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Registros recuperados: 174 | |
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FERNANDES, F. A.; CERRI, C. C.; FERNANDES, A. H. B. M.. |
Estudou-se uma cronosseqüência de introdução de pastagens cultivadas em áreas com 10 e 20 anos de implantação, tendo uma área de Cerrado intacto como referência. Coletaram-se amostras até 40cm de profundidade ao longo de dois transectos, para cálculo dos estoques de C e N e determinações químicas. Também abriram-se trincheiras e coletaram-se amostras de solo até 1m de profundidade, para estudo das variações nos conteúdos de C e N no perfil. Após 10 anos de cultivo, o solo apresentou aumento no teor de bases trocáveis e na capacidade de troca catiônica, e diminuição da acidez. Entretanto, após 20 anos, os teores de bases trocáveis e a capacidade de troca catiônica diminuíram e a acidez aumentou, indicando tendência do sistema de retornar ao equilíbrio... |
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Característica química; Bases trocáveis; Carbono orgânico; Frações húmicas; Chemical characteristics; Organic carbon; Humic fractions; Cultivated pasture.; Acidez; Fracionamento; Matéria Orgânica; Nitrogênio; Pastagem Cultivada; Solo.; Acidity; Pantanal; Fractionation; Exchangeable cations; Organic matter; Nitrogen; Soil.. |
Ano: 2002 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/810747 |
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Espinosa, Luisa F.; Ramírez, Gustavo; Campos, Néstor H.. |
En los sedimentos superficiales aledaños al manglar, de cuatro estaciones dentro de la Ciénaga Grande de Santa Marta y una estación en la Bahía de Chengue, se analizaron las concentraciones de seis residuos de plaguicidas organoclorados (lindano, heptacloro, aldrin, pp'DDE, pp'DDD y pp'DDT), mediante la técnica de cromatografía gas-líquido. Se realizaron muestreos trimestrales entre marzo y diciembre de 1993, tratando de abarcar las principales épocas climáticas de la región (seca, lluviosa menor, seca menor y lluviosa mayor). Mediante análisis de varianza multifactorial se encontraron diferencias significativas solamente en las concentraciones de lindano, heptacloro y pp'DDE, entre las diferentes épocas climática; los otros tres compuestos (aldrin, pp'DDD... |
Tipo: Journal Contribution |
Palavras-chave: Ecology; Chemical analysis; Salinity effects; Gas chromatography; Organic matter; Coastal lagoons; Estuaries; Mangroves; Ecology; Organic matter; Estuaries; Gas chromatography; Coastal lagoons; Mangroves; Http://aims.fao.org/aos/agrovoc/c_2467; Http://aims.fao.org/aos/agrovoc/c_5387; Http://aims.fao.org/aos/agrovoc/c_2673; Http://aims.fao.org/aos/agrovoc/c_11097; Http://aims.fao.org/aos/agrovoc/c_1697; Http://aims.fao.org/aos/agrovoc/c_16190. |
Ano: 1999 |
URL: http://hdl.handle.net/1834/3804 |
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Gonçalves,Morgana S.; Sampaio,Silvio C.; Coelho,Silvia R. M.; Suszek,Floriano L.; Cordovil,Claudia M. D. S.. |
The effects of swine wastewater on atrazine dissipation and formation of bound residues in subtropical clay soil were investigated in this study. The experiment was carried out in laboratory, under room conditions, where samples of Rhodic Hapludox soil received 168.61 mg kg-1 of atrazine and were incubated for 60 days in the following treatments: T1 (sterilized soil + swine wastewater), T2 (sterilized soil + distilled water), T3 (Non sterilized soil + swine wastewater) and T4 (Non sterilized soil + distilled water). The extractable residues and bound residues of atrazine were extracted and analyzed by high performance liquid chromatography. The results showed no effect of swine wastewater on atrazine dissipation. However, the addition of swine wastewater... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Herbicide; Degradation; Sorption; Organic matter. |
Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000600017 |
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Barrales Brito, Edgar. |
El mantillo y horizontes de fermentación (CF) es un reservorio dinámico de carbono (C) en suelos forestales. Las metodologías que cuantifican la emisión de CO2 por la descomposición son escasas y requieren periodos largos de medición. Se requieren métodos para poder generar información de la emisión de CO2 de éstas capas orgánicas en tiempos cortos de medición. Los objetivos fueron: generar un protocolo para la medición de la emisión de CO2 por la descomposición de mantillo y CF con un respirómetro manométrico (OxiTop ®). Medir los reservorios de C de mantillo y CF de bosques con diferentes condiciones. Medir la emisión de CO2 del mantillo y CF y las tasas de descomposición con un respirómetro. Analizar las características químicas de los mantillos y... |
