Effect of grazing on vegetation characters in alpine meadow and its prediction model construction

Based on alpine meadow in Haiyan, Qinghai Province, we analyzed the effect of fencing and climatic conditions on vegetation characters from 2003 to 2015. The results indicate that: 1) The free grazing grassland aboveground biomass, canopy height were significantly lower than that of fencing land (from May to September) in recent 13 years, and the coverage on June and July significantly lower than that in fencing land. 2) Based on the data which were observed at the end of July in fencing grassland ,we found that canopy height a trend of parabola, and the coverage showed a power function trend; 3) The maximum value of annual aboveground biomass is consistent with the trend of average temperature from June to July, and has a significant power function relationship (P < 0.01), the impact of the precipitation for the remain delay, aboveground biomass and the year precipitation has a significant power function relationship; 4) We used SPSS l Linear regression analysis to build a prediction model for the aboveground biomass, which showed as follow: y = 124.44T_June-July + 2.59R_{previous year} – 2 180.23 (P < 0.01).