ASHS 2025 Conference

Mulch films play a crucial role in enhancing crop yields and suppressing weeds; however, conventional plastic mulch films (PEMs) contribute significantly to environmental burdens, particularly at the end-of-life (EOL) stage. In response, soil-biodegradable mulch films (BDMs) have emerged as an alternative, offering potential benefits in reducing waste and emissions. This study conducts a cradle-to-grave life cycle assessment (LCA) of BDMs (PBAT/PLA, 30/70 PBAT/TPS, 70/30 PBAT/TPS blends) compared to PEMs (LDPE) across ten environmental impact categories in the production of 1 kg of strawberries per hectare in California, USA. Multiple EOL scenarios were evaluated, including soil-biodegradation, anaerobic digestion, and composting for BDMs, and landfill (with and without energy recovery) for PEMs. Results indicated that during the manufacturing stage, BDMs exhibited the lowest fossil fuel depletion, with the 30/70 PBAT/PLA achieving a 72% reduction; however, all BDMs had higher global warming potential (GWP). The highest environmental burdens in manufacturing were associated with BDM-PBAT/PLA due to its high energy requirements. During the mulch use stage, all BDMs consistently outperformed PEMs slightly in key impact categories such as GWP (reducing emissions by approximately 4.7%), acidification, and smog formation. No significant differences were observed among BDMs in this stage, suggesting that primary environmental distinctions arise from manufacturing and EOL scenarios rather than field application. The EOL stage significantly influenced the overall sustainability of mulch films. In terms of fossil fuel consumption, carbon emissions, and human toxicity potential, the most favorable scenarios were BDM-soil-biodegradation (-2.65 kg CO2-eq) and BDM-anaerobic digestion (-20.9 kg CO2-eq), both of which also reduced ecotoxicity (approximately -51 CTUe) and carcinogenic effects while minimizing fossil fuel depletion (approximately -1.72 MJ). In contrast, BDM-composting resulted in higher acidification (up to 0.344 kg SO2 eq) and smog formation, making it a less favorable option. PEMs, even under energy recovery scenarios, exhibited higher impacts and lacked the benefits of biodegradability, emphasizing the sustainability advantages of BDMs. When considering the full cradle-to-grave life cycle, BDMs demonstrated superior environmental performance under optimal EOL strategies. Although PEMs had a lower manufacturing footprint, their EOL challenges negated these benefits. Among BDMs, PBAT/TPS blends, particularly the 30/70 PBAT/TPS, exhibited the most balanced performance, offering reduced manufacturing burdens alongside excellent EOL outcomes. This study provides a detailed analysis of the environmental benefits and trade-offs of BDMs. The findings, along with nuanced recommendations, support the transition toward more sustainable mulch film applications.