The influence of grazing intensity on community characteristics and diversities of Deyeuxia angustifolia meadow in Sanjiang Plain was studied. No grazing, light grazing, moderate grazing and heav-y grazing were set in the experiment. The results showed that plant species in the community were increased by grazing, and most of them were Gramineae, Compositae, Rosaceae and Polygonaceae. The species diversity and stability of the community were the best under moderate grazing intensity. The important value of perennial plants was reduced by grazing and important value of annual plants was increased a little. The density of Deyeuxia angustifolia , Sonchus brachyotus were all decreased under different grazing intensity, and dandelion was increased.%设轻度(0.87头牛/hm2)、中度(1.42头牛/hm2)和重度(1.94头牛/hm2)三种放牧强度,以不放牧作为对照,采用样方法对三江平原小叶章草甸群落特征及物种多样性进行研究.结果表明:放牧1年,三种放牧强度均能增加群落的物种数,增加的物种多为禾本科、菊科、蔷薇科和蓼科植物.其中,在中度放牧强度下群落物种多样性和稳定性最优.放牧降低了多年生植物的重要值,一年生植物的重要值有小幅增加.放牧对草地主要植物种群密度的影响存在差异,三种放牧强度下小叶章、苣荬菜种群的密度降低,蒲公英种群的密度升高.
展开▼
