宁夏盐池人工封育草原植物生态位研究

Vegetable niche of enclosed grassland in Yanchi county of Ningxia

为了解干旱半干旱区草原植物生态位格局,运用Levins生态宽度指数及Pianka生态位重叠指数,对宁夏盐池人工封育草原2002年及2003年植物生态位宽度及生态位重叠进行计量。结果表明:茵陈蒿的生物、生态学特性决定了它在该区的优势地位,2002年、2003年其生态位宽度远远高于其他物种(0.758和0.868),并且继续保持上升趋势;2002年及2003的生态位重叠结果均表明,生态位宽度大的物种不一定和其他物种有大的重叠值,较高的生态位宽度和较高的生态位重叠之间并不存在直接的线性关系;2002年、2003年较高的Pianka生态位重叠值都出现在生态位宽度较小的物种之间。这一现象从另外一个角度说明植被恢复过程中环境资源存在着高度的空间异质性。

In order to find the vegetable niche pattern in arid and semi-arid grassland region, breadth and niche overlapping in Yanchi county of Nixia in 2002 and 2003 are measured by means the niche of Levins niche breadth and Pianka niche overlapping indexes of enclosed grassland. The results showed that, the biological and ecological characteristics of Artemisia capillaris Thunb determined its predominant station in this region, and its niche breadth in 2002 and 2003 were bigger than other species （0.758 and 0. 868） continuing to keep rising trend. The results of niche overlapping in 2002 and 2003 also showed that the species with big niche breadth didn＇t always have big niche overlapping, and the niche breadth and niche overlapping did not have a positive direct linear relation. The higher Pianka niche overlapping in 2002 and 2003 both appeared in the species with low niche breadth, which showed from another point of view that environment and resources have high spatial heterogeneity during the vegetation restoration process.