Desempenho energético e pegada de carbono de um sistema de esgotamento sanitário centralizado no nordeste brasileiro / Energy performance and carbon footprint of a centralized sewage system in northeastern Brazil

RESUMO O objetivo do trabalho foi avaliar a operação e manutenção de um sistema de esgotamento sanitário centralizado, composto de três subsistemas, que atende 367 mil habitantes no Nordeste do Brasil. A avaliação do ciclo de vida considerou um inventário amplo de operação e manutenção do sistema de esgotamento sanitário com as redes de coleta, estações de tratamento de esgoto, disposição do esgoto tratado no corpo hídrico e gestão do lodo. O arranjo tecnológico das estações de tratamento de esgoto avaliadas incluiu o reator do tipo upflow anaerobic sludge blanket, seguido de lagoa aerada e lagoa de polimento em um subsistema, e upflow anaerobic sludge blanket seguido de reator de lodo ativado por aeração prolongada em dois subsistemas. O desempenho energético utilizou o método de demanda de energia acumulada e a pegada de carbono empregou o método de potencial de aquecimento global de 100 anos do Painel Intergovernamental sobre Mudanças Climáticas. O sistema de esgotamento sanitário avaliado demandou 5,12 MJ·m−3 e emitiu 4,08 kg CO2eq·m−3. As maiores contribuições do sistema de esgotamento sanitário avaliado foram a eletricidade, com 62% da demanda energética, e as emissões diretas para o ar, com 94% da pegada de carbono, sendo as emissões dos reatores upflow anaerobic sludge blanket com 76% da pegada de carbono. A identificação dos aspectos e impactos ambientais do sistema de esgotamento sanitário avaliado apoia a inovação tecnológica e gerencial para otimizar o desempenho energético e mitigar as emissões de gases de efeito estufa.

ABSTRACT This aim of this work was to evaluate the operation and maintenance of a centralized wastewater treatment system, composed of three subsystems, which serves 367 thousand inhabitants in northeastern Brazil. The life cycle assessment considered a comprehensive inventory of the wastewater treatment system operation and maintenance with the collection networks, wastewater treatment plants, disposal of the treated wastewater in the water body and sludge management. The technological arrangement of the evaluated wastewater treatment plants included the Upflow Anaerobic Sludge Blanket reactor, followed by aerated and polishing ponds in one subsystem, and Upflow Anaerobic Sludge Blanket followed by extended aeration activated sludge in two subsystems. The energy performance used the cumulative energy demand method and the carbon footprint used the global warming potential method for 100 years of the Intergovernmental Panel on Climate Change. The evaluated wastewater treatment system presented 5.12 MJ·m−3 and 4.08 kg CO2eq·m−3. The largest contribution of the evaluated wastewater treatment system was the electricity use with 62% of the energy demand and direct emissions to the air with 94% of the carbon footprint, being direct emissions from Upflow Anaerobic Sludge Blanket reactors with 76% of the carbon footprint. The identification of environmental aspects and impacts of the evaluated wastewater treatment system supports technological and management innovations to optimize its energy performance and mitigate greenhouse gases emission.

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La crisis climática es una enorme amenaza para la salud humana. La evidencia que el cambio climático está ocurriendo es abrumadora, impulsado por actividades humanas que aumentan los gases de efecto invernadero en la atmósfera. Los inhaladores de dosis medidas presurizados utilizaban propulsores de clorofluorocarbonos. Los propulsores de clorofluorocarbonos fueron prohibidos debido a su gran impacto en el agotamiento de la capa de ozono. El protocolo de Montreal, introducido para proteger la capa de ozono, estableció una eliminación planificada de los clorofluorocarbonos, reemplazándolos con los hidrofluorocarbonos que ahora se utilizan en los inhaladores de dosis medidas presurizados. Si bien los hidrofluorocarbonos no agotan la capa de ozono, son potentes gases de efecto invernadero tienen un potencial de calentamiento global muchas veces mayor que el del dióxido de carbono. El sector de la salud es un contribuyente significativo a las emisiones de gases de efecto invernadero a nivel mundial. Los aumentos de la temperatura global ya están teniendo un impacto significativo en nuestro clima. La lucha contra el cambio climático se ha descrito como la mayor oportunidad de salud pública del siglo XXI. Para reducir el impacto de los inhaladores en el cambio climático, hay varias opciones disponibles, incluidas el reciclaje de los inhaladores, el uso de dispositivos alternativos, reducir la cantidad del propulsor por dosis o usar un propulsor con un potencial de calentamiento global menor. Los profesionales sanitarios tenemos el deber de proteger y promover la salud de los pacientes y emprender acciones para disminuir los peores efectos del cambio climático. Se deben hacer todos los esfuerzos posibles para minimizar la emisión de gases de efecto invernadero si queremos proteger a las generaciones actuales y futuras.

The climate crisis is a massive threat to human health. The evidence that climate change is happening, driven by human activities which increase atmospheric greenhouse gases, is overwhelming. Pressurized metered-dose inhalers used chlorofluorocarbons propellants. Chlorofluorocarbons propellants were banned because of their big impact on the ozone layer depletion. The Montreal Protocol, introduced to protect the ozone layer, saw a planned phase-out of chlorofluorocarbons, replacing them with the hydrofluorocarbons now used in metered-dose inhalers used. While hydrofluorocarbons are not ozone depleting, they are potent greenhouse gases and have global warming potential many times that of carbon dioxide. The healthcare sector is a significant contributor to greenhouse gases emissions globally. Increases in global temperature are already having a significant impact on our climate. Combating climate change has been described as 'the greatest public health opportunity of the 21st century. To reduce the climate change impact of inhalers, several options are available including inhaler recycling, the use of alternatives devices, reduce the propellant quantity per dose or use a different propellant with a lower global warming potential. Healthcare professionals have a duty to protect and promote the health of patients and take actions to minimize the worst effects of climate change. Every effort must be made to minimize greenhouse gases release if we are to protect current and future generations

Comparação entre tecnologias de aproveitamento energético de resíduos sólidos urbanos e balanço de emissões de gases de efeito estufa no município do Rio de Janeiro, RJ, Brasil / Comparison between energy recovery technologies for municipal solid waste and greenhouse gas emissions balance in the city of Rio de Janeiro, RJ, Brazil

RESUMO O presente estudo analisou o potencial de recuperação energética dos resíduos sólidos urbanos (RSU) e o balanço de emissões de gases de efeito estufa (GEE) resultante no município do Rio de Janeiro, Rio de Janeiro, com base em três cenários tecnológicos alternativos. Os potenciais de geração foram calculados para a recuperação de gás de lixo (GDL) em 363,98 GWhe.ano-1 e 0,181 MWhe.t-1, para a biodigestão anaeróbica em 367,27 GWhe.ano-1 e 0,247 MWhe.t-1; e para a incineração em 1.139,33 GWhe.ano-1 e 0,459 MWhe.t-1. Os indicadores de intensidade de carbono mostram que, ao se considerar somente as emissões de GEE de combustão, a recuperação de GDL e a biodigestão anaeróbica apresentam os menores valores (7,488.10-4 tCO2eq.MWhe-1), enquanto a incineração apresenta o valor de 1,248 tCO2eq.MWhe-1. Por outro lado, ao se considerar também as emissões de aterro associadas, os indicadores dos dois primeiros cenários correspondem a 8,191 e 3,552 tCO2eq.MWhe-1, respectivamente.

