Objective:Ulmus lamellosa is an endemic plant in China,with a low population and a nar-row distribution range.Studying the community characteristics and ecological niche of U.lamellosa could be used to provide a theoretical basis for the protection of wild resources and the population growth of U.lamellosa.Methods:The community characteristics and niche differences of different dominant communities of U.lamellosa in Beijing were analyzed using important values,Shannon di-versity index,Margalef richness index,Levins and Shannon niche width index,and Pianka niche over-lap index.Results:The number of plant families,genera and species in the Shangfangshan I sample plot was the largest among the 4 different sites,and then were the Shangfangshan II,Xiaolongmen,and Labagoumen sample plot.For species diversity of the community,it was the largest in Shangfang-shan II sample plot,then Shangfangshan I,Xiaolongmen and Labagoumen.In the arbor layer,the niche width index of U.lamellosa was the largest in plant communities where U.lamellosa was the dominant and associated species.In the shrub layer,the niche width of U.lamellosa was higher in the plant community with U.lamellosa as the dominant species and lower in the community with U.lamel-losa as the associated species.In the dominant species community,the species pairs with larger niche overlap accounted for a larger proportion,and the species with larger niche overlap with U.lamellosa had more pairs in the associated species community than the dominant species community,and the overlap degree was larger.Conclusion:The dominant species communities of U.lamellosa had fewer species compositions and a relatively concentrated floristic distribution.In this plant community,the width of the U.lamellosa ecotone was larger and the overall degree of ecotone overlap was greater.However,fewer species overlapped with the U.lamellosa ecotone and the degree of overlap was small-er.Conversely,the U.lamellosa associated species community were on the contrary.
NETL
NSTL
万方数据
