哈巴湖自然保护区人工封育草原生态位研究

Study on Niche of Artificial Fencing Grassland in the Haba Lake Nature Reserve

运用Levins生态宽度指数及Pianka生态位重叠指数,对宁夏哈巴湖自然保护区人工封育草原2009年及2010年植物生态位宽度及生态位重叠进行计量。结果表明:丝叶山苦荬生态位宽度在两年中均最大,分别为0.557、0.530,是人工封育区的优势种。此外,两年间封育区其它优势种也基本相同,分别为阿尔泰狗娃花、黑沙蒿、苦豆子。两年的生态位重叠计测结果均表明,生态位宽度大的物种不一定和其它物种有大的重叠指数,即使生态位宽度较大的物种之间的重叠指数也不高。可见较大的生态位宽度和较高的生态位重叠度之间并不存在直接的线性关系;2009年、2010年较高的Pianka生态位重叠指数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。

Using Levins index and Pianka index to calculate niche breadth and niche overlap of plant in artificial fencing grassland in the Haba Lake Nature Reserve in 2009 and 2010.The results showed that the niche breadth of Ixeris chinensis（Thunb.） Nakai in 2009 and 2010 were the largest,which were 0.577 and 0.530,respectively.So,Ixeris chinensis（Thunb.） Nakai is dominant species in the artificial fencing area.Besides,other dominant species in fencing area in 2009 and 2010 were almost the same,which were Heteropappus altaicus（Willd.） Novopokr,Artemisia ordosica Krasch.and Sophora alopecuroides Linn..The results of two years niche overlap survey indicated that the species having large niche breadth didn＇t have big niche overlap index with the other species,even the niche overlap index between the species that had big niche breadth was not big,so the large niche breadth didn＇t have directly liner relation with big niche overlap;the relatively bigger niche overlap index in 2009 and 2010 all appeared between the species with small niche breadth,so it showed another viewpoint that environment and resources had high spatial heterogeneity during the process of vegetation restoration.