ABSTRACT The present study analyzes the energy recovery potential of municipal solid waste (MSW) and the resulting greenhouse gas (GHG) emission balance in the city of Rio de Janeiro, Rio de Janeiro, Brazil, based on three alternative technological scenarios. The generation potentials were calculated for waste gas recovery (WGR) to be 363.98 GWhe.year-1 and 0.181 MWhe.t-1, 367.27 GWhe.year-1 and 0.247 MWhe.t-1 for anaerobic biodigestion, and 1.139.33 GWhe.year-1 and 0.459 MWhe.t-1 for incineration. Carbon intensity indicators show that, when only considering GHG emissions from the combustion process, WGR recovery and anaerobic biodigestion present the lowest values, of 7.488.10-4 tCO2eq.MWhe-1, while the value for incineration corresponds to 1.248 tCO2eq.MWhe-1. On the other hand, when considering associated landfill GHG emissions, the indicators in the first two scenarios correspond to 8.191 and 3.552 tCO2eq.MWhe-1, respectively.

Adaptation Approaches for Direct Seeded Rice to Reduce Greenhouse Gas Emission in the Perspective of Climate Change

A field experiment was conducted at research farm, Bihar Agricultural University, Sabour, India during 2017 and 2018 to gain insight crop phonology mediated greenhouse gas emission under different tillage and nitrogen management practices in direct seeded rice (DSR). The experiment was conducted in split plot design with two tillage viz. zero tillage (ZT) and conventional tillage (CT) as main plot and four nitrogen management practices viz. 100% nitrogen through neem coated urea (S1), SPAD based nitrogen management (S2), 75% through neem coated urea + 25% nitrogen through vermicompost, (S3) and ¼ nitrogen as basal and rest in equal three splits at 20, 40, 60 DAS (S4) as sub plot, in three replication. The highest yield (4.69 t ha-1), net return (Rs 46440 ha-1) and B:C ratio (1.44) were recorded from zero tilled DSR. Further, highest yield (4.82 t ha-1), net return (Rs 44880 ha-1) and B:C ratio (1.36) was obtained under split application of nitrogenous fertilizers among other subplot treatments. The range of methane (0.57- 1.47 mg m-2 hr-1) carbon dioxide (0.32- 0.61 mg m-2 hr-1) and nitrous oxide (19.58- 38.79 µg m-2 hr-1) emission was recorded lowest in zero tilled plots and split application of nitrogenous fertilizer also emitted lowest values of 1.59 mg m-2 hr-1 methane, 0.86 mg m-2 hr-1 carbon dioxide and 46.76 µg m-2 hr-1 nitrous oxide at maximum tillering stage of crop growth. Moreover, methane and nitrous oxide emission was gradually decreased from maximum tillering to harvesting stage. Zero tilled DSR with split nitrogen fertilizer application ascribed lowest greenhouse gas intensity among the other crop establishment and nitrogen management options. Thus, zero tilled method of crop establishment with split application of nitrogenous fertilizer could be a remunerative and environmentally stable method for direct seeded rice cultivation.

Efecto de bloques con propionato de calcio sobre respuestas productivas en corderos y GEI in vitro / Effect of blocks with calcium propionate on lamb productive performance and in vitro GHG

RESUMEN Objetivo. Evaluar bloques multinutricionales con y sin propionato de calcio (Pr-Ca) en la digestibilidad y cambios de peso de corderos y en la emisión de gases in vitro. Materiales y métodos. Se utilizaron doce borregos (20.17 ± 2.35 Katahdin x criollo) en tres tratamientos: Dieta basal (DB 70% paja de avena; 30% concentrado), DB+ Bloque sin Pr-Ca y DB + Bloque con 1.5% de Pr-Ca, por 50 días. Se midió producción de gas (PG) in vitro y parâmetros de cinética (Vmax, S, Lag). Se estimó la digestibilidad, CH4 y CO2 in vitro e in vivo. Resultados. El consumo de materia seca fue menor (p<0.0001) en borregos sin bloque (753 g/d) en comparación con bloque sin (839 g) o con Pr-Ca (828 g) al incluir bloques aumentó metano (16.16 y 16.18 g/d; 0 y 1.5% Pr-Ca respectivamente) que con DB (13.93 g/d). La PG in vitro fue mayor (p=0.0001) con la DB (380.76 ml) sin diferencias entre bloques (335.76 y 341.13 ml, 0 y 1.5% Pr-Ca respectivamente), y la DB tuvo mayor (p=0.0001) producción de CH4 (47.16 mol) y CO2 (200.04 mol) que con bloques (42.25 y 41.58 mol CH4; 179.21 y 176.39 moles CO2; 0 y 1.5% Ca-Pr respectivamente). Conclusiones. La suplementación con bloques mejora el consumo de materia seca. Los bloques disminuyeron la producción de gas in vitro e incrementaron la digestibilidad reduciendo CH4 y CO2.

