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机构地区:[1]中国科学院植物研究所内蒙古草原生态系统定位研究站,北京100093
出 处:《草地学报》1999年第3期182-182,共1页Acta Agrestia Sinica
基 金:国家科委"九五"攻关项目!96-016-01-01;中国科学院"九五"特别支持项目!KZ95T-04-03;重大项目!KZ951-A1-301;内蒙古草原生态系
摘 要:(1)绵羊个体增重与放牧率呈线性负相关,个体最大增重临界放牧率,因季节不同而变化,随着个体增重与放牧率回归系数b绝对值的增大而降低,以始、终放牧期间所得临界放牧率最小,(2.04羊/hm2)。(2)公顷增重与放牧率的关系符合二次曲线,在达到公顷最大增重以前,随着放牧率的增大而增大,之后则随着放牧率的增大而下降,平均5.43羊/hm2。(3)公顷最大增重并不一定获取公顷最大利润,主要视买卖价格及其差值而定。(4)以冷蒿小禾草为主的退化草原,宜以个体最大增重的适宜放牧率作为管理标准,以使该类草原在利用中得以恢复。The experiment results are showed that: ①there was linear negatively correlation between weight gain per sheep with stocking rate, the regression equation was Ga = 22. 5-1. 85S,r2 = 0. 92'; it was not constant about critical stocking rate as the liveweight gain per sheep was maximum,the value would decrease with grazing periods backward during the warm season; thc minimum valuc of critical stocking rate of maximum liveweight gain per sheep was about 2. 04 sheep/ha during warm season.②the regression equation was Gh =-8. 83 + 28. 90S-2. 66S2, r2 = 0. 94 . The critical stocking rate was also not constant while the total liveweight gain per hectare was maximum,its value was maximumin during July-Aug. and decrease with grazing years increase at the same paddock;the minimum critical stocking rate of maximum live weight gain per hectare was 5. 43 sheep/ha during warm grazing periods. ③the maximum benefit per hectare(RMB/ha)mainly depend on the price of buying and selling and their difference exception grassland status and animal performance,when buying price=selling price,the maximum benefit per hectare and its stocking rate were almost unchange. The stocking rate of the maximum liveweight per animal may be the optimal stocking rate for Artemisia frigida and short-grass degradational rangeland.
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