RESUMO
BACKGROUND: Assessing the trends in dietary GHGE considering the social patterning is critical for understanding the role that food systems have played and will play in global emissions in countries of the global south. Our aim is to describe dietary greenhouse gas emissions (GHGE) trends (overall and by food group) using data from household food purchase surveys from 1989 to 2020 in Mexico, overall and by education levels and urbanicity. METHODS: We used cross-sectional data from 16 rounds of Mexico's National Income and Expenditure Survey, a nationally representative survey. The sample size ranged from 11,051 in 1989 to 88,398 in 2020. We estimated the mean total GHGE per adult-equivalent per day (kg CO2-eq/ad-eq/d) for every survey year. Then, we estimated the relative GHGE contribution by food group for each household. These same analyses were conducted stratifying by education and urbanicity. RESULTS: The mean total GHGE increased from 3.70 (95%CI: 3.57, 3.82) to 4.90 (95% CI 4.62, 5.18) kg CO2-eq/ad-eq/d between 1989 and 2014 and stayed stable between 4.63 (95% CI: 4.53, 4.72) and 4.89 (95% CI: 4.81, 4.96) kg CO2-eq/ad-eq/d from 2016 onwards. In 1989, beef (19.89%, 95% CI: 19.18, 20.59), dairy (16.87%, 95% CI: 16.30, 17.42)), corn (9.61%, 95% CI: 9.00, 10.22), legumes (7.03%, 95% CI: 6.59, 7.46), and beverages (6.99%, 95% CI: 6.66, 7.32) had the highest relative contribution to food GHGE; by 2020, beef was the top contributor (17.68%, 95%CI: 17.46, 17.89) followed by fast food (14.17%, 95% CI: 13.90, 14.43), dairy (11.21%, 95%CI: 11.06, 11.36), beverages (10.09%, 95%CI: 9.94, 10.23), and chicken (10.04%, 95%CI: 9.90, 10.17). Households with higher education levels and those in more urbanized areas contributed more to dietary GHGE across the full period. However, households with lower education levels and those in rural areas had the highest increase in these emissions from 1989 to 2020. CONCLUSIONS: Our results provide insights into the food groups in which the 2023 Mexican Dietary Guidelines may require to focus on improving human and planetary health.
Assuntos
Gases de Efeito Estufa , México , Gases de Efeito Estufa/análise , Humanos , Estudos Transversais , Bebidas/estatística & dados numéricos , Dieta/estatística & dados numéricos , Dieta/tendências , Alimentos/estatística & dados numéricos , Efeito Estufa , Características da FamíliaRESUMO
In order to evaluate the level of sustainability of an integrated waste management system (IWMS), it is necessary to analyze the impact criteria. Therefore, the purpose of this study is to provide a model for IWMS optimization with the two goals of minimizing the cost and the emission of greenhouse gases of the entire system. Environmental and health problems caused by the lack of proper waste management include the increase in disease, increase in stray animals, pollution of air, water, land, etc. Therefore, it is very important to identify the indicators and improve the efficiency of the waste management system. In the present research, with descriptive-analytical approach, it has been tried to clarify and evaluate the effective indicators in two dimensions of production-segregation and collection-transportation, and find ways to improve the efficiency of the system. In this article, five waste management systems including, incineration, landfill without gas extraction system, plasma incineration, recycling and aerobic decomposition are introduced and their performance in energy production and emission reduction are compared. The results of the evaluation of the basic waste management system (b) show that the amount of pollution is equivalent to 850 kg CO2 per ton of waste. While the amount of emission in the fifth comprehensive management system is reduced to 450 kg CO2 per ton of waste. According to the results obtained in this study, in all the management systems presented, the process of burying waste in sanitary landfills has the greatest effect in increasing pollution. This means that the pollution caused by burying the waste in the sanitary landfill will be reduced with the construction of the gas extraction system and the plasma method and use in electricity production. Despite the increase in initial costs, using the right technology and using the right waste system based on the type of waste and waste recycling has an effect on the efficiency of the system.
