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Dr. Martín-Gamboa would like to thank the Regional Government of Madrid for financial support (2019-T2/AMB-15713). Ana Cláudia Dias would like to thank FCT/MCTES for the contract CEECIND/02174/2017 and for the financial support to CESAM (UIDB/50017/2020+UIDP/50017/2020) through national funds. A key goal in sustainable supply chain management is the minimisation of risk across supply chains. However, this is jeopardised by underdeveloped aspects such as social risk management, especially in the case of energy systems as they involve complex supply chains. This article constitutes the first time that Social Life Cycle Assessment (S-LCA) is used to lay the foundation for a methodological framework to define, assess and prioritise strategies oriented towards the minimisation of social life-cycle impacts across the supply chain of energy products. This framework combines S-LCA, a novel approach to the definition of alternative supply chain strategies, and multi-criteria decision analysis (MCDA). It was demonstrated through a case study of bioelectricity in Portugal by defining and assessing fifteen strategies on the specific supply chains of oil and fertilisers to check their suitability to enhance the system's social life-cycle performance. The weighted sum method (WSM) and Data Envelopment Analysis (DEA) were used as MCDA tools to further support decision-making by prioritising strategies. According to the results for a set of six social indicators, the strategies proposed on the supply of oil and nitrogen-based fertilisers were deemed suitable trade-off solutions to mitigate the social life-cycle impact of the bioelectricity system.

The European seafood and aquaculture sectors are facing important challenges in terms of environmental threats (climate change, marine debris, resources depletion), social development (worker rights, consumer's awareness) or economic growth (market and nonmarket goods and services, global competitiveness). These issues are forcing all stakeholders, from policy-makers to citizens and industries, to move to more sustainable policies, practices and processes. Consequently, an improvement in collaborations among different parties and beyond borders is required to create more efficient networks along the supply chain of seafood and aquaculture sectors. To achieve this, a â nexus thinkingâ approach (i.e. the analysis of actions in connected systems) combined with a life cycle thinking appears as an excellent opportunity to facilitate the transition to a circular economy.

Purpose Forest residues are becoming an increasingly important bioenergy feedstock. This study evaluates the environmental impacts associated with the production of fuel chips from eucalypt logging residues in Portugal, in order to identify the supply chains and machinery that bring the best environmental performance. Besides, the stages and operations with the largest environmental impact are identified.

Currently, most of the greenhouse gas (GHG) emissions are attributed to cities, as they are the global centers of business, residential and cultural activity, cities are expected to play a leading role in proposing climate change mitigation actions. To do so, it is important to have tools that allow the carbon footprint of cities to be assessed as accurately as possible. This study aims to quantify the carbon footprint (CF) associated with the activities developed in a Spanish city (Cadiz, Southwest Spain) by means of two available environmental methodologies, namely Environmentally Extended Input-Output Analysis (EEIOA) and Life Cycle assessment (LCA). When EEIOA is considered, two downscaling factors were proposed for the analysis due to the nature of the data handled (monetary data), based on the incomes (DF1) and expenditures (DF2) per inhabitant at city level. Regarding LCA, the rates of consumption of goods and production of waste per inhabitant have been processed to estimate the CF. The CF scores identified were 5.25 and 3.83 tCO2-eq·inhabitant-1·year-1 for DF1 and DF2 respectively, according to EEIOA, and 5.43 tCO2-eq·inhabitant-1·year-1, considering LCA. Therefore, a similarity can be concluded between the results obtained with both methodologies despite the inherent differences. Considering the results, the downscaling procedure based on income per inhabitant should be preferred, pointing to EEIOA as a good alternative to LCA for evaluating the CF at city level, requiring less time and effort. In contrast, EEIOA reports more limitations when critical flows were identified, which LCA can solve. Finally, this study can be of great interest to policy makers and city governments to know the CF and the main flows that contribute and in this way, can develop new policies and city models for reducing GHG emission new policies and city models for reducing GHG emission and addressing climate change.

