1,316 research outputs found

    Central Algarve tufa platforms, Southern Portugal. Geomorphological characterization and genesis.

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    Modern and fossil carbonate tufa outcrops exist in the Algarve (S Portugal), where climate is Mediterranean and all modern incrusting springs are intermittent and fed by Jurassic aquifers. The major Pleistocene tufa on the Algibre flexure southern slopes are in the Cadouço, São Lourenço and Rio Seco streams basins. There were identified fluvial barrier tufas and low energy fluvial tufas. The Algarve has three main geomorphological domains: the Paleozoic flysch mountains, the Meso-cenozoic karst hills and the littoral Plio-Pleistocene detrital platform.Located in the Eurasian-Nubian plates boundary, the whole system have been deformed by distensive and compressive tectonics, which give rise to a complex groundwater system. Neotectonical activity has been reported in many works. Feio (1952) identified Pliocene and Quaternary marine platforms up to 160 m a.s.l., but also mature levels at 200 m along with other plain surfaces. The largest tufa platforms lie in unconformity with the currentdrainage system, where outcrops are dominated by low gradient facies, v. g. detrital bedded lime muds. Machados platform is dominated by bryophytes and other rapid flow facies, and cemented riverbed upstream. These outcrops lie down on larger areas in Loulé and Lagos e Relva, at altitudes between 160-200 and 120-150 respectively. Environmentally conformal tufas occupy some sectors of the modern Cadouço, Rio Seco and São Lourenço streams. Modern tufa range from spring dominated mounds in Lagos eRelva and barrier and low gradient fluvial dominated tufas (v. g. São Lourenço and Loulé). The ocean proximity enables the formation of eustatic platforms, which provided substratum for tufa accumulations. Vertical movements, including salt tectonics, and lowstands promoted fluvial incision and later tufa developments in modern streams. Acknowledgments: Financed by the Fundação para a Ciência e Tecnologia PhD grant SFRH/BD/62323/2009

    Optimal space-time coverage and exploration costs in groundwater monitoring networks

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    A method to determine the optimal subset of stations from a reference level groundwater monitoring network is proposed. The method considers the redundancy of data from historical time series, the times associated with the total distance required to run through the entire monitoring network, and the sum of the times for each monitoring station. The method was applied to a hypothetical case-study consisting of a monitoring network with 32 stations. Cost-benefit analysis was performed to determine the number of stations to include in the new design versus loss of information. This optimisation problem was solved with simulated annealing. Results showed that the relative reduction in exploration costs more than compensates for the relative loss in data representativeness.info:eu-repo/semantics/publishedVersio

    Optimal Space-time Coverage and Exploration Costs in Groundwater Monitoring Networks

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    A method to determine the optimal subset of stations from a reference level groundwater monitoring network is proposed. The method considers the redundancy of data from historical time series, the times associated with the total distance required to run through the entire monitoring network, and the sum of the times for each monitoring station. The method was applied to a hypothetical case-study consisting of a monitoring network with 32 stations. Cost-benefit analysis was performed to determine the number of stations to include in the new design versus loss of information. This optimisation problem was solved with simulated annealing. Results showed that the relative reduction in exploration costs more than compensates for the relative loss in data representativeness

    The use of chestnuts (Castanea sativa Mill.) as a source of resistant starch in the diet of the weaned piglet

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    tTwenty-four piglets, with a mean weight of 6.11 kg, were allocated to three experimentaldiets (8 piglets per diet). The starch content of the experimental diets was 39% consistingeither of 100% wheat starch (CD), 50% wheat starch and 50% chestnut starch (CN50) or 100%chestnut starch (CN100). The piglets received these diets for 35 days. Total tract apparentdigestibility (TTAD) was measured when piglets were aged 32–39 days and 46–53 days.Afterwards, the animals were sacrificed, their gastrointestinal compartments weighed, andthe contents of their caecum and colon collected. Diet did not influence the feed intakeor growth rate of the piglets, but had a significant effect on their feed conversion ratiowhich was 1.27, 1.30 and 1.37 for diets CD, CN50 and CN100, respectively (P=0.042). Pigletsreceiving the CN50 diet exhibited lower faecal scores compared to CD and CN100 groups( 2= 39.31, P<0.001). There was a trend (P=0.067) towards an increase in the TTAD of drymatter (DM) in the two chestnut-containing diets, but only when piglets were younger(32–39 days). The TTAD of crude protein (CP) was decreased (P<0.001) in CN100 group rel-ative to CD and CN50 groups, independently of age. Relative to the CD group, the coefficientof TTAD of NDF was increased by 0.18 units in the CN50 group and 0.25 units in the CN100group, when the piglets were aged 32–39 days. These differences were reduced to 0.09 and0.17 units, respectively, when the piglets were aged 46–53 days. There were tendencies(P<0.10) towards increases in the full and empty weights of the large intestine in CN100group. Moreover, diet had no significant effect on villus height and width. In the jejunum,crypt depth was reduced in CN100 group (P=0.006), while the villus height:crypt depth ratiowas increased with the CN50 and CN100 diets (P=0.018). Diet had no significant effect onDM and pH of the caecal or colonic contents. In the caecum, the concentration (mmol l−1) ofpropionic acid was 5.15, 9.43 and 14.7 (P=0.042) for diets CD, CN50 and CN100, respectively.The concentration (mmol l−1) of butyric acid was 3.50, 4.90 and 9.84 (P=0.025). Conversely,diet had no significant effect on the concentration of short chain fatty acids in the colon.In conclusion, chestnuts could be used as an alternative source of RS in the diet of weanedpiglets, although their feed conversion ratio (FCR) may be worsene

    e-Sispaf: Sistema de Informação e Promoção de Produtos e Serviços da Agricultura Familiar - guia de instalação e configuração do sistema. Versão 0,1.

