Fuel consumption by agricultural machinery: a review of pollutant emission control technologies / Consumo de combustível por máquinas agrícolas: uma revisão das tecnologias de controle de emissão de poluentes

ABSTRACT: Most energy used to operate agricultural machines in the field is generated from fossil fuel combustion. The combustion process emits atmospheric pollutants, increasing the emission of greenhouse gases (GHGs). In this context, this review is to discuss technologies for mitigating diesel engine GHG emissions to advance sustainable development in the agricultural machinery sector. This paper presents strategies and technologies widely adopted by agricultural machinery manufacturers in controlling pollutant emissions during fuel combustion. The findings of this study encompass sustainable alternative technologies, such as selective catalytic reduction, exhaust gas recirculation, diesel particulate filter, and fuels. This study helps reveal the environmental impact of agricultural field operations that generate GHG emissions.

RESUMO: Grande parte da energia utilizada para o funcionamento das máquinas agrícolas em suas operações no campo ainda é resultante da combustão de combustíveis fósseis. O processo de combustão provoca a emissão de poluentes atmosféricos que contribuem para o aumento dos Gases de Efeito Estufa (GEE). Neste contexto, esta revisão tem como objetivo descrever as tecnologias que contribuem para mitigar as emissões de GEE pelos motores de ciclo Diesel, a fim de contribuir para a compreensão e o desenvolvimento da sustentabilidade no setor de máquinas agrícolas. São apresentadas as estratégias e tecnologias que comumente estão sendo adotadas pelos fabricantes de máquinas agrícolas para o controle das emissões de poluentes, durante o processo de combustão do combustível. Os achados do estudo apresentam as alternativas tecnológicas sustentáveis como a Selective Catalytic Reduction, Exhaust Gas Recirculation, Diesel Particulate Filter, e sobre o uso de combustíveis alternativos. Ainda, contribui para o entendimento do impacto ambiental das operações agrícolas em campo, que provocam as emissões de GEE.

Fuel consumption by agricultural machinery: a review of pollutant emission control technologies / Consumo de combustível por máquinas agrícolas: uma revisão das tecnologias de controle de emissão de poluentes

Most energy used to operate agricultural machines in the field is generated from fossil fuel combustion. The combustion process emits atmospheric pollutants, increasing the emission of greenhouse gases (GHGs). In this context, this review is to discuss technologies for mitigating diesel engine GHG emissions to advance sustainable development in the agricultural machinery sector. This paper presents strategies and technologies widely adopted by agricultural machinery manufacturers in controlling pollutant emissions during fuel combustion. The findings of this study encompass sustainable alternative technologies, such as selective catalytic reduction, exhaust gas recirculation, diesel particulate filter, and fuels. This study helps reveal the environmental impact of agricultural field operations that generate GHG emissions.

Grande parte da energia utilizada para o funcionamento das máquinas agrícolas em suas operações no campo ainda é resultante da combustão de combustíveis fósseis. O processo de combustão provoca a emissão de poluentes atmosféricos que contribuem para o aumento dos Gases de Efeito Estufa (GEE). Neste contexto, esta revisão tem como objetivo descrever as tecnologias que contribuem para mitigar as emissões de GEE pelos motores de ciclo Diesel, a fim de contribuir para a compreensão e o desenvolvimento da sustentabilidade no setor de máquinas agrícolas. São apresentadas as estratégias e tecnologias que comumente estão sendo adotadas pelos fabricantes de máquinas agrícolas para o controle das emissões de poluentes, durante o processo de combustão do combustível. Os achados do estudo apresentam as alternativas tecnológicas sustentáveis como a Selective Catalytic Reduction, Exhaust Gas Recirculation, Diesel Particulate Filter, e sobre o uso de combustíveis alternativos. Ainda, contribui para o entendimento do impacto ambiental das operações agrícolas em campo, que provocam as emissões de GEE.

Patterns of production and sustainability of cattle ranching in the state of Pará - Brazilian Amazon / Padrões de produção e sustentabilidade da pecuária bovina no estado do Pará - Amazônia Brasileira

The aim of this study was to analyze the production patterns present in rural properties producing cattle in the micro-regions that make up the state of Pará. Exploratory Factor Analysis (EFA) was applied to identify the patterns, and these data are used to evaluate correlation between the heterogeneity of rural properties and the environmental impact on the identified patterns. The theoretical contribution is based on discussions on global impacts of food production and environmental sustainability and the impacts of livestock production systems in Brazil and the Amazon. Survey data were taken from the 2017 Agricultural Census, available for the 144 municipalities in the state, and pooled into 22 micro-regions. Three patterns of rural properties were identified: the first related to conservation management practices and called transition management; the second highlights aspects associated with information technology and communication (ICT) and productivity called technical productive efficiency; the third indicates the importance of social organization and access to information called social participation. With these patterns, it was possible to develop the Traditional Performance Indicator (TPI), in which the micro-regions of São Félix do Xingu, Itaituba and Conceição do Araguaia were those with the highest values of this indicator, water protection practices are present in the properties, however, in precarious conditions, and conservation practices are rarely used. The correlation between heterogeneity, measured by the size of pasture area in each microregion, and the TPI is positive, strong and significant. In this transition context, public policies are essential to provide access to infrastructure, credit and good animal health and biotechnology practices.(AU)

