LCA of tomato greenhouse production using spatially differentiated life cycle impact assessment indicators: An Albanian case study

Albanian grown tomatoes have been more export-oriented, with a rising interest forcommunicating environmental information using a life cycle assessment (LCA) approach. Meanwhile, spatial differentiation and inclusion of new impact categories are at the forefront of agriculture-related LCA research. In this context, ReCiPe 2016, most recent impact model covering 21 output indicators (6 spatially differentiated) was used to generate a full-fledged LCA of greenhouse tomatoes in a typical Albanian farm. Assessment per 1 ha of cropped land produced 18 midpoint indicators and 3 endpoint indicators and distinguished foreground (on-farm) and background (off-farm) systems. Most important midpoint categories for study area identified from foreground-background analysis were global warming (3109.85 kg CO2-eq), stratospheric ozone depletion (0.0298 kg CFC11-eq), particulate matter formation (10.47 kg PM2.5-eq), human health and ecosystem ozone formation (17.67 and 38.5 kg NOx-eq), water consumption (5060.6 m3), and terrestrial acidification (53 kg SO2-eq). The foreground is the most impacting system for damages to human health (caused by particulate matter formation, water consumption, and global warming) and ecosystem quality (caused by terrestrial acidification and ecosystem damage ozone formation). The background system (production of raw materials) has a major impact on 10 midpoint impact categories. The impacts primarily originated from nitrogen-based fertilizer emissions and diesel fuel with the origin of the impact from nitrous oxide (N2O), ammonia volatilization (NH3), nitrous oxides (N2O), nitrogen oxides (NOx) and non-methane volatile organic compounds (NMVOCs). Water consumption was dominated by irrigation water use. A sensitivity analysis indicated that nutrient emission factor model, spatial differentiation, or energy source generate different results and outlooks about the relevance of different processes, impact categories, and overall LCA performance. Site-dependent characterization of environmental impact resulted in variation from 6.1% to 77.1% compared to site-generic characterization, highlighting the importance of a multi-impact and spatial approach to increase the discriminating power of LCA.