放牧率对牦牛生产力的影响初析

通过2年的牦牛放牧试验,结果表明:放牧率对牦牛生产力有显著的影响,牦牛个体增重与放牧率呈线性回归关系;在试验期内,轻度放牧组的日增重较快,中度放牧次之,重度放牧最慢,而且随着放牧率的提高,牦牛平均个体总增重依次为136.7kg,128.6kg,93.5kg,轻度放牧比中度放牧和重度放牧分别高6.3%和46.2%。经方差分析表明,3个处理的牦牛平均个体增重有显著的差异(P<0.05),进一步作新复极差测验,30%和50%之间差异不显著,但他们和70%之间的差异均显著。

Effect of Stocking Rate on Productivity of Yak Grazing on Alpine Meadow

The effect of stocking rate on the productivity of yak grazing on the alpine meadow wasstudied from June 28, 1998to May 30, 2000. The resultsindicated that stocking rate significantly affected the productivity of yak, and there was a relationship of linear correlation between the gain of yak and stocking rate. Within the trial period, the liveweight gain was 136.7kg/head,128.6 kg/headand 93.5 kg/head under light grazing, moderate grazing and heavy grazing respectively. The resultsof ANOVA analysis indicated that the averagegains among three treatments were significantly different (F =5.03 > F0.05 = 3.68). However, the SRR analysis showed that there was not a significant difference between light and moderate grazing, and the differences between light grazing and two others were significant.