Species composition and diversity of plants at different successional stages in small catchments of karst areas

This study focused on the composition and species diversity of plants during different succession periods based on a field investigation in Houzhai Valley in Puding County, a karst area in Guizhou Province in Southwest China. The results showed that the vegetation in this area was mainly in four succession stages: grassland, shrub grassland, shrub forest and arbour forest. There were also some artificial fruit-bearing forests. In summary, 97 families, 230 genera and 382 species were investigated and recorded in the studied region. The predominant three families with the largest number of species were the Rosaceae, Compositae and Poaceae. The percentage of the life forms as arbour, shrub, herb and rattan accounted for 14.66%, 29.84%, 43.46% and 11.52% of the total species, respectively. The species richness index and Simpson's diversity index were as follows: arbour forest > shrub forest > shrub grassland > fruit-bearing forest > grassland. The species evenness and Shannon–Wiener index were as follows: arbour forest > shrub forest > shrub grassland > grass > fruit-bearing forest. In different stages of vegetation succession in the karst area, the measures taken for the restoration of vegetation and afforestation should be based on the specific species. (author)