ABSTRACT Objective. Evaluate multinutritional blocks with and without calcium propionate (Ca-Pr) on digestibility and live weight changes of lambs and in the green house emission in vitro. Materials and methods. Twelve lambs were used (20.17±2.35 Katahdin x criollo) in three treatments: Basal diet (BD 70% oat straw, 30% concentrate), BD+ Block without Ca-Pr and BD+ Block with 1.5% Ca-Pr in 50 days assay. In vitro gas production (GP) and kinetic parameters were estimated (Vmax, S, Lag). In vitro and in vivo, CH4, CO2 and digestibility were estimated. Results. The dry matter intake was the lowest (p<0.0001) in lambs without block (753 g/d) compared lambs supplemented with block without (839 g) or with Ca-Pr (828 g); including blocks increased methane (16.16 and 16.18 g/d; 0 and 1.5% Ca-Pr respectively) than BD (13.93 g/d). The GP in vitro was higher (p=0.0001) with BD (380.76, ml) than with blocks without differences among blocks (335.76 and 341.13 ml, 0 and 1.5% Ca-Pr respectively), and the BD had higher (p=0.0001) production of CH4 (47.16 mol) and CO2 (200.04 mol) than with blocks (42.25 and 41.58 mol CH4; 179.21 and 176.39 mol CO2; 0 and 1.5% Ca-Pr respectively). Conclusions. Block supplementation improved dry matter intake. Blocks reduced in vitro gas production and increased digestibility by reducing CH4 and CO2.

Inventário de Emissões de Gases de Efeito Estufa no Campus Gávea da PUC-Rio / Greenhouse Gas Emissions Inventory on Gávea Campus of PUC-Rio

RESUMO O presente trabalho apresenta resultados preliminares de um inventário de emissões de gases de efeito estufa (GEE) elaborado para o campus da PUC-Rio, situado no bairro da Gávea, zona sul da cidade do Rio de Janeiro. Foram identificadas emissões de GEE nos escopos 1 (combustão estacionária e móvel, emissões fugitivas), escopo 2 (consumo de energia elétrica) e escopo 3 (transporte, viagens, geração e descarte de resíduos sólidos), seguindo metodologias recomendadas pelo Programa Brasileiro GHG Protocol. Dentre as fontes de emissão, a mais difícil de quantificar foi justamente a principal geradora, relacionada com os deslocamentos entre o campus e as residências dos 20 mil potenciais frequentadores diários da PUC-Rio durante 2011.

ABSTRACT This paper presents the preliminary results of a greenhouse gas (GHG) inventory prepared for the campus of PUC-Rio, located in the district of Gávea, south zone of the city of Rio de Janeiro. GHG emissions have been identified in scope 1 (stationary and mobile combustion, fugitive emissions), scope 2 (electricity consumption) and scope 3 (transport, travel, generation and disposal of solid waste), according to the methodologies recommended by the Brazilian GHG Protocol Program. Among the sources of emissions, the main generator was the most difficult to quantify, and it was related to the commuting between the campus and the residences of estimated 20,000 people who frequented PUC-Rio daily in 2011.

Estimativa de geração de energia e emissão evitada de gás de efeito estufa na recuperação de biogás produzido em estação de tratamento de esgotos / Estimate of energy generation and of greenhouse gas emission on biogas recovery from wastewater treatment plant

RESUMO: O aproveitamento do biogás proveniente do tratamento de esgoto doméstico, de dejetos animais e da disposição de resíduos sólidos é uma alternativa de geração de energia elétrica com grande potencial de expansão no Brasil. O objetivo deste trabalho foi quantificar a energia fornecida pelo biogás gerado em uma estação de tratamento de esgotos (ETE) e estimar a emissão evitada de gases de efeito estufa (GEEs) com a recuperação do biogás. A ETE analisada possui vazão 33.220,8 m3.d-1 e DQO afluente 14.617,1 kg.d-1 e atende a cerca de 190.000 habitantes. Foram utilizados dados de monitoramento de agosto de 2012 a março de 2013 para quantificar os seguintes parâmetros: demanda química de oxigênio (DQO) convertida em biomassa; sulfato convertido em sulfeto; DQO convertida em metano; perdas de metano (fase líquida e gasosa); potencial energético disponível; potência elétrica disponível; emissão evitada de metano. Os seguintes resultados foram obtidos: eficiência média de tratamento de 65,6%; produção de metano de 1.427,2 m3.d-1; energia elétrica média disponível de 65.280,3 kWh.mês-1 (59% da demanda média mensal de energia da estação); emissão real evitada de metano de 946,2 kgCH4.d-1 e 17.192,6 kgCO2 eq.d-1 (potencial de aquecimento global - PAG - do CH4=21). Pode-se concluir que a recuperação do biogás na ETE Santa Quitéria resultaria em benefícios econômicos e ambientais.

ABSTRACT: The use of biogas from treatment of domestic sewage, animal waste and solid waste disposal is an alternative to generate electricity with great potential for expansion in Brazil. The aim of this paper is quantifying the energy from the biogas produced in a wastewater treatment plant (WWTP) and estimating the greenhouse gas emission avoided with the biogas recovery. The WWTP evaluated has flow 33,220.8 m3.d-1 and COD 14,617.1 kg.d-1 and serves about 190,000 inhabitants. It was used monitoring data from August/2012 to March/2013 to quantify the following parameters: COD converted into biomass; sulfate converted to sulfide; COD converted to methane; methane loss (liquid and gas); potential energy available; electrical power available; avoided emissions of methane. The following results were obtained: average treatment efficiency of 65.6%; methane production of 1,427.2 m3.d-1; average electricity available of 65,280.3 kWh.month-1 (59% of the average monthly energy demand of the WWTP); avoided emissions of 941.9 kgCH4.d-1 and 17,189.7 kgCO2 eq.d-1. Therefore, it can be concluded that the biogas recovery of in Santa Quitéria WWTP can result in economic and environmental benefits.

Enteric methane mitigation strategies in ruminants: a review / Estrategias de mitigación de metano entérico en rumiantes: revisión de literatura / Estratégias de mitigação de metano entérico em ruminantes: revisão de literatura

Livestock farming in Latin America has been criticized because of its large greenhouse gas (GHG) production resulting from the use of degraded forage and low-efficiency production performance. Agriculture contributes a significant amount of the three main greenhouse gases: methane (CH4), carbon dioxide (CO2), and nitrous oxide (N2O). Methane has a global warming potential 25 times greater than CO2. Enteric methane is an important greenhouse gas responsible for approximately 15% of global warming. The trend and legal obligation of mitigating greenhouse gas emissions will likely directly influence improved efficiency of livestock systems, including animal nutrition and handling. The development of mitigation strategies and the viability of their practical applications have been researched around the world. Various nutritional strategies to mitigate enteric methane have been studied and developed. All of them differ in terms of viability, cost, and acceptance by the producers. Their adoption should be based on the capacity to reduce methane emissions in association with economic viability and animal performance. Animal performance improvement will be achieved in production systems (mainly those related to efficient forage use) associated with good management of nutrition, health and reproduction. These are important strategies to consolidate Brazil as a food producer to the world, respecting the demands regarding land, water, biodiversity conservation and emission of greenhouse gases.