Assuntos
Eliminação de Resíduos , Gerenciamento de Resíduos , Eliminação de Resíduos/métodos , Dióxido de Carbono , Efeito Estufa , Gerenciamento de Resíduos/métodos , IncineraçãoRESUMO
This study delves into the critical nexus between wastewater treatment, energy consumption, and greenhouse gas emissions. Wastewater treatment is a linchpin of sustainable development, yet its energy-intensive processes contribute significantly to greenhouse gas emissions. The research focuses on wastewater treatment plants (WWTPs) in Mexico City (CDMX) and the Metropolitan Area of Barcelona (AMB), exploring the disparities between a developed country and a developing country. The study examines how factors such as water treatment technologies and electricity sources influence carbon emissions. The AMB exhibits superior performance by treating all wastewater, cogenerating energy from the biomass contained in the wastewater and generating 10% fewer emissions, in stark contrast to CDMX, which does not capture the CH4 produced during water treatment, on top of only treating the water of 14% of the city's agglomeration. It underscores the critical implications of WWTP efficiency on climate change and progress toward UN Sustainable Development Goals. Given the limited attention to the Global South, this research serves as a vital contribution to the discourse on sustainability and development.
Assuntos
Gases de Efeito Estufa , Purificação da Água , Gases de Efeito Estufa/análise , Águas Residuárias , México , Efeito EstufaRESUMO
The Intergovernmental Panel on Climate Change (IPCC) indicates that the waste sector is a potential emitter of methane gas (CH4), which has a greenhouse effect up to 28 times greater than that of carbon dioxide (CO2). The management of municipal solid waste (MSW) generates greenhouse gases (GHG) directly through emissions from the process itself as well as indirectly through transportation and energy consumption. The objective of this study was to evaluate the GHG emissions contributed by the waste sector in the Recife metropolitan region (RMR) and to define mitigation scenarios to comply with the Brazilian Nationally Determined Contribution (NDC), a result of the Paris Agreement. To achieve this, an exploratory study was carried out, including a literature review, collection of data, estimation of emissions using the IPCC model (2006), and comparison between the values assumed by the country in 2015 and those estimated in the adopted mitigation scenarios. The RMR is composed of 15 municipalities, has an area of 3,216,262 km2 and a population of 4,054,866 inhabitants (2018), generating approximality 1.4 million t-year of MSW. It was estimated that, in the period from 2006 to 2018, 25.4 million tCO2e were emitted. The comparative analysis between the absolute values defined in the Brazilian NDC and the results from the mitigation scenarios showed that approximately 36 million tCO2e could be avoided through the disposal of MSW in the RMR, equivalent to a 52% reduction in emissions estimated for 2030, a percentage greater than the 47% reduction assumed in the Paris Agreement.
Assuntos
Gases de Efeito Estufa , Eliminação de Resíduos , Resíduos Sólidos/análise , Eliminação de Resíduos/métodos , Brasil , Dióxido de Carbono/análise , Efeito Estufa , Metano/análiseRESUMO
Most of the world's nations (around 130) have committed to reaching net-zero carbon dioxide or greenhouse gas (GHG) emissions by 2050, yet robust policies rarely underpin these ambitions. To investigate whether existing and expected national policies will allow Brazil to meet its net-zero GHG emissions pledge by 2050, we applied a detailed regional integrated assessment modelling approach. This included quantifying the role of nature-based solutions, such as the protection and restoration of ecosystems, and engineered solutions, such as bioenergy with carbon capture and storage. Our results highlight ecosystem protection as the most critical cost-effective climate mitigation measure for Brazil, whereas relying heavily on costly and not-mature-yet engineered solutions will jeopardise Brazil's chances of achieving its net-zero pledge by mid-century. We show that the full implementation of Brazil's Forest Code (FC), a key policy for emission reduction in Brazil, would be enough for the country to achieve its short-term climate targets up to 2030. However, it would reduce the gap to net-zero GHG emissions by 38% by 2050. The FC, combined with zero legal deforestation and additional large-scale ecosystem restoration, would reduce this gap by 62% by mid-century, keeping Brazil on a clear path towards net-zero GHG emissions by around 2040. While some level of deployment of negative emissions technologies will be needed for Brazil to achieve and sustain its net-zero pledge, we show that the more mitigation measures from the land-use sector, the less costly engineered solutions from the energy sector will be required. Our analysis underlines the urgent need for Brazil to go beyond existing policies to help fight climate emergency, to align its short- and long-term climate targets, and to build climate resilience while curbing biodiversity loss.