O objetivo deste estudo foi analisar os padrões de produção presentes nos estabelecimentos rurais produtores de gado bovino nas microrregiões que formam o estado do Pará. Foi aplicada a técnica estatística de Análise Fatorial Exploratória (AFE) para identificar os padrões, e com esses dados avaliar a correlação entre a heterogeneidade das propriedades rurais produtoras e o impacto ambiental nos padrões identificados. O aporte teórico está ancorado nas discussões sobre os impactos globais da produção de alimentos e a sustentabilidade ambiental e os impactos da pecuária no Brasil e na Amazônia. Os dados da pesquisa foram extraídos do Censo Agropecuário de 2017, disponíveis para os 144 municípios do estado, e agregados em 22 microrregiões. Foram identificados três padrões de estabelecimentos rurais: o primeiro relacionado as práticas de gestão conservacionistas e denominado de gestão em transição; o segundo destaca aspectos associados a tecnologia de informática e comunicação (TIC) e a produtividade denominado de eficiência técnica produtiva; o terceiro indica a importância da organização social e o acesso a informação denominado de participação social. Com os resultados desses padrões foi possível gerar o Indicador de Desempenho Tradicional (IDT), em que as microrregiões de São Félix do Xingu, Itaituba e Conceição do Araguaia foram aquelas com maior nível desse indicador, as práticas de proteção das águas se fazem presente nas propriedades, porém, em condições precárias, e as práticas conservacionistas são pouco empregadas. A correlação entre a heterogeneidade, medida pelo tamanho da área de pasto em cada microrregião, e o IDT é positiva, forte e significativa. Nesse contexto de transição, as políticas públicas são essenciais para proporcionar acesso a infraestrutura, crédito e boas práticas de saúde animal e biotecnologia.(AU)

CH4 and N2O fluxes from planted forests and native Cerrado ecosystems in Brazil

Forest soils are N2O sources and commonly act as CH4 sinks. This study evaluated the dynamics of the CH4 and N2O fluxes of soils under Eucalyptus plantations and native Cerrado vegetation, as well as possible interactions between environmental factors and fluxes. The study was carried out in the Distrito Federal, Brazil, during 26 months, in three areas: in two stands of the hybrid Eucalyptus urophylla × Eucalyptus grandis, planted in 2011 (E1), and in 2009 (E2) and native Cerrado vegetation (CE). Measurements to determine the fluxes in a closed static chamber were carried out from Oct 2013 to Nov 2015. Soil and climate factors were monitored. During the study period, the mean CH4 fluxes were –22.48, –8.38 and –1.31 μg CH4 m–2 h–1 and the mean N2O fluxes 5.45, 4.85 and 3.85 μg N2O m–2 h–1 from E1, E2 and CE, respectively. Seasonality affected plantations in the studied sites. Cumulative CH4 influxes were calculated (year-1: –1.86 to -0.63 kg ha–1 yr–1; year-2: –1.85 to –1.34 kg ha–1 yr–1). Cumulative N2O fluxes in the three sites were ≤ 0.85 kg ha–1 yr–1. The change in land use from Cerrado to Eucalyptus plantations did not significantly changed regarding greenhouse gases (GHG), compared to the native vegetation. Flux rates of both gases (N2O and CH4) were low. Temporal variations in GHG fluxes and different ages of the stands did not cause significant differences in cumulative annual fluxes.

CH4 and N2O fluxes from planted forests and native Cerrado ecosystems in Brazil

Forest soils are N2O sources and commonly act as CH4 sinks. This study evaluated the dynamics of the CH4 and N2O fluxes of soils under Eucalyptus plantations and native Cerrado vegetation, as well as possible interactions between environmental factors and fluxes. The study was carried out in the Distrito Federal, Brazil, during 26 months, in three areas: in two stands of the hybrid Eucalyptus urophylla × Eucalyptus grandis, planted in 2011 (E1), and in 2009 (E2) and native Cerrado vegetation (CE). Measurements to determine the fluxes in a closed static chamber were carried out from Oct 2013 to Nov 2015. Soil and climate factors were monitored. During the study period, the mean CH4 fluxes were –22.48, –8.38 and –1.31 μg CH4 m–2 h–1 and the mean N2O fluxes 5.45, 4.85 and 3.85 μg N2O m–2 h–1 from E1, E2 and CE, respectively. Seasonality affected plantations in the studied sites. Cumulative CH4 influxes were calculated (year-1: –1.86 to -0.63 kg ha–1 yr–1; year-2: –1.85 to –1.34 kg ha–1 yr–1). Cumulative N2O fluxes in the three sites were ≤ 0.85 kg ha–1 yr–1. The change in land use from Cerrado to Eucalyptus plantations did not significantly changed regarding greenhouse gases (GHG), compared to the native vegetation. Flux rates of both gases (N2O and CH4) were low. Temporal variations in GHG fluxes and different ages of the stands did not cause significant differences in cumulative annual fluxes.(AU)

The neglected contribution of mound-building termites on CH4 emissions in Brazilian pastures

Based on previous reports, our study aimed to obtain the first estimate on the contribution of termite mounds to CH4 emissions in Brazilian Cerrado pastures. We estimated that termite mounds occupy an area larger than 200,000 ha in degraded pastures, an important loss of grazing area considering the current scenario of land-use change of pastures to other crops in Brazil. Moreover, mound-building termites in degraded pastures may be responsible for CH4 emissions greater than 11 Mt CO2 eq. yr−1, which would notably affect the greenhouse gases (GHG) balance of grass-fed cattle production in Brazil. In this sense, it is urgent to conduct field-scale studies about the CH4 emissions by mound-building termites in pastures and its contribution to the C footprint of Brazilian beef.

Energy efficiency and emissions of CO2, CH4, and N2O in organic and conventional rice production / Eficiência energética e emissões de CO2, CH4 e N2O em arroz sob cultivo orgânico e convencional

Rice is the second-most produced cereal worldwide and actively contributes to greenhouse gas (GHG) emissions, particularly methane, especially under deepwater production. Assessments of energy efficiency (EE) and GHG emissions can indicate the sustainability level of agrosystems and support decisions related to the reduction of production costs and environmental pollution. This study aimed to assess both EE and GHG emissions in organic and conventional rice production in the Southern region of Brazil. For this study, eight rice fields were evaluated. Energy inputs and outputs were calculated by multiplying the production input amounts by their respective calorific values or energy coefficients at each stage of production. EE was determined using the ratio between the total energy output and the total energy consumed during the production process. GHG emissions were estimated using the principles of the lifecycle assessment methodology in addition to the Intergovernmental Panel on Climate Change (IPCC) recommendations. Each 1.0 MJ consumed during the production of organic and conventional rice produced renewable energy averages of 10.5 MJ and 7.90 MJ, respectively, as grains. The primary energy expenses for organic rice were represented by seeds, fuel, tractors, and agricultural machinery and implements, and those for conventional rice were seeds, fuel, and fertilizers. Each kilogram of organic and conventional rice produced accounted for the emission of 0.21 and 0.32 kg of CO2eq, respectively, during the production cycles and delivery to the warehouse, with seeds, fuel, and fertilizers being the main sources of CO2eq emissions to the atmosphere.