La industria pecuaria latinoamericana ha sido criticada por la emisión significativa de gases con efecto invernadero (GHG). Dicha crítica se fundamenta en los bajos indicadores zootécnicos observados en los sistemas de producción animal basados en pasturas degradadas o que se encuentran por debajo de su potencial de producción. La industria agropecuaria contribuye de manera significativa con la emisión de los tres principales GHG: metano (CH4), dióxido de carbono (CO2) y óxido nitroso (NO2). El gas metano tiene un potencial de calentamiento global 25 veces mayor que el de CO2. El metano entérico es un importante gas de efecto invernadero, que es responsable de aproximadamente el 15% del calentamiento global. La tendencia o la obligación legal de mitigar las emisiones de GHG tendrá una influencia directa sobre la necesidad del aumento de la eficiencia zootécnica en los sistemas pecuarios relacionado con el manejo nutricional de los animales que deberá ser adoptado. El desarrollo de estrategias de mitigación y la viabilidad de su aplicación práctica representan áreas de investigación alrededor del mundo. Existen diversas estrategias nutricionales que se han estudiado y desarrollado con el fin de mitigar el metano entérico. Dichas estrategias presentan diferentes viabilidades, costos y posibilidades para que sean aceptadas por los productores. La elección de la estrategia de mitigación a ser adoptada deberá estar centrada en la capacidad de reducción de las emisiones de metano asociada con la viabilidad económica y el mantenimiento del desempeño animal. El aumento de los indicadores zootécnicos que se obtendrán en los sistemas de producción (principalmente aquellos que utilicen de manera eficiente el forraje) asociado a una buena nutrición, salud y manejo reproductivo, son estrategias importantes para la consolidación de Brasil como un importante productor de alimentos para el mundo, teniendo en cuenta las demandas relacionadas con el uso del suelo, del agua, la conservación de la biodiversidad y de la emisión de gases con efecto invernadero.

A pecuária da América Latina tem sido criticada por emitir quantidades significativas de gases de efeito estufa (GHG). Tal crítica tem sido fundamentada nos baixos índices zootécnicos verificados em sistemas de exploração animal baseados em pastagens degradadas ou que se encontram abaixo do seu potencial de produção. A agropecuária contribui de forma significativa com a emissão dos três principais GHG: metano (CH4), dióxido de carbono (CO2) e óxido nitroso (NO2). O gás metano apresenta potencial de aquecimento global 25 vezes maior que o CO2. O metano entérico é um importante gás de efeito estufa, que é responsável por aproximadamente 15% do aquecimento global. A tendência ou obrigação legal de mitigar as emissões de GHG influenciará diretamente a necessidade de aumento da eficiência zootécnica nos sistemas pecuários, atrelado ao manejo nutricional dos animais a ser adotado. O desenvolvimento de estratégias de mitigação e a viabilidade da aplicação prática dessas estratégias são áreas atuais de pesquisa em todo o mundo. Existem várias estratégias de nutrição para mitigar metano entérico que têm sido estudados e desenvolvidos. Todos estes têm diferentes viabilidades, custos e possibilidades de serem adotadas pelos produtores. A escolha de qual vai ser utilizado deve basear-se na capacidade de reduzir as emissões de metano associadas com viabilidade econômica e a manutenção do desempenho do animal. O aumento nos índices zootécnicos que serão obtidos em sistemas de produção (principalmente os relacionados ao uso de forragem eficiente) associada a uma boa nutrição, saúde e manejo reprodutivo são estratégias importantes para consolidar o Brasil como um importante produtor de alimentos para o mundo, respeitando as demandas relacionadas ao uso da terra, da água, da conservação da biodiversidade e da emissão de gases de efeito estufa.

Diffusive emission of methane and carbon dioxide from two hydropower reservoirs in Brazil / Emissões difusivas de metano e de dióxido de carbono oriundas de dois reservatórios hidrelétricos

The role of greenhouse gas emissions from freshwater reservoirs and their contribution to increase greenhouse gas concentrations in the atmosphere is currently under discussion in many parts of the world. We studied CO2 and CH4 diffusive fluxes from two large neotropical hydropower reservoirs with different climate conditions. We used floating closed-chambers to estimate diffusive fluxes of these gaseous species. Sampling campaigns showed that the reservoirs studied were sources of greenhouse gases to the atmosphere. In the Serra da Mesa Reservoir, the CH4 emissions ranged from 0.530 to 396.96 mg.m–2.d–1 and CO2 emissions ranged from –1,738.33 to 11,166.61 mg.m–2.d–1 and in Três Marias Reservoir the CH4 fluxes ranged 0.720 to 2,578.03 mg.m–2.d–1 and CO2 emission ranged from -3,037.80 to 11,516.64 to mg.m–2.d–1. There were no statistically significant differences of CH4 fluxes between the reservoirs, but CO2 fluxes from the two reservoirs studied were significantly different. The CO2 emissions measured over the periods studied in Serra da Mesa showed some seasonality with distinctions between the wet and dry transition season. In Três Marias Reservoir the CO2 fluxes showed no seasonal variability. In both reservoirs, CH4 emissions showed a tendency to increase during the study periods but this was not statistically significant. These results contributed to increase knowledge about the magnitude of CO2 and CH4 emission in hydroelectric reservoirs, however due to natural variability of the data future sampling campaigns will be needed to better elucidate the seasonal influences on the fluxes of greenhouse gases.

Atualmente, em diversas partes do mundo, tem-se discutido muito sobre a contribuição das emissões de gases de efeito estufa oriundas de reservatórios hidrelétricos. Neste trabalho foram medidos fluxos difusivos de CO2 e CH4 em dois grandes reservatórios hidrelétricos neotropicais com diferentes condições climáticas (UHE Serra da Mesa e UHE Três Marias). Utilizamos câmaras flutuantes para estimar os fluxos difusivos de CO2 e CH4. As campanhas de amostragem mostraram que os dois reservatórios estudados apresentaram-se como fontes emissoras de gases por mecanismo de difusão. No reservatório de Serra da Mesa as emissões de CH4 variaram entre 0,530 e 396,96 mg.m–2.d–1 e as emissões de CO2 variaram entre –1.738,33 a 11.166,61 mg.m–2.d–1. No reservatório de Três Marias os fluxos de CH4 variaram entre 0,720 e 2.578,03 mg.m–2.d–1. Já os fluxos de CO2 variaram de -3.037,80 à 11.516,64 mg.m–2.d–1. Não houve diferença estatisticamente significativa dos fluxos de CH4 entre os reservatórios estudados, entretanto os fluxos de CO2 foram significativamente diferentes. As emissões de CO2 medidas ao longo dos períodos estudados em Serra da Mesa mostrou certa sazonalidade, com distinções entre o período de transição seco e úmido. No reservatório de Três Marias os fluxos de CO2 não apresentaram variabilidade sazonal. Em ambos os reservatórios, as emissões de CH4 apresentaram aumento do fluxo ao longo dos períodos de estudo, mas isso não foi estatisticamente significativo. Estes resultados contribuíram para aumentar o conhecimento sobre a variabilidade das emissões difusivas de CO2 e CH4 em reservatórios de usinas hidrelétricas. Entretanto, novas campanhas de amostragem serão necessárias para melhor estudar as influências sazonais sobre os fluxos dos gases de efeito estufa.

