基于氮素循环的耕地畜禽承载能力评估模型建立与应用

为了避免畜禽粪便大量流失对环境构成威胁,指导农区畜禽养殖规模合理配置与布局,建立农牧结合、种养平衡、生态循环、环境友好型现代动物农业可持续发展产业模式,提供直观、实用、易行的科学方法,该研究基于农牧生产系统中"耕地-作物-畜禽"氮的流动循环规律及养分收支平衡原则,运用畜牧生产学及线性规划的理论与方法,引入猪饲料蛋白当量及粪便氮排泄当量等参数,设计建立农区耕地畜禽承载能力评估数学模型(N-LSCM)。并以四川农区为案例分析评估表明,2006年该农区畜禽养殖规模较为合理,对环境不构成威胁,且仍有新增22419574头猪(杜洛克×长白×大约克夏三元杂交,出栏体质量100kg的商品肉猪的头数)的发展潜力。

Modeling and application of livestock supporting capacity estimation of cropland based on nitrogen cycling in southwest China

Livestock waste poses a great pollution to the cropland and even results in eutrophication of environment if agricultural farming-animal husbandry ecosystem is not soundly planned.In this study,a mathematic model to estimate livestock supporting capacity of cropland was built based on nitrogen cycling in form of agricultural farming-animal husbandry ecosystem(N-LSCM).The parameters necessary to this model are pig feed protein equivalent,nitrogen excretion equivalent and nitrogen consumption per unit yield of crops.In order to test this model,the actual data of Sichuan province of southwest China were used as a representative situation,and the calculation results showed that in 2006,the agricultural scale of livestock and poultry was reasonable,it did not pose a threat to the environment,and there was still an increase potential in livestock of 22 419 574 pigs(Duroc×Landrace×Yorkshire,slaughtering weight 100 kg).The model can also be used for risk assessment of livestock-environment.