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Palavras-chave: Biogeoquímica; Emisión de CO2; Respirometría; Materia orgánica; Bosques; Biogeochemistry; CO2 emissions; Respirometry; Organic matter; Forest; Edafología; Maestría. |
Ano: 2013 |
URL: http://hdl.handle.net/10521/2096 |
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Mercante, Fabio Martins; EMBRAPA; Silva, Rogério Ferreira da; EMBRAPA; Francelino, Silvana Fabbro; UNIGRAN; Cavalheiro, Juliana Cristina Touro; EMBRAPA; Otsubo, Auro Akio; EMBRAPA. |
Objetivou-se avaliar a influência de cultivos de mandioca, em diferentes sistemas de manejo sobre a biomassa microbiana de solo, sua atividade e índices derivados. O estudo foi conduzido no Município de Glória de Dourados, Estado do Mato Grosso do Sul, em Argissolo Vermelho, de textura arenosa, em sistema de preparo convencional, plantio direto, sobre resíduos culturais de mucuna, sorgo e milheto, além de sistema com vegetação nativa, usado como referencial para comparação. As avaliações foram realizadas em seis épocas distintas: maio/2003, junho/2003, novembro/2003, abril/2004, agosto/2004 e novembro/2004. A presença ou ausência de resíduos vegetais influenciou diretamente a microbiota do solo, indicando que o uso de plantas de cobertura, no cultivo de... |
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Palavras-chave: 5.01.00.00-9 Agronomia plantio direto; Carbono orgânico; Atividade microbiana; Manihot esculenta. no-tillage; Organic matter; Microbial activity; Manihot esculenta. |
Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/5301 |
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Zilli,Florencia; Barco,Julia del; Vanzetti,Agustín. |
ABSTRACT Currently, it is widely recognized that invertebrates play key roles in neotropical floodplains and in many other environments worldwide. However, little information has been published concerning their biometry, in spite that it represents an essential tool for many different studies. Here, we provided length-mass and length-length relationships by fitting the linearized model (log10 Y = log10a + b log10 X) and several mean biomass ratios ± SE for bivalves, gastropods, quironomids, ephemeropterans, oligochaetes and hirudineans. We measured, weighed, oven dried and incinerated to ashes specimens collected from 2005 to 2014 in the Paraná River, Argentina. The lineal equations had fit levels higher than 75% in most of the significant regressions.... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Allometry; Organic matter; Paraná River; Wetlands; Benthos; Pleuston. |
Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212017000100214 |
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Jenkinson, Ian; Claireaux, Guy; Gentien, Patrick. |
Intertidal mudflats are important nursery grounds for juveniles of many fish species. However, they are being used increasingly to farm bivalve molluscs, which produce large amounts of organic "fluff", overlying the mud. Fish such as sole, Solea solea, hide in this fluff from potential predators, but the energy consumed by respiring the fluff may be high due to its biorheological properties. We developed an ichthyoviscometer. It incorporates a freshly killed fish as a viscometer, and we developed it to measure the rheological properties of fluids and suspensions, including fluff, at scales encompassing those in gill ventilation. We have shown that the rheological behaviour of fluff is close to that of a gel with a yield stress strongly dependent on... |
Tipo: Text |
Palavras-chave: Fish; Organic matter; Gill ventilation; Biorheology; Organic fluff; Mud flats. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2219.pdf |
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Fernández, M.. |