Respirometria e emissão de metano por ovinos alimentados com capim-elefante cortado com diferentes idades / Respirometry and methane emissions by sheep fed elephantgrass at different cutting ages

Objetivou-se com este trabalho mensurar a respirometria e a emissão de metano entérico por ovinos alimentados com o capim-elefante cortado aos 56, 84 e 112 dias de crescimento. Foram utilizados 18 carneiros adultos sem raça definida, com peso médio de 34,7 ± 6 kg alojados em gaiolas de estudo de metabolismo. A mensuração dos gases foi realizada através de uma câmara respirométrica de fluxo aberto. O delineamento experimental utilizado foi inteiramente casualizado, com seis repetições, e as médias foram comparadas pelo teste SNK (P<0,05). Os animais alimentados com o capim colhido após 56 dias de rebrotação consumiram mais oxigênio e produziram mais dióxido de carbono e metano. As produções de calor variaram 87,19 a 143,57 Kcal/kg 0,75/dia. O coeficiente respiratório foi semelhante entre os tratamentos, com valor médio de 0,98. A produção de metano variou entre 11,74 e 22,51 g/dia, havendo redução com o aumento da idade da planta forrageira. Quando expressa em g/kg0,75/dia, a produção deste gás foi superior para animais que receberam o capim-elefante-verde cortado aos 56 dias de idade (1,53 g/kg 0,75/dia). A emissão de metano (g) por quilo de matéria seca (MS) e de fibra insolúvel em detergente neutro (FDN) consumido para o capim colhido mais novo (56 dias) foi superior à do capim colhido no estádio mais avanço de maturação (112 dias). Porém, as emissões de metano em gramas por quilo de MS digestível (27,2 g/kg) e FDN digestível (44,4 g/kg) foram semelhantes para os capins colhidos nas diferentes idades de corte. A emissão diária de metano (g/kg 0,75/dia) foi maior em animais alimentados com a planta forrageira colhida mais nova, enquanto que se expressa em gramas por quilo de MS ou FDN digestível a emissão deste gás não sofreu influência do capim-elefante no momento do corte.

The aim of this work was to determinate the respirometry and enteric methane emission from sheep fed fresh elephant grass cut at 56, 84 and 112 days of regrowth. Eighteen crossbred sheep (34.7 ± 6 kg) individually housed in metabolic crates were used in this experiment. The gases measurements were accomplished with an open circuit respirometric chamber. The experimental design was completely randomized with three treatments (grass regowth age) and six repetitions (sheep). The data were subjected to ANOVA and means were compared by SNK test (P<0.05). The animals fed with elephant grass harvested at 56 days of regrowth had higher oxygen uptake and carbon dioxide and methane emissions. Heat production ranged from 87.19 to 143.57 Kcal/kg 0.75/day. The respiratory quotients were similar (P>0.05) among treatments, averaging 0.98. Methane emissions ranged from 11.74 to 22.51 g/day. When expressed in g/kg 0.75/day, methane emissions were higher for sheep fed fresh elephant grass with 56 days of regrowth (1.53 g/kg 0.75/day). Methane emissions expressed in g/kg of dry matter (DM) intake or neutral detergent fiber (NDF) intake were higher (P<0.05) for the grass harvested with 56 days of regrowth compared to the grass harvested in more advanced stage of maturity (112 days). However, methane emissions in g/kg of digestible DM (27.2 g/kg) and digestible NDF (44.4 g/kg) were similar among treatments. While daily methane emissions (g/kg 0.75/day) were higher in sheep fed fresh elephant grass harvested with 56 days of regrowth, it was not affected by regrowth age when expressed as g/kg of digestible DM or digestible NDF.

Technical Evaluation of Selexol-Based CO2 Capture Process for a Cement Plant.

Cement industry accounts for the second largest emitter of anthropogenic greenhouse gas in the globe with 900 kg CO2 emitted into the atmosphere from producing one tonne of cement. Hence, the effort made to mitigate this issue seems not productive , which gives rise to the design of the carbon capture and sequestration [CCS] process which is one of the few ways obtained to greatly reduce CO2 production from the cement plant. The research work assessed the technology used for the cement plant by employing an old cement plant with post-combustion CO2 capture using physical solvent (Selexol). The Aspen Hysys simulation results show that the process can capture 97% of the CO2 and lean loading of 0.37. The Ashaka Cement Plant operates at maximum capacity of approx. 1 million tonnes cement /year with CO2 released at about 500,000 tonnes per year. The capture unit was able to reduce the CO2 released into the atmosphere from 4.86% to 0.13%. The overall result of the analysis shows that selexol has proven to be thermally and chemically stable under the operating conditions used. It is recommended that, the simulation results should be retrofitted into the Ashaka cement plant, in order to determine the best CO2 capture efficiency, performance which results to the choice of this capture technology.

Greenhouse Gas Emission Determinants in Nigeria: Implications for Trade, Climate Change Mitigation and Adaptation Policies.

This study investigated and analyzed the determinants of Carbon Dioxide (CO2) emission in Nigeria. The study relied on secondary data from World Bank and Central Bank of Nigeria covering 40 years (1970-2009). The data were analyzed using Zellner’s Seemingly Unrelated Regression (SURE) model. The results of the analysis show that fossil energy demand or consumption, rents from forestry trade, agricultural land area expansion and farm technology were significant determinants of greenhouse gas (GHG) emission in the study area. On the other hand, the second equation indicated that fossil fuel energy demand was exogenously determined by economic growth rate (proxied by GDP growth rate) and farm technology applied in the country. It was recommended that Nigeria should put in place policies that will tax companies or firms emitting GHGs and utilize such tax proceeds for research and building the capacities of farmers to adapt to deleterious effect of climate change in the country and continent. The development of existing and new technologies for adapting to climate change and variability, building of environmental consciousness of Nigerians through curriculum restructuring and provision of weather information services by the Nigerian governments and their agencies to enable farmers plan against weather uncertainty and risks were also recommended.

