3,277 research outputs found
Efeito de procedências de Eucalyptus camaldulensis sobre os teores de nutrientes e de carbono orgânico do solo no cerrado.
RESUMO: O objetivo deste trabalho foi avaliar o efeito do plantio de eucalipto nos teores de nutrientes e de carbono orgânico do solo em comparação com uma área virgem de Cerrado. Foram coletadas e analisadas amostras de solo até 1 m de profundidade em um experimento de procedências de Eucalyptus camaldulensis e em uma área adjacente de Cerrado, na mesma posição topográfica, em Planaltina, Distrito Federal. O solo é Latossolo Vermelho, argiloso (55% de argila, 23% de silte, 2% de areia grossa e 20% de areia fina) e distrófico. Na ocasião do plantio, o eucalipto foi adubado com 40 g de sulfato de amônio, 60 g de superfosfato triplo, 20% decloreto de potássio, 2 g de sulfato de zinco, 3 g de bórax e 500 g de calcário dolomítico por cova. As procedências avaliadas foram: 10911 de Emu Creek, Queensland; 9856 de Agnew Road, West Australian; e 10557 de Kimberley Area, West Australian. O pH teve crescimento linear com o aumento da profundidade, porém, nas áreas reflorestadas com a procedência 9856, esse aumento foi proporcionalmente maior que o observado para as áreas com as outras procedências. O teor de magnésio foi menor na área com Cerrado nativo em comparação com as reflorestadas com as procedências 9856 e 10911. O plantio de eucalipto, comparado com o Cerrado, elevou os teores de potássio e de carbono orgânico, sobretudo, nas camadas superficiais do solo. Os teores de fósforo, de potássio, de cálcio, de magnésio e de carbono orgânico no solo diminuíram com o aumento da profundidade, tanto nas áreas reflorestadas como em áreas de Cerrado. ABSTRACT: The objective of this paper was to evaluate the effect of Eucalyptus camaldulensis plantation on soil carbon and nutrients contents in comparasion to virgin area of Cerrado. Soil samples of soil were collected down to 1 m depth in the soil profile in an experiment composed by three Eucalyptus camaldulensis provenances and an adjacent area of Cerrado. Soil was classified as dystrophic Claying Red Latossol composed by 52% of clay, 13% of silt, 3% of coarse sand and 25% of fine sand. At seedling time fertilizers were applied at the rate: 40 g of ammonium, 60 g of triple superphosphate, 20 g of potassium chloride, 2 g zinc sulphate, 3 g of borax and 500 g dolomitic lime for plant per planting pit. Provenances from Emu Creek, Queensland (10911); Agnew Road, West Australian, (9856) and Kimberley Area, West Australian (10557) were evaluated. The pH increased linearly as depth increased, however for provenace 9856 this increase was proportionally higher than the others. The magnesium content was lower in Cerrado than in reforested areas with provenances 9856 and 10911. Eucalypt plantation, compared with the Cerrado vegetation, increased organic carbon and potassium contents in the upper soil layers. Soil phosphorus, potassium, calcium, magnesium and organic carbon contents decreased as depth increased in both reforested ares and in the Cerrado.bitstream/CPAC-2009/26774/1/bolpd_142.pd
Contribuição à identificação anatômica de 50 espécies madeireiras comercializadas no Estado do Pará.
Negative Even Grade mKdV Hierarchy and its Soliton Solutions
In this paper we provide an algebraic construction for the negative even mKdV
hierarchy which gives rise to time evolutions associated to even graded Lie
algebraic structure. We propose a modification of the dressing method, in order
to incorporate a non-trivial vacuum configuration and construct a deformed
vertex operator for , that enable us to obtain explicit and
systematic solutions for the whole negative even grade equations
Estudo químico e micrográfico de madeiras da Amazônia.
bitstream/item/57843/1/CPATU-ComTec19.pd
Strategic environmental assessment in Tróia (Portugal)
Proceedings of the First International Conference on Coastal Conservation and Management in the Atlantic and Mediterranean, p. 91-98Over the last two decades, the Tróia peninsula (SW coast of Portugal) has been designated by the Portuguese authorities both as a protected area and as an area of tourism development. The private investor that took over the tourism developments in Tróia asked the Institute of Marine Research (IMAR) to undertake an SEA, to help frame
the design and management of the future resort. SEA results were changed by local/central government decisions,
granting “more” than stakeholder/owner’s proposal, in terms of loads and densities. This process, as well as the main
characteristics and results of the SEA, are presented and discussed
Efeito da frequência de preparo periódico nos indicadores da compactação do solo.
