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1.
Sci. agric ; 80: e20210142, 2023. ilus, tab, mapa, graf
Artigo em Inglês | VETINDEX | ID: biblio-1367270

Resumo

Adaptation to climate change is a strategy for crops to cope with the scenario of rising temperatures worldwide. In the case of Coffea arabica L., the use of agroforestry systems (AFS) with woody species is a promising practice to reduce excessive heat during the day. This study aimed to 1) evaluate air temperature changes that occur in an AFS of coffee and double alleys of rubber trees (Hevea brasiliensis Müell. Arg.) and 2) carry out an analysis of future warming scenarios by comparing the cultivation of Arabic coffee in full sun and in an AFS of double alleys of rubber trees. The microclimatic variables were measured between two rows of coffee trees at 1.0 m of height from June 2016 to June 2018. The results indicate that the AFS with double alleys of rubber trees spaced 16 m apart had an average temperature reduction from 1.4 to 2.5 °C from 10h00 to 16h00. The study also simulated temperature increases of 1.7, 2.6, 3.1, and 4.8 °C from 2018 to 2099, according to scenarios predicted by the Intergovernmental Panel on Climate Change (IPCC), and the impact in coffee production in Paraná State, Brazil. Using the climatic generator PGECLIMA_R, simulations suggest a progressive reduction of traditional areas suitable for open-grown coffee in the state. Production conditions can be maintained through the AFS, since the systems attenuate mean temperatures by 1-2 °C. We conclude that the AFS of coffee and rubber trees contribute to coffee crop adaptations to a future warmer environment.


Assuntos
Mudança Climática/estatística & dados numéricos , Adaptação Fisiológica , Hevea , Coffea/crescimento & desenvolvimento , Florestas
2.
Sci. agric. ; 78(6): 1-10, 2021. graf, ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-31248

Resumo

Land use and tillage practices may change soil structure and undermine sustainable agriculture; however, such changes are hardly identified in the short term. In this sense, agroforestry systems have been used to reduce soil degradation and promote sustainable production in coffee plantations. These areas are expected to have well-structured soils and hence improved root distribution. This study aimed to evaluate soil quality by the morphostructural and root distribution analyses comparing open-grown coffee and coffee in agroforestry systems with rubber trees for 19 years, in an Oxisol in northern Paraná State (Brazil). Treatments consisted of open-grown coffee (OG), coffee partially shaded by rubber trees (PSH), and coffee fully shaded by rubber trees (FSH). The mapping of morphostructural features and soil resistance to penetration in cultural profile walls identified changes in soil structure resulting from different tillage systems. Root distribution was better in coffee plants grown in PSH and FSH systems. At greater depths, cultural profiles of FSH and PSH showed a larger numbers of roots compared to OG. Among the three systems, PSH provided a better environment for root growth and distribution. This result could be attributed to the high biological activity and interaction between roots and aggregates in that profile. The FSH agroforestry system provided less compact morphological structures and more roots throughout the soil profile. The agroforestry systems presented fewer soil structural changes by tillage operations and lower values of soil penetration resistance. Coffee root distribution was an effective indicator of soil quality and consistent with the morphostructural characterization of cultural profile.(AU)


Assuntos
Solo/química , Agricultura Sustentável/métodos , Café
3.
Sci. agric ; 78(6): 1-10, 2021. graf, ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497990