This is a study on surficial sediments and bottom water physico-chemical characteristics of the San Jorge Gulf (SW Atlantic, Argentina)during spring 1999 - winter 2000 (first studied period), autumn 2001- summer 2002 (second studied period)and winter 2003 (third studied period), based on samples obtained during research cruises carried out on board of the INIDEP (Instituto Nacional de Investigación y Desarrollo Pesquero)research vessels. Environmental variables such as temperature, salinity, density, oxygen and bottom water chlorophyll a content as well as granulometric fractions, total organic matter, total organic carbon, total nitrogen, total phosphorous, chlorophyll a and phaeopigments in sediment concentration and depth were analyzed. The origen and... |
Tipo: Theses and Dissertations |
Palavras-chave: Physicochemical properties; Benthic environment; Organic matter; Shrimp fisheries; Benthos; Organic matter; Benthos; Physicochemical properties; Benthic environment. |
Ano: 2006 |
URL: http://hdl.handle.net/1834/3134 |
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Cuadra, T. de la; Chalén, X.; Pérez, P.; Macías, P.; Ortega, D.; Ormaza, F.. |
Las masas de agua encontradas a partir de las variables de estado, indican una contribución muy pobre de Agua Subtropical Superficial (ASTS), mientras que las mayores contribuciones fueron de Agua Tropical Superficial (ATS). Parámetros como la temperatura y la salinidad determinaron un calentamiento del océano, tanto a nivel superficial como subsuperficial, lo cual sería una consecuencia de los procesos de redistribución de calor del océano.Esta dinámica ocasionaría anomalías del orden de los 30 metros para el caso de la profundidad de la termoclima y 2°C para el caso de la TSM. En el plancton se registraron valores mayores a 5000 larvas de peces/10 m2. La menor cantidad (260 larvas/10 m2) se registró hacia el norte del Golfo, observándose al mismo tiempo... |
Tipo: Journal Contribution |
Palavras-chave: Oceanographic data; Geochemistry; Salinity data; Plankton; Organic matter; Plankton; Organic matter; Geochemistry; Http://aims.fao.org/aos/agrovoc/c_5950; Http://aims.fao.org/aos/agrovoc/c_5387; Http://aims.fao.org/aos/agrovoc/c_24848. |
Ano: 1994 |
URL: http://hdl.handle.net/1834/3080 |
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Toma,Maíra Akemi; Owens,Phillip Ray; Silva,Carlos Alberto; Silva,Sérgio Henrique Godinho; Silva,Elen Alvarenga; Curi,Nilton. |
In soil surveys, it is usual to find profiles with an uncommon disposition of horizons. Dark horizons in depth might be either the consequence of erosion and redeposition of soil materials from upslope or an indication of the podzolization process, which forms a spodic horizon. Few laboratory analyses are known to characterize dark subsurface horizons which could allow for the differentiation of spodic from buried A horizons. Some researchers propose C-humic and C-fulvic acid fraction ratios and forms of carbon to analyze characteristics of these horizons. Therefore, this research aimed to characterize dark subsurface horizons found in soils under a Eucalyptus minimum tillage system in the state of Rio Grande do Sul, Brazil, and to relate soil organic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Humic substances; Organic matter; Erosion; Podzolization; Redeposition. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162015000400334 |
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Leonel,Sarita; Tecchio,Marco Antonio. |
Fertilization using organic compounds is complementary to chemical fertilization, being essential to integrated fruit production. Reports on fig tree (Ficus carica L.) organic fertilization and mineral nutrition are worldwide scarce, especially in Brazil. This experiment aimed to evaluate the effects of cattle manure fertilization on the yield and productivity of the fig tree 'Roxo de Valinhos' in Botucatu, São Paulo State, Brazil, during the 2002/03, 2003/04, 2004/05 and 2005/06 crop cycles. Plants aged one, two, three and four year olds received the following cattle manure treatments: control (no fertilizer), 25%, 50%, 75%, 100%, 125% and 150% of the recommended N level for this crop. The evaluated variables were: fruit number, weight and mean diameter,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Ficus carica L.; Nitrogen; Organic matter. |
Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162009000600013 |
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Carvalho,Arminda Moreira de; Marchão,Robélio Leandro; Bustamante,Mercedes Maria da Cunha; Alcântara,Flávia Aparecida de; Coser,Thais Rodrigues. |
