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机构地区:[1]甘肃省肃南县神鹿股份有限公司种羊场 肃南,734400 [2]兰州大学草地农业科技学院 甘肃省草原生态研究所,兰州730020 [3]甘肃省教育学院,兰州730000
出 处:《草业学报》2002年第3期66-71,共6页Acta Prataculturae Sinica
基 金:国家自然科学基金重点项目(39630250)资助
摘 要:高山草原夏季牧场的牧草营养物质富余达1倍以上,秋季牧场供需相当,冬季可满足80%左右,春季不到40%;草地上的载畜量和畜增重夏牧场是5.08羊单位/hm2和27.22kg/hm2,秋牧场是5.59羊单位/hm2和31.83kg/hm2,冬季牧场是1.64羊单位/hm2和-4.38kg/hm2,春季牧场是1.64羊单位/hm2和-7.10kg/hm2。在牧草增长率和绵羊种群采食率轨迹图中出现2个平衡点,表明夏、秋牧场的牧草生产有贮藏效应,冬、春牧场为牧草亏缺期。只有采用系统耦合的效应力,方可使放牧系统健康发展。<Abstrcat>The output of herbage in summer range exceeded sheep need and corresponded to demand in fall, but lacked 20% in winter and 60% in spring in alpine meadow of Sunan.The grazing capacity and the gain in wiehgt of sheep were different in seasons:5.08(sheep unit)/hm2 and 27.22 kg/hm2 in summer alpine meadow; 5.59(sheep unit)/hm2 and 31.83 kg/hm2 in fall alpine meadow, 1.64(sheep unit)/hm2 and -4.38 kg/hm2 in winter alpine meadow, 1.64(sheep unit)/hm2 and -7.10 kg/hm2 in spring alpine meadow, respectively. The results indicated that the output of herbage in summer and fall appeared a store effect and the use of system coupling principle between alpine meadow and farmland could take the system of grazing development healthy only.
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