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作 者:徐敏云[1,2]
机构地区:[1]北京大学城市与环境学院,北京100871 [2]河北农业大学动物科技学院,河北保定071000
出 处:《草业学报》2014年第5期321-329,共9页Acta Prataculturae Sinica
基 金:中国科学院重要方向性项目(KSCX2-YW-G-076);中国科学院战略性先导科技专项(XDA05050304);保定市科技攻关项目(13zf063)资助
摘 要:草畜平衡问题是中国草地畜牧业的核心问题,草畜平衡的理论依据、计算参数存在着争议和分歧。本文主要依据中国载畜量和草畜平衡研究成果,总结了中国草畜平衡研究和实践上的困境。指出以平衡理论为基础的草畜平衡,对主要由降水驱动的干旱、半干旱草地并不具有指导意义。草地生产力时空变异大,根据平均生产力和家畜平均采食量核算的草畜平衡无法做到动态平衡;"季节畜牧业"、"关键场"等理论在解决草畜时空相悖上也充满挑战。家畜单位、存栏数量、合适放牧率等主要估算参数的争议,还不能为草畜平衡实践提供切实可行的决策依据。探索草畜适应性动态管理,协调草地生产的生态、社会和经济功能,应是中国草畜平衡未来的研究重点。Ascertaining the correct balance between forage supply and livestock demand is a critical issue for grassland animal husbandry in China.Calculations are typically based on theoretical models that balance energy availability and requirement,and adoption has been hindered by disagreement as to the size and response to va-rious factors of the theoretical coefficients used.In this article we summarize progress in China in livestock feed budgeting research.Adoption of forage-livestock supply and demand calculations based on average net primary productivity and animal feed intake for arid and semi-arid rangeland characterised by uneven precipitation and wide seasonal temperature fluctuation may not deal with the complexity and uncertainty arising from seasonal imbalance between supply and demand within the ecosystem.Despite considerable progress in solving tempo-ral-spatial disequilibrium between grassland productivity and livestock requirement,major challenges remain for “seasonal animal husbandry”and “key pasture”.Parameter estimates commonly used as a basis for forage-livestock balance decision-making require standardisation.In particular,there is no consensus as to the applica-tion or method of determining parameters such as livestock substitution rate,livestock numbers,and appropri-ate stocking rate,among others.In future,research into forage production-livestock demand balance should fo-cus on exploring opportunities to reduce seasonal imbalance between forage supply and livestock demand,and on coordination of the ecological,social and economic functions of grassland.
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