947 resultados para Litter (Trash)


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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The soil is one of the main C pools in terrestrial ecosystem, capable of storing significant C amounts. Therefore, understanding the factors that contribute to the loss of CO2 from agricultural soils is critical to determine strategies reducing emissions of this gas and help mitigate the greenhouse effect. The purpose of this study was to investigate the effect of soil tillage and sugarcane trash on CO2 emissions, temperature and soil moisture during sugarcane (re)planting, over a study period of 15 days. The following managements were evaluated: no-tillage with crop residues left on the soil surface (NTR); without tillage and without residue (NTNR) and tillage with no residue (TNR). The average soil CO2 emission (FCO2) was lowest in NTR (2.16 µmol m-2 s-1), compared to the managements NTNR (2.90 µmol m-2 s-1) and TNR (3.22 µmol m-2 s-1), indicating that the higher moisture and lower soil temperature variations observed in NTR were responsible for this decrease. During the study period, the lowest daily average FCO2 was recorded in NTR (1.28 µmol m-2 s-1), and the highest in TNR (6.08 µmol m-2 s-1), after rainfall. A loss of soil CO2 was lowest from the management NTR (367 kg ha-1 of CO2-C) and differing significantly (p<0.05) from the managements NTNR (502 kg ha-1 of CO2-C) and TNR (535 kg ha-1 of CO2-C). Soil moisture was the variable that differed most managements and was positively correlated (r = 0.55, p<0.05) with the temporal variations of CO2 emission from NTR and TNR. In addition, the soil temperature differed (p<0.05) only in management NTR (24 °C) compared to NTNR (26 °C) and TNR (26.5 °C), suggesting that under the conditions of this study, sugarcane trash left on the surface induced an average rise in the of soil temperature of 2 ºC.

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The aim of this study was to analyze the effect of flushing on the reproductive performance of Morada Nova (MN) and Santa Inês (SI) ewes submitted to fixed time artificial insemination (TAI). Twenty seven SI and 24 MN supplemented with concentrate (1% of live weight, on average), for 75 days during the breeding season. After 30 days of supplementation, ewes were synchronized with the aid of a hormonal protocol (HP) based on progesterone, eCG and cloprostenol. The estrus observation was conducted at 12, 24, 36 and 48 h after the end of HP with the aid of two ruffians. TAI was done 55 h after the end of HP. From 20 to 45 days after the beginning of the HP ewes were exposed to rams (natural breeding). The pregnancy diagnosis was evaluated 70 days after TAI. We analyzed the weight, body condition score, estrus rate, pregnancy rate and prolificacy testing the effects of race, week of supplementation and body condition score class. The weight and body conditions of ewes varied according to the week of supplementation, with higher values in the first two weeks following TAI. The estrus rate was 88.2% and 43.2% of the ewes showed estrus up to 24 hours of the end of the HP. The pregnancy rate per TAI was 31.3% and the pregnancy rate after natural breeding was 50.0%. It was observed that body condition score classes interfered in pregnancy rates. There was a higher percentage of multiple births by pregnancy by TAI than by natural breeding. It was concluded that the flushing resulted in weight gain and better body conditions ensuring the standardization of the herd for breeding season, which therefore improved reproductive performance. The HP used advanced the onset of estrus and increased prolificacy, but was inefficient in the synchronization of woolless sheep.

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The organic fertilizer can be a viable alternative in the production of forage grasses, however there is little information regarding doses and composition of the major organic fertilizers. The aim of this paper was to verify the influence of the different doses of organic compost produced from two types of poultry litter on the structural, morphogenetic and productive characteristics of Brachiaria brizantha cv 'Piatã'. The experiment was conducted in a greenhouse in a completely randomized design in a factorial scheme l with parcel subdivided in time. The parcels were composed by six treatments: two types of compost (poultry litter based in sugar cane and napier grass) in three doses (100, 200 and 300kg ha-1 equivalent N.) and the subparcels by the four different periods of cut. The composts were applied in a unique dose, after the uniformization cut, at the quantities: 11,36 and 11,83, 22,73 and 23,67, 34,09 and 35,50 g pot-1 for the poultry litter based in sugar cane and napier grass, respectively which are equivalent to the rates of 0, 100, 200 and 300kg ha-1 of N. The variables measured were: dry matter production (DMP), leaf appearance rate (LApR), phyllochron, leaf elongation dose (LER) and shoots elongation rate (SER), number of green leaves (NGL), final size of the leaf (FSL). No significant difference between the types of composts and in the interaction compost x doses was observed, thus, both could be used without the risk of loss in the use of the nutrients by the plants evaluated in the experiment. There was a significant difference between the DMP, LApR, phyllochron, LER, SER, NGL and FSL because of the increasing rates of nitrogen, followed by a linear model of prediction. The effect of the periods of slaughter was also observed, where the slaughters carried out in the summer presented a better performance over the morphogenetic and structural features evaluated.