A Preliminary Estimation on Carbon Footprint of Raw Water from the Reservoirs for Domestic Use in Taiwan.

This study aims to evaluate the carbon footprint of raw water from reservoirs for domestic use in Taiwan. It also provides a preliminary measure and reference database for greenhouse gas (GHG) emission of reservoir systems in Taiwan. Four reservoirs, Feitsui (F.T.) and Liyutan (L.Y.T.) in subtropical zone and Nanhua (N.H.) and Tsengwen (T.W.) in tropical zone, were selected as the cases to be examined for carbon footprint inventory, including the GHG emission from the water body and from human activities. Carbon footprint inventory followed PAS 2050 (2011 Specification for the assessment of the life cycle greenhouse gas emissions of goods and services). GHG emission from water body followed the instruction of UNESCO guidelines. The boundary of this inventory covers the water intake works, impoundment region, the dam, the affiliated hydroelectricity power plant, the administration center and other facilities. In this study, the floating chambers with gas chromatography (GC) were chosen to measure the GHG flux from the water body. For the emission of CH4 and N2O from the water body, there are no significantly difference between the fluxes during the daytime and nighttime. For carbon dioxide, the instantaneous flux during the nighttime is higher than the daytime flux. The two reservoirs in tropical zone emit more CO2e from the water body than those in subtropical zone. Summarizing the direct and indirect GHG emission, for the four reservoirs, the annual emission quantities ranged from 653 ton of CO2e to 23,146 ton of CO2e. The carbon footprint of water supply for domestic use ranged from 0.002 kg CO2e/m3 to 0.028 kg CO2e/m3. Roughly speaking, the total GHG emission quantity of the 24 main reservoirs in Taiwan was estimated to be around 121,800 ton of CO2e with the total yield of 4.35 billion m3 of water annually using the highest carbon footprint 0.028 kg CO2e/m3.

A review on soil carbon accumulation due to the management change of major Brazilian agricultural activities

Agricultural areas deal with enormous CO2 intake fluxes offering an opportunity for greenhouse effect mitigation. In this work we studied the potential of soil carbon sequestration due to the management conversion in major agricultural activities in Brazil. Data from several studies indicate that in soybean/maize, and related rotation systems, a significant soil carbon sequestration was observed over the year of conversion from conventional to no-till practices, with a mean rate of 0.41 Mg C ha-1 year-1. The same effect was observed in sugarcane fields, but with a much higher accumulation of carbon in soil stocks, when sugarcane fields are converted from burned to mechanised based harvest, where large amounts of sugarcane residues remain on the soil surface (1.8 Mg C ha-1 year-1). The higher sequestration potential of sugarcane crops, when compared to the others, has a direct relation to the primary production of this crop. Nevertheless, much of this mitigation potential of soil carbon accumulation in sugarcane fields is lost once areas are reformed, or intensive tillage is applied. Pasture lands have shown soil carbon depletion once natural areas are converted to livestock use, while integration of those areas with agriculture use has shown an improvement in soil carbon stocks. Those works have shown that the main crop systems of Brazil have a huge mitigation potential, especially in soil carbon form, being an opportunity for future mitigation strategies.

Áreas agrícolas trocam enormes fluxos de CO2, oferecendo uma oportunidade para mitigar o efeito estufa. Neste trabalho, estudou-se o potencial de sequestro de carbono em razão da conversão no manejo das principais atividades agrícolas do Brasil. Dados de vários estudos têm indicado que no sistema soja/milho e nas respectivas rotações, ocorre um sequestro de carbono no solo significativo ao longo dos anos de conversão do plantio convencional para o plantio direto, com uma média de 0,41 Mg C ha-1 ano-1. O mesmo efeito tem sido observado nos canaviais, porém há maiores acúmulos de carbono no solo quando as áreas de cana-de-açúcar são convertidas da colheita baseada na queima para a mecanizada, em que grandes quantidades de palha são deixadas na superfície do solo (1,8 Mg C ha-1 ano-1). Esse maior potencial de acúmulo de carbono no solo nos canaviais, comparado com outras culturas, está diretamente relacionado com a maior produção primária dessa cultura. Apesar disso, muito desse potencial de sequestro é perdido, uma vez que os canaviais são reformados, sob preparo intensivo do solo. As áreas de pasto mostram uma depleção nos estoques de carbono, quando convertidas de áreas naturais; porém, a integração dessas áreas com agricultura pode promover o aumento nos estoques de carbono do solo. Os trabalhos têm mostrado que as principais atividades agrícolas do Brasil possuem um grande potencial de mitigação, especialmente na forma de acúmulo de carbono no solo, sendo uma oportunidade para estratégias futuras.

A review on soil carbon accumulation due to the management change of major Brazilian agricultural activities / Uma revisão sobre o acúmulo de carbono no solo devido a mudança de manejo nas principais atividades agrícolas do Brasil

Agricultural areas deal with enormous CO2 intake fluxes offering an opportunity for greenhouse effect mitigation. In this work we studied the potential of soil carbon sequestration due to the management conversion in major agricultural activities in Brazil. Data from several studies indicate that in soybean/maize, and related rotation systems, a significant soil carbon sequestration was observed over the year of conversion from conventional to no-till practices, with a mean rate of 0.41 Mg C ha-1 year-1. The same effect was observed in sugarcane fields, but with a much higher accumulation of carbon in soil stocks, when sugarcane fields are converted from burned to mechanised based harvest, where large amounts of sugarcane residues remain on the soil surface (1.8 Mg C ha-1 year-1). The higher sequestration potential of sugarcane crops, when compared to the others, has a direct relation to the primary production of this crop. Nevertheless, much of this mitigation potential of soil carbon accumulation in sugarcane fields is lost once areas are reformed, or intensive tillage is applied. Pasture lands have shown soil carbon depletion once natural areas are converted to livestock use, while integration of those areas with agriculture use has shown an improvement in soil carbon stocks. Those works have shown that the main crop systems of Brazil have a huge mitigation potential, especially in soil carbon form, being an opportunity for future mitigation strategies.

