Influence of Short-period Grazing Intensity on Vegetation Characteristics and Diversity of Meadow Steppe in Zhaosu

The influence of short-period grazing intensity on vegetation characteristics and diversity in Zhaosu Meadow Steppe was studied by plot grazing experiment.The result showed that compared with CK,the height coverage and biomass of vegetation community under grazing condition were significantly decreased(P 0.05),the density was no significantly changed(P 0.05).There were no significant differences of vegetation characteristics among light grazing,moderate grazing and heavy grazing(P 0.05).With increasing the grazing intensity,the importance value of Carex liparocarpos was significantly increased,Stipa capillata was significantly decreased(P0.05),and the other species were relatively stable.The grazing conditions had significant influence on Shannon-wiener index and Pielous evenness index and light grazing reached the highest(P 0.05),but there were no significant influences on Margalef species richness,Simpson index,Mclntosh index and Alatalo evenness index(P 0.05).The short peoriod of grazing intensity had slower influence on the characteristics of pasture vegetation but fast influence on vegetation diversity.