O uso contínuo de máquinas nas operações de preparo do solo para o plantio resulta em significativas alterações nos seus atributos físicos, dentre as quais, destacam-se a compactação, um dos principais problemas enfrentados pelos agricultores em diversas regiões do Brasil. O objetivo deste trabalho foi avaliar o efeito de operações sucessivas de aração e gradagem sobre os indicadores de compactação do solo. Para tanto, aplicou-se, em um Latossolo Amarelo Distrocoeso argissólico, sob pastagem natural, cinco níveis de distúrbios, resultantes de eventos mensais de aração e gradagem, sendo: T0 (Controle); T1 (2 eventos); T2 (4 eventos); T3 (6 eventos); T4 (8 eventos). Verificou-se que a frequência das operações de aração e gradagem reduziu o diâmetro médio de agregados, a macroporosidade e a condutividade hidráulica do solo saturado, aumentando a densidade do solo e a resistência à penetração
Variação anatômica dos elementos estruturais da madeira de copaifera reticulata (Leguminosae-Caesalpinioideae) no sentido alburno-medula.
Co-infecção pelo vírus dengue 3 e 4 em pacientes da Amazônia brasileira
The natural co-infection with dengue virus can occur in highly endemic areas where different serotypes have been observed for many years. We report here four cases of DENV-3/DENV-4 co-infection detected by serological and molecular tests among 674 patients with acute undifferentiated fever from the tropical medicine reference center of Manaus City, Brazil, between 2005 and 2010. Analysis of the sequences obtained indicated the presence of genotype 3 and 1 for DENV-3 and DENV-4 respectively.A co-infecção natural com os vírus dengue pode ocorre em áreas altamente endêmicas onde diferentes sorotipos têm sido transmitidos por muitos anos. Relatamos aqui quatro casos de co-infecção com DENV-3/DENV-4 detectados por testes sorológicos e moleculares entre 674 pacientes com febre indiferenciada aguda, atendidos em um centro de medicina tropical de referência da cidade de Manaus, Brasil, entre 2005 e 2010. As análises das sequências obtidas indicaram a presença dos genotipos 3 e 1 para DENV-3 e DENV-4 respectivamente
Toxicity to cotton boll weevil Anthonomus grandis of a trypsin inhibitor from chickpea seeds.
Evaluation of the supramolecular interaction of Congo red with cucurbiturils using mass spectrometry and spectroscopic methods
The ability of cucurbit[n]urils (CB[n]) to decolourise aqueous solutions of the azo dye Congo red (CR) was described more than a century ago alongside the first synthesis of CB[n]. No subsequent studies of the nature of the physical interactions have been reported despite the interest in using CB[n] as adsorbents for the removal of CR and related organic dyes from wastewaters. In the present work the supramolecular interaction between CB[n] (n = 7, 8) and CR was studied by electrospray ionisation mass spectrometry (ESI-MS), 1H NMR, and solid-state characterisation of isolated complexes. Under positive ESI, the formation of host–guest complexes in the gas phase was not observed, suggesting that CR anions do not interact with the portals and the nonpolar inner cavity of the CB[n] molecules. Conversely, under negative ESI, 1 : 1 and higher order (1 : 2, 2 : 1, 3 : 1 and 2 : 2) CR: CB[7] and CR: CB[8] adducts were detected, which is attributed to interaction between CR and the outer surface hydrogens of CB[n]. Solid-state supramolecular adducts between CB[n] and CR were isolated from aqueous media under either ambient conditions, giving structures denoted as CR@CB[n](RT), or hydrothermal (100 ºC) conditions, giving structures denoted as CR@CB[n](100). The adducts were characterised by elemental and thermogravimetric analyses (TGA), powder X-ray diffraction (PXRD), and spectroscopic methods (FT-IR, FT-Raman, 13C{1H} CP MAS NMR, UV/vis and near-IR absorption, fluorescence excitation and emission). The interaction conditions and acid content of the starting CB[n] influenced the protonation state of CR molecules. CR@CB[7](RT) contained only unprotonated CR, while CR@CB[8](100) contained exclusively protonated CR (ammonium and azonium/quinoid structures). Other adducts contained mixtures of protonated/unprotonated forms.publishe
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