三江源玛珂河林区寒温性针叶林优势草本种间联结研究

Interspecific association of dominant herbaceous species in cold temperate coniferous forest of Ma Kehe Forest Region in San Jiangyuan,northwestern China

三江源自然保护区玛珂河林区的草本植物对寒温性针叶林的早期演替和生态恢复有着十分重要的影响。该文通过χ2统计量检测、共同出现百分率和联结系数方法,对40块寒温性针叶林样地中的22种优势草本的种间联结性进行定量分析,结果表明:231对优势草本组合中,有118对呈现正联结,其中有8对呈极显著正联结(P<0.01),6对呈显著正联结(P<0.05);负联结有112对,仅有2对优势草本物种呈显著负联结(P<0.05);完全独立的有1对。可见,玛珂河林区寒温性针叶林中,超过一半的草本物种的生态学和生物学特性相似,表现为正联结,并且未达到显著水平;同时也有接近一半的优势草本物种之间竞争有限的环境资源而产生竞争和排斥。

Ma Kehe Forest Region is one of the core areas in San Jiangyuan National Nature Reserve. A large number of herbaceous species distribute in the cold temperate coniferous forest region, and they play important role in the process of earlier succession and ecological restoration of the cold temperate coniferous forests. A series of techniques, including related tests, calculation of the percentage of co-occurrence and association coefficient, had been used to analyze the interspecific association among 22 dominant herbaceous species in 40 plots in Ma Kehe Forest Region. The results showed that over half of dominant herbaceous species could appear in the same community and presented positive interspecific association, but the degree of positive association was very weak, 118 pairs of species showed their positive correlation and 112 pairs of species showed their negative correlation in 231 pairs of herbaceous species, only one pair of species was of absolute independent correlation. So over half of dominant herbaceous species were positive interspecific association, and most of them had opportunity to use the same resources and occupy similar niche in the same community,but there was almost no significance interspecific associations; near half of dominant herbaceous species were negative interspecific association due to their competitions in Ma Kehe Forest Region.