Study On Quantitative Ecology Of Cotinus Coggygria Communities In Shanxi

This article, regarding the Shanxi Cotinus coggygria communitiesas the research object, through the research of communities andenvironment factor investigation, analyzes the main feature ofCotinus coggygria communitiesin Shanxi, including the study ofspecies composition, flora and life form spectra, and TWINSPANclassification, species diversity, biomass and so on, attaining therelationship between Cotinus coggygria communities andenvironmental factors. The results show that:（1） There are totally 158 species of vascular plants in researchplant communities, belonging to 87 families and 113 genera, amongwhich there is one species of Pteridophyte in family 1, genera 1;3species of Gymnosperm in families 2, genera 2;138 species ofDicotyledonous in families 79, genera 95; 16 species ofMonocotyledonous in families 5, genera 15. Composite, Rosaceae,Leguminosae, Gramineae, Liliaceae, Labiatae, Betulaceae,Ranunculaceae, Oleacea, Umbelliferae are the dominant family, thenumber of genera in these branch are accounted for 59.29% of totalgenera of seed plants, which in the studied region plant communitiesonly accounts for 11.49% of the numerous number. The flora of north temperate zone is dorminant in Shanxi Cotinus coggygria community.It has 13 types of distribution zones and 7 variants. Temperateproperties are obvious, and north temperate distribution is the basicattribute. The north temperate zone accounts for 23.13% of totalgenera, followed by the world distribution type （11.50%）, old Worldtropics type （9.73%） and a pantropical distribution type （7.08%）.（2）The biological spectrum in Shanxi Cotinus coggygriacommunities abounds in phanerophytes, accounting for about 30% ofthe total, phanerophytes can be divided into mesophanerophytes andmicrophanerophytes about 2 15m and nanophanerophytes at theheight of less than 2m. The second is chamaephytes andhemicryptophytes, accounting for 27.85%and 24.68%, cryptophyteand therophytes are less, only 6.33% and10.76%.（3）By TWINSPAN, all of the 65 samples were divided into 8associations. The result of 65 samples DCA ordination show that themain factors restricting Cotinus coggygria communitiestypedistribution are altitude and the humidity. Seeing from the Cotinuscoggygria association type, each association type is in a sort ofregular distribution. The results of ranking the 19 dominant speciesin the DCA are revealed by environmental gradients. In general, thedistribution pattern of dominant species decides sssociationdistribution pattern.（4）By making diversity analysis of the communities in Shanxi ofCotinus coggygria according to the 5 diversity index of R₀, H, E_h, x, Ep,the results can be made that species diversity index is influenced byboth species richness and evenness index. The richness index anddiversity index in Shanxi Cotinus coggygria communities change obviously, which shows the distribution of Cotinus coggygria speciesis obviously inhomogeneous, and communities composition,structure and characteristics are significantly different. For themajority of plant communitiesspecies, the richness index of herblayer is higher than layer, but for some communities, richness indexshowed shrub layer > herb layer, because of the poor site conditions,the degree of human disturbance or higher coverage of the shrublayer are relatively abundant.（5）By researching the common Cotinus coggygriacommunitiesbiomass, it can be found that in four kind of shrubbiomass types based on the biomass size, the order is size, Ass.Cotinus coggygria - Carex lanceolata > Ass. Cotinus coggygria+ Rosaxanthina - Carex lanceolata > Ass. Cotinus coggygria+ Ostryopsisdavidiana - Carex lanceolata > Ass. Cotinus coggygria + Quercuswutaishanica - Carex lanceolata + Lespedeza davurica. In the fourkinds of shrub types, the biomass of a plant on the ground accountsfor different percentage, but the proportions are all above 90%, whichshows shrub biomass is the key to the shrub aboveground biomassand its function is the most obvious in the those communities. theshrub layer plays an important role in maintenaning communitiesstability and resisting external interference.