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	Provedor de dados R. Bras. Zootec. (1) Autor Corrêa,Eduardo Simões (1) Costa,Fernando Paim (1) Lobato,José Fernando Piva (1) Torres Júnior,Roberto Augusto de Almeida (1) Vieira,Antonio (1) Palavra-chave Cria e recria de fêmeas (1) Peso e idade à primeira cria (1) Peso à desmama (1) Taxa de desmama (1) Taxa de prenhez (1) Tipo do documento Info:eu-repo/semantics/article (1) Ano 2006 (1) País Brazil (1) Idioma Português (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 198 Primeira ... 2 3 4 5 6 7 8 9 10 ... Última IS Annona emarginata CAPABLE OF ACCUMULATE ESSENTIAL HEAVY METALS WITHOUT DAMAGES IN THE METABOLISM? Rev. Bras. Frutic. BARON,DANIEL; AMARO,AMANDA CRISTINA ESTEVES; MACEDO,ANA CLAUDIA; BOARO,CARMEN SÍLVIA FERNANDES; FERREIRA,GISELA. ABSTRACT This study aimed to evaluate if ionic strength variation causes differential accumulation of heavy metals in plants of Annona emarginata (Schltdl.) H. Rainer var. ‘terra-fria’, modifying gas exchange and dry matter production. The seedlings were cultivated under different ionic strengths of the ‘Hoagland and Arnon’s’ nutrient solution (75% I, 50% I and 25% I). At 180 days after the application of the treatments, the effects of the essential heavy metals on the physiological parameters and foliar ionic concentration were assessed. The leaf gas exchanges and vegetative growth were affected by the variation in the essential heavy metals, with positive effects on the plants that were treated with 75%I. The seedlings that were grown under 75% I... Tipo: Info:eu-repo/semantics/article Palavras-chave: Heavy metals; Ionic strength; Mineral nutrition; Photosynthesis. Ano: 2017 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-29452017000400202 Rehabilitation with forage grasses of an area degraded by urban solid waste deposits R. Bras. Zootec. Miranda,Vanessa Soares; Ribeiro,Karina Guimarães; Silva,Alexandre Christófaro; Pereira,Rosana Cristina; Pereira,Odilon Gomes; Torrado,Pablo Vidal; Fernandes,José Sebastião Cunha; Oliveira,Maxwel Coura. Dry matter yield and chemical composition of forage grasses harvested from an area degraded by urban solid waste deposits were evaluated. A split-plot scheme in a randomized block design with four replicates was used, with five grasses in the plots and three harvests in the subplots. The mineral content and extraction and heavy metal concentration were evaluated in the second cut, using a randomized block design with five grasses and four replicates. The grasses were Brachiaria decumbens cv. Basilisk, Brachiaria ruziziensis, Brachiaria brizantha cv. Marandu and cv. Xaraés, and Panicum maximum cv. Tanzânia, cut at 42 days of regrowth. The dry matter yield per cut reached 1,480 kg ha-1; the minimum crude protein content was 9.5% and the average neutral... Tipo: Info:eu-repo/semantics/article Palavras-chave: Brachiaria spp.; Dry matter yield; Heavy metals; Mineral extraction; Tanzania grass. Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982012000100003 The effect of physical and chemical parameters on the macroinfaunal community structure of San Vicente bay, Chile RChHN SIEMENS,ROCÍO A.; MUDGE,STEPHEN M.; CANCINO,JUAN M.. San Vicente bay is a heavily industrialised bay located in central Chile, which has a sand beach extending from an area of recreational use in the south to an area of industrial use and discharge in the north. A survey of the macrofauna in the intertidal zone revealed a non-homogeneous distribution; a maximum of five invertebrate species were found with all five only occurring in one of six transects down the beach. The density ranged from 0 to 188 individuals m-2, with the highest density at the recreational end. The most common species, Emerita analoga (Stimpson), was chosen to study the macrofaunal response to beach morphodynamics, physicochemical parameters and metal concentrations. The E. analoga distribution was not significantly correlated with the... Tipo: Journal article Palavras-chave: Intertidal macrofauna; Central Chile; Sandy beaches; Beach morphodynamics; Interstitial water; Heavy metals. Ano: 2001 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2001000200017 Preliminary observations of cadmium and copper effects on juveniles of the polychaete Capitella sp. Y (Annelida: Polychaeta) from Estero del Yugo, Mazatlán, México RChHN MÉNDEZ,NURIA; GREEN-RUIZ,CARLOS. The effects of cadmium (Cd) and copper (Cu) on cultured juveniles of Capitella sp. Y were investigated. Seven-day old juveniles were exposed to 13 (control), 60, 160, 240 and 340 mg Cd L-1 and 17 (control), 50, 120 and 150 mg Cu L-1 