Abstract:Using meteorological data, water area and water level data, and ecological data in the Hulun Lake area, we analyzed influences of regional climate change to wetland ecosystem evolvement of the Hulun Lake area. Regression analyses shows (1)climate change presented a warmer and dryer trend during last 45 years that might be the major cause of water resources deficit and ecosystem degradation; (2) water area and level indicated a consistent trend with an average changing rate of 34.78km2/10a and 0.27m/10a, concretely, slowly increase during 1959-1963 and 1983-1991, decrease during 1964-1982 and 1992-2006 with maximum decrease from 2000 to 2006; (3)a positive correlation was detected between water area/level and precipitation with a changing rate of 2-19 km2 increases of water area per 10mm increase in seasonal and annual precipitation,whereas negative correlations were found between water area/level and air temperature and evaporation, respectively, with a changing rate of 28-80km2 and 4cm decreases of water area and water level per 1℃ increase in seasonal and annual temperature; (4) induced by warmer and dryer climate, the desertification area increased to over 100km2，degradation area of pasture accounted for 30% of the total area, the vegetation coverage decreased 15%-25% since 1974, and the primary production decreased 30%-50% and less than 20% in the most severe area.