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    O e-Sispaf é um sistema de informação que promove a consolidação e a disseminação de conhecimentos relativos ao mapeamento da produção e informações da comercialização e do mercado de produtos convencionais, orgânicos e artesanais para agricultura familiar. O objetivo do sistema é facilitar as transações entre produtores e consumidores, promovendo, assim a execução de ações efetivas para o crescimento da renda do segmento. Através do sistema, produtor e consumidor podem trocar informações e negociar suas produções diretamente, sem nenhum intermediário. O sistema é importante porque auxilia na tomada de decisões de todos os seus possíveis usuários (produtores, comerciantes e governos), que passam a contar com instrumentos decisivos para o planejamento das políticas agrícolas. O e-Sispaf foi Implementado utilizando-se software livre (osCommerce) para o ambiente web, eliminando assim custos para operacionalização. Baseia-se nos pressupostos do comércio eletrônico (e-commerce) e oferece aos usuários - que podem ser produtores rurais, cooperativas, associações ou organizações públicas ou privadas - a oportunidade de expor seus produtos e trocar dados, obtidos junto aos produtores, às cooperativas, às associações, aos órgãos do governo e/ou órgãos privados localizados na região de abrangência do e-Sispaf. Este guia contém um conjunto de informações, distribuídas em sessões, com o objetivo de facilitar a instalação e configuração do e-Sispaf. Algumas das opções de configuração disponibilizadas não foram utilizadas na atual versão do e-Sispaf. Elas fazem parte do software osCommerce e são configuradas para aquisição de produtos de forma on-line, o que não ocorre no e-Sispaf.bitstream/item/17881/1/docmeionorte191.pd

    THE RELATIONSHIPS BETWEEN SPRINT RUN AND STRENGTH PARAMETERS IN YOUNG ATHLETES AND NON-ATHLETES

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    The aim of this study was to examine the relationships between the sprint run and strength tests, which measure the capability to produce force in isometric, pure concentric and stretch shortening cycle muscular actions. The seventy two subjects were assessed for six tests 60m sprint run, to evaluate the speed, and isometric leg-press, squat jump, countermovement jump, drop jump, and 5 horizontal jumps, to evaluate strength parameters. The 5 jumps, was the most important predictor of the 60m sprint time, maybe because of is cyclic and horizontal characteristics (more similar to the specific movement of sprint run). We suppose that the reason for results do not explain different relationship between tests and sprint performance, in young athletes can be find in multifactorial characteristics of sprinting performance and the characteristics of the subjects, youngest have reduced training adaptation

    FLUVIAL LIMESTONE TUFFS FROM THE S. PORTUGAL (LOULE-TAVIRA) AND N. MOROCCO (TETUAN): COMPARISON AND ENVIRONMENTAL IMPLICATIONS

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    Limestone tuff deposits precipitated in fluvial environments are widespread in the northern Morocco and the S Portugal. These deposits represent environmental conditions prone for the carbonate precipitation mainly in areas of Mesozoic limestone substratum with active water seepage from the aquifers. The mesoscopic and microscopic characteristics of tuff deposits from Tetouan (Morocco) and Loule and Tavira (Portugal) are very alike; namely on deposit types (e.g. phytoherm barriers; banded limestones with abundant vegetation macro-remains; carbonates precipitation as cement of some early alluvial conglomerates or interbedded alluvial deposits). The common textural features and macro-facies (e.g. banded calcite in regular layers ; moldic porosity; textures resulting from carbonate precipitation mediated by bacteriological activity) point to a similar origin of these limestone tuffs on both sides of Gibraltar Strait despite their slightly different climatic conditions that are influenced by the active inflow of surface Atlantic water towards the Mediterranean (for the Tetouan region) and by the Azores anticyclone (for the Loulé-Tavira region). The field observations show that the limestone tuffs precipitation is nowadays residual and radiocarbon dating of Portuguese deposits points to a chronological framework for their formation starting in the beginning of the post-Younger Dryas climatic recovery and ending around 2.5 ky BP. The oxygen stable isotopes data show a gradual change in the tuffs isotopic signature through the time interval during which the system remained active, without any particular record of climate events such as the 8.2 ka. The available data and those from monitored modern pluvial characteristics allow the speculation on the parameters controlling the limestone tuffs deposition on both northern and southern sides of the Gibraltar Strait during the Holocene. The carbonate deposition on fluvial systems, such as the studied ones, probably depends on the precipitation / evaporation balance leading to the availability and turbulence of the flowing water along the streams. Acknowledgments: This works was done with the financial support of the FCT Proc. 441.00 CNRST- MARROCOS and PTDC/CTE-GIX/117608/2010 projects and the SFRH/BD/62323/2009 grant
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