近30年中国典型区域水体面积变化与归因

在生态文明建设中,水域空间率是一项重要的指标。一般情况下,某个区域中的水体面积越大生态环境越好。而水体面积又受到气候变化与人类活动的双重影响。中国水体面积的变化规律及归因是生态文明建设中一个关键的科学问题。在全国范围内,根据气候条件和经济发展情况,选取了9个研究区域。基于Google Earth Engine云计算平台,使用多个光谱指数组合的方法,对1986-2018年的Landsat影像进行水体提取。采用Mann-Kendall法分析了水体面积动态变化特征,并借助双累积曲线法和分布式水文模型,进一步计算了气候变化和人类活动对水体面积变化的贡献率。结果表明:(1)半干旱半湿润地区受人类活动影响剧烈,水体面积变化显著;(2)湿润地区受气候变化影响,水体面积显著增加;(3)人类对水资源的过度使用、跨流域调水以及水库修建直接决定大部分区域的水体面积变化。该研究能够为生态文明建设提供科技支撑。

Changes and attribution of water surface area in typical regions of China in the past 30 years

The water surface area ratio is an important indicator of ecological construction.In general,the larger the water area in a region,the better the ecological environment.The water area is affected by both climate change and human activities.The law and cause of water surface area change in China are key scientific issues.In this study,nationwide 9 research areas were selected based on climatic conditions and economic development levels.Based on the Google Earth Engine cloud computing platform,the Landsat image was used to extract water surface area from 1986 to 2018 using the method of combining multiple spectral indices.The dynamic variation of water surface area was analyzed by Mann Kendall test.The contribution of climate change and human activities to water surface area changes were further calculated by double mass analysis and a distributed hydrological model.The results showed that semi arid and semi humid areas were strongly affected by human activities,and there was a significant change was observed in water surface area.Humid areas were affected by climate change,and the water area was also significantly increased.Human activities such as excessive use of water resources,water transfer projects and reservoir construction directly determined changes in water surface area in most areas.This research can provide scientific support for ecological construction.