The Study On Species Diversity And Interspecific Relationship Of Carpinus Turczaninowii Communities In The South Of Taihang Mountains, Shanxi

Great valley, located in the south of Taihang Mountains, has rich resources and great development potential in tourism. In recent years it has been exploited to be a famous scenic spot. To avoid vegetation degradation resulting from human activities and strengthen plant protection, Carpinus turczaninowii communities in great valley were selected as our research subject. The species diversity, interspecific association and correlation, niche breadth and niche overlap in these communities were studied using quantitative methods. In addition, the community types, structure and ecological relationships were also analyzed in this thesis.x~2-test and Spearman's rank correlation coefficient were used toanalyze interspecific relationships of 8 dominant tree species, 13 dominant shrubs and 20 dominant herbs respectively. The results showed that negative correlation between the edificator and Quercus liaotungensis was significant due to the different adaptability to the light condition. Species-pairs with similar ecological features which make them adaptive for similar habitats usually had positive association and correlation while species-pairs with different requirements were negatively associated and correlated. In general, the numbers of species-pairs with negative association and correlation were much more than that with positive association and correlation mainly because the forest was at a stable development stage. Compared with x~2-test, Spearman's rank correlation showed the more accurate and reliable results in this study.By using Levins and Shannon-Wiener's indices, the niche breadth of dominant species in three layers were measured. The results indicated that the species with broader niche had greater adaptability to the environment. Moreover, 37 quadrats were classified into 9 community types by TWINSPAN method, then niche overlap between dominant species in these 9 communities were calculated with Petraitis's index. The results showed theirdifferences in resource utilization and species composition clearly. Generally, species with similar ecological features or niche breadth tended to have greater niche overlap. But great niche overlap didn't necessarily lead to competition if their life forms were different, on the contrary, the relationships between them were very likely to be mutual beneficial.By use of Shannon-Wiener,Simpson and Hill diversity indices and Patrick, Margalef, Pielou indices, the species richness, species diversity and species evenness were measured. The results indicated that Shannon-Wiener and Hill diversity indices were strongly affected by richness. The species diversity had significant difference in the 9 communities. For instance, theicommunity with moderate water and light conditions had highest. species diversity. There were interactions among species diversity of the three functional layers, especially, the more species there were in shrub-layer, the less in herb-layer. In addition, the analysis of relationships between species diversity and environmental factors showed that aspect was closely related to species diversity , while the effects of elevation and slope on species diversity were not significant.