69 research outputs found

    Biogeografia de Portugal Continental

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    Apresentam-se alguns conceitos fundamentais usados em Biogeografia. Propõe-se uma tipologia biogeográfica para Portugal continental desenvolvida a partir dos trabalhos de S. Rivas-Martínez para a Península Ibérica, principalmente: RIVAS-MARTÍNEZ et al (1990). São enumeradas as unidades biogeográficas reconhecidas no território continental nacional e discutem-se os seus limites até ao nível de Superdistrito, bem como os critérios e fundamentos florísticos e fitossociológicos usados para a sua segregação. Apresenta-se uma primeira aproximação cartográfica à escala 1 : 2 500 000 das unidades biogeográficas reconhecidas.Biogeography of continental Portugal. Some fundamental concepts of Biogeography are briefly presented. A biogeographical tipology of continental Portugal, following the concepts and previous works of S. Rivas-Martínez for the Iberian Peninsula, is presented - mostly RIVASMARTÍNEZ et al. (1990). The biogeographical units down to the level of superdistrict in the territory are briefly described, as well as the floristic and phytosociological criteria supporting their definition and circunscription. A first cartographical approach is presented in the 1: 2.500.000 scale

    Carta da Vegetação Natural Potencial de Caldas da Rainha

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    A POTENTIAL NATURAL VEGETATION MAP OF CALDAS DA RAINHA . This article presents and discusses a Potential Natural Vegetation (PNV) Map of the Caldas da Rainha Municipality. After outlining the concept, an assessment is made of the conditioning factors that affect the PNV (soil, geology, lithology, bioclimate). A model allowing for the estimation of the PNV is then put forward based on a correspondence drawn between the PNV and the relevant biotopic variables. The resulting PNV map was validated through comparison with the vegetal communities effectively present in the field. The PNV Map of Caldas da Rainha shows that almost the entire area of this Municipality corresponds to potential cork-oak, Portuguese-oak, elm and willow forests. Cork-oak forests are associated with podzolic soils, made up of sand and sandstone; Portuguese-oak forests (Quercus faginea subsp. broteroi) occur in the presence of limestones, clays, and dolomites; whereas willow and elm forests are associated with the floodplains of the hydrographical unit called the Ribeiras do Oeste. Finally, it is worth noting that the most relevant features in terms of protection and conservation (due both to their rarity and to the presence of endemic species) are to be found in complex communities: halophytic (Óbidos lagoon), psammophilous, rupicolous and peat bogs

    Consumer perception of water quality during an off-flavor event in Fortaleza-Brazil.

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    During a taste and odor episode (2-methylisoborneol) in a reservoir that supplies the Fortaleza Metropolitan Region, Brazil, two surveys were conducted to determine tap water usage behavior as well as the sensory sensitivity towards off-flavors of participants with the same level of education. Most volunteers did not consume tap water, mainly due to safety concerns (57%) and disagreeable organoleptics (21%). The majority of those who did use tap water (73%) did so because of economic reasons and the remainder because of the use of point-of-use water filtration systems, which rendered the water safer in their perception. The Human Development Index (HDI), as a measure of income, did not influence the rate of rejection. Volunteers from low and medium HDI neighborhoods were as likely to reject tap water as those from high HDI neighborhoods. Chlorine flavor and earthy flavor were the most perceived off-flavors. Water containing moderate amounts of off-flavor compounds (dilution 1:2 tap/bottled water) was considered ‘acceptable’ by volunteers while water containing low concentrations (dilution 1:5 tap/bottled water) was considered ‘good’

    The effect of water treatment unit processes on cyanobacterial trichome integrity.

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    Many toxic and/or noxious cyanobacteria appear in nature with a filamentous, stacked cell arrangement called trichomes. Although water treatment can be optimized to keep cyanobacterial cells intact and to avoid the release of toxic and/or noxious compounds, many physical and chemical stresses encountered during the treatment process may result in trichome truncation, decreasing treatment efficiency by allowing single cells or short trichomes to reach the product water. This makes it possible for harmful/noxious compounds as well as organic matter to enter the distribution system. Investigations in a pilot and three full-scale water treatment plants were carried out in order to elucidate the degree of trichome truncation across different unit processes. It was found that genera (Pseudanabaena, Planktolyngbya) with short trichomes ( < 10–12 cells per trichome), are hardly affected by the unit processes (loss of one to four cells respectively), while genera (Planktothrix, Geitlerinema, Dolichospermum) with longer trichomes (30+ cells per trichome) suffer from high degrees of truncation (up to 63, 30, and 56 cells per trichome respectively). The presence of a rigid sheath and/or mucilaginous layer appears to offer some protection from truncation. It was observed that certain unit processes alter the sensitivity or resilience of trichomes to disruption by physical stress. Some genera (Planktothrix, Geitlerinema) were sensitive to pre-oxidation, making them more susceptible to shear stress, while Dolichospermum sp. appears more robust after pre-oxidation. While the potential of toxicogenic genera breaking through into the product water is a real danger, in the current study no toxicogenic cyanobacteria were observed. This work stresses the need for plant operators to study the incoming cyanobacterial composition in the raw water in order to adjust treatment parameters and thus limit the potential of toxic/noxious compound breakthrough