Abstract This study evaluates direct and indirect environmental impacts associated with the consumption of goods and services by the households living in the municipality of Aveiro (Portugal) using environmentally extended input output (IO) analysis. The environmental impacts addressed are greenhouse gas (GHG) emissions and fossil fuel consumption. A methodology adapted to the specificities of the data available is proposed. This methodology relies on the Portuguese economic IO table, on GHG emission and fossil fuel consumption intensities, and on national household expenditure data downscaled to the urban level. This methodology could also be applied to other municipalities or cities for which data on local household expenditures are missing. This study also identifies the sectors with the largest impacts in order to prioritise strategies for reducing the impacts to move the municipality towards more sustainable consumption. The estimated total GHG emissions in 2005 amounted to 26 kg CO 2 -eq./cap/day and the total fossil fuel consumption was 7.3 koe/cap/day. The sectors that contributed most for both indicators are “land transport and transport by pipelines”, “food, beverages and tobacco”, “construction” and “production, collection and distribution of electricity”. Therefore, improvement measures are proposed for these sectors in order to more effectively decrease the environmental impacts related with GHG emissions and fossil energy consumption of the municipality.

Abstract This paper compares the water footprint profiles of four feedstocks used for biodiesel production: palm, soya, rapeseed and waste cooking oil (WCO). The profiles include: (a) a water scarcity footprint related to freshwater consumption impacts and (b) a water quality degradation footprint related to freshwater degradation impacts. The water scarcity footprint was assessed using two impact assessment methods: one based on water stress indices (WSIs) and the other on the available water remaining (AWARE) indicator. The water degradation footprint was assessed considering the environmental mechanisms covered by the impact categories of eutrophication, aquatic acidification, human toxicity and freshwater ecotoxicity. The water scarcity profiles ranged from 0.002 to 2.11 world m3eq kg−1 oil (WSI method) and from 0.008 to 133.57 world m3eq kg−1 oil (AWARE method). Both methods showed that the cultivation stage assumes the primary role in the water scarcity footprint results and identified the same systems with higher water scarcity footprints. However, for the oil systems with closer results, the rank order given by each method is different due to the characterization factors of each method. Nevertheless, the results obtained with the AWARE method give more comprehensive water scarcity footprint results than those obtained when applying WSIs because AWARE considers the aquatic ecosystem water demand. The water degradation footprint of virgin oils is mainly caused by fertilizers and pesticides used in cultivation. WCO systems present lower impacts for all impact categories with the exception of human toxicity-cancer. The choice of locations with lower water scarcity to produce oil crops can be a determinant in the calculation of lower impacts. Moreover, optimizing fertilization schemes or choosing climatic conditions that require less fertilizers, pesticides and water consumption can reduce the impacts of the water footprint profile of vegetable oils.

Social life cycle assessment of a bioelectricity system encompassing more than 400 processes within seven tiers of the supply chain.

SummaryTo support effective urban policies aimed at decreasing the environmental impacts of cities, it is important to develop robust tools for accounting those impacts. Environmentally extended input‐output analysis (EEIOA) is among the most used tools for this purpose, allowing the quantification of both direct and indirect impacts. Life cycle assessment (LCA) is also a holistic and comprehensive tool that accounts for direct and indirect impacts—but its application to cities is still very recent. This study aims at applying EEIOA and LCA to the municipality of Aveiro (Portugal) in order to compare the outcomes of the two tools in terms of total impacts (climate change and fossil fuel depletion) and hotspots (sectors/products contributing most to the impacts), to identify limitations and advantages of the tools when applied to Aveiro, and to illustrate how LCA can be applied to cities. The total impacts estimated with LCA and EEIOA were similar and the hotspots were also the same: transports, food, construction, and electricity. However, the relative contribution of some sectors was very different in the two tools due to methodological differences mainly in system boundaries, type of activities or products considered in each sector, and geographical coverage of impact data. This study concludes that the analyzed tools can provide complementary results to support decision making concerning urban planning and management.