STUDIES ON THE COMMUNITY FEATURE AND RESOURCE DISTRIBUTION OF NOSTOC COMMUNE IN THE SOUTHERN SHANXI PROVINCE

The distrbution regularity of Nostoc commune in different living environments was studied by using the plot method.The community feature and biomass of the Nostoc commune community were analyzed.The results showed:(1) the specific composition of Nostoc commune community is 38 species,34 genera,21 families and 14 mon-family mon-species;(2) the vertical structure of the community is the shrub-layer and grass layer and cover plant layer;(3) average biomass of it is 10 kg/hm²,and dry weight 7 3 kg/hm² and wet weight 140 kg/hm²;(4) natural water content of it is 42% and water holding capacity 18.6%.The biomass is the largest in altitude 600～800 m;and (5) Nostoc commune consists with Bochriobloa ischaemum and Stipa in the distribution.