    Notas do Herbário Florestal do INIAV (LISFA): Fasc.XXXVI. Síntese do conhecimento taxonómico do género Salix L. em Portugal Continental

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    A chave que de seguida se apresenta tem por base a desenvolvida por DÍAZ GONZÁLEZ & LLAMAS, 1987, com as devidas atualizações taxonómicas e nomenclaturais que entretanto ocorreram, e algumas correções com, posteriores e inevitáveis, adaptações de forma a incluir táxones não analisados nesse trabalho. Da bibliografia consultada procuramos averiguar as descrições originais dos táxones e/ou outras que preconizam descrições bem desenvolvidas e completas dos vários caracteres usados para a determinação deste género. Esta chave foi testada em ca. 370 espécimes recolhidos maioritariamente na parte portuguesa da Bacia do Tejo entre os meses de Abril e Outubro de 2009 a 2011, incluindo sobretudo indivíduos com folhas bem desenvolvidas. Recolhemos ainda para comparação alguns espécimes no Rio Lima (fim do Inverno de 2011), Sado (Outono de 2011) e em França, Bacia do Rio Ain, (fim da Primavera de 2011), assim como alguns espécimes ornamentais em jardins da Área Metropolitana de Lisboa. De seguida apresentamos as opções tomadas para a construção desta chave

    Bioindicators assessing water quality and environmental impacts of water treatment plant sludge.

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    This study had as objectives to assess water quality using macroinvertebrate communities in Gaviao artificial reservoir (Brazil), used to supply potable water to 2.5 million people, and to evaluate how these organisms responded to the discharge of water treatment sludge into a natural wetland. A total of 1,621 specimens across 23 taxa were identified. Mollusca were the dominant and most frequent group while Insecta presented the most richness. Based on feeding mode, there were more predator organisms than scrapers. The Biological Monitoring Working Party (BMWP') method showed to be more sensible to water quality variations than ASPT index, going from polluted to questionable water quality more frequently. The chemical parameters analysed showed no significant variations and were not a sensitive method for assessing water quality. No organisms could be found downstream of the sludge discharge point, indicating a high impact of sludge disposal on local biota

    Notas do Herbário Florestal do INIAV (LISFA): Fasc. XXXVI

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    Análise de dados categóricos de integridade celular de cianobactérias.

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    The techniques used in cyanobacterial cell integrity/viability studies provide two outcomes: intact cells or not. These categorical and dichotomous values often make statistical analysis of the results difficult. In this context, the aim of this paper is to present two methodologies for the analysis of these data, showing a detailed sequence of procedures that allow analyzing, with the necessary statistical accuracy, categorized cell integrity data. For this, 3600-records database was used with the results of cellular integrity of Dc and Rr. Among the results, the traditional approach proved appropriate to identify the association between causes and effect respecting the specific characteristics of each species and the odds ratio (OR) calculation allowed to measure the associations. In this multivariate approach, the estimated OR requires a differentiated interpretation in relation to the traditional approach since the estimates are adjusted for the effect of all other variables of the model

    Internal loading potential of phosphorus in reservoirs along a semiarid watershed.

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    All rights reserved. Sediments are important to nutrient dynamics, especially due to phosphorus internal loading. Several studies have observed that internal loading could prevent water quality from improving in lakes, even when external phosphorus loading is significantly decreased. Therefore, there is an urgent need to assess the potential release of phosphorus contained in the sediment, and thus, its potential to impact water quality. In this study, the vertical and horizontal distributions of distinct phosphorus forms in the bottom sediments of artificial reservoirs, located at Forquilha watershed (Ceará, Brazil), were investigated through sequential chemical fractionation. The reservoirs Lagoa Cercada (R#1), Riacho do Algodão (R#2), Riacho Verde (R#3), Cachoeira (R#4), Chagas Manu (R#5), Quandu (R#6) and Balanças (R#7) were investigated. Reservoirs R#1 (most downstream reservoir of the watershed) and R#7 (most upstream reservoir of the watershed) had higher concentrations of total phosphorus (PT) and lower pH values, potentially exerting greater influence in phosphorus concentration in the water column. Reservoirs R#3 and R#4 presented a predominance of residual phosphorus (PRe), the least available fractions of phosphorus and thus, presented a lower potential for internal loading. Reservoirs R#5, R#1 and R#2 showed a tendency of decreasing total phosphorus (PT) as the sediment depth increased, probably indicating an increase of allochthonous phosphorus loading along time. Reservoir R#6 showed the predominance of PFeAl and PCa fractions on points A and B, respectively, showing that the characteristics of the sediments may vary in the same reservoir. Mobile (PM) and iron and aluminum-bound phosphorus (PFeAl) were the least and the most abundant fractions in most of the samples analyzed, respectively
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