Quantitative Analysis On Ecological Relationships Of Dominant Populations Of Abandoned Land In Guandi Mountains, Shanxi

The plant communities of abandoned land in Guandi Mountain, Shanxi, were studied by quantitative ecology methodology, including the classification and ordination of those communities, the interspecific relationships of the dominant species, and species diversity, this research could be take as the basis for the vegetation restoration in abandoned land and vegetation succession .52 plots from the field were divided into 10 associations by TWINSPAN, and the ordination of those plots were analyzed by DCA . The result of DCA showed that the first axis of samples DCA ordination chart reflection jamming degree change, plant community dominant species DCA ordination chart first axis reflection moisture condition change gradient. The ordination graph of dominant species is very similar of the community types by TWINSPAN, and the distribution of dominant species determines the distribution pattern of plant communities to some extent.The interspecific relationships among 31 dominant populations of the communities were studied by using x~2- test for 2×2 contingency tables, Pearson's correlation coefficient test and Spearman's rank correlation coefficient test respectively. The results showed that: 1) 227 species-pairs were positive association, 231 species-pairs were negative association, and the number of species-pairs being significant (p<0.05) made accounted for 7.26 % in the total species-pairs by x~2 test. 14 species-pairs were higher significant (p<0.01), while 15 species-pairs were significant (p<0.05), which was testes by Pearson's correlation coefficient. 201 species-pairs were positive correlation, including 10 species-pairs were higher significant positive correlation and 24 species-pairs were significant positive correlation, and 263 species-pairs were negative correlation, including 8 species-pairs were higher significant negative correlation and 28 species-pairs were significant negative correlation, which were tested by Spearman's rank correlation coefficient. The species-pairs being significant (p<0.05) made accounted for 15.05%, the interspecific relationships was not significant (p>0.05) in the most dominants of this community by Spearman's rank correlation coefficient test. 2) According to the adaptability to the environment and the relationships between plants and environment, 31 species were divided into 2 ecological species groups: Phragmites group and Poa group.The species diversity was studied by using richness indices, speciesdiversity indices and evenness indices, and the difference among theseindices for all communities were studied by analysis of variance and Duncanmultiple rang test respectively. The results indicated : (1) The abandon landfor 5a belongs to the vegetation succession initial period. The sequence of thespecies diversity indices was follows: Ass. Medicago falcate> Ass.Phragmites aitstralis+ Geranium sibiricum+ Medicago falcate> Ass.Geranium sibiricum+Roegneria kamoji+Ixeridium sonchifolium> Ass. Asterataricus+ Artemisia scoparia> Ass. Eragrostis pilosa + Phragmitesaustralis+ Geranium sibiricum> Ass. Lxeridium sonchifolium+ Artemisiascoparia+ Phragmites australis> Ass. Anthriscus sylvestris+Phragmites australis> Ass. Leymus secalinus+ Artemisia scoparia +Phragmites australis>Ass. Geum aleppicum> Ass. Astragalus adsurgens+Phragmites australis+ Artemisia scoparia. (2) Because of the difference ofcommunity structure was too big, various communities group kinds of the companion specie have most difference.λ, H' were better than the others after the 5 species synthesis multiple indices carry on the comparison.