塔里木河下游天然植被恢复的生态学机制

在分析塔里木河下游植被退化的基础上，系统阐述了塔里木河下游植被恢复的生态学机制。封闭的内陆盆地和干旱少雨的自然环境是塔里木河下游生态系统极度脆弱的内在因素，而人为干扰是塔里木河下游植被退化的主要驱动力。塔里木河下游植被的恢复，必须遵循干旱区植物的生态学性质，密切结合植被发生所需的环境条件，特别是干旱区植被分布格局与地下水的关系。2000年5月以来的生态输水使近河道地段地下水响应明显，横向于河道一定宽度范围内植被恢复明显，但这种恢复是有限的。

Ecological Mechanism of the Natural Vegetation Restoration in the Lower Reaches of the Tarim River

In this paper, the ecological mechanism of restoration of natural vegetation in the lower reaches of the Tarim River is systemically discussed based on analyzing the natural vegetation degeneration. Substantively, the morphological pattern of the closed basin with a little precipitation and the severe natural environment are the immanent factors resulting in the extremely vulnerable ecosystems and human disturbance is the main driving factor resulting in the degeneration of natural vegetation in the lower reaches of the Tarim River. In restoring the natural vegetation in the lower reaches of the Tarim River, the ecological properties of vegetation in arid areas must be followed by combining the environmental conditions suiting plat growth, especially the relationship between vegetation growth and groundwater level. The response of groundwater level to transfusing stream water to the lower reaches of the Tarim River for the ecology since May 2000 is sensitive, and the vegetation in a certain extent along both riversides has been obviously regenerated, such regeneration, however, is limited. Therefore, it is suggested to develop the environmental monitoring system, enhance the management of the natural vegetation in the lower reaches of the Tarim River and of water resources in the Tarim River Watershed, regulating the structure of crop growing, and spread the water-saving farming in the watershed.