The objective of this study was to investigate the chemical composition of cover crops by solid-state CPMAS 13C NMR spectroscopy and its effects on carbon, nitrogen and phosphorus in a Typic Acrustox. Cover crops (Crotalaria juncea, Canavalia brasiliensis, Cajanus cajan, Mucuna pruriens and Raphanus sativus) and natural fallow were studied in rotation with maize under conventional and no-tillage regimes. Tissues of Crotalaria juncea, Canavalia brasiliensis, Mucuna pruriens and Raphanus sativus were analyzed using CPMAS 13C NMR spectroscopy. Soil samples were collected at the end of the growing season of the cover crops (September 2002) and during the grain filling period in corn from 0-5 and 5-10 cm layers. Cajanus cajan presented the lowest content of... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Brazilian Savanna; Solid-state CPMAS 13C NMR spectroscopy; Organic matter; Ecological Intensification. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902014000500012 |
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Souza,Marcelo Fernando Pereira; Silva,Mariana Pina da; Arf,Orivaldo; Cassiolato,Ana Maria Rodrigues. |
The use of cover crops has been suggested as an effective method to maintain and/or increase the organic matter content, while maintaining and/or enhancing the soil physical, chemical and biological properties. The fertility of Cerrado soils is low and, consequently, phosphorus levels as well. Phosphorus is required at every metabolic stage of the plant, as it plays a role in the processes of protein and energy synthesis and influences the photosynthetic process. This study evaluated the influence of cover crops and phosphorus rates on soil chemical and biological properties after two consecutive years of common bean. The study analyzed an Oxisol in Selvíria (Mato Grosso do Sul, Brazil), in a randomized block, split plot design, in a total of 24 treatments... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Microbial biomass carbon; Microbial activity; Organic matter; Cover plants; Cerrado. |
Ano: 2013 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832013000600006 |
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Bueno,José Rafael Pires; Berton,Ronaldo Severiano; Silveira,Adriana Parada Dias da; Chiba,Marcio Koiti; Andrade,Cristiano Alberto de; Maria,Isabella Clerici De. |
Studies on sewage sludge (SS) have confirmed the possibilities of using this waste as fertilizer and/or soil conditioner in crop production areas. Despite restrictions with regard to the levels of potentially toxic elements (PTE) and pathogens, it is believed that properly treated SS with low PTE levels, applied to soil at adequate rates, may improve the soil chemical and microbiological properties. This study consisted of a long-term field experiment conducted on a Typic Haplorthox (eutroferric Red Latosol) treated with SS for seven successive years for maize production, to evaluate changes in the soil chemical and microbiological properties. The treatments consisted of two SS rates (single and double dose of the crop N requirement) and a mineral... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Municipal waste; Organic matter; Soil microbes; Maize. |
Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832011000400040 |
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ADUAN, R. E.; VILELA, M. de F.; KLINK, C. A.. |
ABSTRACT: In the Cerrado Biome, the internal carbon cycling, the main carbon pools size, and the fluxes intensity between carbon pools are far from to be completely understood. This study presents the main carbon pools and cycling fluxes in terrestrial ecosystems, emphasizing the neotropical savannas. This study will also review literature of internal carbon cycling in the Cerrado. In spite of the science advances, the knowledge of internal carbon dynamics in the Cerrado are scarce. The relation between the carbon pools size and fluxes intensity and the Cerrado's vegetation phytofisionomies, soil gradient, and climate still remains unknown. The carbon pools and fluxes data analysis show that the Cerrado's aerial carbon pools are smaller than the forest... |
Tipo: Documentos (INFOTECA-E) |
Palavras-chave: Fluxo de carbono; Carbon fluxes; Carbon cycling.; Biomassa; Cerrado; Matéria Orgânica; Serapilheira; Solo.; Biomass; Organic matter; Soil.. |
Ano: 2003 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/569012 |
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Registros recuperados: 174 | |
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