Relative coverage of ALG gradually increased with increase of grazing intensity.Heights of the three functional types of Gramineae all decreased with increase in grazing intensity.

• 一年生优质牧草在各样区的相对盖度表现为中牧区＞低牧区＞重牧区＞封育对照区,说明放牧干扰有提高此相对盖度的影响;