Áreas agrícolas trocam enormes fluxos de CO2, oferecendo uma oportunidade para mitigar o efeito estufa. Neste trabalho, estudou-se o potencial de sequestro de carbono em razão da conversão no manejo das principais atividades agrícolas do Brasil. Dados de vários estudos têm indicado que no sistema soja/milho e nas respectivas rotações, ocorre um sequestro de carbono no solo significativo ao longo dos anos de conversão do plantio convencional para o plantio direto, com uma média de 0,41 Mg C ha-1 ano-1. O mesmo efeito tem sido observado nos canaviais, porém há maiores acúmulos de carbono no solo quando as áreas de cana-de-açúcar são convertidas da colheita baseada na queima para a mecanizada, em que grandes quantidades de palha são deixadas na superfície do solo (1,8 Mg C ha-1 ano-1). Esse maior potencial de acúmulo de carbono no solo nos canaviais, comparado com outras culturas, está diretamente relacionado com a maior produção primária dessa cultura. Apesar disso, muito desse potencial de sequestro é perdido, uma vez que os canaviais são reformados, sob preparo intensivo do solo. As áreas de pasto mostram uma depleção nos estoques de carbono, quando convertidas de áreas naturais; porém, a integração dessas áreas com agricultura pode promover o aumento nos estoques de carbono do solo. Os trabalhos têm mostrado que as principais atividades agrícolas do Brasil possuem um grande potencial de mitigação, especialmente na forma de acúmulo de carbono no solo, sendo uma oportunidade para estratégias futuras.

The Protein Puzzle: The Consumption and Production of Meat, Dairy and Fish in the European Union.

Meat, dairy, eggs and fish are important components of the European diet These animal products are not only important in terms of taste and tradition; they also provide essential nutrients such as proteins, iron, calcium and vitamins. Fish also provides essential fatty acids and vitamin D. Furthermore, livestock production and fisheries are important economic sectors for Europe’s rural areas. However, livestock production and fisheries have large environmental effects, both within and outside Europe From a global perspective, impacts on terrestrial and marine biodiversity and emissions of greenhouse gases (GHG) and various forms of reactive nitrogen are most dominant. The large areas of land needed for grassland and feed production are an important cause of biodiversity loss. In the EU, about two thirds of the total agricultural area is used for livestock production. Around 75% of the protein-rich feed is imported, mainly from Brazil and Argentina where large areas of land are needed for its production. Conversion of plant energy and proteins into edible animal products is a generally inefficient use of resource These resources include land, water, fertilisers and fossil energy, among other things. This can be illustrated by the fact that, for each EU citizen, every day almost 3 kilograms of feed is consumed by EU livestock, 0.8 kilogram of which in cereals and 0.8 kilogram in grass (dry matter). This feed is converted into 0.1 kilograms of meat and 0.8 kilograms of milk, being the average EU consumption. Livestock production is a source of greenhouse gas emissions and certain forms of reactive nitrogen Around 10% of EU greenhouse gas emissions are caused by livestock production. Together, the beef and dairy sectors are responsible for two thirds of these emissions. A large quantity of nitrogen fertiliser is needed, each year, to sustain Europe’s high production levels of grass, cereals and other crops. More than 80% of this nitrogen input is lost, leading to various environmental problems, including the loss of terrestrial biodiversity and algae blooms in coastal waters. There are large differences in greenhouse gas and nitrogen emissions between the various animal products and production practices. Animal husbandry is associated with several ethical issues These issues, among other things, are related to limited space, floor type and concentrated feeds, and to the breeds being used. Farm animals, especially when kept in conventional types of housing, experience various forms of discomfort. Animal diseases diminish not only animal well-being, but some animal diseases and the widespread use of antibiotics also cause human health risks. However, improving animal welfare generally leads to higher feed requirements and higher emission levels, thus implying a trade-off between animal welfare and environmental issues. Many marine fish populations are overexploited. despite new fishing grounds, EU catches are declining rapidly Catches in the main EU fishing areas have declined by a third since the early 1990s, partly because of EU regulation to prevent overfishing. EU aquaculture is growing, but at a much slower rate than in other regions. Worldwide, 40% of fish production comes from aquaculture, compared with about 20% in Europe. The EU, therefore, relies heavily on imports to meet its demand for fish. Average EU consumption of animal protein per capita is about twice the global average Meat consumption in Europe is twice the world average; for dairy produce it is even three times higher. Average EU consumption of meat, dairy and fish has increased strongly over the last 50 years. The total per-capita protein consumption (including vegetable sources) is about 70% higher than recommended. This, in itself, probably would have no adverse effects on human health, if not for the associated intake of saturated fatty acids, which lead to increased risks of cardiovascular diseases. The average intake of saturated fatty acids is about 40% higher than recommended. Thus, a reduction in the consumption of livestock products, notably in high-fat products, would reduce the European disease burden. Global demand for animal products is expected to increase significantly, in the coming decades, as a result of a growing global population and increasing prosperity As a consequence, cropland and grassland areas are expected to expand by 10% to 20% over the coming decades, leading to significant losses of terrestrial biodiversity, especially in South Asia, Sub-Saharan Africa and South America. Moreover, greenhouse gas and nitrogen emissions related to agricultural production also are expected to increase. Globally, already around 30% of the total human-induced biodiversity loss is related to livestock production. Currently, about 80% of global commercial fish populations are being fully exploited or overexploited, leading to large impacts on marine biodiversity. Capture fisheries, therefore, are unlikely to be able to contribute to meeting the increasing fish demand. Fish farming could be an option Fish farming of predatory species, such as salmon, uses wild-caught fish as part of the fish feed. Further innovations in the composition of this feed, but also a switch to an increased consumption of herbivorous fish, would reduce the amounts of wild-caught fish required in fish feed. This would involve only a small increase in agricultural land used in the production of the feed for these additional numbers of farmed herbivorous fish. In this way, wild fish stocks would be protected, could recover and possibly provide higher catches in the future. There are many options to reduce the impacts of livestock production Main points of intervention are: shifts in consumption, reduction in food losses, changes in husbandry systems and animal breeds, feed conversion and feed composition, nutrient management, crop yields and land management. Modelling results demonstrate that significant reductions in environmental pressure are possible, at the global level, by improving crop yields and feed conversion and by a reduction in food losses along the food chain. The same results indicate that a reduction in the EU consumption of animal products would lead to a significant reduction in environmental impacts, mainly by reducing land conversion outside the EU. The fact that this would take place mainly outside the EU is partly a result of the current design of the Common Agricultural Policy (CAP), which stimulates European farmers to keep their land in agricultural production. The options for the EU to reduce the impacts of livestock production can be grouped into three broad, partially complementary strategies: shifts in consumption, resource efficiency and producing with fewer local impacts Consumption shifts, particularly a reduction in the consumption of livestock products, will not only have environmental benefits, but may also reduce the cardiovascular disease burden. This option is easy and robust, but changing consumption patterns is a slow cultural process. Improving production efficiency is already common practice, as there are many synergies between enhancing production and reducing costs. Further improvements along this route are certainly possible, especially regarding a better use of relatively cheap inputs (e.g. fertilisers) and reducing emissions. Producing with fewer local impacts may have negative environmental effects elsewhere, since production may be less efficient, such as in the case of improved animal welfare. More robust production systems with fewer local impacts, generally, lead to higher costs for farmers. However, if done properly, this would lead to lower societal costs by reducing local environmental impacts, animal suffering and public health risks. Governments and actors in the food chain both could play a role in the implementation of the three strategies Current policy and institutional setting mainly drive farmers and other actors in the direction of cost price reductions, and thus primarily support the ‘efficiency’ strategy. Policies aimed at reducing consumption hardly exist, and policies regarding producing with fewer local impacts are usually secondary to economic and trade policies. Especially the EU, but also the national governments, have a large influence on the agriculture and fisheries sectors. Main policy instruments are the Common Agricultural Policy and the Common Fisheries Policy, which are currently undergoing a reform. Food and agriculture may play a role in EU initiatives, such as ‘Resource Efficient Europe’. Individual consumers and actors in food production have many opportunities to reduce the impacts of livestock production, independently from government actions. Consumers could shift to the consumption of products with lower environmental or animal welfare impacts. Retailers could expand their assortment of these products, and could enter into agreements with farmers and other food suppliers to improve production techniques. The full report can be downloaded for free from http://www.pbl.nl/sites/default/files/cms/publicaties/Protein_Puzzle_web_1.pdf.