Assuntos
Efeito Estufa , Gases de Efeito Estufa , Agricultura/métodos , Ecossistema , Brasil , Gases de Efeito Estufa/análiseRESUMO
Brazil is the second-largest ethanol producer in the world, primarily using sugar cane as feedstock. To foster biofuel production, the Brazilian government implemented a national biofuel policy, known as RenovaBio, in which greenhouse gas (GHG) emission reduction credits are provided to biofuel producers based on the carbon intensities (CI) of the fuels they produce. In this study, we configured the GREET model to evaluate life cycle GHG emissions of Brazilian sugar cane ethanol, using data from 67 individual sugar cane mills submitted to RenovaBio in 2019/2020. The average CI per megajoule of sugar cane ethanol produced in Brazil for use in the U.S. was estimated to be 35.2 g of CO2 equivalent, a 62% reduction from U.S. petroleum gasoline blendstock without considering the impacts of land use change. The three major GHG sources were on-field N2O emissions (24.3%), sugar cane farming energy use (24.2%), and sugar cane ethanol transport (19.3%). With the probability density functions for key input parameters derived from individual mill data, we performed stochastic simulations with the GREET model to estimate the variations in sugar cane ethanol CI and confirmed that despite the larger variations in sugar cane ethanol CI, the fuel provided a robust GHG reduction benefit compared to gasoline blendstock.
Assuntos
Gases de Efeito Estufa , Saccharum , Gasolina , Efeito Estufa , Biocombustíveis , Brasil , EtanolRESUMO
The transition to a neutral carbon and sustainable urban water cycle requires improving eco-efficiency in wastewater treatment processes. To support decision-making based on eco-efficiency evaluations, reliable estimations are fundamental. In this study, the eco-efficiency of a sample of 109 WWTPs was evaluated using efficiency analysis tree method. It combines machine learning and linear programming techniques and therefore, overcomes overfitting limitations of non-parametric methods used by past research on this topic. Results from the case study revealed that optimal costs and greenhouse gas emissions depend on the quantity of organic matter and suspended solids removed from wastewater. The estimated average eco-efficiency is 0.373 which involves that the assessed WWTPs could save 0.32 /m3 and 0.11 kg of CO2 equivalent/m3. Moreover, only 4 out of 109 WWTPs are identified as eco-efficient which implies that the majority of the evaluated facilities can achieve substantial savings in operational costs and greenhouse gas emissions.
Assuntos
Gases de Efeito Estufa , Purificação da Água , Gases de Efeito Estufa/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias , Efeito EstufaRESUMO
Higher education institutions (HEIs) transfer skills and knowledge between industries, the government, and the public, playing a vital role at educating future leaders in creating a globally sustainable system. Therein, evaluating greenhouse gas emissions from an educational institute is the first step towards the proposed reduction targets at the local, national, and international levels. In this research, we report the first approximate carbon footprint calculation of emissions corresponding to scope 1, scope 2, and scope 3 emissions for the main urban campuses of Universidad Nacional de Colombia, Medellín, using the UNE-ISO 14064-1 and WRI/WBCSD GHG Protocol Corporate standard. The carbon footprint in 2019 was approximately 7250.52 tons CO2 eq, and 0.432 tons CO2 eq per person. Scope 1 emissions accounted for about 2.84% of the carbon footprint, while scope 2 and 3 emissions each contributed nearly 14% and 83%, respectively. The largest sources of greenhouse gas emissions were the transportation process (58.51%), the wastewater process (17.01%), followed by electricity consumption (14.03%), and the e-mails that are sent (6.51%). It is suggested some proposals and strategies for mitigating and reducing emissions. Colombian HEIs exhibit the lowest ton of CO2 eq. per person compared to the other HEIs. Several reasons explain this behavior across the document such as geographic location (climate and topography), cultural factors (consumption patterns and types of transportation), population size, typology (public or private), gross domestic product (GDP) of each country, and methodology implemented. Results cannot be extrapolated to the Colombian case for the differences in the local conditions; therefore, it is not possible to get solid conclusions on the CF behavior in the Colombian HEIs. In this research, we provide for the first time a carbon footprint calculation where the sociological, political, and geographic conditions not extrapolated representing a valuable contribution to the HEI's of the country. This research can be a benchmark in the carbon footprint calculation and a methodological contribution to HEIs in the country.
