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| Registros recuperados: 167 | |
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| Silva,Cesar A.; Madureira,Luiz A.S.. |
| The relative distribution of several compounds identified in four samples of recently deposited sediments of the Itacorubi Mangrove located on the Santa Catarina Island, southern Brazil, was compared with similar data on compounds extracted from fresh leaves of three mangrove species (Avicennia schaueriana, the dominant species in the area, Rhizophora mangle and Laguncularia racemosa) and the Gramineae Spartinna alterniflora. Terpenols, previously identified in mangrove species in northern Brazil, were also found. A. schaueriana mainly contains β-amyrin (90.6 μg g-1 of extractable organic matter); low amounts of friedelin, betulin and germanicol were detected only in the leaf extract of this species. R. mangle also contained a significant amount of... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Biomarkers; Leaf; Mangrove; Santa Catarina; Sediment. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652012000300002 |
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| FARIA,MARCIA DE MELO; SANCHEZ,BRAZ A.. |
| Geochemical and clay mineralogical studies of bottom sediments collected along the Macacu and Caceribu rivers and Guanabara Bay were carried out in order to investigate the relationship between major source areas and recent sediments of the bay. Clay mineralogy includes different groups with selective distribution conditioned by geomorphic features and depositional settings. Micaceous clay minerals are abundant near parent rock in the upper course, whereas kaolinite derived from varied sources is gradually concentrated towards the estuary. In the Guanabara Bay, kaolinite accumulates near river mouths, while micaceous clay minerals are converted into mixed layers in the estuary. Analyses of heavy metal contents reveal higher levels of Zn and Cu in sediments... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heavy metal; Clay mineral; Sediment; Guanabara Bay. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652001000100010 |
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| BURONE,LETICIA; MUNIZ,PABLO; PIRES-VANIN,ANA MARIA S.; RODRIGUES,MARCELO. |
| Analyses of organic matter content, organic carbon, nitrogen, sulfur and granulometric variables were performed on 101 surface sediment samples from Ubatuba Bay in order to investigate the spatial distribution of organic matter, its origin and the relationships among its components. The samples were obtained with a manual corer, from water depths between 1 and 15m during 5 cruises of the R/V "Veliger II'', two months apart. Pearson correlation, regression and Principal Component Analysis (PCA) statistical methods were used to analyze the data. Strong correlations between organic matter and fine sediment fractions were obtained. The PCA revealed at least two main sample groups that reflect the different environmental conditions prevalent in the bay. There... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic matter; Sediment; C/N ratio; Ubatuba; Brazil. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652003000100009 |
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| LESSA,GUILHERME C.; BITTENCOURT,ABÍLIO C.S.P.; BRICHTA,ARNO; DOMINGUEZ,JOSÉ M. L.. |
| Todos os Santos Bay is a large (<img ALIGN="BOTTOM" BORDER="0" SRC="http:/img/fbpe/aabc/v72n4/0052img1.gif" ALT="$ \approx$"> 1000 km²), structurally controlled tidal bay in northeast Brazil. Three main drainage basins debouch into the bay, providing a mean freshwater discharge of 200 m³/s (prior to 1985), or less than 1% of the spring tidal discharge through the bay mouth. Based on the result of several sedimentological studies performed in the 1970's, five surface sedimentary facies were identified inside the bay, namely i) transgressive siliciclastic marine sand facies; ii) transgressive bay sand-mud facies; iii) a transgressive carbonate marine sand facies; iv) regressive bay-mud facies, and v) regressive fluvial sand facies. The spatial... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Estuary; Sediment; Stratigraphy; Holocene. |
| Ano: 2000 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652000000400008 |
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| SCHNEIDER,ISMAEL L.; TEIXEIRA,ELBA C.; RODRIGUES,MARIA LUCIA K.; ROLIM,SILVIA B.A.. |
| The present study aimed to evaluate Cu, Cr, Ni, Zn, Pb, Mn, Al, and Fe contents, as well as their geochemical partitioning in Sinos River basin sediments in southern Brazil. This basin is a densely populated area with a substantial number of industries, especially metallurgy, electroplating works, steel mills, petrochemicals, and tanneries. The total metal concentrations were determined by X-ray fluorescence and the sediment phase concentrations were determined by applying the BCR-701 sequential extraction method proposed by the Community Bureau of Reference of the European Community, using ICP/OES. The contents extracted by a solution of 0.5 mol/L HCl were also considered. Metal contents were evaluated in the sediment fraction <63 µm. Results in the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: BCR-701; Metals; Sediment; Sequential extraction. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000301043 |
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| Salemi,Luiz Felippe; Lins,Silvia Rafaela Machado; Ravagnani,Elizabethe de Campos; Magioli,Marcelo; Martinez,Melissa Gaste; Guerra,Fernando; Vidas,Natassia Bonini; Fransozi,Aline; Ferraz,Silvio Frosini de Barros; Martinelli,Luiz Antonio. |
