近40a岱海湖面动态变化研究

Research on the area change processes in the past 40a of Daihai Lake

文中以位于干旱-半干旱过渡区的岱海为研究对象,利用地形图和13期Landsat遥感影像,通过人工目视解译方法提取岱海水域面积和流域耕地面积,探讨其最近40a内时空变化过程及机制。结果表明:从1976年的149.55km^2萎缩到2015年的60.54km^2,缩减幅度达到59.52%。其中1995-2000年湖面萎缩最显著,缩减面积达到18.76km^2,2000-2006年湖面萎缩了5.01km^2,2010-2015年间又缩减了8.85km^2。从湖泊面积变化过程分析发现,其面积变化主要受人类活动以及气候暖干化等因素的共同影响。自1976-2015年间气温升幅明显,降水量和蒸发量呈减少趋势,入湖径流量减少明显。随流域人口迅速增长导致流域工农业总用水量快速增加,对湖泊面积变化形成巨大影响。

Daihai Lake which is located in the arid and semi-arid transition region,was chosen as the research object,topographic map and 13 remote sensing images,and visual interpretation method were applied to extract the Daihai Lakes area. Changing process and the reasons for lake-level fluctuation in 40 a were discussed. The result showed that the lake area had been gradually shrinking from 149. 55km^2 in 1976 to 60. 54km^2 in 2015,with the contraction pace of 59. 52%. Shrinking area was 18. 76km^2 in the period of 1995-2000,5. 01km^2in2000-2006,8. 85km^2 in 2010-2015. Temperature increased significantly,precipitation and evaporation showed a decreasing trend and lake runoff decreased obviously from 1976 to 2015. With the rapid increase of the population in the basin,the total amount of water in the basin was also rapidly increasing,which had a great influence on the change of the lake area.