Assuntos
Pegada de Carbono , Gases de Efeito Estufa , Humanos , Gases de Efeito Estufa/análise , Colômbia , Universidades , Efeito EstufaRESUMO
Climate change is a major constraint on the sustainability of the humid tropics, maintaining ecosystem services, food production, and social functioning. Humid tropics play an essential role in C storage and greenhouse gas (GHG) emission reduction. Unfortunately, unplanned economic exploration, human occupation, and lack of knowledge of techniques to maintain ecosystem services negatively affect the humid tropics. In this study, we focused on the mechanisms of GHG emissions, C storage, and their mitigation strategies. This review indicated technologies that can be adopted by farmers in humid tropics to maintain or increase their capacity to store C stocks and reduce GHG emissions. The adoption of climate-smart agriculture technologies and the regulation of ecosystem services markets will accelerate the progress of preserving the humid tropics. Improved management practices, such as proper N fertilizer management and the introduction of N2-fixing legumes, can increase soil C sequestration, providing economic and environmental trade-offs associated with these management strategies. Public and private investments toward knowledge dissemination and technology adoption regarding GHG emissions reduction and soil C storage are needed to allow humid tropics to maintain their critical function of generating environmental and societal benefits.
Assuntos
Gases de Efeito Estufa , Agricultura , Brasil , Carbono , Sequestro de Carbono , Ecossistema , Fertilizantes , Pradaria , Efeito Estufa , Gases de Efeito Estufa/análise , Humanos , SoloRESUMO
Food systems (FSs) emit ~ 20 GtCO2e/y (~ 35% of global greenhouse gas emissions). This level tends to raise given the expected increases in food demands, which may threaten global climate targets. Through a rapid assessment, evaluating 60+ scenarios based on existing low-emission and carbon sequestration practices, we estimate that intensifying FSs could reduce its emissions from 21.4 to - 2.0 GtCO2e/y and address increasing food demands without relying on carbon offsets (e.g., related to afforestation and reforestation programs). However, given historical trends and regional contexts, a more diverse portfolio of practices, including diet shifts and new-horizon technologies, will be needed to increase the feasibility of achieving net-zero FSs. One likely pathway consists of implementing practices that shift food production to the 30th-percentile of least emission-intensive FSs (~ 45% emissions reduction), sequester carbon at 50% of its potential (~ 5 GtCO2e/y) and adopt diet shifts and new-horizon technologies (~ 6 GtCO2e/y). For a successful transition to happen, the global FSs would, in the next decade (2020s), need to implement cost-effective mitigation practices and technologies, supported by improvements in countries' governance and technical assistance, innovative financial mechanisms and research focused on making affordable technologies in the following two decades (2030-2050). This work provides options and a vision to guide global FSs to achieving net-zero by 2050.