Resumo

Land use and tillage practices may change soil structure and undermine sustainable agriculture; however, such changes are hardly identified in the short term. In this sense, agroforestry systems have been used to reduce soil degradation and promote sustainable production in coffee plantations. These areas are expected to have well-structured soils and hence improved root distribution. This study aimed to evaluate soil quality by the morphostructural and root distribution analyses comparing open-grown coffee and coffee in agroforestry systems with rubber trees for 19 years, in an Oxisol in northern Paraná State (Brazil). Treatments consisted of open-grown coffee (OG), coffee partially shaded by rubber trees (PSH), and coffee fully shaded by rubber trees (FSH). The mapping of morphostructural features and soil resistance to penetration in cultural profile walls identified changes in soil structure resulting from different tillage systems. Root distribution was better in coffee plants grown in PSH and FSH systems. At greater depths, cultural profiles of FSH and PSH showed a larger numbers of roots compared to OG. Among the three systems, PSH provided a better environment for root growth and distribution. This result could be attributed to the high biological activity and interaction between roots and aggregates in that profile. The FSH agroforestry system provided less compact morphological structures and more roots throughout the soil profile. The agroforestry systems presented fewer soil structural changes by tillage operations and lower values of soil penetration resistance. Coffee root distribution was an effective indicator of soil quality and consistent with the morphostructural characterization of cultural profile.


Assuntos
Agricultura Sustentável/métodos , Solo/química , Café
4.
Semina Ci. agr. ; 36(6): 3567-3578, nov.-dez. 2015. tab, graf, mapas
Artigo em Inglês | VETINDEX | ID: vti-30331

Resumo

The objective of this study was to evaluate the biomass production of elephant grass and leucaena in Paraná state, Brazil, for the generation of renewable energy. Two field studies were conducted in the municipality of Ibiporã (23 S, 51 01?W). In the first study, the dry matter accumulation curves were calculated, with sampling at 30, 60, 90, 120, and 180 days after cultivation. The second study was conducted in a randomized complete block design with split plots. The total aboveground biomass production of elephant grass and leucaena was estimated in the main plot. Cutting times of 60 and 120 days after cultivation were evaluated in the subplots. The productivity of dry matter (kg.ha-1) was estimated using the biomass data. In addition, the potential production of energy from the burning of elephant grass biomass, and the potential production of total aboveground biomass and energy of elephant grass (in Paraná) was estimated using an agrometeorological model. Elephant grass can be potentially used as an alternative energy source. Leucaena has slow initial growth, and it must therefore be evaluated over a longer period in order to determine its potential. Simulation analyses of the capability of power generation, conducted based on the annual dry matter production, revealed that elephant grass could be an important source of renewable energy in the state of Paraná.(AU)


O objetivo deste estudo foi avaliar a produção de biomassa de capim elefante e leucena no estado do Paraná visando à geração de energia. Foram conduzidos dois estudos de campo no município de Ibiporã, PR (23o S, 51o 01 W). No primeiro, determinaram-se as curvas de acúmulo de matéria seca da parte aérea com coletas aos 30, 60, 90, 120 e 180 dias após o plantio. No segundo, foi conduzido um experimento em blocos ao acaso, com parcelas subdivididas. Na parcela principal foi avaliada a produção total de biomassa da parte aérea de capim elefante e leucena. Nas subparcelas foram avaliadas as épocas de corte aos 60 e 120 dias de cultivo. Com os dados de biomassa determinaram-se a produtividade total de massa seca da parte aérea (kg/ha) e o potencial de produção de energia proveniente da queima da biomassa do capim elefante, e fez-se a estimativa da produção potencial de biomassa e energia de capim elefante no Paraná utilizando um modelo agrometeorológico. O capim elefante possui características que possibilitam a sua utilização como fonte alternativa de energia. A leucena possui crescimento inicial lento e, portanto, requer estudos por um período mais prolongado a fim de se determinar o seu potencial. As análises de simulação de potencialidade de geração de energia, em função da matéria seca produzida anualmente, mostraram que o capim elefante pode se constituir em uma importante...(AU)


Assuntos
Pennisetum , Energia Renovável , Biomassa , Fontes Geradoras de Energia
5.
Semina Ci. agr. ; 36(6): 3665-3670, nov.-dez. 2015. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-30399

