不同沙化高寒草地植物群落结构特征及土壤理化特性研究

Studyon plant communitystructure and soil physical and chemical characteristics in different desertification Alpine Steppe

以青海省治多县轻度沙化和重度沙化草地为研究对象,对其植被群落特征和土壤理化性状进行了调查。结果表明：随着草地沙化程度的加剧,草地植物群落结构（如群落优势种等）发生了明显的变化,群落盖度、生物量均明显下降（P〈0.01）,植被高度反而上升（P〈0.01）。而通过保护与综合治理,重度沙化草地物种数、多样性指数、均匀性指数却大于轻度沙化草地。同时,随着草地沙化程度的加剧,土壤养分在0~15cm水平上明显下降（P〈0.01）,而在15~30cm水平上变化不明显。

Structure characteristics of plant community and soil physical and chemical properties were investigated in mild desertificated and severe desertificated grassland of Zhiduo County.The result showed that the dominant species in vegetation community had significantly changed with the increase of desertification,the cover and aboveground biomass decreased with the increase of desertification（P〈0.01）,however,the plant height increased.The species number,diversity index and the evenness index in severe desertificated grassland were higher than that of light desertificated grassland.Meanwhile,the soil nutrient at the 0~15cm significantly decreased with increase of grassland desertification（P〈0.01）,while it did not obviously changed at 15~30cm.