College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, 100193, Beijing, PR China.
College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, Key Laboratory of Plant-Soil Interactions, Ministry of Education, China Agricultural University, 100193, Beijing, PR China.
J Environ Manage. 2022 Jan 15;302(Pt A):113960. doi: 10.1016/j.jenvman.2021.113960. Epub 2021 Oct 23.
The rapid specialization of livestock production in China has contributed to spatially decoupled crop and livestock production, leading to various environmental pollution issues. Some regional agro-environmental policies have recently promoted the coupling of specialized crop and livestock farms through cooperation. However, the environmental and economic performances of such cooperation remain unclear. This study investigated multiple environmental footprints of two contrasting production systems: cooperative crop-livestock systems (CCLS) and decoupled specialized livestock systems (DSLS), using survey data of 87 ruminant farms in Northwest China. Results show that farms in CCLS had lower net greenhouse gas (GHG) emissions (12-29%), lower reactive nitrogen (Nr) emissions (21-40%), lower phosphorus footprints (PF) (41-54%), and used less cropland (24-31%) per kg animal product, compared to those in DSLS. The large differences in GHG emissions between the two systems were mainly related to enteric fermentation and resource production (used for feed production). The differences in Nr emissions and PF were mainly related to manure management. Net profits per kg animal product were higher in CCLS (13-35%) than in DSLS, and most profits originated from lower purchasing costs of feed and young livestock. Net profits and environmental footprints were negatively correlated, suggesting an environmental and economic win-win situation for CCLS. The possible obstacles to recoupling specialized crop and livestock farms through cooperation have been discussed, including farm size, contract stability, and local policies. Our study provides science-based evidence to support policymakers and specialized farms to close nutrient loops between crop and livestock production sectors through regional cooperation.
中国畜牧业的快速专业化导致了作物和畜牧业生产的空间脱钩，从而引发了各种环境污染问题。最近，一些区域性农业环境政策通过合作促进了专业化作物和畜牧场的耦合。然而，这种合作的环境和经济绩效尚不清楚。本研究通过对中国西北地区 87 个反刍动物养殖场的调查数据，调查了两种对比生产系统（合作作物-畜牧业系统（CCLS）和脱钩专业化畜牧业系统（DSLS）的多个环境足迹。结果表明，与 DSLS 相比，CCLS 中的农场的净温室气体（GHG）排放（12-29%）、活性氮（Nr）排放（21-40%）、磷足迹（PF）（41-54%）和每公斤动物产品所需的耕地（24-31%）都较低。这两种系统之间 GHG 排放的巨大差异主要与瘤胃发酵和资源生产（用于饲料生产）有关。Nr 排放和 PF 的差异主要与粪便管理有关。CCLS 中每公斤动物产品的净利润（13-35%）高于 DSLS，而大部分利润来自饲料和幼畜购买成本的降低。净利润和环境足迹呈负相关，这表明 CCLS 实现了环境和经济的双赢。讨论了通过合作重新耦合专业化作物和畜牧业农场的可能障碍，包括农场规模、合同稳定性和地方政策。我们的研究为政策制定者和专业化农场提供了基于科学的证据，以支持通过区域合作在作物和畜牧业生产部门之间实现养分循环。
