若尔盖气候变化及其对湿地退化的影响

Climate Change in Zoigê Plateau Marsh Wetland and Its Impact on Wetland Degradation

若尔盖高原沼泽湿地地处黄河上游,属江河源区,其生态作用对黄河的安危有直接影响,近年来退化严重。本文利用若尔盖高原湿地周边4个气象站1971—2000年逐月平均气温和降水量资料,分析了年和四季的气候特征及气候变化趋势,并对气候突变进行了检验。结果表明:近30年来若尔盖湿地表现出气温升高、降水量减少、蒸发量增大的暖干化趋势,并且在20世纪90年代后期变化趋势更加明显。这种气候变化趋势使得若尔盖高原湿地的地表水资源减少,湿地萎缩,加速了草地退化和沙化。在气候暖干化的背景下,人类活动又加剧了若尔盖高原沼泽湿地萎缩及退化趋势。

Zoigê Plateau Marsh Wetland is in up-reach of the Yellow River, and is the source of the River. The wetland degradation is serious in this area in recent years. Using the air temperature and precipitation data at 4 meteorological stations in the Zoigê Plateau Marsh Wetland region from 1971 to 2000, the climatic characters, the climatic variation tendencies and their abrupt changes are analyzed in this paper. The result shows that the annual mean evaporation and air temperature have been rised and precipitation has been decreased over the Region in recent 30 years and the tendency of transiting toward warm and dry was very obvious since the 1990r s. The climatic warming causes water resources reducing, shrinking of wetland in this area, which speeds up trend of grassland degeneration and desertification. Human activity interference is also responsible for retrogression of the Zoigê Plateau Marsh Wetland and has a severe impact on ecological environment under this climatic tendency.