Author(s): Ian Vázquez Rowe y otros
(Español) Life cycle assessment (LCA) has been widely applied in many different sectors, but the marine products and seafood segment have received relatively little attention in the past. In recent decades, global fish production experienced sustained growth and peaked at about 179 million tonnes in 2018. Consequently, increased interest in the environmental implications of fishery products along the supply chain, namely from capture to end of life, was recently experienced by society, industry and policy-makers. This timely review aims to describe the current framework of LCA and its application to the seafood sector that mainly focused on fish extraction and processing, but it also encompassed the remaining stages. An excess of 60 studies conducted over the last decade, along with some additional publications, were comprehensively reviewed; these focused on the main LCA methodological choices, including but not limited to, functional unit, system boundaries allocation methods and environmental indicators. The review identifies key recommendations on the progression of LCA for this increasingly important sustaining seafood sector. Specifically, these recommendations include (i) the need for specific indicators for fish-related activities, (ii) the target species and their geographical origin, (iii) knowledge and technology transfer and, (iv) the application and implementation of key recommendations from LCA research that will improve the accuracy of LCA models in this sector. Furthermore, the review comprises a section addressing previous and current challenges of the seafood sector. Wastewater treatment, ghost fishing or climate change, are also the objects of discussion together with advocating support for the water-energy-food nexus as a valuable tool to minimize environmental negativities and to frame successful synergies.
Open linkAuthor(s): César Portocarrero Rodríguez
(Español) Asesor: Gustavo Larrea
Tesis para optar el título de Licenciado en Ingeniería Civil
Resumen:
El agravamiento del estrés hídrico tanto en el sector urbano como en el rural motiva cada vez más a los tomadores de decisión a impulsar la explotación sostenible de este recurso. Para ello, se requiere conocer con certeza los emplazamientos con un mayor potencial de explotación. Para hacer frente a este problema sin recurrir a perforaciones directas, la presente investigación tiene como objetivo principal explorar el potencial hidrológico subterráneo del Perú correspondiente a acuíferos de baja profundidad mediante la aplicación de modelos de clasificación de bosques aleatorios y redes neuronales, dos algoritmos de aprendizaje automatizado. Esta rama de la inteligencia artificial permite generar modelos multidimensionales y con variables complejas sin efectuar presuposiciones estadísticas. Para explicar el potencial de agua subterránea, se recurren a variables topográficas, hidrológicas, geológicas, pedológicas y ambientales que influyen en diferente medida en la conductividad hidráulica subterránea y en la tasa de recarga de los acuíferos. Los resultados obtenidos indican que el mejor desempeño equiparable al estado del arte se obtiene para el modelo de bosques aleatorios (exactitud=0.77, puntaje F1=0.73, AUC=0.88) y que la construcción de modelos especializados en una región dada permite mejorar la capacidad de los modelos al reducir la varianza de los datos. Las variables más importantes en los modelos fueron: aspecto, densidad de drenaje, elevación, NDWI y precipitación. La principal limitación identificada en el desempeño de los modelos es la escasa cantidad y distribución irregular de los pozos de caudal conocido en el Perú, factor que parcializa el modelo hacia la costa, la región mejor documentada. El presente estudio sirve como marco referencial para la construcción de futuros modelos de aprendizaje automatizado una vez se amplíe el inventario público de pozos de agua subterránea o en caso privados introduzcan su propio inventario.
El código empleado para el procesamiento de variables geoespaciales se encuentra en https://code.earthengine.google.com/fe63cd6184b009824ed3c843fdc5544d.
El código utilizado para la construcción de modelos se encuentra registrado en Github en https://github.com/cesport/Tesis.
Aplicaciones para visualizar los resultados de manera interactiva están disponibles para computadoras en https://cesarportocarrero.users.earthengine.app/view/gwp-peru y dispositivos móviles en https://cesarportocarrero.users.earthengine.app/view/gwp-peru-movil.
