大针茅草原植物群落和绵羊增重对载畜率的响应

Response of Plant Community and Sheep Live Weight to Stocking Rate in Stipa grandis Steppe

本文研究了不同载畜率大针茅草原植物群落特征的响应和绵羊的体重变化,目的是确定大针茅草原的适宜家畜载畜率。研究结果表明,在中等载畜率植物群落结构保存较好,获得了最大的绵羊增重;重度放牧虽然获得了较大的绵羊体重增量,但对植物群落结构的破坏也较大,表现为群落中一年生植物和杂类草增多,牧草高度降低,盖度减小,产量下降,说明大针茅草原对放牧干扰的耐受性是有一定限度的,过度放牧会破坏草地植物群落的结构。

Plant community and sheep liveweight under different stocking rates were discussed in Stipa grandis steppe in order to deter- mine the proper stocking rate. The results indicate that moderate stocking rate showed better plant community structure and maximum live- weight gain of sheep, although heavy stocking rate reached better liveweight gain, but destroyed plant community structure, which showed the increase of annuals and forbs, decline of plant height and coverage, biomass. As a conclusion heavy stocking rate was not good for plant community due to the limited tolerance of Stipa grandis steppe to grazing.