摘要
近年来,由于气候条件的变化,青海湖水位呈下降趋势,水域面积逐年缩小。选用1986年至2005 年的美国Landsat-5卫星图像数据对青海湖地区进行长达20年的跟踪监测研究结果表明,2004年青海湖水域面积比1986年缩小了约80 km2,与1989年相比,水域面积缩小了129 km2;水域面积最大和最小的年份分别是 1989年和2001年,面积相差135 km2。在过去20年间,青海湖水域面积的变化有2个明显的特征,第一,整体上呈现出十分明显的下降趋势;第二,年度变化呈现了在整体下降的同时又有短期小幅回升的现象,回升时间不超过2年。湖岸线年度变化遥感监测资料表明,青海湖湖岸线的年度推进量在40-200 m之间。在与青海省及湖区同期气象资料的分析对比后发现,湖区水域面积与地表蒸发量、气温以及地表温度的年度变化呈负相关, 且变化的趋势有较好的一致性。
The water level of Qinghai Lake descends and its water area reduces in recent years owing to the climate changing. In this paper, the remote sensing methods and Landsat - 5 image data from 1986 to 2005 were used for monitoring study on Qinghai Lake. It shows that, the water area in 2004 reduced about 80 km^2 than that in 1986 and 129 km^2 than that in 1989. The maximum and minimum water area appeared in 1989 and 2001 respectively, and the difference between them is 135 km^2. Studies show that there are two apparent features in the annual changing of the water area of Qinghai Lake: (1)The water level shows an obvious descending tendency in the last 20 years. (2)The annual changing of water level shows a decline on the whole and at the same time shows a small amplitude of ascending during a short period which is less than 2 years. Remote sensing studies also show that the annual lakeshore changing of Qinghai Lake is about 40 m to 200 m. Analysis on the climate data of the same time shows that there is a negative relation between the water area of the lake and the changes of the surface evaporating amount, temperature and surface temperature and their changing tendencies have a better coincidence.
出处
《古地理学报》
CAS
CSCD
2006年第1期131-141,共11页
Journal of Palaeogeography:Chinese Edition
关键词
青海湖
水域面积
湖岸变化
遥感监测
变化趋势
Qinghai Lake, water area, lakeshore changing, remote sensing monitoring, changing tendency