Author(s): Ian Vázquez Rowe y otros
(Español) Food loss and waste (FLW) has become a central concern in the social and political debate. Simultaneously, using FLW as a bioenergy source could significantly contribute to closing the carbon cycle by reintroducing energy into the food supply chain. This study aims to identify best strategies for FLW management in each of the 17 regions in Spain, through the application of a Life Cycle Assessment. To this end, an evaluation of the environmental performance over time between 2015 and 2040 of five different FLW management scenarios implemented in a framework of (i) compliance and (ii) non-compliance with the targets of the Paris Agreement was performed. Results revealed savings in the consumption of abiotic resources in those regions in which thermal treatment has a strong presence, although their greenhouse gas (GHG) emissions in a scenario of compliance with climate change targets are higher. In contrast, scenarios that include anaerobic digestion and, to a lesser extent those applying aerobic composting, present lower impacts, including climate change, suggesting improvements of 20–60% in non-compliance and 20–80% in compliance with Paris Agreement targets, compared to the current scenarios.
Open linkAuthor(s): Ian Vázquez Rowe y otros
(Español) Beef production has notable environmental implications on a global scale. Paraguayan beef cattle farming is characterized by being developed mostly in pastures or grasslands, but recently the practice of finishing confined to feedlots has thrived. In this context, the aim of this study was to understand the environmental performance of a semi-intensive beef farm which involved in its production system both a pasture and a feedlot stage. A Life Cycle Assessment was carried out with a “cradle-to-farm gate” perspective and 1 kg of Live Weight as the functional unit. Primary data referring to cropping and livestock systems’ inputs and outputs were collected on site and a wide range of impact categories were evaluated. Beef cattle farming proved to be responsible for intensive greenhouse gas emissions (22.0 ± 3.9 kg CO2 eq ⋅ kg LW−1), especially when it occurs predominantly on pasture. The breeding phase is the one that weighs most on global warming potential within the rearing cycle. Since most animals are present in the pasture stage, this contributed highly to the impact categories influenced by animal-related emissions. The feedlot stage, despite its limited duration with respect to the overall rearing cycle, weighs significantly in the categories related to non-methane volatile organic compounds emissions, toxicity, land occupation and fuel consumption, especially because of feed production (both on- and off-farm). Moreover, this stage takes on a greater environmental load when considering the impacts of land use changes related to the consumption of purchased feed, even though its short duration reduces the relative variation given by land use changes inclusion. Some possible mitigation solutions were identified in the discussion, but further study is required into the implications of this topic and the exploration of different scenarios.
Open linkAuthor(s): Ian Vázquez Rowe, Gustavo Larrea Gallegos y (Español) otros
(Español) Current food consumption patterns must be revised in order to improve their sustainability. The nutritional, environmental, and economic consequences of these dietary patterns must be taken into consideration when diet guidelines are proposed. This study applied a systematic optimization methodology to define sustainable dietary patterns complying with nutritional, environmental, and economic issues. The methodology was based on a multi-objective optimization model that considered a distance-to-target approach. Although the three simultaneous objectives (maximal nutritional contribution, minimal greenhouse gas emissions, and minimal costs) could be divergent, the proposed model identified the optimal intake of each food product to achieve the maximal level of nutritional, environmental, and economic diets. This model was applied to six different eating patterns within the Spanish context: one based on current food consumption and five alternative diets. The results revealed that dietary patterns with improved nutritional profiles and reduced environmental impacts could be defined without additional costs just by increasing the consumption of vegetables, fruits, and legumes, while reducing the intake of meat and fish.
Open linkAuthor(s): Ian Vázquez Rowe y (Español) otros
(Español) Anaerobic digestion (AD) of organic waste, although widely practiced, may require suitable accompanying treatments to enhance the degradability of complex materials. Since these may require significant efforts in terms of energy and chemical demand, careful assessment of their overall environmental sustainability is mandatory to evaluate their full-scale feasibility. The study aims to represent the environmental profile of ultrasonication (US) applied as a post-treatment of anaerobic digestion of agro-industrial organic residues. There is an interest in the US treatment for the processing of complex organic materials prior to AD in order to enhance the hydrolysis of complex organic substrates and increase the biogas yield of the biological process. An attributional, process-based life cycle assessment (LCA) study was applied to quantify and compare the potential environmental impacts of an AD plant, the biogas utilization options as well as the different digestate processing alternatives grouped into a set of 16 scenarios. Based on the results, upgrading of biogas and bio-methane use as vehicle fuel instead of energy generation from CHP or fuel cell was recommended due to the lower impact on GWP. Similarly, composting was a suitable option to reduce environmental impacts compared to belt drying. From the uncertainty analysis, AD without US as post-treatment proves to be more sustainable in terms of GWP compared to when US is used, showing net savings in GHG emissions especially when upgrading of biogas is applied. The analysis provides useful indications to policy makers to define sustainable management alternatives for organic residues as well as identify the environmental advantages associated with biogas utilization and digestate treatment and disposal alternatives.
