A Global LCIA Frameworkfor Quantifying Seabed Damagefrom Bottom Trawling, Dredging, and Benthic Structures

Abstract The benthic zone provides the foundation for marine ecosystem health, yet seabed damage from anthropogenic activities remains mostly unrepresented in life cycle impact assessment (LCIA). Here, we present a globally applicable LCIA characterization framework for seabed damage from three major disturbance categories: bottom trawling, dredging, and structures on the seabed. We calculate 3,800 characterization factors (CFs) across 231 marine ecoregions (MERs), including 1,900 regional CFs and 1,900 globally normalized CFs derived using global extinction probability (GEP). MER-level CFs are presented for four trawling gear types, dredging, benthic structures, as well as generic-fish and species-level trawling CFs. Species-level CFs for 51 commercially significant fish species are expressed in PDF*yr/kg, which is a functional unit directly usable by practitioners conducting life cycle assessments of seafood and marine industries. The customizable structure of the framework allows practitioners to match assessment precision to available data. Together, these advances strengthen the capacity of LCIA to account for seabed damage across the seafood, energy, and marine infrastructure sectors.