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| Registros recuperados: 74 | |
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| GINOCCHIO,ROSANNA; BAKER,ALAN J.M.. |
| In Latin America, metallic ores are abundant and diverse. However, few metal-tolerant and metal hyperaccumulator plants have been reported in the region in comparison with other areas of the world. This may be largely explained by the scarcity of scientific studies of the native vegetation growing on natural mineralized or metal-contaminated areas and the unfrequent use of biogeochemical prospecting techniques by the local mining industry, rather than the proven absence of these plants. Latin America is, however, an area where metal-tolerant and hyperaccumulator plants (metallophytes) should be found, not only because of the wealth of ore deposits and associated metal polluted areas, but also due to its high and unique plant diversity. If plant formations... |
| Tipo: Journal article |
Palavras-chave: Hyperaccumulators; Metal-tolerant plants; Biodiversity; Metal ores; Biogeochemistry. |
| Ano: 2004 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2004000100014 |
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| MACDONELL,SHELLEY A; FITZSIMONS,SEAN J. |
| Cryoconite holes are water-filled depressions that form on glacier surfaces when uneven distributions of sediment cause differential melting to occur. Cryoconite holes are important features of cold glacier systems, as they enhance meltwater generation, enable the development of complex drainage networks and facilitate the growth of microbial communities on the glacier surface. This paper describes the development of a cryoconite hole hydrological network on an Antarctic glacier, and explores the implications for nutrient storage and delivery within the glacier system. Field measurements included measuring the internal dimensions and repeat mapping of cryoconite holes across the glacier surface, and laboratory analysis included cation and anion analysis on... |
| Tipo: Journal article |
Palavras-chave: Biogeochemistry; Drainage system; Glacier hydrology; Meltwater; Solute. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0716-078X2012000400003 |
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| FIGUEIREDO, R. de O.; OVALLE, A. R. C.; REZENDE, C. E. de; MARTINELLI, L. A.. |
| Abstract: The study was conducted in the lower basin of the Paraíba do Sul River (PSR), in which 57,000 km2 of the basin is located in the Brazilian states of São Paulo, Minas Gerais and Rio de Janeiro. We proposed to identify the main sources of C and N fluxes in the PSR waters, to evaluate biogeochemical processes in the watershed, and to estimate C and N riverine loads to the Atlantic Ocean in the context of the sugarcane plantation expansion for ethanol production. Riverine water samples were collected at seven stations along 12 months. Physicochemical and limnological parameters, as well as discharge, were measured together with organic and inorganic C and N species in the dissolved and suspended particulate material. C and N concentrations in bed... |
| Tipo: Artigo de periódico |
Palavras-chave: Biogeoquímica; Cargas fluviais; Impactos antrópicos; Watershed.; Carbono; Nitrogênio; Agricultura; Impacto ambiental; Bacia hidrográfica; Biogeochemistry; Environmental impact.. |
| Ano: 2011 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/899035 |
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| KAO, R. H.; GIBSON, C. M.; GALLERY, R. E.; MEIER, C. L.; BARNETT, D. T.; DOCHERTY, K. M.; BLEVINS, K. K.; TRAVERS, P. D.; AZUAJE, E.; SPRINGER, Y. P.; THIBAULT, K. M.; MCKENZIE, V. J.; KELLER, M.; ALVES, L. F.; HINCKLEY, E-L. S.; PARNELL, J.; SCHIMEL, D.. |
| Rapid changes in climate and land use and the resulting shifts in species distributions and ecosystem functions have motivated the development of the National Ecological Observatory Network (NEON). Integrating across spatial scales from ground sampling to remote sensing, NEON will provide data for users to address ecological responses to changes in climate, land use, and species invasion across the United States for at least 30 years. Although NEON remote sensing and tower sensor elements are relatively well known, the biological measurements are not. This manuscript describes NEON terrestrial sampling, which targets organisms across a range of generation and turnover times, and a hierarchy of measurable biological states. Measurements encompass species... |
| Tipo: Artigo de periódico |
Palavras-chave: Disease; Abundance; Ecohydrology; Long-term monitoring; National Ecological Observatory Network; Open-access data.; Biodiversity; Biogeochemistry; Demography; Phenology.. |
| Ano: 2013 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/958227 |
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| FERREIRA, A. M. de S. D.; OLIVEIRA, F. de A.; VASCONCELOS, S. S.; GUIMARÃES, J. R. da S.; TOSTES, L. de C. L.; CRUZ JUNIOR, F. O.; FREITAS, J. da L.; COSTA, J. V. T. A.; LOBATO, A. M. B.; SANTOS, A. C. dos. |
| This study was part of the Manipulation of Moisture and Nutrient Availability in Young Regrowth Forests in Eastern Amazonia Project (MANFLORA). The experiment was designed in completely randomized blocks containing control and irrigated treatments during the dry period (5 mm of water/day), with four repetitions each. The monthly mean litter values ranged from 316.10 to 997.90 kg ha-1 month-1. The magnitude of this phenomenon can be explained by the functional role of the floristic structure, represented by the species Myrcia sylvatica (G. mey) DC., Myrcia bracteata (Rich) DC., Miconia ciliata (Rich) DC., Lacistema pubescens Mart., Lacistema aggregatum (Berg.) Rusby, Vismia guianensis (Aubl.) Choisy, Cupania scrobiculata Rich. and Ocotea guianensis Aubl.,... |
