Combining ecosystem indicators and life cycle assessment for environmental assessment of demersal trawling in Tunisia

Abstract

Purpose The present study assesses environmental performance of seafood production by demersal trawling in Tunisia (Gulf of Gabes) in order to analyze the contribution of each production stage to environmental impacts and to understand drivers of the impacts using life cycle assessment (LCA). Then a set of ecosystem quality indicators were determined using an ecosystem modeling tool, Ecopath with Ecosim (EwE), and were combined with LCA to increase the relevance of both tools' assessments when applied to fisheries. Methods The approach consisted of conducting LCA and calculating ecosystem indicators to provide a complete assessment of trawling's environmental impacts and the ecosystem characteristics associated with seafood production. The functional unit for the LCA was set to 1 t of landed seafood, and system boundaries included several operational stages related to demersal trawling. Several ecosystem indicators from EwE were calculated. Demersal trawling in the exploited ecosystem of the Gulf of Gabes (southern Tunisia) was used as a case study to illustrate the applicability of the approach. Several management plans were simulated and their influence on environmental performance was assessed. Ecospace, the spatial module of EwE, was used to simulate management scenarios: establishment of marine protected areas, extension of the biological rest period, and decrease in the number of demersal trawlers. Results and discussion LCA revealed that fuel consumption by fishing vessels, fuel production, and paint and antifouling production contributed most to environmental impacts. All management plans simulated decreased environmental impacts compared with the baseline scenario. The most effective management plan is extending the rest period, which increases demersal trawler yield and greatly decreases the PPR/catch of demersal trawlers. Conclusions The method developed in this study is relevant for supplementing LCA of fisheries and potentially that of seafood production systems. It provides policy makers with practical information to help implement effective management plans in the context of an ecosystem approach to fisheries.

Status of Life Cycle Assessment (LCA) in Africa

“…Primary data/Ecoinvent v3.3/Agrifootprint 3.0 ILCD Tunisia [198] Electricity 1 MWh of electricity generated Primary data/WIOD/SimaPro ILCD Tunisia [199] Electricity 1 kWh of electricity output Primary data/Existing literature ILCD Tunisia [200] Olives 1 ton of olives and 1 ha of cultivated olive growing area Primary data/Ecoinvent v3.2 ILCD Tunisia [201] Seafood 1 t of landed seafood Primary data/Ecoinvent v3 ILCD Uganda [202] Sanitary products…”

Life cycle assessment of glass/polyester laminates used in the shipbuilding industry and its fire behavior

“…The impact category that describes an adverse effect of toxic substances on the terrestrial ecosystems is a terrestrial ecotoxicity potential (Abdou et al, 2020). The most impacting is the UPR which implies a 0.43% of the overall impact (3.12E-14 kg 1,4-DCB).…”

Environmental performance of Cantabrian (Northern Spain) pelagic fisheries: Assessment of purse seine and minor art fleets under a life cycle approach

“…It is important to mention that more specific impact indicators were not used for the main drivers of marine biodiversity loss (e.g. seafloor area impact or specific discard indexes (Abdou et al, 2020), as although they are currently used by some LCA practitioners (Vázquez-Rowe et al, 2012b), their methodology is not yet fully developed and standardised, coupled with the fact that there are different levels of uncertainty in terms of hedging of cause-effect pathways and spatial coverage of damage (Woods et al, 2016). This gap in research also encompasses the lack of consideration of the consequences of leaked plastic waste on the environment (Woods et al, 2021).…”