O arroz é o segundo cereal mais cultivado no mundo e contribui ativamente nas emissões de GEE, principalmente em áreas produzidas sob inundação, com destaque para a produção de gás metano. A eficiência energética (EE) e as emissões de gases de efeito estufa (GEE) podem indicar o nível de sustentabilidade dos agrossistemas e a tomada de decisões relativas à redução dos custos de produção e poluição do ambiente. O objetivo deste trabalho foi avaliar a EE e emissões de GEE nas culturas do arroz sob cultivo orgânico e convencional na região sul do Brasil. Para isso, foram avaliadas oito áreas de arroz. As entradas e saídas de energia foram calculadas pela multiplicação da quantidade de produtos utilizados para a produção de arroz pelos seus respectivos poderes caloríficos ou coeficientes energéticos em cada etapa de produção. A EE foi obtida pela razão entre a quantidade de energia total de saída e o consumo total de energia durante o processo produtivo. Para estimar a emissão de GEE, foram aplicados princípios da metodologia de avaliação do ciclo de vida e recomendações do Painel Intergovernamental sobre Mudanças Climáticas (IPCC). Para cada 1,0 MJ de energia consumida na produção orgânica de arroz sob os sistemas orgânico e convencional, se produziram respectivamente em média, 10,5 MJ e 7,90 MJ de energia renovável, na forma de grãos. Os principais gastos energéticos no arroz orgânico foram com sementes, combustível, tratores, máquinas e implementos agrícolas e para o arroz convencional foram sementes, combustível e fertilizantes. Para cada 1 kg de grãos dos sistemas orgânicos e convencional são emitidos respectivamente 0,21 e 0,32 kg de CO2eq durante seus ciclos de produção e entrega no armazém, sendo as sementes, combustíveis e fertilizantes as principais fontes de emissão de CO2eq à atmosfera.

Energy efficiency and emissions of CO2, CH4, and N2O in organic and conventional rice production / Eficiência energética e emissões de CO2, CH4 e N2O em arroz sob cultivo orgânico e convencional

Rice is the second-most produced cereal worldwide and actively contributes to greenhouse gas (GHG) emissions, particularly methane, especially under deepwater production. Assessments of energy efficiency (EE) and GHG emissions can indicate the sustainability level of agrosystems and support decisions related to the reduction of production costs and environmental pollution. This study aimed to assess both EE and GHG emissions in organic and conventional rice production in the Southern region of Brazil. For this study, eight rice fields were evaluated. Energy inputs and outputs were calculated by multiplying the production input amounts by their respective calorific values or energy coefficients at each stage of production. EE was determined using the ratio between the total energy output and the total energy consumed during the production process. GHG emissions were estimated using the principles of the lifecycle assessment methodology in addition to the Intergovernmental Panel on Climate Change (IPCC) recommendations. Each 1.0 MJ consumed during the production of organic and conventional rice produced renewable energy averages of 10.5 MJ and 7.90 MJ, respectively, as grains. The primary energy expenses for organic rice were represented by seeds, fuel, tractors, and agricultural machinery and implements, and those for conventional rice were seeds, fuel, and fertilizers. Each kilogram of organic and conventional rice produced accounted for the emission of 0.21 and 0.32 kg of CO2eq, respectively, during the production cycles and delivery to the warehouse, with seeds, fuel, and fertilizers being the main sources of CO2eq emissions to the atmosphere.(AU)

O arroz é o segundo cereal mais cultivado no mundo e contribui ativamente nas emissões de GEE, principalmente em áreas produzidas sob inundação, com destaque para a produção de gás metano. A eficiência energética (EE) e as emissões de gases de efeito estufa (GEE) podem indicar o nível de sustentabilidade dos agrossistemas e a tomada de decisões relativas à redução dos custos de produção e poluição do ambiente. O objetivo deste trabalho foi avaliar a EE e emissões de GEE nas culturas do arroz sob cultivo orgânico e convencional na região sul do Brasil. Para isso, foram avaliadas oito áreas de arroz. As entradas e saídas de energia foram calculadas pela multiplicação da quantidade de produtos utilizados para a produção de arroz pelos seus respectivos poderes caloríficos ou coeficientes energéticos em cada etapa de produção. A EE foi obtida pela razão entre a quantidade de energia total de saída e o consumo total de energia durante o processo produtivo. Para estimar a emissão de GEE, foram aplicados princípios da metodologia de avaliação do ciclo de vida e recomendações do Painel Intergovernamental sobre Mudanças Climáticas (IPCC). Para cada 1,0 MJ de energia consumida na produção orgânica de arroz sob os sistemas orgânico e convencional, se produziram respectivamente em média, 10,5 MJ e 7,90 MJ de energia renovável, na forma de grãos. Os principais gastos energéticos no arroz orgânico foram com sementes, combustível, tratores, máquinas e implementos agrícolas e para o arroz convencional foram sementes, combustível e fertilizantes. Para cada 1 kg de grãos dos sistemas orgânicos e convencional são emitidos respectivamente 0,21 e 0,32 kg de CO2eq durante seus ciclos de produção e entrega no armazém, sendo as sementes, combustíveis e fertilizantes as principais fontes de emissão de CO2eq à atmosfera.(AU)

Volatilization of ammonia in systems of treatment of swine manure with aquatic macrophytes / Volatilização de amônia em sistemas de tratamento de dejetos de suínos com macrófitas aquáticas

