Autor(es): Ian Vázquez Rowe y Namy Espinoza Orias, Christian John Reynolds, Alexi Sara Ernstoff, Karen Cooper, Rubén Aldaco.
Action on reducing food loss and waste (FLW) is imperative to mitigate the impacts of climate change worldwide and to achieve the Sustainable Development Goals on food security, hunger eradication, and sustainable production and consumption. Next year (2022) will be the UN summit of food systems (“the COP for food”), as articles in this special issue illustrate, FLW will stay as one of the major levers to pull for food system transformation and sustainable consumption.
Ir al enlaceAutor(es): Ian Vázquez Rowe, Kurt Ziegler Rodríguez, Ramzy Kahhat Abedrabbo y María Margallo, Rubén Aldaco
Peru struggles to upgrade its waste management, with landfilling only just overtaking open dumpsters as the main disposal method. Despite the benefits of this transition, including reduced environmental impacts to water and soil, previous studies demonstrated that greenhouse gas (GHG) emissions may increase if adequate levels of technological sophistication are not implemented. Considering that 58% of municipal solid waste (MSW) is organic, it seems plausible that a relevant portion of emissions can be linked directly to food loss and waste (FLW) management. This study aims to determine the GHG emissions mitigation potential in FLW compared to the current baseline scenario in 24 Peruvian cities, by modelling alternative technologies to treat organic MSW. Life cycle modelling was performed using the waste-LCA software EASETECH. Five treatment scenarios were modelled: i) open dumping; ii) landfilling with no gas treatment; iii) landfilling with landfill gas treatment; iv) landfilling with energy recovery; and, v) anaerobic digestion. GHG emissions of FLW generation proved to be substantially higher than those for FLW treatment. However, if sophisticated technologies are implemented in FLW treatment, an annual reduction of up to 1.56 Mt CO2eq could be attained. Moreover, despite the health and environmental benefits of a transition to optimized diets, in which, for example, meat consumption is reduced and vegetables are boosted, an important increase in FLW and, therefore, an increase in GHG emissions in the treatment phase is shown. However, if certain technologies, such as energy recovery or anaerobic digestion, were implemented, most carbon losses would be avoided.
Ir al enlaceAutor(es): Ian Vázquez Rowe y Daniel Hoehn, Rubén Aldaco, María Margallo, Jara Laso, Israel Ruiz-Salmón, Francisco José Amo-Setién, Rebeca Abajas-Bustillo, Carmen Sarabia, Ainoa Quiñones, Alba Bala, Laura Battle-Bayer, Pere Fullana-i-Palmer
There is a growing debate surrounding the contradiction between an unremitting increase in the use of resources and the search for environmental sustainability. Therefore, the concept of sustainable degrowth is emerging aiming to introduce in our societies new social values and new policies, capable of satisfying human requirements whilst reducing environmental impacts and consumption of resources. In this framework, circular economy strategies for food production and food loss and waste management systems, following the Sustainable Development Goals agenda, are being developed based on a search for circularity, but without setting limits to the continual increase in environmental impacts and resource use. This work presents a methodology for determining the percentage of degrowth needed in any food supply chain, by analyzing four scenarios in a life cycle assessment approach over time between 2020 and 2040. Results for the Spanish case study suggested a degrowth need of 26.8% in 2015 and 58.9% in 2040 in order to achieve compliance with the Paris Agreement targets, highlighting the reduction of meat and fish and seafood consumption as the most useful path.
Autor(es): Ramzy Kahhat Abedrabbo, Ian Vázquez Rowe, André Torre García, Eduardo Parodi Gonzales Prada
The centralization-decentralization dichotomy in wastewater treatment management has been a recurrent topic of discussion in the urban context. The escalation of environmental hazards linked to increasing mismanaged wastewater flows in emerging or developing cities has vivified this conundrum. It is argued that there is a wide range of parameters to identify the optimal level of centralization-decentralization that must be implemented. In many cases, this prevents decision-makers from having a clear picture of the most appropriate management choices that must be undertaken. Hence, the main objective of the current discussion consists of an in-depth comparison between centralized wastewater treatment systems and decentralized systems with source separation in urban environments of the Global South. Moreover, a set of actions that should be considered in order to upgrade wastewater treatment systems amidst the existence of numerous economic, social and environmental constraints are analyzed. Considering the constraints of megacentralization as a preferred option, we argue that decision-makers should restrain from entering a centralization-decentralization dichotomy, seeing the process as a gradient between the two concepts. In fact, we advocate combining the benefits of each of the two perspectives to generate an adaptive management, site-specific solution for urban environments. For this, the inclusion of quantitative management tools, such as life-cycle environmental or cost management methodologies, in multi-objective optimization models, constitutes an interesting path forward towards fostering comprehensive policy support.
Ir al enlaceAutor(es): Ian Vázquez Rowe, Diana Ita Nagy, Ramzy Kahhat Abedrabbo
Plastic waste has arisen as a worldwide environmental concern, becoming ubiquitous in all marine compartments. Microplastics (MPs) are an important fraction of this accumulation, due to direct emissions from the technosphere or fragmentation of macroplastic waste. Consequently, the aim of this letter is to analyze the effects of microplastics on fishing and aquaculture, identifying the links with food safety and sustainability. Current studies have observed multiple potentially damaging effects of microplastics on marine biota, mainly at lower trophic levels. It is plausible to assume that fishing stocks and aquaculture systems will suffer setbacks due to these damages. However, additional research is needed to understand the potential effects on human health, especially considering that smaller microplastics and nanoplastics, for which data is very scarce, are the particles most likely to be absorbed by human tissues.
