摘要
黑河下游地区近年来由于河水注入量的持续减少,使得依赖河水补给的地下水相应减少,造成区域性地下水位下降,从而出现了一系列的生态环境问题.大面积湿地消失,天然植被全面衰败,土地盐化加剧,胡杨和沙枣林面积减少,并以老林为主.红柳灌丛也减少,并且多已成为稀疏矮化的群落.各种禾草草甸严重退化,多以演替成苦豆子群落.为了恢复和重建受损的下游生态系统,2 0 0 0年7月开始,实施了黑河下游应急生态输水工程,水流于2 0 0 2年7月17日流进黑河尾闾端的东、西居延海,使干涸10年的居延海重新受到水的滋润.作者根据近三年黑河下游分水前后地下水位和植被等项内容的监测资料,探讨了地下水位与天然植被生长的相互关系.研究结果表明:分水使得该地区生态环境有了较大的改善,地下水位普遍抬升;胡杨林得到恢复;灌木荒漠植被得到部分恢复;
In recent years, the discharge of water has continuously declined in the lower reaches of the Heihe River thereby resulting in the reduction of groundwater-replenishing water from the river, which cause the water table to go down and thus resulted a series of environmental problems. The wetland area has varnished in great quantity, the natural vegetations have fully degenerated, the land salinization has become intensified, and Populus euphratica and Elaeagnus angustifolia areas, which are mainly occupied by the over matured forests, have decreased. Tamarix ramosissima shrubberies has decreased in number so as to become sparsely distributed and dwarfed communities. The meadows consisting of various cereal grasses have severely degenerated and mainly succeed into Sophora alopecuroides communities. The emergency project of water import to the lower reaches of the Heihe River started in July 2000 on purpose of rehabilitating and constructing the ecosystems in the lower reaches of the river, and water inported by the project flowed into the West and East Juyanhai lakes on July 17,2002 located at the lower end of the Heihe River thus making the 10 year dryness of the lakes winded up. The paper explores the relations between water table and vegetation growth on the basis of watertable and vegetation data about the lower reaches of the Heihe River obtained in the monitoring of the river during three years fore and aft its water import. Its results indicate that its water import has improved the environment of the area in question, raised the water table, recovered Populus euphratica forests, partially recovered desert shrubberies, and regenerated meadow grasses to some extent.
出处
《西北植物学报》
CAS
CSCD
北大核心
2005年第4期631-640,共10页
Acta Botanica Boreali-Occidentalia Sinica
基金
中国科学院引进杰出人才课题 2 0 0 3 40 1
中国科学院知识创新工程项目 KZCX1-0 9-0 3
国家重点基础研究发展规划项目 G19990 42 3 0 60 1 资助
关键词
黑河下游
分水
天然植被
地下水位
lower reaches of the Heihe River
water import
natural vegetations
water table