The usage of aquatic plants represents an alternative in the treatment of residues originating from swine. In these systems, one of the N removal methods is the ammonium (NH4 +) uptake and volatilization of ammonia (NH3). In this way, the objective of this work was to evaluate the volatilization rates of NH3 in waste treatment systems swine fluids (SSF) with aquatic macrophytes, as well as the concentration of NH 4+ present in the swine fluids. The experiment was carried out at Campus II/UNOESTE. The treatment systems were composed of 16 boxes of PVC and characterized as: T1 = Control sample 50% of SSF/50% of water; T2 = 50% SSF/50% water + Eichhornia crassipes (Mart.) Solms; T3 = 50% SSF/50% water + Pistia stratiotes L.; T4 = 50% SSF/50% water + Salvinia auriculata Aubl. The design was randomized blocks, with 4 treatments and 4 replicates. The hydrogen potential (pH) and the NH4 + content of the effluent were analyzed weekly, and the volatilization of NH 3 by means of collectors installed in each treatment unit. The presence of aquatic macrophytes promoted the reduction of NH4+ concentration and of the pH values of swine fluids, and this resulted in the reduction of NH3 volatilization rates to the environment, with emphasis on the system with Eichhornia crassipes (Mart.) Solms, which presented the lowest rate of volatilization.(AU)

A utilização de plantas aquáticas representa uma alternativa no tratamento de resíduos oriundos da suinocultura. Nestes sistemas, uma das formas de remoção de nitrogênio (N) é a absorção de amônio (NH4+) pelas plantas, entretanto, também ocorre a volatilização de amônia (NH3). Dessa forma, o objetivo do trabalho foi avaliar as taxas de volatilização de NH3 em sistemas de tratamentos de dejetos líquidos de suínos (DLS) com macrófitas aquáticas, bem como a concentração de NH4+ presente nos dejetos. O experimento foi realizado em área de ambiente aberto no Campus II/UNOESTE. Os sistemas de tratamento foram constituídos de 16 caixas de PVC e caracterizados como: T1 = Testemunha 50% de DLS/50% de água; T2 = 50% de DLS/50% de água + Eichhornia crassipes (Mart.) Solms; T3 = 50% de DLS/50% de água + Pistia stratiotes L.; T4 = 50% de DLS/50% de água + Salvinia auriculata Aubl. O delineamento adotado foi em blocos casualizados, com 4 tratamentos e 4 repetições. Foram analisados o potencial hidrogeniônico (pH) e o teor de NH4 + do efluente semanalmente, e a volatilização de NH3 por meio de coletores instalados em cada unidade de tratamento. A presença das macrófitas aquáticas proporcionou a redução da concentração de NH4+ e dos valores de pH dos dejetos líquidos de suínos, e isto resultou na redução das taxas de volatilização de NH 3 ao meio ambiente, com destaque ao sistema com Eichhornia crassipes (Mart.) Solms, que apresentou a menor taxa de volatilização.(AU)

Local food: benefits and failings due to modern agriculture

This paper aims to examine the issue raised by the consumption of locally produced food in all its various aspects, and in particular, addresses how this practice contributes to local and global sustainability. It analyzes the different definitions of local food, the strategies used, the implications of the distance traveled in the transportation of food to the consumer's table food miles, the relationships between local food consumption and sustainability, farming practices that reduce carbon emissions, contribution of urban agriculture to local food, local trading of food produced by rural farmers, as well as a number of relationships between the consumption of local food and human nutrition and health, local food protection and the ability to support local food production for humanitarian actions in disaster situations. The promotion of local food is a complex problem covering environmental issues, the economy and health. Transportation is not the only factor that determines how efficient it is to consume local food. Often, the technologies used for agricultural production are those most responsible for the degree of sustainability in the production and supply of food to the population. Local production does not always mean lower emissions of greenhouse gases. In general, the consumption of local foods, produced in ways adapted to the local environment using technologies with an ecological basis, is something beneficial and salutary for the environment, economy and society in general.

Local food: benefits and failings due to modern agriculture

This paper aims to examine the issue raised by the consumption of locally produced food in all its various aspects, and in particular, addresses how this practice contributes to local and global sustainability. It analyzes the different definitions of local food, the strategies used, the implications of the distance traveled in the transportation of food to the consumer's table food miles, the relationships between local food consumption and sustainability, farming practices that reduce carbon emissions, contribution of urban agriculture to local food, local trading of food produced by rural farmers, as well as a number of relationships between the consumption of local food and human nutrition and health, local food protection and the ability to support local food production for humanitarian actions in disaster situations. The promotion of local food is a complex problem covering environmental issues, the economy and health. Transportation is not the only factor that determines how efficient it is to consume local food. Often, the technologies used for agricultural production are those most responsible for the degree of sustainability in the production and supply of food to the population. Local production does not always mean lower emissions of greenhouse gases. In general, the consumption of local foods, produced in ways adapted to the local environment using technologies with an ecological basis, is something beneficial and salutary for the environment, economy and society in general.(AU)

Volatilization of ammonia in systems of treatment of swine manure with aquatic macrophytes

Abstract The usage of aquatic plants represents an alternative in the treatment of residues originating from swine. In these systems, one of the N removal methods is the ammonium (NH4 +) uptake and volatilization of ammonia (NH3). In this way, the objective of this work was to evaluate the volatilization rates of NH3 in waste treatment systems swine fluids (SSF) with aquatic macrophytes, as well as the concentration of NH 4+ present in the swine fluids. The experiment was carried out at Campus II/UNOESTE. The treatment systems were composed of 16 boxes of PVC and characterized as: T1 = Control sample 50% of SSF/50% of water; T2 = 50% SSF/50% water + Eichhornia crassipes (Mart.) Solms; T3 = 50% SSF/50% water + Pistia stratiotes L.; T4 = 50% SSF/50% water + Salvinia auriculata Aubl. The design was randomized blocks, with 4 treatments and 4 replicates. The hydrogen potential (pH) and the NH4 + content of the effluent were analyzed weekly, and the volatilization of NH 3 by means of collectors installed in each treatment unit. The presence of aquatic macrophytes promoted the reduction of NH4+ concentration and of the pH values of swine fluids, and this resulted in the reduction of NH3 volatilization rates to the environment, with emphasis on the system with Eichhornia crassipes (Mart.) Solms, which presented the lowest rate of volatilization.

