不同放牧强度对牦牛生长和草地第二生产力的影响  

EFFECT OF DIFFERENT GRAZING INTENSITIES ON GROWTH OF YAK AND THE SECONDARY PRODUCTIVITY OF SWARD

作　　者：陈友慷 陈宇[1] 王晋峰[1] 陈智华[1] 文勇立[1] 周嘉友[1] 朱启明[1] 罗鹏[1] 

机构地区：[1]西南民族学院

出　　处：《草业科学》1994年第1期1-4,共4页Pratacultural Science

基　　金：UNDP和PAO援助项目

摘　　要：试验研究了６种放牧强度对牦牛生长及草地第二性生产力的影响。结果表明，放牧强度对牦牛日增重有明显影响（ｐ＜０．０１），日增重以０．２４牦牛单位／ｈｍ￣２处理组最高，达７０７．９ｇ，随着放牧强度的增大，牦牛日增重明显降低（ｒ＝－０．９２）。其中，放牧强度对１岁牦牛影响最大（Ｐ＜０．０１），２岁牦牛次之（Ｐ＜０．０５），３岁牦牛再次（Ｐ＜０．０５）。试验全期（６月９日～９月２７日）当放牧强度低于１．２牦牛单位／ｈｍ￣２时，增大放牧强度，草地第二性生产力明显提高（ｐ＜０．０１），当放牧强度高于１．２牦牛单位／ｈｍ￣２时，增大放牧强度，草地第二性生产力则呈下降趋势，但试验后期（７月１３日～９月２７日）草地生产能力则以０．７２牦牛单位／ｈｍ￣２组为最高。The effect of 6 grazing intensities on growth of yak and the secondary productivity of sward was studi-ed.The result showed that grazing in tensity significantly affect the daily weight increase of yak(P<0.01),which is the largest of0.2 4 yak unit per hm2,to 707.9g,and with the intensity increase,theweight obviously decrease (r=-0.92).The effect order on yak is 1 year old the biggest(P< 0.01),2years old the secondary(P<0. 05),3 years old the latest(P<0.05).During the whole test period ,whengrazing intensity is lower than 1.2 yak unit per hm2,grazing intensity increases,the secondary productivi-ty of sward increases significantly(P<0.01 ).But conversely,the secondary productivity of grassland willdecrease。In late period,the productivity of grassland is the highest of 0.72 yak unit per hm2.

关 键 词：放牧强度 日增重 草地生产能力 牦牛 

分 类 号：S823.43[农业科学—畜牧学]