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Registros recuperados: 165 | |
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Richardi,Vinicius Sobrinho; Vicentini,Maiara; Rebechi,Débora; Fávaro,Luis Fernando; Navarro-Silva,Mário Antônio. |
ABSTRACTChironomidae immature are used as bioindicators of sediment quality in aquatic ecosystems and ecotoxicological assays. Histological descriptions for this family are outdated and limited and there are no studies with Neotropical species. The aim of this study was to describe the tissue architecture of several organs of the larva of Chironomus sancticaroli. For the description of the histological pattern, the larvae were fixed in Duboscq solution for insects at 56 °C, followed by routine histologic processing, infiltration in paraffin, and the sections were stained with Hematoxylin–Eosin. After examining the slides, the tube digestive, salivary gland, excretory, nervous, endocrine, circulatory, and integumentary systems and fat body were... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ecotoxicology; Histological biomarker; Sediment. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0085-56262015000300240 |
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Fadini,Lauana Schneider; Silva,Ary Gomes; Ferreira-Júnior,Paulo Dias. |
The beaches of Espírito Santo encompass the most important nesting sites of the loggerhead sea turtle, Caretta caretta (Linnaeus, 1758), in the South Atlantic Ocean. Previous research has shown that, unlike other nesting sites in Brazil, Espírito Santo harbors a large percentage of male individuals, which play an important role in maintaining the equilibrium of C. caretta populations in the South Atlantic. During the 2006/2007 reproductive season, four beaches presenting considerable geologic differences were monitored. The sedimentary features of the nesting sites (mineral composition, albedo, and grain size), nesting dates, and clutch sizes were correlated with hatching success and incubation duration. Results show that hatching success is mostly... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Loggerhead sea turtle; Ecology; Nest; Sediment; Hatchling. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000300005 |
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Spivak,Eduardo D.; Bas,Claudia C.; Luppi,Tomás A.. |
ABSTRACT Two populations of the Southwestern Atlantic burrowing crab, Neohelice granulata (Dana, 1851), are separated by only 190 km. They inhabit bays that drain into a Patagonian gulf in the southernmost limit of the geographical distribution of the species: San Antonio Bay (SAO) and San José Gulf (RSJ). The population from SAO has been extensively studied, whereas that of RSJ has not. The main goal of this study is to compare the ecological and habitat characteristics of the two populations, based on samples collected on successive days during the middle of the reproductive season of the crab. The substrate of SAO is composed of a high proportion of gravel and scarce organic matter, whereas the substrate of RSJ presents twice as much silt and clay, and... |
Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Argentine; Estuaries; Crab; Fecundity; Feeding; Growth; Maturity; Sediment. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702016000604001 |
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Galdos,Marcelo Valadares; De Maria,Isabella Clerici; Camargo,Otávio Antonio de; Dechen,Sonia Carmela Falci. |
The use of sewage sludge in agricultural soils as a macro and micronutrient source and as a soil conditioner has been one of the alternatives for its disposal. However, sewage sludge contains trace metals, which are potential sources of pollution. The goal of this study was to evaluate the effect of sewage sludge application on surface water contamination through runoff when it was applied in a soil cultivated with corn. The effect of sludge application on the concentration and load of copper, nickel and zinc and the volume of runoff water and sediment were evaluated. The experiment was set up in plots used to study erosion losses in Campinas, Sao Paulo State, Brazil. The soil is a clayey Rhodic Hapludox. Three treatments were studied: no sewage sludge,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cu; Ni; Zn; Erosion; Sediment. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000300012 |
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Bertol,Ildegardis; Guadagnin,Jean Cláudio; González,Antonio Paz; Amaral,André Júlio do; Brignoni,Leonardo Felipe. |
Soil tillage influences water erosion, and consequently, losses of calcium, magnesium and organic carbon in surface runoff. Nutrients and organic carbon are transported by surface runoff in particulate form, adsorbed to soil colloids or soluble in water, depending on the soil tillage system. This study was carried out on an Inceptisol, representative of the Santa Catarina highlands, southern Brazil, between November 1999 and October 2001, under natural rainfall. The soil tillage treatments (no replications) were: no-tillage (NT), minimum soil tillage with chiseling + disking (MT), and conventional soil tillage with plowing + two diskings (CT). The crop cycles sequence was soybean (Glycine max), oats (Avena sativa), beans (Phaseolus vulgaris) and vetch... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Runoff; Sediment; Nutrient in runoff; Nutrient in sediments; Nutrient losses. |
Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000600011 |
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Pinheiro,Marcelo Antonio Amaro; Fransozo,Adilson; Negreiros-Fransozo,Maria Lúcia. |
The niche breadth of the Portunidae and their overlap on the subtidal sediments of Fortaleza bay, Ubatuba (São Paulo) was analyzed. Samples were made monthly from November/1988 to October/1989, inseven areas of the bay using a shrimp fishery boat equipped with two otter-trawls. Each area was characterized based on environmental factors such as depth, temperature, salinity, dissolved oxygen, organic matter and granulometric composition of the sediment. The number of individuais of each species was registered to each area (resource). Levins's standardized measure (BA) and niche percentage were calculated. Five species of swimming crabs were recorded in this study: Callinectes ornatus Ordway, 1863, Arenaeus cribrarius (Lamarck, 1818), Portunus spinimanus... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Portunidae; Distribution; Niche; Sediment; Swimming crab. |
Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81751997000200010 |
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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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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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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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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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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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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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Registros recuperados: 165 | |
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