气候变化对黄河首曲地区草地生态退化的影响  

The Causes of Grassland Degradation and Corresponding Prevention Strategies:A Case Study in Maqu County

作　　者：姚玉璧[1] 王润元[1] 尹东[1] 邓振镛[1] 张秀云 李侠[3] 

机构地区：[1]中国气象局兰州干旱气象研究所甘肃省干旱气候变化与减灾重点实验室 [2]甘肃省定西市气象局,定西743000 [3]甘肃省天水市气象局,天水741000

出　　处：《资源科学》2007年第4期127-133,共7页Resources Science

基　　金：中国气象局成都高原气象研究所高原气象开放基金项目(编号:LPM2006014);科技部科研院所社会公益研究专项(编号:2005DIB3J100);甘肃省科学技术攻关计划项目(编号:ZGS042-A44-017)

摘　　要：黄河在甘肃玛曲县境内形成了一个长433km“U”字形的第一弯,这里拥有大面积亚高山草甸类草场和沼泽湿地,被誉为亚洲最好的牧场之一,但是,近50年来黄河首曲草地生态逆向演替,草场退化、沙化,水土流失,生物多样性减少,生态功能弱化。利用黄河首曲玛曲县草地与湿地气候资料和生态观测资料及统计资料,分析研究表明:造成生态环境退化的主要原因是气候变化和环境蠕变。玛曲县降水量年际变化呈下降趋势,气温年际变化趋势呈上升趋势,增温速度均大于全国增温速度。草地年干燥指数呈显著上升趋势,20世纪80年代末至2004年明显趋于干旱化,气候变化是草地生态退化的自然诱发因素,而超载过牧,滥采乱挖,人为破坏,生物链失衡等环境蠕变是造成生态退化的人为因素,二者共同作用导致黄河首曲草地生态环境退化。为此,提出了适应高原草地生态环境演替规律的生态环境保护对策。Yellow river presents its first meander of 433 kilometer ＂U＂ deltoid in Maqu County of Gansu province. Grass land of sub-alp meadow and swamp over there was the best one in Asia ever before. In the last 50 years, however, due to the reverse succession of grassland ecology, grassland in the region has been degrading, and water and soil have been losing. Biodiversity of have been decreased and ecological function have been weakening. This paper analyzed the climate data, the grassland and wetland ecological data in Maqu County. The result showed that the main causes of ecological degeneration are climatic change. It is found that precipitation presented a descending trend, with a rate of - 13.70mm per 10 years. It is proved that the 2 - 4 years short period and 11 - 12 years long period are significant. The results also show that the annual changes of temperature display a significant ascending trend, with a rising rate of 0. 044 ℃ per 10 years, which is higher than the average rising rate of the country. It is proved that aridity index of grassland display ascending trend, with a rising rate of 0.114 per 10 years, and the tendency is significant from the end of 1980 to 2004 year. Climate change is natural factors inducing grassland ecology degeneration. Moreover, such artificial factors as over raising, excessive harvest, and activities destroying the biological chain are other driver force to induce grassland ecological degeneration.

关 键 词：草地生态退化 气候变化 环境蠕变 玛曲县 

分 类 号：S812.6[农业科学—草业科学]