Abstract:

The interspecific associations of communities between different slope aspects and positions in the north slope of Tianshan Mountains were analyzed using variance tests, χ² test with 2×2 contingency table and Spearman's rank correlation coefficient. Correlations between these species were determined by Ochiai indices. The results indicated that slope aspect and position had no significant effect on Achnatherum inebrians communities, the associations of the plant species in the communities were significant negative, and the community succession was instable. Except the lower part of sunny slope, a few species had significant correlation. OI value displayed that there was no correlation between species in gully bottom and sunny slopes, whereas there was strong negative correlations in shady slopes. Interspecific association between Achnatherum inebrians and most of other plant species in the communities was negative and had high association degree.

Key words: Achnatherum inebrians communities, Aspect of slope, Position of slope, Interspecific association, Community succession

摘要：

运用方差比率法、基于2×2列联表的χ²检验以及Spearman秩相关系数对天山北坡不同坡位和坡向的醉马草(Achnatherum inebrians)群落进行总体联结性和种对间的联结性分析,同时利用Ochiai指数测定各种对间的关联程度.结果表明:坡位及坡向对醉马草群落总体关联性无影响,各样地上群落主要植物种间总体表现为显著负相关,群落处在不稳定发展阶段;坡位及坡向对群落成对物种间的关联性影响较小,除了阳坡下段极显著、显著相关的种对数较多外,其他样地上极显著、显著相关的种对数都较少,所占比例很低.成对物种关联程度受坡向而不受坡位的影响,OI值显示沟底、阳坡主要物种间负联结关系松散,物种比较独立,阴坡负联结关系较强;所有样地上醉马草与大多数物种表现为负关联且具有较高的关联度.

关键词: 醉马草群落, 坡位, 坡向, 种间联结, 群落演替