摘要
青藏高原东北部的玛曲湿地是黄河上游重要的水源涵养和补给区.为了解全球变暖背景下玛曲湿地的变化,以1990年、1994年和2001年Landsat卫星遥感影像为数据源,在遥感和地理信息系统技术支持下,基于影像光谱信息和地形高度构建的多维特征空间,采用多元统计学的逐步判别分析分类方法,对玛曲高寒沼泽湿地进行动态监测,并结合玛曲气象资料,初步分析了12 a来湿地变化的原因.结果表明:玛曲湿地面积1990年、2001年分别为1151.7 km2、1049.32 km2,其占全县土地面积从10.5%下降到9.5%,整体上呈明显萎缩之势,12 a间面积减少102.38 km2,平均年递减率为0.74%,其中1990—1994年时段年均萎缩速率为0.86%,明显快于1994-2001年时段(0.61%).气候暖干化是玛曲湿地萎缩的主要原因,而人类活动加剧了这一过程.
The Maqu wetland located in the northeast of Tibetan Plateau is an important water conserving and supplying area in the upriver regions of Yellow River. For finding out the changes of Maqu wetland under the global warming background, the wetland resources in Maqu were investigated and monitored dynamically via analyzing the Landsat-- 5/ TM and Landsat--7/ETM-k images in 1990, 1994 and 2001, using the stepwise discriminant a- nalysis of spatial--statistics, supported by RS and GIS techniques. Combining the meteorological and hydrologic data of Maqu in the corresponding period, reasons leading to the changes in the wetland were also discussed. The results indicate that the area of the Maqu wetlands was 1101.42 km^2, approximately accounting for 10.0% of total area of the county, the wetlands reduced generally by 102. 38 km2 from 1990 to 2001with a ratio of 0.74%, and the rate of reducing during 1990 to 1994 was obviously faster than that during 1994 to 2001, being 0.84% and 0.61%, respectively. Climate warming and drying should be the main reasons leading to the shrinkage of the Maqu wetland, besides the human activity pricking up the degradation.
出处
《冰川冻土》
CSCD
北大核心
2007年第6期874-881,共8页
Journal of Glaciology and Geocryology
基金
甘肃省退牧还草效益遥感监测研究项目(甘退牧200301)
科技部科研院所社会公益研究专项项目(2005DIB3J100)资助
