人类活动对乌梁素海湿地环境演变的影响分析

The impacts of human activities on the Wuliangsuhai wetland environment

乌梁素海是我国半荒漠地区具有很高生态价值和社会效益的大型多功能湖泊湿地,是黄河流域最大的淡水湖泊,也是内蒙古河套灌区唯一的承泄途径．乌梁素海的补给水源主要包括含高N,P的农田退水,工业废水以及生活污水,这些退水及废污水的排入使得湿地环境发生着重大的变化．本文在收集1986-2004年19年间Landsat TM/ETM遥感影像数据的基础上,结合乌梁素海历史资料,分析了80年代以来人类活动对湿地环境的影响,这种影响主要体现在人工芦苇面积不断扩大,富营养化程度逐年增高,水生资源迅速减少等方面,尽管2003年以来“引黄入海”工程的实施某种程度上缓解了湿地环境恶化的进程,但湿地环境仍然面临严重的威胁．

Wuliangsuhai is the large-scaled multi-function lake-wetland with high ecological and social value in the semi-desert area of China , the biggest freshwater lake in the Yellow River basin, and also the unique carrying and drainage way to the Hetao irrigation area. The major recharge sources of Wuliangsuhai wetland are irrigation return with high-density nitrogen and phosphorus, industrial wastewater and sewage. On the basis of Landsat TM or ETM data of 19 years from 1986 to 2004,integrating with historical materials, the impacts of human activities on the wetland water environment were analyzed. These impacts mainly include the increase of artificial reeds area and dense water weed area, the deterioration of water environment, the rising of lake eutrophication, and the reduction of aquatic resources. Though the applications of the project diverting water from Yellow River to Wuliangsuhai wet- land slow down the process of the deterioration of the wetland environment, the Wuliangsuhai wetland still confronts with serious threat.