值与最低值之间变幅为5.12 m。河段的持续冲刷下切是影响皇庄站年最低水位变化的最显著因素;受上游水库群的调蓄及河段内丁坝等航道整治工程影响,皇庄站过水断面持续冲刷下切,导致皇庄站年最低水位变化。

In recent years,the low water level of middle and lower reaches of Hanjiang River had appeared for many times.In order to study and analyze the potential causes,we analyzed the trend of annual lowest water level change of Huangzhuang Station from 1950 to 2022.The influencing factors of annual lowest water level change,such as section,discharge and sediment were analyzed.The results showed that during the period from 1950 to 2022,the annual lowest water level of Huangzhuang Station showed an obvious trend of fluctuation and decreased.The highest value of annual lowest water level in Huangzhuang Station appeared in January 1954,with a value of 43.59 m.The lowest value occurred in October 2022,with a value of 38.47 m.The average annual value was 41.29 m.The variation between the highest and lowest values was 5.12 m.Continuous erosion down-cutting of river reaches was the most significant factor affecting the variation of annual lowest water level at Huangzhuang Station.Affected by the regulation and storage of upstream reservoirs and the channel improvement projects such as the groin dam in the river reach,the crossing section of Huangzhuang Station continued to erode and cut,resulting in the decreasing of annual lowest water level of Huangzhuang Station.