Spatial Distribution and Community Structure of Aboveground Biomass in Nature Grassland and Artificial Pasture
Through comparing the artificial reseeded alfalfa pasture and the degraded natural grassland in Binxian County,Shaanxi province,two kinds of the spatial pattern of aboveground biomass and their community structure were ascertained by analytical method of mathematical statistics model to establish a scientific theory basis for the vegetation restoration of degraded grasslands and for management of artificial grasslands in arid/semi-arid regions.The results showed that the spatial distribution of aboveground biomass of the main plants in the two grasslands well matched that in the gamma distribution model.The mean biomass (DM g · (0.25 m2)-1) in the improved grassland significantly surpassed that in natural grassland (P＜0.001),while the average species richness and diversity index per quadrat were significantly lower than the latter (P＜0.001).There revealed a negative correlation between the spatial heterogeneity index of the composition of plant species and the average biomass per quadrat in both grasslands.With the increase of species richness,the average biomass per quadrat increased in the natural grassland,but it decreased in the improved grassland.
grasslandgamma distribution modelcommunity structurebiomassspatial distribution
国家科技期刊平台
NSTL
万方数据
维普