| Abstract In this article, by using carbon stable isotopes, we assessed the past and present land use influences that riparian areas are subject within agricultural landscapes. Emphasis is given to the understanding of the effects of the 2012 Brazilian Forest Act on such areas. We selected five riparian areas within a highly C4 dominated agricultural landscape. Three of them had 30 meters native riparian forest buffer (NRFB) and two of them had 8 meter and no NRFB. We used three 100 meter-transects located 5, 15 and 30 meters relative to stream channel to obtain soil samples (0 - 10 cm). All riparian areas presented soil carbon isotopic signatures that are not C3 (native forests) irrespective of having or not 30 meters NRFB. Two cases presenting less than... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Watershed; Soil degradation; Organic matter; Sediment; Carbon cycling. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032016000200210 |
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| Cesar,Augusto; Abessa,Denis Moledo de Souza; Pereira,Camilo Dias Seabra; Santos,Aldo Ramos; Fernández,Nuria; Choueri,Rodrigo Brasil; DelValls,Tomas Angel. |
| In this work, multivariate and numeric methods were used to integrate the chemical and ecotoxicological data obtained for the sediments from the Santos Estuarine System, and for the vicinity of the discharges of the Submarine Sewage Outfall of Santos, in order to establish more accurately the environmental risks, identify the priority areas and thus provide guidance to control the programs and public policies. For both the datasets, the concentrations which exceeded numeric sediment guidelines tended to be associated to toxicity. For the estuary, this trend was corroborated by the correlations between the toxicity and Cu and PAHs levels, whereas for the sewage outfall region, this was observed through the correlation between the toxicity and Hg contents.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sediment; Contamination; Toxicity; Tiburonella viscana; Environmental risk assessment. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132009000100028 |
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| Goatley, Christopher H. R.; College of Marine and Environmental Sciences, James Cook University; Australian Research Council Centre of Excellence for Coral Reef Studies; christopher.goatley@jcu.edu.au; Fox, Rebecca J.; College of Marine and Environmental Sciences, James Cook University; Australian Research Council Centre of Excellence for Coral Reef Studies; Division of Evolution, Ecology and Genetics, Australian National University; School of Life Sciences, University of Technology Sydney; rebecca.fox-1@uts.edu.au; Bellwood, David R.; College of Marine and Environmental Sciences, James Cook University; Australian Research Council Centre of Excellence for Coral Reef Studies; david.bellwood@jcu.edu.au. |
| Around the world, the decreasing health of coral reef ecosystems has highlighted the need to better understand the processes of reef degradation. The development of more sensitive tools, which complement traditional methods of monitoring coral reefs, may reveal earlier signs of degradation and provide an opportunity for pre-emptive responses. We identify new, sensitive metrics of ecosystem processes and benthic composition that allow us to quantify subtle, yet destabilizing, changes in the ecosystem state of an inshore coral reef on the Great Barrier Reef. Following severe climatic disturbances over the period 2011-2012, the herbivorous reef fish community of the reef did not change in terms of biomass or functional groups present. However, fish-based... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Disturbances; Ecosystem state; Herbivory; Management; Monitoring; Processes; Resilience; Sediment; Thresholds. |
| Ano: 2016 |
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| Jones, Krista L; Institute of Ecology, University of Georgia; kjones@eco-metrics.com; Poole, Geoffrey C; Eco-metrics, Inc. and Institute of Ecology, University of Georgia; gpoole@eco-metrics.com; Meyer, Judy L; Institute of Ecology, University of Georgia; jlmeyer@uga.edu; Bumback, William; River Basin Center, University of Georgia; wbumback@uga.edu; Kramer, Elizabeth A; Natural Resources Spatial Analysis Laboratory, University of Georgia; lkramer@uga.edu. |
| Regulations governing the management of streamside vegetation (riparian buffers) lie at a nexus between environmental, social, and land development interests, and can yield especially contentious debates among stakeholders. In 2001, the State Legislature of Georgia, USA, took up this debate; the Legislature reduced the minimum width of mandatory-forested riparian buffers along designated trout streams from ∼30 m (100 ft) to ∼15 m (50 ft), and commissioned this study to assess the expected response of existing trout populations. Because our research was designed to provide rigorous and accessible data for informing this management debate, this research may serve as a general template for other studies designed to inform regulatory and... |
| Tipo: Peer-Reviewed Reports |
Palavras-chave: Georgia; Natural resource legislation; Riparian buffer width; Scientific assessment; Sediment; Southern Appalachians; Stream temperature; Trout. |
| Ano: 2006 |
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| Cembranel,Adir S.; Sampaio,Silvio C.; Remor,Marcelo B.; Gotardo,Jackeline T.; Rosa,Pábolla M. Dalla. |
| ABSTRACT Geochemical background establishment is indispensable to determine the actual state of contamination of soils and sediments. However, no scientific consensus exists regarding the methodology for determining these values. In this context, this study aimed to establish the geochemical background in an Oxisol (Rhodic Hapludox) by means of an integrated method that uses direct and indirect soil analyses to identify the most appropriate calculation methodology. Soil samples were collected in a permanent preservation area of the Cascavel River watershed, PR, Brazil. The elements Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, and Zn present in soil samples were quantified by flame atomic absorption spectrometry. The use of a permanent preservation area is... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Trace elements; Heavy metals; Sediment; Soil. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000300565 |
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| Registros recuperados: 167 | |
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