Biodiversity of bryophytes and their characteristics of ecological distribution in the second Lindai karst bauxite area

This paper studied the bryophytes' biodiversity as well as their metallic elements of the growth substrate. The bryophytes were found in four different ecological environments in the second Lindai bauxite region in Zhanjie town of Qingzhen city,Guizhou province. As discovered in the study area, 37 bryophytic species belong to 22 genera and 10 families, of which Pottiaceae, Brachytheciaceae, Hypnaceae are the dominant families, Bryum, Campyloopus, Trichostomum, Brachythecium are the dominant genera and Ditrichum pallidum,Campylopus schwarzii, Molendoa japonica are the dominant species. The short turfs are the majority;and single-species community is the dominant community in this bauxite area.In this paper, Shannon-wiener and richness indexes were analyzed respectively.The results show that the diversity is highest in rapeseed planting area, followed by forest area in bauxite region.The diversity index is comparatively low in waste rock pile and bauxite soil dump rehabilitation areas, which have been heavily influenced by human activities. Pielous index in forest area is 0.8525, in waste rock pile area is 0.8327,in rapeseed planting area is 0.7650 and0.6229 in bauxite waste dump rehabilitation area. However, the β diversity index indicates that the highest biodiversity index (0.500) occurs in the bauxite soil dump rehabilitation and waste rock pile areas, while the lowest value(0.1538) occurs in the bauxite soil dump rehabilitation area and forest area in bauxite region. Furthermore, PCA results show that the bryophyte composition in bauxite soil dump rehabilitation area is different from that of waste rock pile area, characterised by the representative species Dicranella grevilleana and Barbula ditrichoides occur in the different areas, respectively. The bryophyte species with close species correlation are found to have attendant growth in karst bauxite mines.