for 30 days. Mortality significantly increased with increasing Cu concentrations, but in Cd exposures, it was only evident at 340 mg L-1. Body size and faecal pellet production were reduced earlier in juveniles exposed to Cu than those exposed to Cd, especially in the higher Cu concentrations. These facts indicate that juveniles are more sensitive to Cu in terms of mortality, feeding and growth. Haemoglobin production was inhibited due to the scarcity of food in the experimental sediment rather than to metal exposure. Tube... Tipo: Journal article Palavras-chave: Bioassays; Marine worms; Mortality; Juveniles; Heavy metals. Ano: 2005 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2005000400009 Cadmium and copper adsorption on bentonite: effects of pH and particle size Rev. Ciênc. Agron. Chaves,Lúcia Helena Garófalo; Tit,Gilvanise Alves. Reactions of heavy metals with clay minerals are important in determining metal fates in the environment. However, the adsorption process of these metals by the bentonite has been extensively investigated. The objectives of this work were to assess the ability of bentonite clay to adsorb cadmium and copper and to study the effects of pH and particle size upon these metals adsorption. Adsorption isotherms were obtained from batch adsorption experiments, with increasing cadmium and copper concentrations (5-200 mg L-1). To find out the effects of pH and particle size on adsorption, the experiments were conducted at pH 4; 5 and 6 using particles sizes of < 0.5 mm and 0.5 to 2.0 mm . The difference between initial and final cadmium and copper concentrations... Tipo: Info:eu-repo/semantics/article Palavras-chave: Clay mineral; Heavy metals; Isotherms; Langmuir. Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902011000200004 Multivariate analyses to establish reference values for soils in Médio Paraíba, state of Rio de Janeiro, Brazil Rev. Ciênc. Agron. Mattos,Amanda Guimarães de; Lima,Erica Souto Abreu; Amaral Sobrinho,Nelson Moura Brasil do; Zoffoli,Hugo José de Oliveira; Pérez,Daniel Vidal. ABSTRACT Quality Reference Values (QRVs) for potentially toxic elements are obtained from background levels in soils. However, this determination from mean values or percentiles is not appropriate given the variability in the natural distribution of these elements in soils. Therefore, the objective of this study was to propose a new methodology to establish the QRVs, using the Médio Paraíba region (RJ, Brazil) as an example, from groups of soils defined based on the pseudo-total levels of B, Ba, Co, Cr, Cu, Ni, Pb, and Zn through the use of multivariate analyses and discriminant functions. A total of 40 points, collected at depths of 0-20 and 20-40 cm, were used for the determination of pseudo-total contents, according to the EPA 3051A methodology. The... Tipo: Info:eu-repo/semantics/article Palavras-chave: Guiding values; Heavy metals; Cluster analysis. Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902018000100001 Solute Interactions in Soils in Relation to Bioavailability and Remediation of the Environment R.C. Suelo Nutr. Veg. Bolan,N.S; Ko,B.G; Anderson,C.W.N; Vogeler,I. Tipo: Journal article Palavras-chave: Phytoremediation; Heavy metals; Soil remediation. Ano: 2008 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-27912008000400002 Bioavailability of cadmium and lead in a soil amended with phosphorus fertilizers Scientia Agricola Mendes,Alessandra Monteiro Salviano; Duda,Gustavo Pereira; Nascimento,Clístenes Williams Araújo do; Silva,Michelangelo Oliveira. Phosphorus fertilizers are essential to obtain high productivity, however, they contain heavy metals that can contaminate the soil and threat the health of animals and humans. The present study focused the determination of Cd and Pb concentrations in different phosphorus fertilizers as well as the absorption of these heavy metals by velvet green bean grown on soil amended with such fertilizers. The experiment was set up as a completely randomized design in a factorial scheme. The factors were four phosphorus sources (triple superphosphate-TS, Yorin thermophosphate-YT, Araxa rock phosphate-AP, and Gafsa rock phosphate-GP) applied at five rates (0, 92, 183, 275, and 366 kg ha-1 of P2O5). The data obtained were submitted to variance and regression analysis.... Tipo: Info:eu-repo/semantics/article Palavras-chave: Heavy metals; Phytoextraction. Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000400003 Routine soil testing to monitor heavy metals and boron Scientia Agricola Abreu,Cleide Aparecida de; van Raij,Bernardo; Abreu,Mônica Ferreira de; González,Antonio Paz. Microelements are an important issue in agriculture, due to their need as micronutrients for plants and also to the possibility of the build-up of toxic levels for plants and animals. Five micronutrients (B, Cu, Fe, Mn, and Zn) are routinely determined in soil analysis for advisory purposes. Other four elements (Cd, Cr, Pb, and Ni) are considered environmentally important heavy metals in farmland soils. Thus high contents of these metals in cropland might go eventually unnoticed. In this paper we present an approach that can be used to monitor the contents of the nine elements in farmland soils using advisory soil testing. A total of 13,416 soil samples from 21 Brazilian states, 58% of them from the state of São Paulo, sent by farmers were analyzed. Boron... Tipo: Info:eu-repo/semantics/article Palavras-chave: Soil analyses; Micronutrients; Heavy metals; Deficiency; Toxicity; Interpretation limits. Ano: 2005 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000600009 Copper, nickel and zinc phytoavailability in an oxisol amended with sewage sludge and liming Scientia Agricola Martins,Adão Luiz Castanheiro; Bataglia,Ondino Cleante; Camargo,Otávio Antonio de. Contents of heavy metal on agricultural soils have been raised by land applications of sewage sludge and may constitute a hazard to plants, animals and humans. A field experiment was carried out from 1983 to 1987, to evaluate the long-term effect of sewage sludge application, with and without liming, on heavy metal accumulation and availability in a Rhodic Hapludox soil grown with maize (HMD 7974 hybrid). Trials were set up in a completely randomized blocks design with four replications. Each block was split in two bands, one with and another without liming. The sludge was applied in each band at rates: 0, 20, 40, 60 and 80 Mg ha-1 (dry basis) in a single application; and 40, 60 and 80 Mg ha-1 split in two, three and four equal yearly applications,... Tipo: Info:eu-repo/semantics/article Palavras-chave: DTPA; Mehlich-3; Heavy metals; Extractability; Corn. Ano: 2003 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162003000400021 Background levels of some trace elements in weathered soils from the Brazilian Northern region Scientia Agricola Fadigas,Francisco Souza; Amaral Sobrinho,Nelson Moura Brasil do; Anjos,Lucia Helena Cunha dos; Mazur,Nelson. Soils formed from the Barreiras Group sediments, located mainly along the coast of Brazil Northern and Northeastern regions, generally present low concentrations of iron oxides and total organic carbon, high quantities of quartz in the sand fraction, and kaolinitic clay mineralogy. The objective of the present study was to quantify the pseudo total concentrations of Cd, Co, Cu, Cr, Mn, Ni, Zn and Fe in Xhantic Udox and Xhantic Udult soils derived from these sediments. The reference sites were covered by native vegetation and located in the States of Pará and Amapá, Brazil. Multiple linear regression analysis was applied to determine correlations between soil parameters and the levels of these metals. The best correlation was obtained between Fe, Mn, clay,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Udox; Udult; Heavy metals; Metal soil estimation; Multiple linear regression. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000100008 Phytoextraction: a review on enhanced metal availability and plant accumulation Scientia Agricola Nascimento,Clístenes Williams Araújo do; Xing,Baoshan. Phytoextraction has emerged as a novel approach to clean up metal-polluted soils in which plants are used to transfer toxic metals from soils to shoots. This review provides a synthesis of current knowledge on phytoextraction of metals from soils and their accumulation in plants. The objective is to integrate soil-related (root exudates and chemical amendments) and biological advances to suggest research needs and future directions. As far as can be deduced from the literature, it will be some time before phytoextraction may be established as a commercial technology. For chemically-assisted phytoextraction, research has not shown easily biodegradable compounds to overcome the risks associated with the use of EDTA for poorly available metals in soils. On... Tipo: Info:eu-repo/semantics/article Palavras-chave: EDTA; Phytoremediation; Heavy metals; Organic acids. Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000300014 Zinc availability for corn grown on an oxisol amended with flue dust Scientia Agricola Santos,Gláucia Cecília Gabrielli dos; Berton,Ronaldo Severiano; Camargo,Otávio Antônio de; Abreu,Mônica Ferreira de. The costs related to the construction and maintenance of industrial landfills, and the environmental risks that they may represent, have increased the interest of several types of industries in studying the possibility of applying residues to agricultural soils. This study evaluates the efficiency of flue dust as a zinc source for corn, and the zinc availability for corn evaluated by four methods. A greenhouse experiment carried out at Campinas, SP, Brazil, evaluated the effect of two zinc sources (flue dust and zinc sulphate), at three rates (5, 50 and 150 mg dm-3), in one soil (Rhodic Hapludox) under two pH conditions (5.0 and 6.0). The treatments were arranged in a randomized factorial scheme design with three replications. Zinc availability indexes... Tipo: Info:eu-repo/semantics/article Palavras-chave: DTPA; Heavy metals; Industrial wastes; Speciation; Soil pH. Ano: 2006 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162006000600008 Chemical amendment and phytostabilization of an industrial residue contaminated with Zn and Cd Scientia Agricola Santos,Fabiana Soares dos; Magalhães,Márcio Osvaldo Lima; Mazur,Nelson; Amaral Sobrinho,Nelson Moura Brasil do. Phytostabilisation of a contaminated soil with heavy metals is considered a very appropriate technology to reduce erosion and dispersion of contaminants. A greenhouse study was conducted to evaluate the effects of both chemical amendments (calcium silicate and brewery sludge), and phytoremediation using the grass Brachiaria decumbens, on an industrial residue contaminated with Zn and Cd (industrial residue). Industrial residue samples placed into 30 L containers were amended with 20% brewery sludge, calcium silicate (2%, 3%), and 20% of brewery sludge + calcium silicate (2.5%, 4%), and were compared to the control treatment (non-amended residue). After pH stabilization, B. decumbens plants were grown on all treatments in order to evaluate the ability of... Tipo: Info:eu-repo/semantics/report Palavras-chave: Phytoremediation; Inertization; Contamination; Heavy metals. Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162007000500008 Adsorption of Cd, Cu, Ni and Zn in tropical soils under competitive and non-competitive systems Scientia Agricola Moreira,Cindy Silva; Alleoni,Luís Reynaldo Ferracciú. The adsorption of heavy metals in soils affects their behavior in the environment and their bioavailability to plants. The knowledge of the adsorption mechanisms in competitive systems allows a more realistic evaluation of the metals' behavior in the soil than the single metal adsorption. The objectives of this study were (i) to evaluate Cd, Cu, Ni, and Zn adsorption in 14 surface samples (0-0.2 m) of representative soils of the Brazilian humid-tropical region, in competitive and non-competitive systems, and (ii) to establish metal affinity sequences for each soil, based in the maximum adsorption capacity (MAC) estimated by the Langmuir model. The Rhodic Eutrudox, the Kandiudalf Eutrudox, the Arenic Hapludalf, the Arenic Hapludult and the Typic Argiudoll... Tipo: Info:eu-repo/semantics/article Palavras-chave: Heavy metals; Competition; Tropical soil. Ano: 2010 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000300008 Determining the geographical origin of lettuce with data mining applied to micronutrients and soil properties Scientia Agricola Maione,Camila; Araujo,Eloá Moura; Santos-Araujo,Sabrina Novaes dos; Boim,Alexys Giorgia Friol; Barbosa,Rommel Melgaço; Alleoni,Luís Reynaldo Ferracciú. ABSTRACT Lettuce (Lactuca sativa) is the main leafy vegetable produced in Brazil. Since its production is widespread all over the country, lettuce traceability and quality assurance is hampered. In this study, we propose a new method to identify the geographical origin of Brazilian lettuce. The method uses a powerful data mining technique called support vector machines (SVM) applied to elemental composition and soil properties of samples analyzed. We investigated lettuce produced in São Paulo and Pernambuco, two states in the southeastern and northeastern regions in Brazil, respectively. We investigated efficiency of the SVM model by comparing its results with those achieved by traditional linear discriminant analysis (LDA). The SVM models outperformed the... Tipo: Info:eu-repo/semantics/article Palavras-chave: ICP–OES; Traceability; Tropical soils; Heavy metals; Feature selection. Ano: 2022 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162022000100901 Cadmium voltametric quantification in table chocolate produced in Chiquinquira-Boyaca, Colombia Acta Agron. (Palmira) Chaparro-Acuña,Sandra Patricia; Vargas-Moreno,Paola Andrea; Silva-Gómez,Leonardo Andrés; Cárdenas,Oswaldo