气候变化对白洋淀湿地的影响

生态系统对气候变化的影响和响应的敏感性研究是全球变化研究的一个重要内容。近年来，华北地区气候以暖干为主，这种趋势在一定程度上加剧了华北地区的水危机。特定的水文条件是湿地形成与维持的驱动因子，因此湿地生态系统对气候变化尤为敏感。以华北地区内陆湖泊白洋淀为研究对象，通过分析白洋淀过去40年气候、水文与生态系统发展变化过程及湿地生态与影响因子之间的相关关系，确定湿地退化的主导生态因子，探寻湿地退化的驱动机制。从而得出以下结论：1960年以来，白洋淀湿地水位降低，水量减少，面积萎缩，干淀频繁，生物多样性减少;气候变化在白洋淀湿地退化中起决定作用，其中降水对湿地的影响最大。气候变化主要通过改变湿地的水文特征，减少湿地水源补给，增加水分消耗，使湿地退化萎缩。人为因素在一定程度上加剧了这种趋势。

IMPACT OF CLIMATIC CHANGE ON BAIYANGDIAN WETLAND

The sensitiveness of ecosystems to global change is an important aspect in global change research.Global change is featured as warming and drying climate in the North China Plain in recent years,which aggravates water crisis in the region.Specific hydrological condition is a major driving factor shaping wetland and its evolvement.Wetland ecosystem is,therefore,particularly important in this region.Since 1960,the water level and volume has declined,water area has shrunk,and bio-diversity has decreased in Baiyangdian wetland.Natural factors,particularly climatic change,have played a decisive role in the process of wetland degradation;among them precipitation has significantly influenced the wetland.Climatic change has caused the variation of hydrologic characters of the wetland,the decrease of water supply,and the increase of water consumption.As a result,the wetland degraded.Human factors have intensified this trend to a certain degree.