干旱区季节性湖泊面积动态变化及蒸发量——以艾丁湖为例

Dynamic variation and evaporation of seasonal lakes in arid areas:A case study for the Aiding Lake

干旱区湖泊对气候变化和人类活动的影响极为敏感,湖泊面积变化是区域水循环和水平衡改变的结果。以新疆吐鲁番艾丁湖为例,利用陆地卫星遥感影像采用水体指数法解译了艾丁湖1986—2018年的湖泊面积变化,分析了湖泊面积变化与区域气候变化、河流径流量变化的相关关系,并分析了艾丁湖历年最大湖水容积和湖面蒸发量变化。结果表明:艾丁湖最大湖面面积一般在3月,湖泊最大面积的年际变化规律与入湖河流径流变化基本一致,自1980年代中期以来,东天山冰川萎缩造成河流径流增加,艾丁湖总体呈增大趋势;1996—2006年计算的最大湖水容积要明显大于湖水蒸发量。2006年以后随径流增加趋势减弱,湖面面积缩小。干旱区气温变化导致冰川萎缩影响的河流径流量是影响干旱区河流尾闾湖泊面积变化的决定性因素。

Lakes in arid areas are very sensitive to climate change and human activities,and lake area variations are controlled by changes and balance in the water cycle.Taking the Aiding Lake in Turpan,Xinjiang,as an example,this paper used Landsat remote sensing images and the water index method to interpret the lake area of 1986-2018.The relationships between lake area and regional climate change and river runoff changes were analyzed.The interannual variations of lake water storage and lake evaporation throughout the years were also evaluated.The results show that the maximum surface area of the Aiding Lake generally occurs in March,and the interannual variations of the largest area of the lake are basically consistent with changesin river runoff into the lake.The maximum lake volume calculated during 1996-2006 was significantly larger than the evaporation capacity of the lake.After2006,the lake area decreased with the decline in runoff rates.River runoff affected by glacier shrinkage due to temperature change in arid regions is the decisive factor affecting change sin lake area in the wake of rivers in arid regions.