Assuntos
Sequestro de Carbono , Gases de Efeito Estufa , Carbono , Clima , Alimentos , Efeito EstufaRESUMO
Waste management is a critical policy towards the reduction of environmental impacts to air, soil and water. Many Latin American countries, however, lack a correct waste management system in many cities and rural areas, leading to the accumulation of unmanaged waste in illegal or unregulated dumpsites. The case of Peru is of interest, as it hosts 5 of the 50 largest dumpsites in the world. An erratic waste management compromises climate actions for Peru to commit with the Paris Agreement, as no correct closure systems are established for these dumpsites. Therefore, the main objective of this study is to assess the contribution of the past and present biodegradable waste produced and disposed of in the most critical open dumpsters to the overall annual greenhouse gas (GHG) emissions of Peru using the IPCC model. Thereafter, the climate change mitigation potential of possible dumpsite closure strategies based on a selection of technologies, including economic feasibility, were estimated. Results show that cumulative GHG emissions in 2018 for the 24 critical dumpsites evaluated added up to 704 kt CO2 eq. and a cumulative value of 4.4 Mt CO2 eq. in the period 2019-2028, representing over 40 % of solid waste emissions expected by 2030. Mitigation potentials for these emissions tanged from 91 to 970 kt CO2 eq. in the ten-year period depending on the mitigation strategies adopted. The costs of these strategies are also discussed and are expected to be of utility to complement Peru's waste management commitments in the frame of the Paris Agreement.
Assuntos
Gases de Efeito Estufa , Eliminação de Resíduos , Dióxido de Carbono/análise , Mudança Climática , Efeito Estufa , Peru , Eliminação de Resíduos/métodos , Resíduos Sólidos/análiseRESUMO
A pandemia de COVID-19 deu ao mundo uma imagem clara do que é uma crise multidimensional em escala planetária, revelando o papel central que ocupa o setor de saúde e as profundas desigualdades no acesso aos cuidados em saúde que existem entre os diferentes países, e dentro de cada um deles. Melhorar os efeitos ambientais do setor e reduzir as emissões de gases de efeito estufa pode não apenas melhorar a saúde de todos, mas também reduzir os custos com os cuidados em saúde. O setor de saúde de cada país libera direta e indiretamente gases de efeito estufa ao fornecer seus serviços e ao comprar produtos, serviços e tecnologias em uma cadeia de fornecimento de carbono intensivo. Educar os profissionais de saúde mais profundamente sobre os efeitos das mudanças climáticas pode levar a práticas clínicas mais sustentáveis, melhorando os resultados para os pacientes e fornecendo um impulso substancial para aumentar os esforços para reduzir as emissões de carbono. O setor da saúde deve assumir a responsabilidade por sua pegada climática respondendo à crescente emergência climática, não apenas prestando assistência aos doentes, feridos ou moribundos como resultado da crise climática e suas causas, mas também fazendo a prevenção primária e reduzindo drasticamente suas próprias emissões.
The COVID-19 pandemic has painted a clear picture of what a multidimensional planetary crisis is, revealing the central role played by the health sector and the deep inequalities in access to health care that exist between and within each country. Decreasing the environmental effects of the health sector and reducing greenhouse gas emission may not only improve people's health, but also reduce health care costs. The health care sectors around the world directly and indirectly release greenhouse gases by providing their services and purchasing products, services, and technologies within a carbon-intensive supply chain. Further educating health care professionals about the effects of climate change may lead to more sustainable clinical practices, improving patient outcomes and providing substantial impetus to increased efforts to reduce carbon emission. The health sector must take responsibility for its climate footprint by responding to the growing climate emergency not only by assisting the sick, injured, or dying from the climate crisis, but also by doing primary prevention and drastically reducing its own carbon emission.
