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高原湖泊对气候变化极为敏感,通过湖泊变化能够真实地反映气候变化状况。在地理信息系统和遥感技术支持下,基于多源、多时相的数字遥感影像、地形图和DEM数据,并结合其他相关研究文献资料,对乌兰乌拉湖37 a来湖泊面积变化及其与自然要素(气温、降水量等)之间的关系进行了研究,并从湖泊补给的构成角度分析了其变化原因。结果表明,自1976~2012年期间,乌兰乌拉湖范围总体上有所扩张,期间经历了先萎缩、后扩张的过程。1976年乌兰乌拉湖的面积为555.97 km2,1994年其面积为496.50 km2,这期间湖泊在逐年萎缩,递减幅度为3.12 km2/a;从1998年开始,湖泊面积开始迅速扩大,1998年湖泊面积为499.83 km2,到2012年湖泊面积达655.25 km2,扩张速率为10.36 km2/a。乌兰乌拉湖水域面积变化主要集中在湖的南部河流入湖口处。1976~2012年期间,乌兰乌拉湖流域的年降水量增加,年平均气温升高。1998年以来,乌兰乌拉湖水域面积扩张的原因有二:年降水量增加;年平均气温升高导致冻融水量增加。在湖泊主要年补给水量构成中,湖面年降水量、流域年降水径流量、冻融水年补给量分别约占23.3%、43.7%和33.0%。
Plateau lakes are extremely sensitive to climate change, and changes in lakes can truly reflect the climate change. Based on the multi-source and multi-temporal digital remote sensing images, topographic maps and DEM data, combined with other relevant research literature, the change of lake area and its relation with nature under the support of GIS and remote sensing technology Elements (temperature, precipitation, etc.) were studied, and the causes of the changes were analyzed from the perspective of the composition of lake recharge. The results show that from 1976 to 2012, the range of Ulan Lake has been generally expanded, during which it experienced a process of first shrinking and then expanding. In 1976, the area of Ulan-Ula Lake was 555.97 km2, and in 1949 it was 496.50 km2. During this period, the lake shrank year by year, with a decreasing rate of 3.12 km2 / a. Since 1998, the area of the lake began to expand rapidly. In 1998, the lake area Which is 499.83 km2. By 2012, the lake area will reach 655.25 km2 with an expansion rate of 10.36 km2 / a. Wulanhu La Lake area changes are mainly concentrated in the southern lake into the lake mouth. From 1976 to 2012, the annual precipitation in the Ulan-Ula Lake basin increased and the annual average temperature increased. Since 1998, there have been two reasons for the expansion of Wulanhu lakes area: the annual precipitation has increased; the annual average temperature has increased, leading to an increase in the amount of freeze-thaw water. In the composition of the main annual supply of lakes, annual precipitation, annual runoff of watershed and annual supply of freeze-thawed water accounts for about 23.3%, 43.7% and 33.0% respectively.