若尔盖45年来的气候变化特征及其对当地生态环境的影响

CHARACTERISTICS OF THE CLIMATIC VARIATATION IN ZOIG■ IN THE PAST 45 YEARS AND ITS EFFECTS ON THE ECO-ENVIRONMENT IN THE AREA

草地退化、土地沙化等问题已成为若尔盖地区突出的环境问题之一.本文分析了若尔盖地区1957年以来的气候变化特征以及对当地生态环境的影响.结果表明,若尔盖地区多年平均气温呈明显升高的变化趋势,以每10年约0.23℃的倾向率增高,各季节气温也呈上升趋势,其中秋季(9～11月)和冬季(12～莅年2月)气温上升更加明显;多年平均降水量呈略有减少之势,降水倾向率为每10年减少1.75mm.其中,春季(3～5月)和秋季降水量呈现出逐年下降的趋势,秋季降水减少的趋势更明显一些,而夏季(6～8月)和冬季降水量却表现出逐年增多的趋势.受气候变暖趋干的影响,该区冻土环境和植被发生变化,土地沙化、草地严重退化等生态环境问题对当地的社会经济与环境发展产生了重要影响.

Grassland degradation and desertification have become one of the prominent environmental problems in the Zoige area. This paper analyzes the characteristics of the climatic variation from 1957 to 2001 and its influence on the eco-environment in the Zoige area. The annual average temperatures in the area showed a marked tendency of increase, with an increase rate of about 0.23 ℃ per 10 years, and the seasonal temperatures also showed a tendency of increase, which is especially the case in autumn （from September to November） and winter （from December to February） when the temperatures rose more significantly. The annual precipitation showed a slight decrease tendency, with a decrease rate of 1.75mm per years. In autumn and spring （from March to May）, the precipitation showed a tendency to decrease year by year, and more marked decrease was recorded in autumn. However, in summer （from June to August） and warming and drying winter the precipitation shows a tendency to increase year by , the frozen ground and vegetation in Zoige changed. The year. Affected by eco-environmental problems such as grassland degradation and desertification have had great effects on the social, economic and eco-environmental development in the area.