Resumo A utilização de plantas aquáticas representa uma alternativa no tratamento de resíduos oriundos da suinocultura. Nestes sistemas, uma das formas de remoção de nitrogênio (N) é a absorção de amônio (NH4+) pelas plantas, entretanto, também ocorre a volatilização de amônia (NH3). Dessa forma, o objetivo do trabalho foi avaliar as taxas de volatilização de NH3 em sistemas de tratamentos de dejetos líquidos de suínos (DLS) com macrófitas aquáticas, bem como a concentração de NH4+ presente nos dejetos. O experimento foi realizado em área de ambiente aberto no Campus II/UNOESTE. Os sistemas de tratamento foram constituídos de 16 caixas de PVC e caracterizados como: T1 = Testemunha 50% de DLS/50% de água; T2 = 50% de DLS/50% de água + Eichhornia crassipes (Mart.) Solms; T3 = 50% de DLS/50% de água + Pistia stratiotes L.; T4 = 50% de DLS/50% de água + Salvinia auriculata Aubl. O delineamento adotado foi em blocos casualizados, com 4 tratamentos e 4 repetições. Foram analisados o potencial hidrogeniônico (pH) e o teor de NH4 + do efluente semanalmente, e a volatilização de NH3 por meio de coletores instalados em cada unidade de tratamento. A presença das macrófitas aquáticas proporcionou a redução da concentração de NH4+ e dos valores de pH dos dejetos líquidos de suínos, e isto resultou na redução das taxas de volatilização de NH 3 ao meio ambiente, com destaque ao sistema com Eichhornia crassipes (Mart.) Solms, que apresentou a menor taxa de volatilização.

Volatilization of ammonia in systems of treatment of swine manure with aquatic macrophytes

Abstract The usage of aquatic plants represents an alternative in the treatment of residues originating from swine. In these systems, one of the N removal methods is the ammonium (NH4 +) uptake and volatilization of ammonia (NH3). In this way, the objective of this work was to evaluate the volatilization rates of NH3 in waste treatment systems swine fluids (SSF) with aquatic macrophytes, as well as the concentration of NH 4+ present in the swine fluids. The experiment was carried out at Campus II/UNOESTE. The treatment systems were composed of 16 boxes of PVC and characterized as: T1 = Control sample 50% of SSF/50% of water; T2 = 50% SSF/50% water + Eichhornia crassipes (Mart.) Solms; T3 = 50% SSF/50% water + Pistia stratiotes L.; T4 = 50% SSF/50% water + Salvinia auriculata Aubl. The design was randomized blocks, with 4 treatments and 4 replicates. The hydrogen potential (pH) and the NH4 + content of the effluent were analyzed weekly, and the volatilization of NH 3 by means of collectors installed in each treatment unit. The presence of aquatic macrophytes promoted the reduction of NH4+ concentration and of the pH values of swine fluids, and this resulted in the reduction of NH3 volatilization rates to the environment, with emphasis on the system with Eichhornia crassipes (Mart.) Solms, which presented the lowest rate of volatilization.

Resumo A utilização de plantas aquáticas representa uma alternativa no tratamento de resíduos oriundos da suinocultura. Nestes sistemas, uma das formas de remoção de nitrogênio (N) é a absorção de amônio (NH4+) pelas plantas, entretanto, também ocorre a volatilização de amônia (NH3). Dessa forma, o objetivo do trabalho foi avaliar as taxas de volatilização de NH3 em sistemas de tratamentos de dejetos líquidos de suínos (DLS) com macrófitas aquáticas, bem como a concentração de NH4+ presente nos dejetos. O experimento foi realizado em área de ambiente aberto no Campus II/UNOESTE. Os sistemas de tratamento foram constituídos de 16 caixas de PVC e caracterizados como: T1 = Testemunha 50% de DLS/50% de água; T2 = 50% de DLS/50% de água + Eichhornia crassipes (Mart.) Solms; T3 = 50% de DLS/50% de água + Pistia stratiotes L.; T4 = 50% de DLS/50% de água + Salvinia auriculata Aubl. O delineamento adotado foi em blocos casualizados, com 4 tratamentos e 4 repetições. Foram analisados o potencial hidrogeniônico (pH) e o teor de NH4 + do efluente semanalmente, e a volatilização de NH3 por meio de coletores instalados em cada unidade de tratamento. A presença das macrófitas aquáticas proporcionou a redução da concentração de NH4+ e dos valores de pH dos dejetos líquidos de suínos, e isto resultou na redução das taxas de volatilização de NH 3 ao meio ambiente, com destaque ao sistema com Eichhornia crassipes (Mart.) Solms, que apresentou a menor taxa de volatilização.

Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

Water management impacts both methane (CH4) and nitrous oxide (N2O) emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30); and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI). AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p > 0.05). No yield differences between irrigation systems were observed in two of the rice seasons ( p > 0.05) while AWDI promoted yield reduction in one of the seasons ( p 0.05). When rice yield and greenhouse gases (GHG) emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP). Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers.

Global Challenges for the 21st Century: the Role and Strategy of the Agri-Food Sector

Human activity is having an increasing global impact on the environment, geology and ecosystems. There is an 80% probability that world population will increase to between 9.6 billion and 12.3 billion by 2100 and could even reach 10 billion by 2056, 6 years earlier than projected. Historically, global production of food has outpaced consumption growth. This is evidenced by falling real prices of food, however this is now slowing, caused by constraints on supply and continued growth of demand. Paradoxically, as billions suffer food insecurity through lack of food, more than 2 billion people, approximately 30% of the world’s population, are overweight or obese and this percentage continues to grow. It is also estimated that the world will need to close a significant food-gap by 2050, primarily because of continued population growth and changing diets. Increases in temperature of over two degrees Celsius are projected to have a negative impact on global yields of major crops. Agri-food production, including manufacture, food preparation and cooking, accounts for approximately 30% of all greenhouse-gas emissions and livestock production accounts for approximately 50% of this. The agricultural sector will increasingly be driven by these global changes, including a rising world population, rapid development of emerging economies, with western lifestyle aspirations, growing geopolitical instability around shortages of land, water and energy and ‘one health’ issues. However, a technological revolution is taking place, including breakthroughs in nutrition, genetics, informatics, satellite imaging, remote sensing, meteorology, precision farming and low impact agriculture. These changes will hopefully continue to drive major global investment in agricultural technologies. It is of vital importance that countries around the world recognize fully the opportunities and challenges and provide the appropriate framework support, investment and infrastructure...

