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 $\hat{sl}(2)$, that enable us to obtain explicit and systematic solutions for the whole negative even grade equations

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

Caracterização do sistema radicular e dos componentes da produtividade em quatro genótipos de milho cultivados sob déficit hídrico.

Nesse trabalho foram combinadas avaliações de parâmetros agronômicos com morfometria de raízes usando o programa WinRhizo, a fim de detectar características no sistema radicular que permitam a manutenção da produtividade em quatro materiais genéticos de milho (BRS1010, 2B710, DKB390 e BRS1055), cultivados em dois níveis de água no solo (CC- capacidade de campo, e DH- déficit hídrico). Plantas oriundas dos genótipos DKB390 e BRS1055 sob DH mantiveram valores de produção de grão similares aos de seus respectivos controles, sob CC. Por sua vez, plantas oriundas dos genótipos 2B710 e BRS1010 apresentaram perdas substanciais na produção de grãos com a imposição do DH. Cabe ressaltar que plantas oriundas do genótipo BRS 1055 apresentaram estratégia abaixo do solo de evitação à seca, por aumentarem a área superficial de raízes finas e muito finas, sendo esse um ponto de divergência em relação ao também tolerante genótipo DKB 390.bitstream/item/122152/1/bol-111.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

Assessment of a Sand Spit Morphodynamics Under Extreme Flood Events

&lt;p&gt;Spits are landforms that present a complex morphology, which depends on currents, waves, sediment transport, tidal range and anthropic-induced changes. Their position and shape is subject to extreme events like flood river discharges and storms. They can also respond to processes that take place at larger time scales, as plate tectonics, sea level rise or even climatological patterns with teleconnections all over the world, as the well know North Atlantic Oscillation (NAO) or El Ni&amp;#241;o-Southern Oscillation (ENSO). This is the case of the Douro river mouth sand spit located on the northern coast of Portugal. This naturally dynamic sand spit, which has moved landwards over the past decades, has caused frequent nuisance to navigation, affecting width and depth of the navigation channel. Therefore, a breakwater was constructed in an attempt to stabilise the sand spit and the estuary inlet.&lt;/p&gt;&lt;p&gt;Validated hydrodynamic numerical models (openTELEMAC-MASCARET and Delft3D) of the Douro river estuary have demonstrated ability to accurately describe the estuarine hydrodynamic patterns and water elevation under extreme flood conditions. Model results showed that for higher river flow discharges the sand spit is partially inundated.&lt;/p&gt;&lt;p&gt;In this work a morphodynamic model (Delft3D) of the estuary was implemented to assess both the morphodynamics of the sand spit under extreme events, including the effect of sea level rise due to climate change, and the variation of extreme water levels along the estuary due to spit erosional processes that can occur during flood events.&lt;/p&gt;&lt;p&gt;Preliminary results show that the sand spit will be locally eroded for the higher river flood discharges, forming a two-secondary-channels system, with one channel located near the breakwater&amp;#8217;s southern extremity and the other, narrower, near the south bank. Associated with these two channels, two depositional bars will be formed in front of the channels at the coastal platform. However, the inner immersed sand spit will be suffering a sedimentation process for all of the simulated scenarios. This way, neither the river mouth discharge conditions nor the water levels inside the estuary will suffer significant changes according to the simulated scenarios.&lt;/p&gt;&lt;p&gt;These results will be complemented with further analyses considering the sediment size influence, tidal level, storm surge, sea level rise and river flood discharges.&lt;/p&gt;&lt;p&gt;Acknowledgements: To the Strategic Funding UIDB/04423/2020 and UIDP/04423/2020 (FCT and ERDF) and to the project EsCo-Ensembles (PTDC/ECI-EGC/30877/2017, NORTE 2020, Portugal 2020, ERDF and FCT). The authors also want to acknowledge the data provided by EDP and IH.&lt;/p&gt;</jats:p

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