| Base on the grassland restoration experiment in Yili pith plain,this article studied the relationship between the plant community diversity and the irrigation volume.The results showed: the water volume was the important factor in determining the vegetation growth in desert grassland;the vegetation coverage and Seriphidium transillense coverage were obviously improved when the irrigation volume was increased,and the grass yield and average plant height were distincty increased too.Furthermore,all of the Simpson index,Shannon-Wiener index,Pielou index and Margalf index tended to be increased when the irrigational volume was added.By calculation,it was found that the Simpson index increased 0.021 when the irrigation volume added 1 kg/d.Therefore,the plant diversity index is sensitive to water volume in temperate desert grassland. |