926 resultados para Asprela and Massarelos drainage basins
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O desenvolvimento incessante em áreas urbanas ameaça a qualidade e quantidade das águas subterrâneas. O Porto é uma cidade densamente urbanizada, dominada por granitos, os quais constituem um meio fraturado anisotrópico e heterogéneo. O principal objetivo desta dissertação foi realçar a importância da cartografia hidrogeológica, bem como a relevância de realizar inventários hidrogeológicos e de potenciais focos de contaminação para compreender a vulnerabilidade dos sistemas aquíferos na cidade do Porto. Para tal, foram selecionadas as bacias hidrográficas da Asprela e de Massarelos. Assim, foram levados a cabo dois inventários, um hidrogeológico e outro das potenciais atividades de contaminação. O estudo foi apoiado pelos Sistemas de Informação Geográfica (SIG), os quais foram fundamentais para um melhor conhecimento e integração nas áreas de estudo. Previamente à implementação dos inventários foi feita uma caracterização das duas bacias, em termos geográficos, hidroclimatológicos, de ocupação do solo, geomorfológicos e hidrogeológicos. As duas bacias desenvolvem‐se, principalmente, na unidade hidrogeológica do granito de grão médio a fino, por vezes com saprólito. O inventário hidrogeológico contemplou principalmente fontanários e nascentes, tendo incluído, respetivamente, 8 e 21 pontos de água nas bacias da Asprela e de Massarelos. As águas subterrâneas são límpidas, sem turvação ou cheiro, ácidas, com mineralizações baixas a médias, temperaturas baixas e caudais muito pequenos. Quanto aos potenciais focos de contaminação, na bacia da Asprela foram reconhecidos 61, enquanto que na bacia de Massarelos foram identificados 78. A maioria destas atividades é pontual correspondendo, nomeadamente, a estabelecimentos de ensino e estações de serviço/oficinas de automóveis. Contudo, os focos lineares apresentam uma difusão significativa nas duas bacias hidrográficas. Apesar de a vulnerabilidade intrínseca à contaminação das águas subterrâneas nestas áreas ser baixa a moderada, a localização dos potenciais focos de contaminação poderá ser responsável pelo aumento da vulnerabilidade nas duas bacias estudadas. Esta metodologia demonstrou ser extremamente importante para um melhor conhecimento dos sistemas de água subterrânea do Porto e, ainda, da hidrogeologia de áreas urbanas.
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Samples of suspended, floodplain and channel bed sediment have been used to examine downstream changes in ediment-associated contaminant transport and storage in contrasting rivers in Yorkshire, UK. The concentrations of hosphorus, chromium and selected PCBs associated with sediment in the River Aire and its main tributary, the River Calder, which drain an urbanized and industrialized catchment, are considerably higher than those in the relatively unpolluted River Swale, which drains an agricultural catchment. Concentrations of sediment-associated contaminants in the Aire/Calder system increase downstream, reflecting the location of urban and industrial areas in the middle and lower reaches, and the location of point source inputs, such as sewage treatment works. The ontaminant concentrations associated with floodplain and channel bed sediment in the Rivers Aire and Calder are high, particularly in the lower reaches. This, combined with measurements of sediment storage on the floodplain and channel bed, indicate that significant storage of sediment-associated contaminants occurs in the Rivers Aire and Calder.
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The paper presents a historiographic context helpful in the current investigations of the cultural contacts between the societies of the east and west of Europe in the borderland of Podolia and moldova in the late Eneolithic and the prologue of the Bronze age . The focus is on the state of research (chiefly taxonomic and topogenetic) into the sequence of taxa in the age of early ‘barrow-building’, identified in the funerary rituals of societies settling the forest-steppe of the north- western Black Sea Coast in the 4th/3rd-2nd millennium BC .
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The paper discusses the taxonomy and autogenesis of the cycle of early ‘barrow cultures’ developed by the local communities of the middle Dniester Area or, in a broader comparative context, the north-western Black Sea Coast, in the 4th/3rd-2nd millennium BC . The purpose of the study is to conduct an analytical and conceptual entry point to the research questions of the dniester Contact area, specifically the contacts between autochthonous ‘late Eneolithic’ communities (Yamnaya, Catacomb and Babyno cultures) and incoming communities from the Baltic basin . The discussion of these cultures continues in other papers presented in this volume of Baltic-Pontic Studies.
