Increasing the Productive Potential of an Ultisol using Cover Crops and Organic and Mineral Fertilization

Abstract The occupation of sandy soils in Brazil has occurred with poor adoption of management technology, which has caused its degradation. The recovery of organic matter, particularly when growing annual plants and cover crops, with mulch residue allows the maintenance of the productive potential of these soils. Thus, the shoot dry mass production (SDMP) of winter cover crops was evaluated in an Ultisol under no-tillage system and in rotation with soybean and maize using 0, 2, 4 and 8 t ha-1 year-1 of poultry litter, mineral fertilizer exclusively and 2 t ha-1 year-1 of poultry litter associated with a half-dose of mineral fertilizer. The experimental design included randomized blocks with four replicates. The use of poultry litter increased the SDMP of the cover crops; the production was relatively high when high doses of poultry litter were applied; on the other hand, the yield of SDMP and grain was limited by the exclusive use of mineral fertilizer. Organic matter and nutrient status improvement by cover crops were one of the reasons for the increase in soybean and maize grain yields.

Biomass of elephant grass and leucaena for bioenergy production / Biomassa de capim elefante e leucena para produção de bioenergia

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)

Biomass of elephant grass and leucaena for bioenergy production / Biomassa de capim elefante e leucena para produção de bioenergia

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...

Microclimate without shade and silvopastoral system during summer and winter / Microclima no sistema sem sombra e silvipastoril no verão e no inverno

This study evaluated the microclimate in a system without shade (WS) and in a silvopastoral system (SP) with eucalyptus during summer and winter, by measuring the air temperature (Ta), black globe temperature (Tg), relative humidity (RH), wind speed (Ws), every 2 hours for 24 hours between rows, shade (SP) and no shade effect (WS). It was employed the randomized blocks design (months), in the plots (systems), subplots (hours) and sub-subplots (seasons). Except for Ta and RH, the Tg (24.73, 26.41ºC), Ws (3.16, 4.57 m s-1), Black globe-humidity index (BGHI) (71.83, 73.84), Thermal load index (TLI) (74.53, 76.11) and Radiant thermal load (RTL) (526.46, 595.80 W m-2), respectively for SP and WS, were higher in WS. Ta, RH and Ws had a quadratic effect of hour. There was an effect of season, respectively in summer and winter, on the Ta (27.55, 14.93°C), RH (72.11, 60.68%), Tg (29.80, 21.33°C), BGHI (80.04, 65.63), TLI (81.64, 69.00) and RTL (575.65, 546.61 W m-2). Tg, RH and RTL showed an interaction of season x hour, and a quadratic effect, and the RTL had an interaction of system x season. The Tg was correlated with BGHI (0.962), TLI (0.956) and RTL (0.809). The silvopastoral system decreased the Tg and Ws, and made the environment more harmonious by decreasing the climatic differences between seasons.

Avaliou-se o microclima em sistema sem sombra (SS) e silvipastoril (SP) com eucalipto no verão e inverno, medindo-se as variáveis temperatura do ar (Ta), globo negro (Tg), umidade relativa (UR), velocidade dovento (Vv) a cada 2 por 24h (entre renques, sombra (SP) e sem efeito de sombra (SS)). O delineamento foi em blocos casualizados (mês), na parcela (sistema), na subparcela (horas) e na sub-subparcela (estação). Com exceção da Ta e UR, a Tg (24,73 e 26,41ºC), Vv (3,16 e 4,57 m s-1), ITGU (71,83 e 73,84), ICC (74,53 e 76,11) e CTR(526,46 e 595,80 W m-2), respectivamente, para SP e SS, foram maiores no SS. A Ta, UR e Vv sofreram efeito quadrático do horário. Verificou-se efeito da estação, respectivamente, no verão e inverno a Ta (27,55; 14,93oC),UR (72,11; 60,68%), Tg (29,80; 21,33oC), ITGU (80,04; 65,63), ICC (81,64; 69,00) e CTR (575,65; 546,61 Wm-2). A Tg, UR e CTR sofreram interação da hora x estação, e efeito quadrático, a CTR interação com sistema x estação. A Tg correlacionou-se com ITGU (0,962), ICC (0,956) e CTR (0,809). O sistema silvipastoril reduziu Tg e Vv e tornou o ambiente mais harmônico diminuindo as diferenças climáticas entre as estações.

Microclimate without shade and silvopastoral system during summer and winter / Microclima no sistema sem sombra e silvipastoril no verão e no inverno

This study evaluated the microclimate in a system without shade (WS) and in a silvopastoral system (SP) with eucalyptus during summer and winter, by measuring the air temperature (Ta), black globe temperature (Tg), relative humidity (RH), wind speed (Ws), every 2 hours for 24 hours between rows, shade (SP) and no shade effect (WS). It was employed the randomized blocks design (months), in the plots (systems), subplots (hours) and sub-subplots (seasons). Except for Ta and RH, the Tg (24.73, 26.41ºC), Ws (3.16, 4.57 m s-1), Black globe-humidity index (BGHI) (71.83, 73.84), Thermal load index (TLI) (74.53, 76.11) and Radiant thermal load (RTL) (526.46, 595.80 W m-2), respectively for SP and WS, were higher in WS. Ta, RH and Ws had a quadratic effect of hour. There was an effect of season, respectively in summer and winter, on the Ta (27.55, 14.93°C), RH (72.11, 60.68%), Tg (29.80, 21.33°C), BGHI (80.04, 65.63), TLI (81.64, 69.00) and RTL (575.65, 546.61 W m-2). Tg, RH and RTL showed an interaction of season x hour, and a quadratic effect, and the RTL had an interaction of system x season. The Tg was correlated with BGHI (0.962), TLI (0.956) and RTL (0.809). The silvopastoral system decreased the Tg and Ws, and made the environment more harmonious by decreasing the climatic differences between seasons.(AU)

Avaliou-se o microclima em sistema sem sombra (SS) e silvipastoril (SP) com eucalipto no verão e inverno, medindo-se as variáveis temperatura do ar (Ta), globo negro (Tg), umidade relativa (UR), velocidade dovento (Vv) a cada 2 por 24h (entre renques, sombra (SP) e sem efeito de sombra (SS)). O delineamento foi em blocos casualizados (mês), na parcela (sistema), na subparcela (horas) e na sub-subparcela (estação). Com exceção da Ta e UR, a Tg (24,73 e 26,41ºC), Vv (3,16 e 4,57 m s-1), ITGU (71,83 e 73,84), ICC (74,53 e 76,11) e CTR(526,46 e 595,80 W m-2), respectivamente, para SP e SS, foram maiores no SS. A Ta, UR e Vv sofreram efeito quadrático do horário. Verificou-se efeito da estação, respectivamente, no verão e inverno a Ta (27,55; 14,93oC),UR (72,11; 60,68%), Tg (29,80; 21,33oC), ITGU (80,04; 65,63), ICC (81,64; 69,00) e CTR (575,65; 546,61 Wm-2). A Tg, UR e CTR sofreram interação da hora x estação, e efeito quadrático, a CTR interação com sistema x estação. A Tg correlacionou-se com ITGU (0,962), ICC (0,956) e CTR (0,809). O sistema silvipastoril reduziu Tg e Vv e tornou o ambiente mais harmônico diminuindo as diferenças climáticas entre as estações.(AU)