摘要
由于近 5 0年来人类不合理的水土资源和生物资源的开发利用 ,导致塔里木河下游的生态环境问题日趋严峻。特别是 1 972年大西海子水库建成后 ,其下 32 1km河道全部断流、台特玛湖干枯、地下水位大幅度下降 ,由地下水维系的植被群落出现严重退化。为此 ,新疆人民政府于 2 0 0 0年 5月实施了旨在挽救当地生态环境的塔里木河下游应急生态输水工程。输水后地下水位大幅升高 ,相应地 ,植被对水的响应也是非常明显 ,随着第一次放水 ,沿河岸许多草本植被得以重新萌发 ,而一些耐干旱的乔灌木随着生境的改变 ,长势也出现明显的好转 ,主要表现在植被盖度、胡杨冠幅、植被多样性指数和植被丰富度指数的提高。为此 ,本文采用模糊聚类法对塔里木河下游输水后的响应范围进行分析 ,发现输水后受输水影响显著的距离为 1 5 0m ,中度影响的距离为 35 0m ,轻度影响的距离为 70 0m ,而 70 0m以外基本不受生态输水的影响。
Due to the overuse of water resources, over-reclamation land and over-grazing or unrestricted cutting natural resources in recent 50 years, many environment problems appeard in the lower reaches of Tarim River. Especially when the Daxihaizi reservoir was built in 1972, river was cut by 320km, groundwater was decreased, desert vegetation was seriously degenerated, natural Populus euphratica was reduced by large area, biology diversity was suffered. In order to resume ecosystem of lower reaches of Tarim River, protect 'Green corridor' and the 218 th national highway, the project of transport water to lower reaches of Tarim River was carried out from May, 2000. It lasted 325 days and transported 6.9×108 m3 water to the low watercourse which broken about 30 years. The groundwater level、surface ecology processes were changed obviously. According to the monitoring and analysis in this region, many extremely declared vegetations have been restored. The main reflect in the groundwater level, vegetation coverage, diversity of biology and the species richness all increased. In this paper, based on the Fuzzy theory, adopted the method of Fuzzy clustering analysis, we analysed the influence range and intensity, and the respond of surface ecology process by transporting water. The result showed that the sensitive area was about 150m, the middle sensitive area is 350m, the light sensitive area is 700m, the respond is inconspicuous when the distance beyond 700m.
出处
《干旱区资源与环境》
CSSCI
CSCD
2004年第1期54-58,共5页
Journal of Arid Land Resources and Environment
基金
国家重点基础研究规划项目 (G19990 43 5 0 6)
中国科学院知识创新项目 (KZCX1-0 8-0 3 -0 2 )资助
关键词
塔里木河下游
生态输水
模糊聚类
生态环境
响应范围
Ecology processes after transporting water
lower reaches of Tarim River
Fuzzy clustering
respond range
