Analysis On The Relationship Between Vegetation And Environment In Southern Shanxi

The plant communities in Southern Shanxi were studied by quantitative ecology methods on the basis of investigation dataset from the field, involving community classification and ordination, species diversity and plant functional groups(PFGs).The purposes of this study were to explore a comprehensive understanding ofvegetation structure and function in Southern Shanxi, reveal the impacts and interrelations between communities and environment, and present scientific basis for the local biodiversity conservation, vegetation restoration and management.The plant communities in Southern Shanxi were classified into 12 forest associations,9 shrub associations and 8 herb associations by TWINSPAN. The results of DCA ordination of plots and species for the three community types were as follows:(1) In the forest communities, the DCA ordination axis 1 showed that plant communities changed along slope gradient; while the DCA ordination axis 2 revealed the variation tendency of plots with moisture condition. (2) In shrub communities, the DCA ordination axis 1 showed the change of moisture gradient, the DCA ordination axis 2 revealed the elevation changes. (3) In the herb communities, the DCA ordination axis 1 was in consistent with that of the shrub communities, while the DCA ordination axis 2 changed along the latitude from west to east. The variation tendency for DCA ordination of dominant species were in accordance with that of the plot DCA.Based on the result of TWINSPAN classification, the species diversity of the forest communities in Southern Shanxi was investigated by using species richness index (Ro), diversity index(λ and H’) and evenness index(Jswand E). The results indicated that the rank of species richness index for 12 associations are Association8> Association12> Associations> Association2> Association6> Association?> Association 10> Association3 > Association9> Association4> Association11> Associationl. The biodiversity index were the highest in the herb layer, followed by the shrub layer and the forest layer, which indicated that herb contributed most to the overall communities richness. One-way ANOVA for each index showed that R0 and H’had a significant difference (P<0.05), while the differences among A, Jsw and E are not significant (P>0.05).The species correlation analysis (Fisher’s exact test and Spearman rank correlation analysis), together with the cluster analysis, is used to classify the plant functional groups (PFGs) for forest communities and shrub communities. The PFGs for forest communities is divided into 5 groups, PFGs I:Quercus baronii, Forsythia suspense, Lonicera maackii and Spiraea pubescens; PFGs II:Quercus variabilis and Vitex negundo var. heterophylla; PFGs III:Robinia pseudoacacia, Platycladus orientalis and Lespedeza davurica; PFGs IV:Quercus wutaishanica, Cotoneaster multiflorus and Potentilla chinensis and PFGs V:Pinus tabulaeformis, Rosa xanthine, Carex lanceloata and Artemisia sacrorum.The PFGs of the shrub communities included 6 groups, PFGs Ⅰ: Ostryopsis davidiana; PFGs Ⅱ:Hippophae rhamnoides and Poa annua;PFGs Ⅲ:Wikstroemia chamaedaphne, Carex lanceloata and Potentilla chinensis; PFGs Ⅳ:Ziziphus jujuba and Bothriochloa ischaemum; PFGs Ⅴ:Vitex negundo var. heterophylla and PFGs VI:Rosa xanthina and Artemisia sacrorum.