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The article presents the present state of research on the general issue of the dniester region of cultural contacts between communities settling the Baltic and Pontic drainage basins . Some five domains of research shall be brought to discussion in which it is possible to see fresh opportunities for archaeological study, on the basis of ‘Yampil studies’ on dniester-Podolia (forest-steppe) barrow-culture ceremonial centres from the latter half of the 4th millennium and first half of the 3rd millennium BC . This relates to the peoples of the Eneolithic and the Early Bronze age . in terms of topogenesis, embracing the Pontic-Tripolye, Yamnaya and Catacomb cultures, as well as Globular amphora and Corded ware in central prehistoric Europe .
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Prepared in cooperation with U.S. Army, Corps of Engineers, Huntington District, Huntington, West Virginia.
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This paper presents a GIS-based multicriteria flood risk assessment and mapping approach applied to coastal drainage basins where hydrological data are not available. It involves risk to different types of possible processes: coastal inundation (storm surge), river, estuarine and flash flood, either at urban or natural areas, and fords. Based on the causes of these processes, several environmental indicators were taken to build-up the risk assessment. Geoindicators include geological-geomorphologic proprieties of Quaternary sedimentary units, water table, drainage basin morphometry, coastal dynamics, beach morphodynamics and microclimatic characteristics. Bioindicators involve coastal plain and low slope native vegetation categories and two alteration states. Anthropogenic indicators encompass land use categories properties such as: type, occupation density, urban structure type and occupation consolidation degree. The selected indicators were stored within an expert Geoenvironmental Information System developed for the State of Sao Paulo Coastal Zone (SIIGAL), which attributes were mathematically classified through deterministic approaches, in order to estimate natural susceptibilities (Sn), human-induced susceptibilities (Sa), return period of rain events (Ri), potential damages (Dp) and the risk classification (R), according to the equation R=(Sn.Sa.Ri).Dp. Thematic maps were automatically processed within the SIIGAL, in which automata cells (""geoenvironmental management units"") aggregating geological-geomorphologic and land use/native vegetation categories were the units of classification. The method has been applied to the Northern Littoral of the State of Sao Paulo (Brazil) in 32 small drainage basins, demonstrating to be very useful for coastal zone public politics, civil defense programs and flood management.
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Three drainage basins belonging to different drainage systems, but in close proximity, were evaluated to compare the distribution of macroalgal communities in the northwest region of São Paulo State, southeastern Brazil. Monthly samplings were carried out from September 1992 through September 1993 in three sites along the main river of each basin. 10 m length cross segments were evaluated for species per cent cover and richness, on both the population and community levels. Selected stream variables were measured: specific conductance, temperature, turbidity, mean cross-sectional area of the reach, current velocity, pH, and oxygen saturation (%). Principal Coordinate Analysis (PCO), chi-square good-of-fitness, and Pearson Product-Moment correlation coefficient were applied to evaluate the distribution of the macroalgal species. The survey resulted in 36 taxa of macroalgae, of which Cyanophyta was the dominant group (17 taxa or 41.7% of the total), followed by Chlorophyta (15 taxa or 41.7%), Rhodophyta (3 taxa or 8.3%) and Chrysophyta (1 taxon or 2.8%). Stigeoclonium helveticum, 'Chantransia' stage of Batrachospermum spp., and B. delicatulum were the most widespread and frequent macroalgae throughout the basins. The analyses showed that conductance and current velocity were the factors most closely related to the distribution of the macroalgal species. Positive correlation between richness and percent cover was determined, which reinforces the patchiness of stream macroalgal distribution.
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Mode of access: Internet.
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Mode of access: Internet.
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Mode of access: Internet.
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At head of title: U. S. Dept. of Agriculture. Soil Conservation Service.
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Study region The Galilee and Eromanga basins are located in central Queensland, Australia. Both basins are components of the Great Artesian Basin which host some of the most significant groundwater resources in Australia. Study focus This study evaluates the influence of regional faults on groundwater flow in an aquifer/aquitard interbedded succession that form one of the largest Artesian Basins in the world. In order to assess the significance of regional faults as potential barriers or conduits to groundwater flow, vertical displacements of the major aquifers and aquitards were studied at each major fault and the general hydraulic relationship of units that are juxtaposed by the faults were considered. A three-dimensional (3D) geological model of the Galilee and Eromanga basins was developed based on integration of well log data, seismic surfaces, surface geology and elevation data. Geological structures were mapped in detail and major faults were characterised. New hydrological insights for the region Major faults that have been described in previous studies have been confirmed within the 3D geological model domain and a preliminary assessment of their hydraulic significance has been conducted. Previously unknown faults such as the Thomson River Fault (herein named) have also been identified in this study.