Environmental costs and mitigation potential in plastic-greenhouse pepper production system in China: A life cycle assessment

Intensive vegetable system is commonly considered as high environmental costs due to high inputs, thus quantifying the mitigation potential of various environmental impacts, and developing strategies to improve the sustainability of this system was critical. Here we used partial life cycle assessment (LCA) to quantify the environmental impacts of a plastic-greenhouse pepper production system in China, and then employed an environmental impact gap methodology to analyze the mitigation potential of various environmental impacts and to establish better management strategy. The results showed that the global warming, acidification, eutrophication potentials and energy depletion of 160 farm-gate analysis were in average of 6.4 metric tons CO2-eq ha(-1), 54.5 kg SO2-eq ha(-1), 50.9 kg PO4-eq ha -1 , and 57.3 GJ ha(-1), respectively. Fertilizer accounted for 64.4%, 78.6% and 97.9% for the global warming, acidification, and eutrophication potential, respectively, while structural materials for greenhouse accounted for 58.6% of the total energy depletion. Based on analysis of yield gap and environmental impact gap by survey date grouping, the results showed that the pepper yield of the 1st quartile (best 25%) was 26.6% higher compared to the mean of all 160 farmer yields due to better nutrient and crop management. And at meantime, on per metric ton of pepper production, the global warming, acidification, eutrophication potentials and energy depletion were lower by 23.9%, 25.0%, 25.7%, and 23.2% in this system, respectively. In conclusion, the integrated nutrient-crop management strategies based on best famers' practices could close the gap of environmental impacts significantly.