Assuntos
Humanos , Mudança Climática , Saúde Ambiental , COVID-19 , Pacientes , Prevenção Primária , Carbono , Saúde , Custos de Cuidados de Saúde , Clima , Pessoal de Saúde , Efeito Estufa , PubMed , Gases de Efeito Estufa , Pandemias , Acessibilidade aos Serviços de SaúdeRESUMO
Several discussions have arisen about energy from hydroelectric plants being considered clean energy and its reservoirs have been investigated due to the large emission of greenhouse gases (GHG), such as carbon dioxide, methane, and nitrous oxide. The present work shows a statistical study of the diffusive CO2 emissions before the formation of the reservoir of the hydroelectric power plant (HPP) of SINOP, Brazil. The association between emissions collected at the surface (water-air) and at the bottom of the reservoir (sediment-water) was investigated during four data collection campaigns, carried out from November 2017 to September 2018. This study aims to compare the effect of reservoir depth on the diffusive flow of CO2 at 34 collection points. The variable depth analyzed was defined from points collected on the surface and bottom of the reservoir. The objective is to detect whether different periods of time and whether the depth of the reservoir have a direct impact on the behavior of diffusive CO2 emissions. As the measurements of the observational unit are repeatedly observed, there is a multilevel structure, individuals are independent of each other, but there is an intra-individual correlation. Considering this data configuration, an estimation of generalized equations (GEE) was performed, which is a technique that estimates the intra-individual correlation matrix and thus produces estimates for the parameters of the generalized regression models (Generalized Regression Models - GLM) that are not biased. The study showed that the average diffusive CO2 emissions are higher on the reservoir surface. The study also found that, on average, there are more emissions during the rainy season in the region than during the dry season.
Assuntos
Dióxido de Carbono , Monitoramento Ambiental , Brasil , Dióxido de Carbono/análise , Efeito Estufa , Humanos , Metano/análise , ÁguaRESUMO
Fusarium oxysporum is an aggressive phytopathogen that affects various plant species, resulting in extensive local and global economic losses. Therefore, the search for competent alternatives is a constant pursuit. Quinolizidine alkaloids (QA) are naturally occurring compounds with diverse biological activities. The structural diversity of quinolizidines is mainly contributed by species of the family Fabaceae, particularly the genus Lupinus. This quinolizidine-based chemo diversity can be explored to find antifungals and even mixtures to address concomitant effects on F. oxysporum. Thus, the antifungal activity of quinolizidine-rich extracts (QREs) from the leaves of eight greenhouse-propagated Lupinus species was evaluated to outline promising QA mixtures against F. oxysporum. Thirteen main compounds were identified and quantified using an external standard. Quantitative analysis revealed different contents per quinolizidine depending on the Lupinus plant, ranging from 0.003 to 32.8 mg/g fresh leaves. Bioautography showed that all extracts were active at the maximum concentration (5 µg/µL). They also exhibited >50% mycelium growth inhibition. All QREs were fungistatic except for the fungicidal QRE of L. polyphyllus Lindl. Angustifoline, matrine, 13α-hydroxylupanine, and 17-oxolupanine were ranked to act jointly against the phytopathogen. Our findings constitute reference information to better understand the antifungal activity of naturally afforded QA mixtures from these globally important plants.
Assuntos
Antifúngicos/farmacologia , Lupinus/química , Extratos Vegetais/farmacologia , Quinolizidinas/farmacologia , Antifúngicos/química , Cromatografia Gasosa-Espectrometria de Massas , Efeito Estufa , Lupinus/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Quinolizidinas/químicaRESUMO
Moving to a more sustainable and low-carbon footprint urban water cycle is essential in the light of climate change. In this paper, we estimate the implicit cost of reducing greenhouse gas (GHG) emissions for several English and Welsh water companies from 2013 to 2019. Using econometric techniques, we compute the shadow prices of direct and indirect CO2 emissions associated with the provision of drinking water. This methodological approach also allows us to investigate the impact of a set of environmental variables on the costs of water companies and therefore on the costs of reducing GHG emissions. We then compute the returns to scale, technical change, and technical efficiency of the water companies. The empirical results show the following: (1) the average shadow price of CO2 across years was 0.114 £/kgCO2, which means that the English and Welsh water industry needs to spend an extra £0.114 in operating expenditure to prevent the emission of one kilogramme of CO2; (2) the cost of reducing GHG emissions is very variable among water companies and across years; (3) water taken from boreholes and average pumping head increases cost requirements and therefore the inefficiency of water companies; and (4) the water industry may lower its production costs and thus the costs of reducing GHG emissions by improving its daily operations and adopting new technologies. From a policy perspective, this study evidences that in the English and Welsh water industry, a market-based approach may be more suitable to reduce GHG emissions than a carbon tax policy.
