鄱阳湖湖泊与陆地水储量变化及相关分析

Variation and Correlation Analysis of Lakewater Storage and TerrestrialWater Storage Anomaly in Poyang Lake

受人类活动和气候变化影响,鄱阳湖水文情势发生了改变,掌握鄱阳湖水储量变化对流域水资源综合利用具有重要意义。利用GEE平台分析2003-2020年长系列逐月湖泊面积变化趋势,结合实测水位计算鄱阳湖湖泊水储量变化;利用GRACE的Mascon产品数据计算湖区陆地水储量变化,分析湖泊水储量与陆地水储量的变化关系。结果表明:基于GEE平台提取的湖泊面积、利用GRACE数据反演的陆地水储量变化的长期趋势与星子站实测水位变化一致,遥感影像显示湖区南部水体面积变化较小,常年有水范围面积更大,GRACE数据也表明南部多年平均陆地水储量较北部略高;湖区陆地水储量变化与星子站水位突变检验表明二者突变点一致,小波分析表明体积法计算的湖泊水储量变化与陆地水储量变化相关性显著,鄱阳湖陆地水储量受湖泊水储量变化影响大。

Due to human activities and climate change,the hydrological regime of Poyang Lake has undergone significant changes.Understanding the variation in its water storage is of great significance for the comprehensive utilization of water resources in the basin.In this study,we used the Google Earth Engine(GEE)platform to analyze the long-term monthly trends of lake area changes from 2003 to 2020 and combined them with measured water levels to estimate the variation in water storage of Poyang Lake.We also calculated the variation in terrestrial water storage in the lake area using the GRACE Mascon product data and analyzed the relationship between the variation in lake water storage and terrestrial water storage.The results showed that the long-term trends in the extracted lake area based on the GEE platform and the variation in terrestrial water storage retrieved from GRACE data were consistent with the measured water level changes at the Xingzi station.Remote sensing images indicated that the water body area in the southern part of the lake changed slightly,and the area with perennial water expanded.The GRACE data also manifested that the average terrestrial water storage in the south part was slightly higher than that in the north.The consistency between the abrupt change points in the variation of terrestrial water storage and the water level at Xingzi station was confirmed by a change point analysis.Wavelet analysis revealed a significant correlation between the variation in lake water storage calculated using the volume method and the variation in terrestrial water storage.Moreover,the variation in lake water storage had a significant impact on the variation in terrestrial water storage of Poyang Lake.