Ir al enlaceAutor(es): Ian Vázquez Rowe, Kurt Ziegler Rodríguez y Lorena Espinoza Pérez, Andrea Teresa Espinoza Pérez, Óscar C. Vásquez
Municipal solid waste (MSW) management is an important challenge in developing and emerging countries, where two realities co-exist. On the one hand, their metropolitan cities exhibit an integrated MSW system with a specialized fleet for the collection and landfills for the final disposal, concentrating on environmental initiatives such as municipal recycling programs. On the other hand, their regional cities show an MSW system based on adapted transports for collection and open dumps for final disposal. Besides, they face other environmental problems due to local conditions. This research proposes a life cycle assessment (LCA) approach to close the gap between these two realities. In particular, we study the city of Valdivia (Chile), one of the main regional capitals of South America, which shares similarities with other southern regional cities in the Global South. This city disposes 95% of its MSW in open dumps and presents one of the highest environmental pollution rates in Latin America. We analyze the greenhouse gas (GHG) emissions and energy performance of six scenarios, seeking a solution for these problems. The results obtained show that a waste-to-energy scenario would generate savings of GHG emission and particulate matter, reaching 11.3% and 21.8%, respectively. Using our LCA approach, we can provide environmental evidence to highlight the importance of improving MSW management in regional cities, closing the gap with MSW management in metropolitan cities, and contributing to national targets such as United Nations Sustainable Development Goals and Nationally-Determined Contributions.
Ir al enlaceAutor(es): Ian Vázquez Rowe y Sandra Santa-Cruz, Cristina Córdova-Arias, Xavier Brioso
Motivation and problem definition
A large number of public buildings designed with obsolete criteria are at high seismic risk and in need of structural rehabilitation. The task of selecting the optimal strategy poses important challenges for decision-makers due to the variety of intervention options and the fact that the construction sector is perceived to be one of the most corrupt in the economy.
Objective
Given that transparency is an efficient anti-corruption strategy, a protocol is proposed for decision-making in seismic rehabilitation projects of public infrastructure that incorporates criteria which serve to increase transparency in the project development.
Methods
Firstly, the literature was reviewed to describe current practices and regulations linked to decision-making in seismic rehabilitation/retrofitting of buildings. Secondly, relevant criteria that should be taken into account to favor transparency in decision-making were proposed. Thirdly, these criteria were integrated into a protocol that uses information and communication technologies (ICTs), Building Information Modeling (BIM), and collaborative methodologies that involve all stakeholders that will participate in the decision-making process. Finally, the protocol was applied to a real decision-making case study for the selection of alternatives for large-scale reinforcement of state schools in the city of Lima.
Results
The criteria of auditability or ease of control of the construction process is well regarded by stakeholders as a mechanism to increase transparency. Including these transparency criteria could influence the selection of reinforcement alternatives, especially if the profile of stakeholders is environmentally-oriented. The sensitivity analysis confirmed the dependency of the selection on the decision-maker profile.
Autor(es): Patrick Flores Velarde
Asesores: Ian Vázquez y Félix Cabrera
Las lagunas sísmicas, en el borde oeste del Perú datan de hace poco más de 130 años, lo cual implica que edificaciones de concreto armado no han sido sometidas a movimientos bruscos del suelo. La norma actual local y la de otros países tienen como finalidad la protección de la edificación ante un solo nivel de amenaza sísmica. Por tal razón la necesidad de estudiar nuestras edificaciones bajo diferentes niveles de amenaza sísmica es un objetivo del presente trabajo. El estudio consistió en diseñar y evaluar un edificio de cuatro niveles ubicado en la costa peruana cimentado sobre buen suelo, con una planta rectangular de 33x22m y columnas separadas a ejes por 5.5m. Para diseñar la edificación se empleó el código peruano y la evaluación se basó en los criterios propuestos por el Comité Visión 2000 del SEAOC. En cuanto a la herramienta de análisis, y por ende, de estimación de respuesta de la estructura, se usaron las técnicas del análisis no lineal, mediante espectros de capacidad y demanda. La etapa de pre-dimensionamiento resultó en columnas y vigas de dimensiones, 40x40cm y 25x50cm, respectivamente, permitiendo una deriva máxima de 1% para un evento sísmico de 500 años de período de retorno. De los resultados, se estimó una ductilidad promedio, para la estructura, de 4.6 y sobrerresistencia de 1.5, ambos ítems con respecto a la fluencia efectiva. Además, se alcanzaría un valor de 2.5 de sobrerresistencia con respecto al colapso. Bajo los niveles de amenaza sísmica, la estructura presentaría ligeras incursiones en el rango inelástico, específicamente para sismos raros y ocasionales, en ambas direcciones. Para el nivel de amenaza extremo, esto es, sismos raros, la estructura llegaría un poco más allá del inicio de la zona de colapso en ambas direcciones. El estudio se extendió para edificaciones de 3, 5, 6 y 7 pisos, permitiendo obtener tendencias de comportamiento, resultando, muchas de ellas, satisfactorias. Ante los resultados del trabajo realizado, se puede concluir en permitir una deriva máxima de 1% para edificios regulares, lo que conlleva a menores dimensiones de las columnas.
Tesis para optar el título de Licenciado en Ingeniería Civil