Assuntos
Gases de Efeito Estufa , Eficiência , Efeito Estufa , Gases de Efeito Estufa/análise , Indústrias , Água , Abastecimento de ÁguaRESUMO
There is a growing need of sustainable solutions for balancing agricultural production with the reduction of its environmental impacts. The rapid increase in sugarcane cultivation and the progressive conversion of pre-harvest burning (BH) to green harvest (GH) have brought into debate the contribution of agricultural sector to the greenhouse gas (GHG) mitigation. This study focused on the estimated GHG emission from sugarcane cultivation during years in which sugarcane areas in southern Brazil expanded and passed throughout an important transition, from 2006 to 2012, when harvest adopted was changed from burned to not-burned based. Sugarcane management and harvest were mapped through visual interpretation of Landsat-type satellite images, and the areas under sugarcane cultivation were distinguished according to each agricultural phase and harvest regime (i.e., manual harvest with burning vs. green mechanized harvest). Based on a broad data review and applying the IPCC (2006) methodologies, the results were expressed in terms of kilograms of carbon dioxide equivalent (kg CO2eq ha-1). Avoiding burn prior to harvest, even during expansion of sugarcane areas, promoted a mean reduction of GHG emission from 901 to 686 kg CO2eq ha-1 relative to harvest phase (24% lower) and an increase from 1418.3 to 1507.9 kg CO2eq ha-1 related to the ratoon maintenance phase (6% higher). Analyzing the total GHG emission per unit of cultivated sugarcane area (hectare), it was observed a decrease from 2275 to 2034 kg CO2eq ha-1 (11% reduction). The gradual transition of pre-harvest burning on that period has contributed to the reduction of GHG emission associated with sugarcane production being an important step towards GHG mitigation while still providing more sustainable sugar and ethanol production in southern Brazil.
Assuntos
Gases de Efeito Estufa , Saccharum , Agricultura , Brasil , Efeito EstufaRESUMO
Many regions around the world are suffering from water stress, and desalinated water and recycled water are seen as alternatives for meeting the water demand. However, high energy consumption and associated greenhouse gas emissions are some of the main environmental impacts. This is notable for many arid and semi-arid countries where desalination and water recycling are considered options for ensuring water resources availability. This research presents the incorporation of the quantification of greenhouse gas emissions generated during the operation of desalination and wastewater treatment plants in the assessment of water stress levels using the water stress indicator adopted by the 2030 Agenda for Sustainable Development. Chile was chosen as a case study, as it is a country where there is a considerable difference between the availability of conventional water sources and the water demand, and the electrical grid is fed mainly by fossil fuels. The methodology proposed allows calculating the indirect greenhouse gas emissions due to electrical consumption for the operation of desalination and wastewater treatment plants, and the direct greenhouse gas emissions coming from biological processes used in wastewater treatment plants. The results showed that Chilean arid climate zones will not experience water stress in the future at the regional level, mainly because of the installation of several desalination plants by 2030. Meanwhile, recycled water from the urban sector will slightly contribute to the reduction in the level of water stress in almost all Chilean regions by 2030. Moreover, desalination and wastewater treatment plant will contribute only between 0.34% and 0.75% of total greenhouse gas emitted in Chile by 2030. Therefore, the operation of these industrial systems for facing water scarcity problems in northern and central zones of Chile is a suitable alternative because it does not generate large environmental problems.
