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The purpose of this study was to evaluate the anticipated environmental benefits from integrating a dairy farm and a greenhouse; the integration is based on anaerobic digestion of manures to produce biogas energy, biogenic CO 2 , and digested slurry. A full Life Cycle Assessment (LCA) has been conducted on six modeled cases applicable in British Columbia, to evaluate non-renewable energy consumption, climate change, acidification, eutrophication, respiratory effects and human toxicity. Compared to conventional practice, an integrated system has the potential to nearly halve eutrophication and respiratory effects caused by inorganic emissions and to reduce non-renewable energy consumption, climate change, and acidification by 65–90%, while respiratory effects caused by organic emissions become negative as co-products substitute for other materials. Co-digestion of other livestock manures, greenhouse plant waste, or food and food processing waste with dairy manure can further improve the performance of the integrated system. [ABSTRACT FROM AUTHOR]

Symbiotic integration of agricultural activities is widespread but quantitative assessments of the environmental benefits are scarce. To explore the potential benefits of applying the industrial symbiosis approach in agriculture and horticulture, a detailed case study is reported of a potential Eco-Industrial Park (EIP) including three activities: dairy farming, greenhouse cultivation of vegetables, and mushroom growing. These activities are widespread world-wide but, to enable quantitative assessment, the specific EIP studied is located in the Canadian province of British Columbia (BC). The activities are linked by anaerobic digestion of dairy manure to produce biogas and digestate. Biogas replaces natural gas to supply heat to the farms and carbon dioxide (CO 2) to the greenhouse. Digestate is separated into a liquid fertilizer and a solid substrate; the former replaces chemical fertilizers and the latter can be utilized as cow bedding and growing medium for plants and mushrooms. Mushroom growing emits CO 2 which is conventionally ventilated but can be used for stimulating plant growth in the greenhouse. Life Cycle Assessment (LCA) is used to quantify the environmental benefits of the EIP compared to conventional independent farms. Non-renewable energy consumption, greenhouse gas emissions, aquatic acidification, respiratory effects from organic emissions, and human toxicity can be reduced by 50%–90% and aquatic eutrophication and respiratory effects from inorganic emissions can be reduced by more than 10%. Such EIPs can also alleviate nutrient management problems in regions with intensive livestock farming. • An LCA model of EIP linking AD of dairy manure, greenhouse and mushroom operations. • Exchange of by-products enhances energy and material self-sufficiency. • Digestate utilisation within the EIP improves nutrient management. • Reductions of ∼60% achievable in non-renewable energy use and global warming potential. • Reductions of 10%–90% achievable across five other life cycle impact categories. [ABSTRACT FROM AUTHOR]