Potential pathways to reduce environmental impact in a greenhouse tomato production: Life cycle assessment for different irrigation and fertilization treatments

•LCA was a valuable methodology to compare environmental impact between treatments.•The system boundary was from greenhouse construction to tomato harvest in the study.•The tomato production stage dominated the WD and toxicity impact.•Manure application reduced the environmental impact for all categories except for toxicity. Greenhouse vegetable cultivation with high productivity but also with high resource consumption has rapidly developed in Northern China. A comprehensive assessment of environmental impacts from the greenhouse production is vital to identify the important contribution processes and propose potential solutions to alleviate the environmental burden. A life cycle assessment (LCA) was used to examine the environmental impacts of greenhouse tomato production with the system boundary from greenhouse construction to tomato harvest. The impact of two fertilizers (organic and inorganic) under two irrigation levels was also compared. Nine impact categories including resource demand of energy consumption (EC) and water depletion (WD), pollution impact of global warming potential (GWP), acidification potential (ACP), eutrophication potential (EUP), and photochemical oxidation (PHO), and toxicity impact of territory toxicity potential (TTP), freshwater toxicity potential (FTP), and human toxicity potential (HTP) were selected to calculate the total environmental index. The results showed that the greenhouse construction stage contributed to 85.1% of EC, 91.0% of GWP, 68.1% of ACP, 93.2% of EUP and 89.4% of PHO while the tomato production stage resulted in more than 97% of WD and toxicity impact. After normalizing and weighting, FTP was the most environmental risk with an environmental index of 0.106, followed by EUP and ACP. For different treatments, organic fertilizer (N1) with low irrigation level contributed to the largest ironmental index of 0.295 while inorganic fertilizer (N2) with regular irrigation level had the least. Organic fertilizer generally had lower environmental burden in all impact categories with an exception of the toxicity impact. Due to the stronger release of heavy metals, N1 had higher TTP, FTP and HTP than N2. Reducing heavy metals content in organic fertilizers, optimizing organic fertilizer application regime, extending the greenhouse life span, and recycling or reusing the construction materials are recommended to mitigate the environmental risks of solar greenhouse vegetable production.