Open linkAuthor(s): Diana Ita Nagy, Ian Vázquez Rowe, Ramzy Kahhat Abedrabbo, Isabel Quispe Trinidad y (Español) otros
(Español) Purpose The aim of this review is to evaluate previous life cycle assessment (LCA) studies of first- and second-generation bioplastics, to understand the state of the art and the main problems addressed during the development of new bioplastics. Furthermore, it provides an overview on land use change (LUC) impacts accounted for, methodologies chosen, and the results obtained. Methods Studies related to the impact assessment of bioplastics and published between 2007 and 2018 were gathered. Five keyword strings were used to perform a wide search and select relevant LCA studies. The study aimed to analyze critical methodological aspects in LCA, in order to determine the most common choices made during biobased material analyses, as well as major limitations. Three filters were applied to select comparable studies, ending with a final number of 17 papers. Recommendations were obtained by comparing common practices performed by different authors with suggested best available practices mentioned in handbooks and guidelines. Interestingly, LUC metrics and impacts were, most of the time, neglected. Thus, a specific assessment and discussion was performed regarding the methods used to quantify LUC impacts, considering its importance during the production of biobased materials. Results and discussion The study discussed the main environmental problems linked to the development of new biomaterials. LCA of agricultural products or systems, when compared with fossil-based counterparts, is expected to show higher environmental impacts in categories directly affected by fertilizer use, occupied and transformed land, among others. Thus, studies that included additional impact categories besides global warming (e.g., eutrophication or acidification) concluded that biobased materials present higher impacts, recommending improvements in farming practices to improve their overall environmental profile. Moreover, this review gathered methodologies used to account for LUC impacts and the results obtained. The main constraint of including LUC impacts was the lack of a standardized methodology, as well as large uncertainties in existing methodologies. Conclusions Most studies concluded that improvements in farming practices might reduce the attributed environmental impacts with the reduction of the amount of land, fertilizer, pesticides, and water used. Studies computing LUC impacts agreed on the importance of including these impacts and concluded that greenhouse gas emissions of bioplastic production would increase, but in most cases would still be lower than the impact of their fossil-based counterparts. However, challenges remain when computing LUC impacts that need to be tackled when working with the available methodologies, including the collection of reliable inventory data (site-specific or regional data) and regionalized characterization factors.
Open linkAuthor(s): Ian Vázquez Rowe y (Español) otros
(Español) The COVID lockdown has affected food purchases and eating habits. In this regard, this short communication assesses the nutritional and environmental impacts of these changes during the COVID lockdown in Spain, by applying Life Cycle Assessment and an energy- and nutrient-corrected functional unit. Three environmental impacts were studied (Global Warming Potential, Blue Water Footprint and Land Use) and a total of seven weekly diet scenarios were designed: two pre-COVID diets for March and April in 2019 (MAR19, APR19), one COVID diet (COVID) and two alternative diets, one based on the National Dietary Guidelines (NDG) and another one on the Planetary Health Diet (PHD). Results show that the COVID diet had larger energy intake and lower nutritional quality, as well as higher environmental impacts (between 30 and 36%) than the pre-COVID eating patterns. Further research is needed to account for food affordability within this assessment, as well as to analyze how eating patterns will evolve after the COVID lockdown. Finally, the definition of short guidelines for sustainable food behaviors for future possible lockdowns is suggested, as well as the introduction of sustainable indicators within NDGs.
Open link