Life cycle assessment of different strawberry production methods in Germany with a particular focus on plastic emissions

Abstract

PurposeUsing plastic for strawberry cultivation (so-called plasticulture) is widespread to extend cultivation, reduce weed stress and water and nutrient demand, and protect plants. We assess the environmental impacts of different plasticulture methods, including possible impacts caused by the (accidental) emission of plastics. The goals are to help farmers determine the most environmentally friendly cultivation technique and to test the inclusion of plastic pollution in life cycle assessment (LCA).MethodsAn LCA is conducted for a baseline scenario without plasticulture and 11 plasticulture scenarios. The scenarios are modeled using the regionalized ecoinvent 3.8 cut-off database. The functional unit is 1 kg of strawberries of marketable quality at the farm gate produced in the year 2021. The amounts of fertilizer, irrigation, and strawberry output of the scenarios are adapted depending on the plasticulture method based on an extensive literature review. The environmental impacts are assessed using the life cycle impact assessment methods of the Product Environmental Footprint (PEF) recommended by the Joint Research Centre of the European Commission, which is extended to account for plastic-related impacts. The impacts are normalized, weighted, and aggregated, resulting in one single impact score per scenario.Results and discussionThe scenarios using either a combination of conventional mulch film and row cover or biodegradable mulch film have the lowest total impacts; a macro tunnel or greenhouse causes the highest impacts. There seems to be no trade-off between maximizing productivity and lowering environmental impacts: the scenario with the highest yield also has one of the lowest overall impacts. Only direct emissions are considered regarding plastic pollution. Besides, the plastic pollution impact category is currently limited to the persistence of plastic in the environment and is extendable to but is not yet accounting for exposure and effect of plastic emission on humans and ecosystems.ConclusionPlasticulture can increase the yield and reduce environmental impacts for strawberry cultivation compared to open field cultivation. With the used normalization and weighting factors, plastic pollution makes up a considerable share of the overall environmental impact of strawberry cultivation, supporting the recent efforts of different research groups to include plastic emissions in LCA by developing suitable characterization factors.