Assuntos
Gases de Efeito Estufa , Purificação da Água , Chile , Desidratação , Efeito Estufa , Humanos , Água do Mar , Águas ResiduáriasRESUMO
Human health has been negatively impacted by the difficult environmental conditions produced by climate change. The health industry, paradoxically, generates a carbon footprint (CF) that drives climate change and represents 9.8% of the greenhouse gas (GHG) emissions in the United States (2013) and 6.3% of CF in England (2017). A considerable portion of these emissions comes from the clinical practice of anesthesia. Anesthetic gases present global warming potentials (GWPs) of up to 3,714 times higher than CO2 throughout their life cycles, from their manufacture and use to their disposal. In this context, this review compiled and assessed the environmental impacts of the anesthetic strategy in clinical practice, making use of the life cycle analysis tool. This review describes how the anesthetic technique has a major impact on CF, through the emission of GHG expressed through tools such as the GWP. As an example, at the manufacturing stage, the GWP of halogenated gases is up to 2,540 kg COeq versus 21 kg COeq for Propofol. This and other variables determine the contribution of the anesthetic technique in the emission of GHG. Finally, this review aims to help health care providers make informed decisions when considering the CH and sustainability of each anesthetic technique.
La salud de las personas se ha visto afectada negativamente debido a las difíciles condiciones ambientales producidas por el cambio climático. La industria sanitaria, paradójicamente, genera una huella de carbono (HC) que impulsa el cambio climático y representa el 9,8% de las emisiones de gases de efecto invernadero (GEI) en Estados Unidos (2013) y el 6,3% de la HC en Inglaterra (2017). Una parte considerable de estas emisiones proviene de la práctica clínica de la anestesia. Los gases anestésicos presentan potenciales de calentamiento global (GWP) de hasta 3.714 veces superiores al CO2 a lo largo de su ciclo de vida, desde su fabricación y uso, hasta su eliminación. En este contexto, esta revisión compiló y evaluó los impactos ambientales de la estrategia anestésica en la práctica clínica, haciendo uso de la herramienta de análisis del ciclo de vida. Esta revisión describe como la técnica anestésica presenta un impacto de magnitud en la HC, a través de la emisión de GEI expresado a través de herramientas como es el GWP. Como ejemplo, en el caso de los gases halogenados estos pueden generar hasta 2.540 kg COeq en su etapa de fabricación frente a 21 kg COeq para el Propofol. Esta y otras variables determinan el aporte de la técnica anestésica en la emisión de GEI. Finalmente, esta revisión tiene como objetivo ayudar al cuerpo médico a tomar decisiones informadas al considerar la HC y la sustentabilidad de cada técnica de anestesia.
Assuntos
Humanos , Efeito Estufa , Aquecimento Global , Pegada de Carbono , Monitoramento Biológico , Anestesia , AnestesiologiaRESUMO
Growing municipal solid waste (MSW) generation is a source of environmental, economic, and social concerns, especially in developing world megacities where poor MSW practices prevail. Mexico City (CDMX), one of the world's largest megacities, daily produces â¼ 13,073 Mg of MSW whose management poses a tremendous challenge to local authorities and calls for additional research to conceive sound MSW strategies. This study evaluates the fossil energy use, GHG emissions, resource recovery, and economic cost dimensions of current and five alternative MSW paths in CDMX to compare their performance and identify more sustainable MSW practices for the megacity. Impacts and benefits from the MSW paths were modeled using 2018 MSW generation data, information supplied by local authorities, and literature values. Current MSW path consumes â¼ 387 MJfossil, generates â¼ 501 kg-CO2e, and costs â¼ 57 USD2018 per Mg of MSW managed while it only valorizes < 33% of total MSW mostly via informal truck-picking. The alternative MSW paths considerably reduce GHG emissions (â¼129-360 kg-CO2e/Mg) and enhance MSW valorization (â¼47-88%) though, they entail higher fossil energy consumption (447-582 MJfossil/Mg) and, in general, higher cost expenditures (43-208 USD2018/Mg). Heavy reliance on landfilling, large GHG emissions, and low MSW valorization make current MSW path in CDMX unsustainable. Incineration-based MSW paths perform better in most aspects evaluated but their high costs seem prohibitive. Results suggest MSW paths featuring open windrow composting, mechanical-biological pre-treatment, material recovery facilities, and refuse-derived fuel production may be more appropriate to improve the sustainability of CDMX MSW management.