Methodological guidelines for the calculation of a WaterEnergy-Food nexus index for seafood products

Abstract

Indicators from Life Cycle Assessment (LCA) methodologies (i.e., footprints) have emerged as useful tools for identifying and communicating the environmental impacts of a system because of their accessible and intuitive understanding to non-expert public. However, the focus on a single environmental problem is one of their main drawbacks. Moreover, LCA studies have shown a lack of homogeneity in addressing the impacts related to seafood production systems, apart from these are often assessed on an individual basis. In view of finding a solution to this matter, the concept of Water-Energy-Food (WEF) nexus arises for raising awareness of the connections between the universal rights to water supply, energy security and food provision. Hence, this paper aims, on the one hand, to provide technical guidance to shed light on the harmonisation of LCA studies applied to the seafood sector and, on the other hand, propose a methodology for estimating a WEF nexus index (WEFni). For that, an integrative perspective was followed in which four indicators were selected to be integrated into one single value: carbon, water, energy and nutritional footprints. Likewise, the WEFni was shown in the form of an easy-to-read ecolabel for benchmarking seafood products, thus creating a useful communication channel between stakeholders: producers and consumers. Finally, the methodology introduced is expected to serve as reference to be applied to a series of cases studies of the European Atlantic area within the NEPTUNUS project. Despite this, certain aspects should be reassessed so that the WEF nexus ecolabel can be present in the seafood supply chain as well as in other food sectors, such as the indicators chosen or the normalisation, weighting and integration procedures considered.