Resumo

Emphasis on studies that seek sustainable energy alternatives to oil has increased over the last few years. Ethanol derived from sugarcane remains a promising technology for biofuel production. Waste from pineapple culture remains is a potential alternative raw material for biofuel production. The goal of this study was to determine the potential of residual biomass production of a pineapple crop, subjected to fertilization by different levels of nitrogen and potassium. The experiment was conducted in Northwest Paraná, in a commercial area in Santa Isabel do Ivaí-PR. The climate in this area is subtropical humid according to the Kõppen classification, and has a sandy dystrophic red acrisol.The experimental design was a 4 × 4 factorial, where factor A:N doses (0; 11; 22; and 33 g per plant) and factor B:K2O doses (0; 11; 22; and 33 g per plant. The production of residual pineapple biomass responded differently to the N and K doses applied. Potassium fertilization had a positive linear correlation, up to the addition of 33 g plant-1 with a production of 5.88 Mg ha-1. A dose of 18.138 g plant-1 yielded in the maximum dry biomass production for nitrogen fertilization.(AU)


Nos últimos anos intensificou-se a ênfase em estudos e pesquisas na busca de energias alternativas sustentáveis em relação ao petróleo. O etanol proveniente dos restos culturais tornou-se uma tecnologia promissora para produção de biocombustíveis. Dentre os resíduos agrícolas, os restos culturais do abacaxizeiro destacam-se como matéria-prima alternativa para este propósito. O objetivo deste trabalho foi determinar o potencial de produção de biomassa residual de uma lavoura de abacaxi, submetida a diferentes níveis de adubação nitrogenada e potássica. O experimento foi realizado na região Noroeste do Paraná, em uma área comercial em Santa Isabel do Ivaí-PR, de clima subtropical úmido segundo a classificação de Kõppen, em um Argissolo Vermelho distrófico de textura arenosa. O delineamento experimental foi constituído em um fatorial 4x4, sendo o fator A: doses de N (0; 11; 22; e 33 g planta-1) e fator B: doses de K2O (0; 11; 22; e 33 g planta-1). A produção de biomassa residual de abacaxi apresentou respostas distintas às doses aplicadas de N e K na região noroeste do Paraná. A adubação potássica apresentou resposta linear crescente até 33 g planta-1 com produção de 5,88 Mg ha-1. Para a adubação nitrogenada a máxima produção de massa seca foi obtida com aplicação da dose de 18,138 g planta-1.(AU)


Assuntos
Biomassa , Ananas/efeitos dos fármacos , Nitrogênio/administração & dosagem , Potássio/administração & dosagem , Fertilizantes
6.
Semina ciênc. agrar ; 36(6): 3567-3578, 2015. tab, graf, map
Artigo em Inglês | VETINDEX | ID: biblio-1500133

Resumo

The objective of this study was to evaluate the biomass production of elephant grass and leucaena in Paraná state, Brazil, for the generation of renewable energy. Two field studies were conducted in the municipality of Ibiporã (23 S, 51 01?W). In the first study, the dry matter accumulation curves were calculated, with sampling at 30, 60, 90, 120, and 180 days after cultivation. The second study was conducted in a randomized complete block design with split plots. The total aboveground biomass production of elephant grass and leucaena was estimated in the main plot. Cutting times of 60 and 120 days after cultivation were evaluated in the subplots. The productivity of dry matter (kg.ha-1) was estimated using the biomass data. In addition, the potential production of energy from the burning of elephant grass biomass, and the potential production of total aboveground biomass and energy of elephant grass (in Paraná) was estimated using an agrometeorological model. Elephant grass can be potentially used as an alternative energy source. Leucaena has slow initial growth, and it must therefore be evaluated over a longer period in order to determine its potential. Simulation analyses of the capability of power generation, conducted based on the annual dry matter production, revealed that elephant grass could be an important source of renewable energy in the state of Paraná.