Global Challenges for the 21st Century: the Role and Strategy of the Agri-Food Sector

Human activity is having an increasing global impact on the environment, geology and ecosystems. There is an 80% probability that world population will increase to between 9.6 billion and 12.3 billion by 2100 and could even reach 10 billion by 2056, 6 years earlier than projected. Historically, global production of food has outpaced consumption growth. This is evidenced by falling real prices of food, however this is now slowing, caused by constraints on supply and continued growth of demand. Paradoxically, as billions suffer food insecurity through lack of food, more than 2 billion people, approximately 30% of the worlds population, are overweight or obese and this percentage continues to grow. It is also estimated that the world will need to close a significant food-gap by 2050, primarily because of continued population growth and changing diets. Increases in temperature of over two degrees Celsius are projected to have a negative impact on global yields of major crops. Agri-food production, including manufacture, food preparation and cooking, accounts for approximately 30% of all greenhouse-gas emissions and livestock production accounts for approximately 50% of this. The agricultural sector will increasingly be driven by these global changes, including a rising world population, rapid development of emerging economies, with western lifestyle aspirations, growing geopolitical instability around shortages of land, water and energy and ‘one health issues. However, a technological revolution is taking place, including breakthroughs in nutrition, genetics, informatics, satellite imaging, remote sensing, meteorology, precision farming and low impact agriculture. These changes will hopefully continue to drive major global investment in agricultural technologies. It is of vital importance that countries around the world recognize fully the opportunities and challenges and provide the appropriate framework support, investment and infrastructure...(AU)

Yield-scaled global warming potential of two irrigation management systems in a highly productive rice system

Water management impacts both methane (CH4) and nitrous oxide (N2O) emissions from rice paddy fields. Although controlled irrigation is one of the most important tools for reducing CH4emission in rice production systems it can also increase N2O emissions and reduce crop yields. Over three years, CH4 and N2O emissions were measured in a rice field in Uruguay under two different irrigation management systems, using static closed chambers: conventional water management (continuous flooding after 30 days of emergence, CF30); and an alternative system (controlled deficit irrigation allowing for wetting and drying, AWDI). AWDI showed mean cumulative CH4 emission values of 98.4 kg CH4 ha1, 55 % lower compared to CF30, while no differences in nitrous oxide emissions were observed between treatments ( p > 0.05). No yield differences between irrigation systems were observed in two of the rice seasons ( p > 0.05) while AWDI promoted yield reduction in one of the seasons ( p 0.05). When rice yield and greenhouse gases (GHG) emissions were considered together, the AWDI irrigation system allowed for lower yield-scaled total global warming potential (GWP). Higher irrigation water productivity was achieved under AWDI in two of the three rice seasons. These findings suggest that AWDI could be an option for reducing GHG emissions and increasing irrigation water productivity. However, AWDI may compromise grain yield in certain years, reflecting the importance of the need for fine tuning of this irrigation strategy and an assessment of the overall tradeoff between relationships in order to promote its adoption by farmers.(AU)

EMISSÕES DE AMÔNIA, ÓXIDO NITROSO E METANO DE EXCRETAS DE BOVINOS CONFINADOS RECEBENDO DIETAS COM PROTEÍNA NÃO DEGRADÁVEL NO RÚMEN

A inclusão de níveis mais elevados de proteína não degradável no rúmen (PNDR) em dietas para bovinos é adotada como estratégia para melhorar a eficiência do uso de aminoácidos e reduzir a excreção de nitrogênio (N) no meio ambiente. Assim, é necessário avaliar o efeito de fontes de PNDR em dietas sobre as emissões de metano (CH4) e óxido nitroso (N2O) e amônia (NH3) nas excretas de bovinos criados em confinamento. A hipótese avaliada foi que o uso de fontes de PNDR na dieta dos animais poderia reduzir a eliminação de N pela urina e contribuir para a redução de N2O, CH4 e NH3 no meio ambiente. O delineamento experimental utilizado foi inteiramente casualizado com nove repetições por baia (câmaras de avaliações de N2O, CH4 e NH3 das excretas, considerando fezes e urina) dispostas em uma área de 65m2, próximo aos comedouros, onde o esterco foi depositado mais frequentemente. As excretas avaliadas foram provenientes de animais Nelore alimentados com três tratamentos: Farelo de Soja Protegido (FSP, fonte PNDR), Glúten de Milho (GM, fonte PNDR), ou Farelo de Soja (FS, fonte de PDR,). O confinamento teve duração de 112 dias, durante os quais foram realizadas as coletas semanais de N2O e CH4. Após a saída dos animais do confinamento, foi realizada coleta de NH3 durante 77 dias. As fontes proteicas utilizadas na dieta não afetaram a concentração de N e C na urina, a concentração de C nas fezes e o balanço de N (P> 0,05). Houve uma relação C/N mais elevada de fezes (P < 0.001) e urina (P < 0.001) na fonte FSP do que a fonte GM e uma concentração mais elevada de N nas fezes na fonte GM do que na fonte FSP (P = 0,012). O esterco de animais alimentados com fontes PNDR (GM e FSP) apresentou maior concentração de N (P = 0,036) e amônio (P = 0.001) em relação à fonte de FS. Porém, as fontes PNDR apresentaram menor relação C/N em relação à fonte FS (P = 0,001. As fontes PNDR resultaram em maior emissão de N2O do que a fonte PDR (P = 0,030), enquanto FSP resultou em maior emissão de N2O do que GM (P = 0,038) (FS = 633, FSP = 2521 e GM = 1153 g ha-2 N-N2O); entretanto, não houve diferenças nas emissões de CH4 e NH3 (P> 0,05). Em conclusão, o uso de PNDR em dietas não afetou a excreção de N dos animais ou a emissão de CH4 e NH3 do esterco, mas aumentou a emissão de N2O do esterco.