Eliécer. Abstract: Bioaccumulation of heavy metals such as cadmium has been a major concern in scientific communities and international food organizations, given the great toxicological risk to the consumer, and in many places there is no detailed record of its actual content. In this way, the need arises to carry out a study and registration of the concentration of this metal in products such as table chocolate, of great consumption at regional and national level. Likewise, we seek to have effective quantification tools and a reliable and affordable method to achieve the aim of this research. In this research, Cadmium content in powdered and granulated table chocolate was determined, elaborated and commercialized in the municipality of Chiquinquira,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Food; Cocoa; Electrochemistry; Heavy metals; Validation. Ano: 2017 URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122017000200172 Soil bacteria that precipitate calcium carbonate: mechanism and applications of the process Acta Agron. (Palmira) Chaparro-Acuña,Sandra Patricia; Becerra-Jiménez,Mónica Liliana; Martínez-Zambrano,José Jobanny; Rojas-Sarmiento,Hugo Alfonso. Abstract Bacteria with ureasic activity are microorganisms found in soil that in presence of urea and calcium, they can produce calcium carbonate, a process known as microbiologically induced calcium carbonate precipitation (MICP). This article discusses this process and its mechanism, as well as bacterial urease, calcium carbonate crystals formed, and factors that affect the efficiency of MICP, as type of bacteria, bacterial cell concentrations, pH, temperature and calcium and urea concentrations. In addition, applications as removal of heavy metals in water, bioconsolidation, biocement and CO2 sequestration are also discussed. Tipo: Info:eu-repo/semantics/article Palavras-chave: Biomineralization; Bacillus; Urease; Carbonates; Heavy metals; Bioconsolidation; Biocementation. Ano: 2018 URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-28122018000200277 Total mercury in wild felids occurring in protected areas in the central Brazilian Amazon Acta Amazonica LOPES,Marcelly Castello Branco; CARVALHO,Gabriel Oliveira de; BERNARDO,Robson Roney; MACEDO,Joana; LINO,Adan Santos; RAMALHO,Emiliano Esterci; KASPER,Daniele; MEIRE,Rodrigo Ornellas; TORRES,João Paulo Machado; MALM,Olaf. ABSTRACT This is the first study to investigate mercury (Hg) contamination in felid species in the Brazilian Amazon. We collected 26 fur samples from wild felids of four species (Puma concolor, Panthera onca, Leopardus pardalis and Leopardus wiedii) occurring in the Mamirauá and Amanã sustainable development reserves, in the state of Amazonas. Samples were from museum specimens, except for five P. onca samples collected from free-living individuals. Total Hg concentrations ranged from 0.12 to 48.1 µg g-1. Concentrations of Hg did not differ significantly between museum specimens and live individuals of P. onca, but varied significantly among species, with significantly higher concentrations for P. onca and L. pardalis, which could be related to factors... Tipo: Info:eu-repo/semantics/article Palavras-chave: Conservation; Mammals; Bioaccumulation; Fur; Heavy metals. Ano: 2020 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672020000200142 Mercury Levels in Eggs, Embryos, and Neonates of Trachemys callirostris (Testudines, Emydidae) Acta biol.Colomb. RENDÓN-VALENCIA,BEATRIZ; ZAPATA,LINA M; C. BOCK,BRIAN; PÁEZ,VIVIAN P.; PALACIO,JAIME A.. We quantified total mercury concentrations in eggshells, egg yolks, and embryos from 16 nests of the Colombian Slider (Trachemys callirostris). Nests were collected in different stages of development, but estimated time of incubation in natural substrates was not correlated with mercury levels in the eggs, suggesting that mercury was not absorbed from the substrate, but more likely passed on to the embryos during folliculogenesis by the reproductive females who had bioaccumulated the mercury from environmental sources. Mean mercury concentrations were higher in embryos than in eggshells or egg yolks, indicating that embryos also bioaccumulate mercury present in other egg tissues. Intra-clutch variation in egg yolk mercury concentrations was relatively... Tipo: Info:eu-repo/semantics/article Palavras-chave: Bioaccumulation; Colombian slider; Heavy metals; Mercury; Yolk. Ano: 2014 URL: http://www.scielo.org.co/scielo.php?script=sci_arttext&pid=S0120-548X2014000300016 Registros recuperados: 198 Primeira ... 2 3 4 5 6 7 8 9 10 ... Última

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