1954-2018年东平湖水位变化特征及驱动因素分析

依据东平湖1954-2018年水位资料,采用Mann-Kendall突变检验、小波分析等方法,分析了1958-2018年东平湖的水位变化特征,探讨了其变化的自然和人为因素。研究结果表明:1958-2018年东平湖水位年际变化幅度较大,总体呈现中-低-高的变化特征;年际水位周期变化具有28a和40a的时间尺度特征。人类活动影响下的入湖径流量变化是东平湖水位变化的主要因素,气候因素也起到一定程度的作用。1958年之前,东平湖与黄河自然联通,水位变化受黄河和大汶河来水影响较大; 1958年以后,东平湖与黄河水文系统被人为控制,水位变化主要受大汶河入湖径流量变化的影响; 1970年以后,气候变暖加剧,降水量增加影响了水位的变化; 2013年南水北调东线工程实施后,人为因素的影响进一步加大。

Characteristics and driving factors of water level variations of Dongping Lake between 1954 and 2018

According to the water level records of Dongping Lake of recent 65 years (1954-2018), Mann-Kendall mutation test and Morlet analysis were used to analyze the water level variation characteristics of Dongping Lake between 1954 and 2018, and the influencing factors of nature and human activities were discussed. The results showed that the inter-annual water levels of Dongping Lake in the past 65 years changed greatly, and the overall characteristics showed a medium-low-high variation trend, with the periodic time-scale features of 28 years and 40 years. The change of inflow runoff under the influence of human activities was the main factor of water level variations in Dongping Lake, and the climatic factors played an important role too. Due to the natural connection between Dongping Lake and the Yellow River, the water level of Dongping Lake was greatly affected by the inflow from the Yellow River and the Dawen River before 1958. Since then, the hydrological system of Dongping Lake and the Yellow River was artificially controlled, so the water level of Dongping Lake was mainly affected by the inflow from Dawen River. The water level changed accordingly after 1970, due to the increase of precipitation caused by the worsening of globalwarming. In addition, the impact of the human activities further increased after the implementation of the East Route Project of South-to-North Water Transfer in 2013.