The inclusion of higher levels of rumen undegradable protein (RUP) in bovine diet is adopted as a strategy to improve the efficiency use of amino acids, and reduce nitrogen (N) excretion to the environment. Thus, it is necessary to evaluate the effect of sources of RUP in diets on methane (CH4), nitrous oxide (N2O) and ammonia (NH3) emissions in the manure of feedlot-finished cattle. The evaluated hypothesis was that the use of different RUP sources in diet would reduce N loss via urine and contribute to a reduced N2O, CH4 and NH3 emission to the environment. The experimental design was completely randomized, with nine replicates per pen (chambers for the evaluation of N2O, CH4 and NH3 emissions from manure, considering feces and urine), arranged in an area of 65 m2, near the feeders, where the manure was deposited the most frequently. Manure came from Nellore animals fed with three treatments as follows: soybean meal (SM, RDP source), by-pass soybean meal (BSM, RUP source) and corn gluten meal (CGM, RUP source). The confinement lasted 112 days, during which weekly samplings of N2O and CH4 were performed. After removing the animals from feedlots, NH3 emission was evaluated during 77 days. The protein sources used in the diet did not affect the N and C concentration in urine, C concentration in feces, and N balance (P > 0.05). There was a higher C/N of feces (P < 0.001) and urine (P < 0.001) in the BSM source than the CGM source and a higher concentration of N in the feces in the CGM source than the BSM source (P = 0.012). The manure from animals fed with sources of RUP (BSM and CGM) presented higher concentration of N (P = 0.036) and ammonium (P = 0.001) compared to SM source. However, RUP sources presented lower C/N in relation to SM source (P = 0.001). The RUP sources resulted in a higher N2O emission than the RDP source (P = 0.030), while BSM resulted in a higher N2O emission than CGM (P = 0.038) (SM = 633, BSM = 2521, and CGM = 1153 g ha-2 N-N2O); however, there were no differences in CH4 and NH3 emissions (P > 0.05) In conclusion, the use of RUP in diets did not affect N excretion of animals or CH4 and NH3 emission from manure, but increased N2O emission from the manure

Factors affecting mitigation of methane emission from ruminants: Microbiology and biotechnology strategies / Fatores que afetam a mitigação das emissões de metano a partir de ruminantes: Estratégias de microbiologia e biotecnologia

Climate change is a subject of global environmental concern. Increased anthropogenic Greenhouse Gas (GHG) emissions have increased the global temperature the last 100 to 200 years. Carbon dioxide and methane are the main greenhouse gases related to animal nutrition and methane has greater global warming potential than carbon dioxide. Among greenhouse gases, methane is considered a potent greenhouse gas with 21 times more global warming potential than carbon dioxide. Worldwide, ruminant livestock produce about 80 million metric tons of methane each year, accounting for about 28% of global emissions from human related activities. Therefore it is impelling animal scientists to finding solutions to mitigate methane emission from ruminants. It seems that solutions can be discussed in four topics including: nutrition (feeding), biotechnology, microbiology and management strategies. We have already published the first and second review articles on feeding strategies and management strategies. In the current review, Microbiology and biotechnology such as emphasizing on animal  breeding, genetic merit, bovine somatotropin (BST), unproductive animals, vaccination, immunisation and biological control (bacteriophage, acetogenesis reductive), chemical defaunation that can be leads to decreasing methane production from ruminant animal production are discussed.(AU)

A mudança climática é um assunto de preocupação ambiental global. O aumento dos gases de estufa antropogênicos (GEA) tem elevado a temperatura global nos últimos 100 a 200 anos. O dióxido de carbono e metano são os principais gases do efeito estufa e estão relacionados com a nutrição animal, onde o metano tem maior potencial de aquecimento global do que o dióxido de carbono. Entre os gases do efeito estufa, o metano é considerado um gás 21 vezes com maior potencial de aquecimento global do que o dióxido de carbono. Em todo o mundo, animais ruminantes produzem cerca de 80 milhões de toneladas de metano por ano, respondendo por cerca de 28% das emissões globais das atividades humanas relacionadas. Por isso é impelindo aos zootecnistas encontrar soluções para mitigar emissões de metano a partir de ruminantes. Parece que as soluções podem ser discutidas em quatro temas, incluindo: nutrição (alimentação), biotecnologia, microbiologia e estratégias de gestão. Nós já publicamos o primeiro e segundo artigos de revisão sobre estratégias de alimentação e estratégias de gestão. Na avaliação atual, microbiologia e biotecnologia, tal como com ênfase na criação de animais, mérito genético, somatotropina bovina (BST), animais improdutivos, vacinação, imunização e controle biológico (bacteriófago, acetogênese redutora), defaunação química que pode conduz à diminuição da produção de metano na produção de ruminantes são discutidos.(AU)

RESPOSTA PRODUTIVA DO CAPIM-MASSAI E FLUXO DE GASES DO SOLO EM SISTEMA SILVIPASTORIL COM APLICAÇÃO DE BIOESTIMULANTE FOLIAR

