The Effection Of Chlimate Change To The Desertification Of Ruoergai Wetland

The ecological environment of Ruoergai wetland was becoming more and more serious in recent years. The swamp water decreased and the desert areas increased The desert area didn’t have magnificently increased since1995.The paper researched the effect of climate change especially the combination of thermal and water factors to the progress the desertification. We used the annual meteorological data of temperature, precipitation and evaporation in Ruoergai from1957to2004, analyzing the annual and seasonal change of the climate. A new index which was the total of frequency of different ranks of thermal and water factors was established to analyze the climate change. The ranks of the meteorological factors was divided according to their own numbers. Besides, the desert data during48years was divided into4stages according to the character of desertification speed. We chose the dominant plants’growing stage as the annual research time and calculated the frequency of thermal and water factors in the research time of4stages.The result displays that the temperature and the evaporation increased, but the precipitation decreased at the same time. The temperature in four seasons all increased and the range of rise in the winter was the most significant with the trend rate of0.04℃/10a.The precipitation of spring and autumn decreased while it increased in summer and winter. The range of drop in the autumn was the most significant with the trend rate of-0.48mm/10a and the most significant rise was7.5mm/10a,which was in the winter. The total frequency of the combination for thermal and water factors reduced obviously from1970and it was in the downward trend. At the same time, the distribution of the frequency developed to the high temperature area. The climate became warm and dry in the Ruoergai wetland,promoting the desertification of the wetland. The research also displayed that the climate of the wetland area had became warm and dry since80th but the desert area didn’t increased obviously. Until1995the desert area didn’t have shapely rinsed. The research explained that the change of the combination for thermal and water factors didn’t have obvious influence on the desertification of the same period.