Influence of Stocking Rates on Morphological Characteristics and Biomass of Deyeuxia angustifolia

Four grazing districts:lightly grazed(0.99AU/hm2·month,LG),moderately grazed(1.65AU/hm2·month,MG),heavily grazed(2.30AU/hm2·month,HG)and no grazed(0AU/hm2·month,CK)were set on Deyeuxia angustifolia meadow in northeast Sanjiang Plain,the morphological characteristics and biomass of Deyeuxia angustifolia under different grazing intensity were studied.The results showed that:(1)Grazing reduced the vertical height and node number and increased leaf laminas of Deyeuxia angustifolia;leaf number increased significantly while node number decreased significantly under moderate and heavy grazing,but light grazing showed less influence.(2)At the beginning of grazing the stem-leaf ratio under heavy grazing was significantly higher than other district(P0.05),and in July to August the stem-leaf ratio under moderate grazing was the greatest while that under no grazed was the least.(3)Grazing mainly affected soil surface(0~10cm)roots,and the roots number decreased in different level,the root number under heavy grazing reduced the most;lightly grazing(0.99AU/hm2·month)was good for maintaining high living root rate.