Optimizing the environmental sustainability of alternative post-harvest scenarios for fresh vegetables: A case study in Spain.

The aim of this research is to define different scenarios that optimize the environmental sustainability of the post-harvest stage of vegetable products (cauliflower and brassicas mix). These scenarios considered different packaging materials; energy generation technologies for the processing plant (standard electricity mix vs. renewable options); organic waste management (composting, anaerobic digestion, and animal feeding); and refrigerated transportation (local, national, and international, using diesel, natural gas, and hybrid trucks and railway). The analysis has been carried out based on a foreground inventory provided by a company that operating internationally, in accordance with the International Organization for Standardization (ISO) 14,040 methodological framework and following the latest Product Environmental Footprint (PEF) protocols. The analysis describes four midpoint categories, single score (SS) using EF3.0 life cycle impact assessment (LCIA) methodology and the Cumulative Energy Demand. The carbon footprint (CF) of the post-harvest stage for a base case scenario ranged between 0.24 and 0.29 kg CO2 eq/kg of vegetable, with a strong contribution associated to the production of packaging materials (57.8-65.2 %) and the transport stage (national range in conventional diesel vehicles) (31.5-38.0 %). Comparatively, lower emissions were associated with the energy consumed at the processing factory (up to 4.1 %) while the composting of organic waste management produced some impact savings (up to -3.5 %). Although certain differences were observed, the dominance of the transport stage and the packaging materials is sustained in all the other environmental impact and energy categories evaluated. The most effective measures to reduce the environmental footprint of the post-harvest stage involve: i) using reusable packaging materials; ii) reducing the transport range and using vehicles running on natural gas or hybrid technologies; iii) the incorporation of renewable energy to supply the factory; and iv) the utilization of the organic residues in higher value applications such as animal feeding. Implementing the measures proposed in this study would reduce the post-harvest CF of fresh vegetables by 90 %.

The Contribution of MCDM to SUMP: The Case of Spanish Cities during 2006-2021.

Sustainable Urban Mobility Plans (SUMP) are increasingly popular planning tools in cities with environmental issues where numerous actions are usually proposed to reduce pollution from urban transport. However, the diagnosis and implementation of these processes requires broad consensus from all stakeholders and the ability to fit them into urban planning in such a way that it allows the proposals to become realistic actions. In this study, a review of the sustainable urban mobility plans of 47 cities in Spain during the last 15 years has been carried out, analyzing both the diagnosis and proposal of solutions and their subsequent implementation. From the results obtained, a new framework based on a structured hybrid methodology is proposed to aid decision-making for the evaluation of alternatives in the implementation of proposals in SUMP. This hybrid methodology considers experts' and stakeholders' opinion and applies two different multi-criteria decision making (MCDM) methods in different phases to present two rankings of best alternatives. From that experience, an analysis based on the MCDM methods called 'Sequential Interactive Modelling for Urban Systems (SIMUS)' and weighted sum method (WSM) was applied to a case study of the city of Cartagena, a southeastern middle-size city in Spain. This analytic proposal has been transferred to the practical field in the SUMP of Cartagena, the first instrument of this nature developed after COVID-19 in Spain for a relevant city. The results show how this framework, based on a hybrid methodology, allows the development of complex decision mapping processes using these instruments without obviating the need to generate planning tools that can be transferred from the theoretical framework of urban reality.