41 research outputs found
Avaliação do sistema radicular e de rizomas de um campo natural diferido em Bagé, RS.
A utilização do Campo Sulino natural na pecuária de forma cada vez mais intensa e constante tem provocado a diminuição da sua condição produtiva. A excessiva remoção da parte aérea afeta o desenvolvimento das raízes. Um sistema radicular bem desenvolvido permite às plantas forrageiras explorar maior volume de solo, melhorando a absorção de água e nutrientes. As raízes também funcionam como órgão de reserva, assegurando rápida rebrota e produtividade das plantas forrageiras. O diferimento é uma prática de manejo de pastagens que pode ajudar a recuperar o campo por meio de descanso programado durante um tempo determinado. Este trabalho avaliou o efeito do tratamento de diferimento sobre o sistema radicular de campo natural após três anos de aplicação (agosto de 2000 a julho de 2003) na Embrapa Pecuária Sul (Bagé, RS). As avaliações foram realizadas no campo com presença animal durante todo o ano e sob diferimento de verão/outono (sem animais na área de março a junho). Foram coletadas 18 amostras de solo em cada tratamento, nas profundidades de 0?10 cm e 10?20 cm. As raízes e os rizomas foram separados do solo e entre si, secos e pesados. Houve diferença (p<0,05) para a porcentagem de raízes e a massa da matéria seca de rizomas. A testemunha apresentou 83,98% das raízes na camada de 0?10 cm e o diferimento, 77,5%. Na camada de 10?20 cm, sob diferimento houve aumento de 35% de raízes em relação à testemunha. A maior massa de matéria seca de rizomas foi obtida em pastagem sob diferimento, com 106% a mais em comparação à testemunha. Os resultados indicam vantagem do descanso da pastagem dos Campos Sulinos, tanto no acúmulo de reservas (maior quantidade de rizomas) voltado à propagação de gramíneas rizomatosas de interesse, quanto também no desenvolvimento de raízes na camada de 10?20 cm.bitstream/item/31700/1/BPD-10.pd
Relationship between Amazon biomass burning aerosols and rainfall over the La Plata Basin
High aerosol loads are discharged into the atmosphere\ud
by biomass burning in the Amazon and central\ud
Brazil during the dry season. These particles can interact with\ud
clouds as cloud condensation nuclei (CCN) changing cloud\ud
microphysics and radiative properties and, thereby, affecting\ud
the radiative budget of the region. Furthermore, the biomass\ud
burning aerosols can be transported by the low-level jet (LLJ)\ud
to the La Plata Basin, where many mesoscale convective\ud
systems (MCS) are observed during spring and summer.\ud
This work proposes to investigate whether the aerosols from\ud
biomass burning may affect the MCS in terms of rainfall over\ud
the La Plata Basin during spring. Aerosol effects are very difficult\ud
to isolate because convective clouds are very sensitive\ud
to small environment disturbances; for that reason, detailed\ud
analyses using different techniques are used. The binplot,\ud
2-D histograms and combined empirical orthogonal function\ud
(EOF) methods are used to identify certain environmental\ud
conditions with the possible effects of aerosol loading. Reanalysis\ud
2, TRMM-3B42 and AERONET data are used from\ud
1999 up to 2012 during September–December. The results\ud
show that there are two patterns associated with rainfall–\ud
aerosol interaction in the La Plata Basin: one in which the\ud
dynamic conditions are more important than aerosols to generation\ud
of rain; and a second one where the aerosol particles\ud
have a more important role in rain formation, acting mainly\ud
to suppress rainfall over the La Plata Basin. However, these\ud
results need further investigation to strengthen conclusions,\ud
especially because there are limitations and uncertainties in\ud
the methodology and data set usedCAPESFAPESP - 2012/08115-
A Mixed-Integer convex formulation for production optimization of gas-lifted oil fields with routing and pressure constraints
Topical treatment with a transient receptor potential ankyrin 1 (TRPA1) antagonist reduced nociception and inflammation in a thermal lesion model in rats
The Brazilian Developments On The Regional Atmospheric Modeling System (brams 5.2): An Integrated Environmental Model Tuned For Tropical Areas
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)We present a new version of the Brazilian developments on the Regional Atmospheric Modeling System (BRAMS), in which different previous versions for weather, chemistry, and carbon cycle were unified in a single integrated modeling system software. This new version also has a new set of state-of-the-art physical parameterizations and greater computational parallel and memory usage efficiency. The description of the main model features includes several examples illustrating the quality of the transport scheme for scalars, radiative fluxes on surface, and model simulation of rainfall systems over South America at different spatial resolutions using a scale aware convective parameterization. Additionally, the simulation of the diurnal cycle of the convection and carbon dioxide concentration over the Amazon Basin, as well as carbon dioxide fluxes from biogenic processes over a large portion of South America, are shown. Atmospheric chemistry examples show the model performance in simulating near-surface carbon monoxide and ozone in the Amazon Basin and the megacity of Rio de Janeiro. For tracer transport and dispersion, the model capabilities to simulate the volcanic ash 3-D redistribution associated with the eruption of a Chilean volcano are demonstrated. The gain of computational efficiency is described in some detail. BRAMS has been applied for research and operational forecasting mainly in South America. Model results from the operational weather forecast of BRAMS on 5km grid spacing in the Center for Weather Forecasting and Climate Studies, INPE/Brazil, since 2013 are used to quantify the model skill of near-surface variables and rainfall. The scores show the reliability of BRAMS for the tropical and subtropical areas of South America. Requirements for keeping this modeling system competitive regarding both its functionalities and skills are discussed. Finally, we highlight the relevant contribution of this work to building a South American community of model developers. © Author(s) 2017.1011892222014/01563-1, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2014/01564-8, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo2015/10206-0, FAPESP, Fundação de Amparo à Pesquisa do Estado de São Paulo306340/2011-9, Conselho Nacional de Desenvolvimento Científico e TecnológicoFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq