天祝抓喜草原不同牦牛放牧强度对牧草生长的影响

Tianzhuzhuaxi Grasp Grassland Different Yak Grazing Intensity Effects on Forage Growth

高寒草原牧草生长缓慢,生态环境脆弱。试验就不同牦牛放牧强度对牧草生长的影响进行了研究。结果表明,低强度的放牧活动在随后的3年中牧草的产量基本保持一致,其差异性不显著(P>0.05),也就是说低强度放牧活动不但对草原牧草构不成危害,而且还有益处。禁牧及高强度放牧活动,在随后3年的牧草产量逐年下降,差异显著(P<0.05),即它们对草原牧草的危害较大。禁牧及不同放牧试验区在全部禁牧之后的3年平均产量的分布曲线呈现倒“V”字形,禁牧及放牧强度过大对草原有破坏作用呈现“双向退化现象”。

The alpine grasslands are characterized by slow growth and fragile ecological environment. The effects of different yak grazing intensity on herbage growth were studied. Experimental results showed that the yield of herbage under low-intensity grazing remained basically the same in the following three years, and the difference was not significant (P> 0.05). That is to say, low-intensity grazing not only did no harm to the pasture structure, but also had benefits. In the following three years, the yield of herbage decreased year by year with significant difference (P< 0.05), that is to say, they did great harm to grassland herbage. The average yield distribution curve of 3 years after the ban of grazing and different grazing areas presented an inverted “V” shape, and too much ban of grazing and grazing intensity had a destructive effect on the grassland, presenting a “two-way degradation phenomenon”.