Global Climate Change: A Threat to Food Security and Environmental Conservation.

Rapid socio-economic changes in some developing countries like India, China, etc., are influencing dramatically the fuel consumption pattern world over. An increase of 880 TWh of electricity consumption in transport in 2030 compared with the Reference Scenario, of which 90% occurs in PLDVs, results in about 250 Mt of additional CO2 emissions. The rise in the amount of CO2 in the atmosphere is 1.0 – 3.50C (1PCC, 2007a). If emissions of greenhouse gases, and in particular CO2, continue unabated the enhanced greenhouse effect may alter the world’s climate system irreversibly. This review attempted to examine how climate change constitutes a threat to food security and environmental conservation. Climate change (CC) refers to changes in modern climate. It reflects abnormal variations to the expected climate within the earth’s atmosphere and subsequent effects on other parts of the earth. It is emphasized that CC poses a threat to food security as it impacts on natural systems and resources through erratic rainfall patterns, heightened temperature and susceptibility to pest and disease outbreaks hence decreasing crop yields and consequently increased hunger. CC negatively affects biodiversity conservation and management through exacerbated drought conditions, increased risk of wildfires leading to some extreme events like heat, waves, river and coastal flooding, landslides, storms, hurricanes and tornadoes which culminate in environmental degradation. For its effects to be reduced establishment of more forest plantations and maintenance of the existing natural and artificial forests should be encouraged. Saving biodiversity in the form of standing forests and interact lands can help prevent climate change and help communities and natural areas cope with a changing planet. At the same time, helping nature become more reification climate change through a combination of management restoration and protection strategies will help prepare places, plants, animals and people for climatic change successful adoption of living system can help ensure their ability to support the needs of people and better withstand future changes.

Climate change and human health

Climactic changes, especially global warming, are potentially the largest global threat to human health and the source of the greatest number of cases of disease. If current emissions and land use trends continue unchecked, future generations will face more serious conditions, including injury, disease, and death related to natural disasters and heat waves, higher rates of climate-related infections, widespread malnutrition, and more allergy and air pollutionrelated morbidity and mortality. This review highlights the relationship between global climate changes and human health and provides some suggestions for improvement. According to the Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC) published in 2007, global warming is caused by greenhouse gas (GHG) emissions. The most important GHG is carbon dioxide (CO2), which is released by the burning of fossil fuels and, to a lesser extent, by land use practices, followed by nitrous oxide and methane. IPCC predicts that global temperatures will rise 1.8degrees C-4.0degrees C by 2099. According to the report, we can expect a significant rise in sea levels, massive species extinctions, changes in storm and drought cycles, altered ocean circulation, and redistribution of vegetation after crossing the "tipping point" of global warming. Human health will be adversely affected by the accelerating climate change. This review stimulates health care providers to provide quality care to susceptible individuals confronting new threats from climactic changes, as well as to work toward a mitigation of the drivers of climate change at the individual, community, and policy levels as part of a long-term commitment to protecting public health.

Emissão de gases de efeito estufa no ciclo de vida do etanol: estimativa nas fases de agricultura e industrialização em Minas Gerais / Greenhouse gas emissions in the life cycle of ethanol: estimation in agriculture and industrialization stages in Minas Gerais, Brazil

O presente estudo apresenta uma estimativa da emissão de gases de efeito estufa (CO2, CH4 e N2O) nas etapas de agricultura e industrialização de cana-de-açúcar para produção de etanol em usinas localizadas no Estado de Minas Gerais. Princípios de Avaliação do Ciclo de Vida foram considerados na quantificação das emissões. Consideraram-se as emissões no consumo de combustíveis, utilização de insumos da agricultura, liberação de N2O no solo, emissões na queima da cana-de-açúcar e utilização de produtos químicos em 11 destilarias. Os resultados mostram uma emissão total de 1.539,60 kg CO2eq/ha·ano, com maior proporção para as emissões decorrentes da queima de cana-de-açúcar e consumo de combustíveis, os quais, em conjunto, representam mais de 50 por cento do total de emissões.

This research presents an estimate of greenhouse gas emissions (CO2, CH4 e N2O) in the stages of agriculture and sugarcane industrialization for the production of ethanol in mills located in the state of Minas Gerais, Brazil. Life Cycle Assessment principles were considered in the quantification of emissions. The use of fuels, agricultural inputs, N2O emissions on soil, sugarcane burning emissions and use of chemical products of 11 mills were considered in this study. The results show a total emission of 1,539.60 kg CO2eq/ha·year, considering as the main key sources: sugarcane burning and use of fuels, which account for more than 50 percent of the total emissions.