Xinjiang Institute of Ecology and Geography, CAS, 818 South Beijing Road, Urumqi 830011, Xinjiang, People's Republic of China.
Environ Monit Assess. 2011 Jul;178(1-4):247-56. doi: 10.1007/s10661-010-1686-y. Epub 2010 Sep 10.
Inland lakes are major surface water resource in arid regions of Central Asia. The area changes in these lakes have been proved to be the results of regional climate changes and recent human activities. This study aimed at investigating the area variations of the nine major lakes in Central Asia over the last 30 years. Firstly, multi-temporal Landsat imagery in 1975, 1990, 1999, and 2007 were used to delineate lake extents automatically based on Normalized Difference Water Index (NDWI) threshold segmentation, then lake area variations were detailed in three decades and the mechanism of these changes was analyzed with meteorological data and hydrological data. The results indicated that the total surface areas of these nine lakes had decreased from 91,402.06 km(2) to 46,049.23 km(2) during 1975-2007, accounting for 49.62% of their original area of 1975. Tail-end lakes in flat areas had shrunk dramatically as they were induced by both climate changes and human impacts, while alpine lakes remained relatively stable due to the small precipitation variations. With different water usage of river outlets, the variations of open lakes were more flexible than those of other two types. According to comprehensive analyses, different types of inland lakes presented different trends of area changes under the background of global warming effects in Central Asia, which showed that the increased human activities had broken the balance of water cycles in this region.
内陆湖泊是中亚干旱地区的主要地表水。这些湖泊的面积变化已被证明是区域气候变化和人类近期活动的结果。本研究旨在调查中亚九大湖泊在过去 30 年中的面积变化。首先，利用 1975 年、1990 年、1999 年和 2007 年的多时相 Landsat 影像，基于归一化差异水体指数（NDWI）阈值分割自动划定湖泊范围，然后详细分析了三十年来的湖泊面积变化，并结合气象数据和水文数据分析了这些变化的机制。结果表明，1975-2007 年间，这 9 个湖泊的总面积从 91402.06km2减少到 46049.23km2，占 1975 年总面积的 49.62%。由于气候变化和人类活动的双重影响，平原地区的尾部湖泊急剧收缩，而高山湖泊由于降水变化较小而相对稳定。由于出水口的不同用水方式，开阔湖泊的变化比其他两种类型更加灵活。综合分析表明，在全球变暖影响下，不同类型的内陆湖泊呈现出不同的面积变化趋势，这表明人类活动的增加打破了该地区水循环的平衡。