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The objective of this study was to evaluate the straw decomposition of the Urochloa and Panicum after intercropped with corn and nitrogen fertilization, as well as, the agronomic performance of soybean in succession. The experiment was conducted in an Oxisol in Cerrado conditions under no-tillage eight years ago. After the corn harvest intercropped with grass and cutting of forage homogenization were applied N rates (0, 50, 100 and 200 kg ha-1 of N - urea source) in coverage. The plots consisted of Urochloa brizantha,Urochloa ruziziensis and Panicum maximum Tanzânia and Mombaça sown at the time of corn sowing and subplots composed by accumulated amounts of nitrogen applied in forage plants prior to the soybean cultivation (0, 250, 500 and 1000 kg ha-1 of N, after five cuts). The experimental design was a randomized block with four replications in a split plot. Soon after the last cut of the forage, proportionate amount of fresh mass of the species of each subplot was wrapped in nylon bags called Litter Bags, these being deposited in direct contact with the soil, to determine the time of decomposition of the dry mass during a period of 150 days. The nitrogen doses, as well as, the corn intercropped with forages (except with Mombaça) interfere similarly in the straw decomposition of forage and in the soybean yield in succession. All the consortiums of corn and nitrogen fertilization predecessors determined that, at 60 days after desiccation and cutting, still remained between 50 and 60% of the initial straw for no-tillage system.

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Poultry facilities must provide an environment that ensures thermal comfort allowing the animal to express its genetic potential for production; and new tools are being applied to measure the thermal comfort, especially thermal cameras. The objective of this study was to evaluate the association of the surface temperature of the birds with those from the facilities, and estimate the sensible heat transfer. For this, the thermal conditions of rearing in two aviaries with different ventilation systems, during the period of March to April 2011 were recorded. The aviaries were divided into six quadrants for the registration of surface temperatures obtained using an infrared thermal camera. In each quadrant the ambient temperature, relative humidity and wind velocity during the obtention of images were also recorded. It was observed that the surface temperatures of birds are associated with the surface temperature of the rearing facilities (side curtains, roof and litter). In aviary with negative pressure higher wind speeds compared to the conventional one were recorded and; therefore, allowed a higher sensible heat transfer by birds, suggesting that this provided better conditions for thermal comfort.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The presence of trash from the mechanical harvest of green cane on sugarcane plantations promotes changes in the agricultural management, for example, in the mechanical cultural practices of ratoon cane in-between the rows and nitrogen (N) fertilization. The goal of this study was to evaluate the performance of sugarcane in different harvest systems, associated to the mechanical cultural practices in interrows and N rates. The study was carried out on a sugarcane plantation in Sales Oliveira, São Paulo, Brazil, with the sugarcane variety SP81-3250, on soil classified as Acrudox, in a randomized block design with split-split plots and four replications. The main treatments consisted of harvest systems (harvesting green cane or burnt cane), the secondary treatment consisted of the mechanical cultural practices in the interrows and the tertiary treatments were N rates (0, 30, 60, 90, 120 and 160 kg ha-1), using ammonium nitrate (33 % N) as N source. The harvest systems did not differ in sugarcane yield (tons of cane per hectare - TCH), but in burnt cane, the pol percent and total sugar recovery (TSR) were higher. This could be explained by the higher quantity of plant impurities in the harvested raw material in the system without burning, which reduces the processing quality. Mechanical cultural practices in the interrows after harvest had no effect on cane yield and sugar quality, indicating that this operation can be omitted in areas with mechanical harvesting. The application of N fertilizer at rates of 88 and 144 kg ha-1 N, respectively, increased stalk height and TCH quadratically to the highest values for these variables. For the sugar yield per hectare (in pol %), N fertilization induced a linear increase.