50年来新疆赛里木湖地区草场放牧率变化对植被演替的影响

Effects of Grazing Rate Change on Vegetation Succession in Sailimu Lake Area

利用赛里木湖地区近50年来不同时期草地调查与监测资料、实际放牧量统计资料及降水和气温资料，分析了赛里木湖北部草地植被演替受放牧率及气候变化的影响。结果显示：在放牧强度持续上升并严重超载过牧的压力下，羊茅＋杂类草的草原类草地植被成分演替趋势表现为：先是耐牧性、再生性差的杂类苹退出建群种地位，而后耐牧性和抗旱性较强的苔草成为了草地植被的亚建群种，如果放牧强度仍居高不下，苔草、百里香等耐牧性和抗旱性更强的种类将成为草地的主要建群种，羊茅种群将不断减少，甚至退出。

On the basis of the research on the gazing rate in different periods and the practical data of rainfall and the condition of climate change, the effects of gazing rate and climate change on the vegetation succession in northern Sailimu Lake Area was analysed. The results showed that the successive trend of grassland will be wholly changed. The couch grass and other weeds will be replaced. Firstly, the more durable weeds drop out and then muskeg will become the dominant vegetation. On the condition of higher gazing rate, the couch grass will be greatly reduced and furthermore, muskeg and thyme may take its place.