荒漠草原不同放牧制度对植物群落多样性及稳定性的影响

Experiments were conducted on desert grassland in Yanchi Country of Ningxia Hui Autonomous Region, China, to determine the effects of rotational grazing, continuous grazing and enclosure. The work studied the effect of the different grazing systems on the alpha community, beta diversity, diversity analysis, aboveground biomass and the stability. Compared to the enclosure, the rotational and continuous grazing resulted in greater species richness and diversity, but the differences were not significantly different as measured by the dominance index and evenness index (P>0.05). The continuous enclosure zone of the beta diversity was significantly higher than that of the other grazing grassland communities (p<0.05). The correlation analysis of the diversity index showed that the desert steppe community diversity index had significant correlations except evenness index. But there were no significant differences in the species richness index and dominance index when describing the community diversity (P>0.05). There was no significant correlations between the biodiversity index and community stability. For the intersection fitting, the two blocks of rotational grazing coordinates were 34.55 and 65.55. For the five types of rotational grazing, the most stable vegetation community was given by the shortest Euclidean distance of 20, 80.