Analysis on Interspecific Relation of Dominant Species of Plant Communities During Succession on Abandoned Farmlands in Guancei Mountain,Shanxi

Succession data were collected from the filed in different succession stages simultaneously.On the basis of TWINSPAN,the interspecific relations of dominant species plant communities' during succession on abandoned farmlands in Guancei Mountain Shanxi were studied by using χ2-test and Spearman's rank correlation coefficient.The results indicated that:(1) 39 samples were divided into seven groups,belonging to the three stages of vegetation succession by using TWINSPAN classification being the herbaceous stage (including Assoc.I1,I2 and I3),the scrub community stage(including Assoc.II1 and II2) and the forest community stage (including Assoc.III1 and III2) respectively.(2) On the basis of χ2-test,the species-pairs relationship was analysed by using Spearman's rank correlation coefficient.The result showed that the species-pairs relationships were different in different succession stage.For example,the species-pair Artemisia sacrorum and Astragaolus was positive association in the herbaceous stage but was negative association in the scrub community stage.This was probably because of the difference that species adapted to different micro-environment and showed.But the proportion of the positive and negative associaton showed the trend of increasing (0.78→0.86→1.09),it indicated that the plant community was developing to a stable community.(3) The result of this study agree with the view that the plant community tends to the stable stage with the development of the plant community succession,that is,the longer the time of succession is,the higher the positive associaton ratio is,the steadyer the structure of the plant community is,the stronger the ability of species coexisting is.