中国特有植物短丝木犀(Osmanthus serrulatus Rehd.)群落结构及其环境解释

为了解环境因子对短丝木犀植物群落的影响,研究了四川省宝兴县东拉山短丝木犀植物群落地区的环境因子、TWINSPAN分类、物种和多样性指数与环境因子的DCCA排序。结果表明:1)TWINSPAN将东拉山短丝木犀24个植物群落里划分为12个群落类型,分类结果在空间上反映了东拉山植物群落的演替变化趋势。2)短丝木犀植物群落生长在土壤含水量较高、郁闭度较高,并处于西南和南坡向的沟边。短丝木犀群落的主要伴生物种为鹅耳枥Carpinus turczaninowii、宝兴木姜子Litsea moupinensis、领春木Euptelea pleiosperma、云锦杜鹃Rhododendron fortunei、宝兴过路黄Lysimachia baoxingensis、糙苏Phlomis umbrosa和铁角蕨Asplenium trichomanes。3)DCCA排序结果验证了TWINSPAN分类结果的合理性,同时指出影响东拉山短丝木犀植物群落类型及空间分布的重要环境因子是土壤有机质和腐殖质含量。

Analysis of community structure of Osmanthus serrulatus based on TWINSPAN classification and DCCA sequencing

Plant community classification and ordination categorizes plant communities according to characteristics or attributes, and is an important means of analyzing the ecological relationship between vegetation and the environment. This is the most basic, but complicated research content in vegetation ecology. The western Sichuan region is dominated by mountainous and plateau geomorphology. The complex and unique natural and geographical condition of this area results in an abundance of plant species. However, they are exceedingly difficult to classify because of complex environmental conditions and the rich number of species. To understand the effect of environmental factors on the Osmanthus serrulatus plant community, this study investigated the environmental factors, TWINSPAN classification, species and diversity index, and environmental factors of Detrended Canonical Correspondence Analysis (DCCA) in the community region of Osmanthus serrulatus in the Dongla Mountain, Baoxing County, Sichuan Province. Because the DCCA ordination axe for clustering and classification combines vegetation and environmental factors, it can properly express the environmental and structural gradient of the plant community, which reflects the spatial variation of the environment and its structure. In this study, the classification and ordination of the Osmanthus serrulatus community in western Sichuan mountain regions was performed in order to lay a foundation for further analysis of the biodiversity pattern and maintenance mechanism of the fragmented and crushed habitat of the Osmanthus serrulatus community. The results showed that:1) 24 community plots were divided into 12 coenotypes by TWINSPAN, which revealed the community successional trend in space. 2) Osmanthus serrulatus were distributed in the southwest and south slopes of the ditch, which had higher soil moisture levels and canopy densities, and coexisted with Carpinus turczaninowii, Litsea moupinensis, Euptelea pleiosperma, Rhododendron fortunei, Lysimachia baoxingensis, Phlomis umbrosa, and Asplenium trichomanes. 3) The DCCA ordination results verified the rationality of the TWINSPAN classification, and indicated that the organic and humus content were mainly environmental factors which influenced the Osmanthus serrulatus plant community type and spatial distribution.