湛江市半自然植物群落乔木层主要优势种生态位及种间联结性

Niche and Interspecific Connectivity of Dominant Species in the Arbor Layer of Semi-Natural Plant Communities in Zhanjiang City

研究种群生态位及种间联结,探索种间共生关系,对半自然植物群落的稳定发展与城市公园建设具有重要的意义。采用生态位指数测定、方差比率法、χ~2检验及空间格局分析法,对湛江市城市半自然植物群落乔木层主要优势种生态位及种间联结进行了分析。结果表明:小叶榕(Ficus concinna)、散尾葵(hrysalidocarpus lutescens)及鸡冠刺桐(Erythrina crista-galli)等物种生态位宽度值较大,对环境资源有较强的利用能力;190个种对生态位重叠程度较低,53.16%的种对生态位未重叠,种间竞争关系弱;乔木层主要物种的总体联结性表现为不显著正联结(P>0.05),χ~2检验结果表明,负联结数量多于正联结,且全部种对联结程度均不显著。指学湛江市半自然植物群落乔木层物种在平面上均为聚集分布,但物种间相互作用弱,尚处于群落演替的前期阶段。

Studying niche and inter-specific association provides vital oretical for steady development of semi-natural plant communities and the construction of urban parks.Niche index determination,variance ratio method,χ~2 test and spatial pattern analysis method were used to analyze the niches and interspecific associations of main dominant species in the arbor layer of urban semi-natural plant communities in Zhanjiang City.The results showed that:Ficus concinna,hrysalidocarpus lutescens and Erythrina crista-galli et al.showed the strong utilization ability to the environmental resources such as the largest niche breadth among dominant species.The 190 species pairs had a low degree of niche overlap,53.16% of the species pairs did not overlap,and the interspecific competition relationship was weak.The VR and w test showed that the overall inter-specific associations were not significantly positive associations among the main species in the tree layer.The results of χ~2 test showed that the significance ratios of the species pairs were all lower.In general,most of the species showed an clumped distribution pattern,but the interaction between species is weak and the communities are still under early stage of succession.