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Changes in Water Surface Boundary of East Juyan Lake in Northwest China Based on Remote Sensing Data

Lakes in arid inland areas are important indicators for reflecting the regional ecosystem security under climate change and human-related impacts. Understanding the evolution characteristics of lakes is helpful for eco-environment protection and management. This study applied the Landsat remote sensing data from 2002 to 2017 to analyze the water surface area changes of East Juyan Lake, a closed lake in northwest China. The results showed that the upward trends existed from 2002 to 2006 and were more significant from 2014 to 2017. The upward trends became gentle from 2007 to 2013. Regarding the seasonal characteristics, the water surface area in winter was almost the largest in the whole year, with an annual average of 51km2, followed by that in autumn (50.45km2). The annual average value in spring (48.16km2) was larger than that in summer (41km2). For the spatial changes, the lake boundary generally expanded from 2002 to 2009, and its eastern and western boundaries changed obviously after 2006. After 2010, the changes in lake boundaries tended to be gentle.