1957—2016年泾河干流径流量变化趋势分析

Changes of Runoff in the Jinghe River Basin in 1957-2016

泾河为渭河的第一大支流,为了解泾河干流径流量变化特征,以泾河干流甘肃段的4个水文站1957—2016年的实测数据为基础,利用Mann-Kendall法、累积距平法和小波变换法对泾河干流的径流量变化趋势、径流量突变年份和周期变化规律进行分析,并对引起变化的可能原因进行探讨。结果表明:泾河干流甘肃段的崆峒峡水文站、平凉水文站、泾川(三)水文站和杨家坪(二)水文站1957—2016年年径流量呈下降趋势,且4个水文站径流量突变后年平均值较突变前分别减少了41%、44%、45%和41%;主要存在2~10 a尺度、10~30 a尺度和30 a以上大尺度的周期性变化;径流量突变年份集中在1982年和1986年;从崆峒峡水文站到杨家坪(二)水文站之间的泾河天然径流量与实测径流量之间的差异逐渐增加,且甘肃段泾河干流由上游至下游中小尺度周期性逐渐减弱,大尺度周期性逐渐增强。

The Jinghe River is the largest tributary of the Weihe River.In order to reflect the hydrological characteristics of the main stream of the Jinghe River,it was proposed to use the measured data from 1957 to 2016 of 4 hydrological stations on the main stream of the Jinghe River in Gansu as the basis and using the Mann-Kendall method and accumulating anomalies.The method and wavelet transform method were used to analyze the trend of runoff change,the year of runoff abrupt change and the law of periodic change in the main stream of Jinghe River,and the possible reasons for the change were discussed.The results show that the runoff of Kongtongxia Hydrological Station,Pingliang Hydrological Station,Jingchuan(3)Hydrological Station and Yangjiaping(2)Hydrological Station on the mainstream of Jinghe River in Gansu Province has shown a downward trend in the past 60 years,and the annual runoff average values after the sudden change of the 4 hydrological stations are reduced by 41%,44%,45%,and 41%respectively compared with that before the sudden change;there are mainly large-scale periodic changes of 2-10 years,10-30 years and more than 30 years;The abrupt flow years are concentrated in 1982 and 1986;the difference between the natural flow of the Jinghe River from the Kongtongxia Hydrological Station to Yangjiaping(2)and the measured runoff is gradually increased,and the small-to-medium-scale periodicity in the lower reaches of the Jinghe River in Gansu,the upstream to downstream is gradually weakened and the large-scale periodicity gradually increases.