Quantitative Analysis Of Ecological Relations Of Plant Communities In Guanqin Mountain, Shanxi

Guanqin Mountain is well covered with forests It is representative and diverse, has important roles not only in the water and soil conservation but also in the regional economics. This thesis selected the Guanqin Mountain located at the north cordillera of Luliang Range, as study area, to study the ecological relation, species diversity, niche of constructive and dominant species and interspecies correlation.This thesis, based on the survey of community plots, analyzed the relations of plant communities at Guanqin Mountain using TWINSPAN (Two Way Indicator Species Analysis) and DCA (Detrended Correspondence Analysis) methods, finally gave 8 community types. The result of DCA ordination shows that different plant communities and their distribution areas vary along the environmental gradient in the ordination graph. The first axis of DCA denotes altitude change and the second axis of DCA denotes change of water equivalent in the soil, and diagonal denotes the change of temperature, water-conditions and aspect and slope in communities. The ordination graph of dominant species in the plant community is very similar to that of plant community types. This suggests that the distribution of dominant species in plant communities determines the distribution pattern of plant community types to some extent.By using of the richness, diversity and evenness indices, species diversity and diversification mechanism were studied. Result shows that community diversity goes up with the elevation decrease. The two main reasons for that are, the species gradually become scarcity in forest of Picea wilsonii and Larix principis ruprechti-I, and the arboreal layer is simple in forests with the elevation increase. The result reflects the actual circumstance of communities and with the role of environment conditions.By using the niche breadth, niche overlap, and TWINSPAN, DCA, we study the roles of the dominant species in communities and the relationships of communities. The results are as follow: the decisive factors affecting...