Factor And Relationship With The Ecological Diversity Of Plant Species Wudalianchi Volcano

We studied the relationships of plant diversity, slopes, altitudes and soil environment factors by correlation analysis in different historical period volcanoes of Wudaliangchi through the canonical correspondence analysis and stepwise regression analysis methods. The results shown:(1) The a diversity index was lowest in new period of Laoheshan volcano and taken on the trend that increase firstly and then decrease according with historical period, but the index was biggest in the middle period of Dongjiaodebu volcano through studying the plant community diversity during three different historical period volcanoes.For the a diversity index of shrub layer, it was lowest in the new period of Laoheshan volcano and has a trend that increase firstly and then stable according with historical period, but it was biggest in the middle period of Dongjiaodebu volcano. For the different slopes of herb layers, the a diversity index was lowest in the new period of Laoheshan volcano and taken on the trend that increase and then stable in the middle and later periods according with historical period. For the different slopes and the plant community, the variation characteristics of a diversity index, the community simpsons index and Shannon-winener index, evenness and richness indexes were all lowest in the new period volcano and biggest in the middle period, and then decreased gradually, Which conformed to the intermediate disturbance hypothesis.(2) Through studying the β community diversity during three different historical period volcanoes, the Jaccard indexed were lowest in Laoheishan and Dongjiaodebu volcanoes which erupted before290and80million years, respectively, this illustrate that the number species the two volcanos owned were less, and show that the huge variation between new period volcano sparse vegetation and middle period broadleaved deciduous forest. However, the Cody index was large from Laoheishan to Dongjiadebu volcanos, show that the plant evolution rate was large and community richness increase, this conformed to the richness index’s trends significant increase from Laoheishan to Dongjiadebu volcanos.(3) Through studying the south and north slopes during three different historical period volcanoes, the tree layer and shrub layer’s diversity for north slope were larger then south slope, however, the index of herb was opposite. The variation trend of plant community has the same trend with tree layer and shrub layer, which illustrate that the slopes has close relationship with plant community diversity for different period volcanoes. (4) From the plant diverisity variation under different slopes and historical periods, it can conclude that the diversity rules of different period and each slope were not obvious alone the altitude, showing that the altitude was not the main factor influenced this area diversity.(5) Through studying the relationship between plant community and soil environment factors in different historical periods volcanos, correlation analysis shown that the main soil factors influence the plant community diversity fo volcano were soil pH and available nitrogen.