Study On The Quantitative Ecology Of Platycladus Orientalis Community In Shanxi Huoshan

Based on the fields investigation, which selected ShanxiHuoshan characteristics of Platycladus orientalis communitieswere studied by using quantitative ecology methodology,including species composition, flora, Ward minimum varianceclustering, PCA ordination, species diversity, so that theseresults can be as theoretical basis for ecological conservation ofthis species and scientific unilization. The result showed that：(1)There were82kinds of vascular plants, belonging to33families and67genera, including ferns1family,1genus and1species, gymnosperms2family,2generas and3species,angiosperms30families64genera78species. The region ofgymnosperms and angiosperms branch number respectively thenumber of gymnosperms and angiosperms, Shanxi Province were33.33%and21.9%;The region of gymnosperm and angiospermgenera respectively gymnosperms, Shanxi Province, the numberof angiosperms is15.38%and7.97%. Shanxi biota orientaliscommunities can be divided into five families areal types, amongthem, the widespread type was the most and North temperateand South America disjunction was in the next place in the arealtypes of families.Plants in the region can be divided into14arealtypes, among them, the north temperate was the most and the widespread type was in the next place in the areal types ofgenus.(2)Classifying the23samples of community using theminimum variance clustering method. According to the principleand system classification of China vegetation, combined withthe actual situation of investigation and dominant speciesnamed community types, could be divided into six association ofPlatycladus orientalis community. Samples along the first axis,from left to right gradually from low to high elevation, showedthat the first axis represents the changes of elevation. Samplealong second axis, from top to bottom the degree of the slopeincreases gradually, suggests that the second axis wasassociated with slope, but the cumulative interpretation offormer two axis is less than50%, so the correlation of the firsttwo axis and elevation, slope of environmental factors were notvery strong.(3)Using the index of Shannon-Wiener, Simpson, speciesrichness and evenness of Platycladus orientalis community inShanxi Huoshan was studied. The result showed that,the changetrend of Shannon-Wiener index was the same as the trend ofSimpson index, increased first and then decreased andincreased and decresed again. It sames like double peak model.Species richness index overall a downward trend. The changetrend of Pielou index was the same as the trend ofShannon-Wiener and Simpson index, overall a increasing trend.(4)Comparison of three kinds of model fitting effect with AICvalue, the result showed that: cubic model fit the Shannon-Wiener index, Simpson index and Pielou index better.Simple linear regression fit the species richness index better.(5)Using Shannon-Wiener index and Levins index to measurespecies niche width showed similar results. Although somespecies in order to appear on the top, but the overall trend is thesame. Important values of species are large as well as nichebreadth are large. Niche overlap of13dominant species pairsare larger, mainly range from0.4to0.8, the proportion of nicheoverlap is the largest range from0.6to0.7, accounting for about25%of all kind of species pairs.