O objetivo deste estudo foi avaliar a produção de biomassa de capim elefante e leucena no estado do Paraná visando à geração de energia. Foram conduzidos dois estudos de campo no município de Ibiporã, PR (23o S, 51o 01 W). No primeiro, determinaram-se as curvas de acúmulo de matéria seca da parte aérea com coletas aos 30, 60, 90, 120 e 180 dias após o plantio. No segundo, foi conduzido um experimento em blocos ao acaso, com parcelas subdivididas. Na parcela principal foi avaliada a produção total de biomassa da parte aérea de capim elefante e leucena. Nas subparcelas foram avaliadas as épocas de corte aos 60 e 120 dias de cultivo. Com os dados de biomassa determinaram-se a produtividade total de massa seca da parte aérea (kg/ha) e o potencial de produção de energia proveniente da queima da biomassa do capim elefante, e fez-se a estimativa da produção potencial de biomassa e energia de capim elefante no Paraná utilizando um modelo agrometeorológico. O capim elefante possui características que possibilitam a sua utilização como fonte alternativa de energia. A leucena possui crescimento inicial lento e, portanto, requer estudos por um período mais prolongado a fim de se determinar o seu potencial. As análises de simulação de potencialidade de geração de energia, em função da matéria seca produzida anualmente, mostraram que o capim elefante pode se constituir em uma importante...


Assuntos
Biomassa , Energia Renovável , Fontes Geradoras de Energia , Pennisetum
7.
Semina ciênc. agrar ; 36(6): 3665-3670, 2015. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1500168

Resumo

Emphasis on studies that seek sustainable energy alternatives to oil has increased over the last few years. Ethanol derived from sugarcane remains a promising technology for biofuel production. Waste from pineapple culture remains is a potential alternative raw material for biofuel production. The goal of this study was to determine the potential of residual biomass production of a pineapple crop, subjected to fertilization by different levels of nitrogen and potassium. The experiment was conducted in Northwest Paraná, in a commercial area in Santa Isabel do Ivaí-PR. The climate in this area is subtropical humid according to the Kõppen classification, and has a sandy dystrophic red acrisol.The experimental design was a 4 × 4 factorial, where factor A:N doses (0; 11; 22; and 33 g per plant) and factor B:K2O doses (0; 11; 22; and 33 g per plant. The production of residual pineapple biomass responded differently to the N and K doses applied. Potassium fertilization had a positive linear correlation, up to the addition of 33 g plant-1 with a production of 5.88 Mg ha-1. A dose of 18.138 g plant-1 yielded in the maximum dry biomass production for nitrogen fertilization.


Nos últimos anos intensificou-se a ênfase em estudos e pesquisas na busca de energias alternativas sustentáveis em relação ao petróleo. O etanol proveniente dos restos culturais tornou-se uma tecnologia promissora para produção de biocombustíveis. Dentre os resíduos agrícolas, os restos culturais do abacaxizeiro destacam-se como matéria-prima alternativa para este propósito. O objetivo deste trabalho foi determinar o potencial de produção de biomassa residual de uma lavoura de abacaxi, submetida a diferentes níveis de adubação nitrogenada e potássica. O experimento foi realizado na região Noroeste do Paraná, em uma área comercial em Santa Isabel do Ivaí-PR, de clima subtropical úmido segundo a classificação de Kõppen, em um Argissolo Vermelho distrófico de textura arenosa. O delineamento experimental foi constituído em um fatorial 4x4, sendo o fator A: doses de N (0; 11; 22; e 33 g planta-1) e fator B: doses de K2O (0; 11; 22; e 33 g planta-1). A produção de biomassa residual de abacaxi apresentou respostas distintas às doses aplicadas de N e K na região noroeste do Paraná. A adubação potássica apresentou resposta linear crescente até 33 g planta-1 com produção de 5,88 Mg ha-1. Para a adubação nitrogenada a máxima produção de massa seca foi obtida com aplicação da dose de 18,138 g planta-1.


Assuntos
Ananas/efeitos dos fármacos , Biomassa , Fertilizantes , Nitrogênio/administração & dosagem , Potássio/administração & dosagem
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