O uso de componentes arbóreos em sistemas de pastagens tem sido utilizado para trazer diversos benefícios ao componente solo-planta-animal, podendo alterar o valor nutricional das forragens e as emissões de gases de efeito do solo estufa do sistema. Diante disso, a presente Tese teve como objetivo i) avaliar massa de forragem e valor nutritivo do capim-massai em sistema silvipastoril (SSP) ou a pleno sol (SPS) durante os diferentes estádios de desenvolvimento (ED) e, ii) quantificar a emissão de gases de efeito estufa do solo do capim-massai em SSP ou SPS sob a aplicação de bioestimulante foliar. Para isso, dois experimentos foram desenvolvidos. No experimento 1 o delineamento experimental foi inteiramente casualizado, com cinco repetições. Os tratamentos foram distribuídos em esquema fatorial 2 x 4. O capim-massai foi avaliado em dois tipos de sistemas: SSP e SPS; durante quatro estádios de desenvolvimento: estádio vegetativo (E1), pré-floração (E2), floração plena (E3) e maturidade após o florescimento (E4). O componente florestal do sistema silvipastoril foi o Eucalyptus urograndis (Eucalyptus grandis x Eucalyptus urophylla), plantados em fileiras únicas, no sentido Leste-Oeste e espaçamentos de 18 x 1,5 m. O experimento 2 foi disposto em delineamento inteiramente casualizado, com cinco repetições, em esquema fatorial 2 x 2, em 4 ciclos de pastejo. Os tratamentos foram os dois sistemas: SSP e SPS; e aplicação do bioestimulante foliar: com e sem. No experimento 1, a produção de massa de forragem e componentes morfológicos do capim-massai não diferiram (p>0,05) entre o SSP e SPS. Entretanto, se diferiram nos estádios de desenvolvimento (p<0,05), com efeito linear crescente para massa de forragem, porcentagem de colmo e material morto e decrescente para porcentagem de folha e relação folha:colmo. O tipo de sistema de cultivo alterou apenas o teor de proteína bruta. À medida que se elevou a idade da planta forrageira, houve redução na produção de gás oriundo da fermentação da matéria orgânica (Vf) e tempo de colonização (L). A degradabilidade in vitro da matéria seca não diferiu entres os sistemas de cultivo e decaiu com o avançar dos estádios de desenvolvimento. No experimento 2, as maiores emissões e consumos de metano (CH4) ocorreram no 4° ciclo de pastejo, em ambos os anos experimentais com fluxo médio de 149 ± 64 g CH4 m-2 h-1 e -122 ± 73 g CH4 m-2 h- iv 1, respectivamente. Os maiores fluxos de óxido nitroso (N2O) foram observados no 1° ciclo de pastejo nos dois anos experimentais com fluxo médio de 80 ± 70 g N2O m-2 h-1 e 62 ± 21 N2O g m-2 h-1 em 2020. Independentemente do tipo dos sistemas e a aplicação do bioestimulante não houve alteração nas emissões cumulativas de CH4. Em relação ao N2O, a aplicação do bioestimulante foliar reduziu a emissão cumulativa de N2O no 2° ciclo de pastejo e durante o 3° ciclo de pastejo o SSP apresentou maior emissão. No experimento 1, o sombreamento causado pelo sistema silvipastoril não comprometeu a massa de forragem, valor nutritivo e a DIVMS do capim-massai em comparação ao sistema a pleno sol, exceto pelo aumento no teor de PB. O sombreamento também fez com que o capim-massai permanecesse estádio vegetativo por mais tempo. O avanço do estádio de desenvolvimento da forrageira resulta na diminuição da proporção de folhas e do seu valor nutritivo. No experimento 2, Pastagens tropicais funcionam como fonte e dreno nas emissões de N2O e CH4. Os resultados demonstram que o sistema silvipastoril possui potencial para emitir mais N2O em comparação ao sistema em monocultivo, enquanto a aplicação de bioestimulante foliar apresenta potencial para reduzir essas emissões. No entanto, outros fatores que controlam os fluxos dos gases de efeito estufa vão além do sistema e uso de bioestimulante foliar. Estudos futuros devem ser realizados para verificar quais são os principais controladores na emissão de gases de efeito estufa em diferentes sistemas de pastagens tropicais e diferentes doses de bioestimulantes.

The use of arboreal components in pasture systems has been used to bring several benefits to the soil-plant-animal component, which can alter the nutritional value of forages and the system's greenhouse gas emissions. Therefore, this Thesis aimed to i) evaluate forage mass and nutritive value of massai grass in a silvopastoral system (SSP) or in full sun (SPS) during the different stages of development (ED) and, ii) quantify the emission of greenhouse gases from the soil of massai grass in SSP or SPS under the application of foliar biostimulant. For this, two experiments were developed. In experiment 1, the experimental design was completely randomized, with five replications. The treatments were distributed in a 2 x 4 factorial scheme. Massai grass was evaluated in two types of systems: SSP and SPS; during four developmental stages: vegetative stage (E1), pre-flowering (E2), full flowering (E3) and maturity after flowering (E4). The forest component of the silvopastoral system was the Eucalyptus urograndis (Eucalyptus grandis x Eucalyptus urophylla), planted in single rows, in the East-West direction and spacing of 18 x 1.5 m. Experiment 2 was arranged in a completely randomized design, with five replications, in a 2 x 2 factorial scheme, in 4 grazing cycles. The treatments were the two systems: SSP and SPS; and application of the foliar biostimulant: with and without. In experiment 1, forage mass production and morphological components of massai grass did not differ (p>0.05) between SSP and SPS. However, they differed in the development stages (p<0.05), with an increasing linear effect for forage mass, percentage of stem and dead material and decreasing for leaf percentage and leaf:stem ratio. The type of cultivation system only changed the crude protein content. As the age of the forage plant increased, there was a reduction in gas production from the fermentation of organic matter (Vf) and colonization time (L). The in vitro degradability of dry matter did not differ between cropping systems and declined as the development stages progressed. In experiment 2, the highest emissions and consumption of methane (CH4) occurred in the 4th grazing cycle, in both experimental years with an average flow of 149 ± 64 g CH4 m-2 h-1 and -122 ± 73 g CH4 m-2 h-1, respectively. The highest fluxes of nitrous oxide (N2O) were observed in the 1st grazing cycle in the two experimental years with a mean flux of vi 80 ± 70 g N2O m-2 h-1 and 62 ± 21 N2O g m-2 h-1 in 2020 Regardless of the type of systems and the application of the biostimulant, there was no change in cumulative CH4 emissions. In relation to N2O, the application of the foliar biostimulant reduced the cumulative emission of N2O in the 2nd grazing cycle and during the 3rd grazing cycle the SSP presented higher emission. In experiment 1, the shading caused by the silvopastoral system did not affect the forage mass, nutritive value and DIVMS of massai grass compared to the system under full sun, except for the increase in CP content. Shading also made the Massai grass remain a vegetative stage for a longer period of time. The advancement of the forage development stage results in a decrease in the proportion of leaves and their nutritive value. In experiment 2, tropical pastures act as a source and sink for N2O and CH4 emissions. The results demonstrate that the silvopastoral system has the potential to emit more N2O compared to the monoculture system, while the application of foliar biostimulant has the potential to reduce these emissions. However, other factors that control the fluxes of greenhouse gases go beyond the foliar biostimulant system and use. Future studies must be carried out to verify which are the main controllers in the emission of greenhouse gases in different tropical pasture systems and different doses of biostimulants.