| Tipo: Artigo de periódico |
Palavras-chave: Cálcio; Magnésio; Biogeochemistry; Irrigation; Secondary forests. |
| Ano: 2021 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1159130 |
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| FIGUEIREDO, R. de O.; CAK, A.; MARKEWITZ, D.. |
| Abstract: Expansion of agriculture in the Brazilian Amazon has been driven not just by demands from traditional, rural producers, but also large agriculture and cattle producers, both of whom have put considerable pressure on remaining forests and their watersheds. Monitoring of these watersheds has been a focus of intensive study for the past 20 years and although this work has greatly increased our understanding, considerable gaps still remain in our ability to provide adequate recommendations for land management and associated public policies. In this study we present a summary of findings from these previous results. For small properties, the use of fire to prepare land for cultivation remains controversial, while in large properties, forest conversion... |
| Tipo: Artigo de periódico |
Palavras-chave: Uso da Terra; Recurso Hídrico; Floresta Tropical Úmida; Desmatamento; Biogeochemistry; Deforestation; Land management; Land use change; Public policy; Water resources; Watersheds. |
| Ano: 2020 |
URL: http://www.alice.cnptia.embrapa.br/alice/handle/doc/1123149 |
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| Santos,Isaac Rodrigues; Costa,Ronaldo Cataldo; Freitas,Ubiratan; Fillmann,Gilberto. |
| The hypothesis that effluents treated through activated sludge process cause changes in nutrient biogeochemistry of receiving water bodies was investigated in Vieira creek, southern Brazil. Dissolved oxygen, suspended matter, and pH did not vary among the sampling stations. Nutrient, biochemical oxygen demand, and conductivity values were significantly higher downstream from the Wastewater Treatment Plant (WWTP) effluents. Further downstream, nitrate concentrations were higher due to ammonium nitrification, organic matter remineralization and/or the occurrence of unidentified sources. Per capita nutrient emission factors were estimated to be 0.16 kg P.yr-1 and 4.14 kg N.yr-1. Under pristine conditions, low N:P ratios were observed, which were significantly... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Activated sludge; Nutrients; Contamination; Coastal zone; Biogeochemistry; Eutrophication. |
| Ano: 2008 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000100019 |
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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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| PARRON, L. M.; BUSTAMANTE, M. M. da C.; PRADO, C. L. C.. |
| RESUMO: Em função do gradiente de umidade na topografia do terreno e de diferenças entre estações seca e chuvosa, o presente trabalho teve como objetivos quantificar a produção anual e a disponibilidade de nutrientes (N, P, K, Ca, Mg E S) na serapilheira e estimar a eficiência do uso de nutrientes em uma Mata de Galeria. O experimento foi estabelecido numa área de 100 x 100 m da Mata de Galeria do Córrego Pitoco, na Reserva Ecológica do IBGE, DF (15°56'41"S e 47°56'07"W). Como delineamento experimental, foram estabelecidas três linhas de amostragem paralelas ao córrego, distantes 45 m entre si, denominadas, respectivamente, comunidades úmida (na margem do córrego), intermediárias e seca (adjacentes a uma área de Cerrado Típico). A produção de serapilheira... |
| Tipo: Folhetos |
Palavras-chave: Biogeoquímica; Ciclagem de nutriente; Eficiência de nutriente; Savana; Productivity; Nutrient cycling; Litterfall; Nutrient efficiency; Disponibilidade de Nutriente; Floresta Tropical; Produtividade; Biogeochemistry; Savannas; Tropical forests. |
| Ano: 2004 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/569203 |
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| Verdy, A.; Mazloff, M. R.. |
| A Biogeochemical Southern Ocean State Estimate (B-SOSE) is introduced that includes carbon and oxygen fields as well as nutrient cycles. The state estimate is constrained with observations while maintaining closed budgets and obeying dynamical and thermodynamic balances. Observations from profiling floats, shipboard data, underway measurements, and satellites are used for assimilation. The years 2008-2012 are chosen due to the relative abundance of oxygen observations from Argo floats during this time. The skill of the state estimate at fitting the data is assessed. The agreement is best for fields that are constrained with the most observations, such as surface pCO(2) in Drake Passage (44% of the variance captured) and oxygen profiles (over 60% of the... |
| Tipo: Text |
Palavras-chave: Southern Ocean; State estimation; Biogeochemistry. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00662/77394/78995.pdf |
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| Le Traon, Pierre-yves; D'Ortenzio, Fabrizio; Babin, Marcel; Leymarie, Edouard; Marec, Claudie; Pouliquen, Sylvie; Thierry, Virginie; Cabanes, Cecile; Claustre, Hervé; Desbruyeres, Damien; Lacour, Leo; Lagunas, Jose-luis; Maze, Guillaume; Mercier, Herle; Penkerc'H, Christophe; Poffa, Noe; Poteau, Antoine; Prieur, Louis; Racape, Virginie; Randelhoff, Achim; Rehm, Eric; Schmechtig, Catherine Marie; Taillandier, Vincent; Wagener, Thibaut; Xing, Xiaogang. |
| Argo, the international array of profiling floats, is a major component of the global ocean and climate observing system. In 2010, the NAOS (Novel Argo Observing System) project was selected as part of the French “Investissements d’Avenir” Equipex program. The objectives of NAOS were to consolidate the French contribution to Argo’s core mission (global temperature and salinity measurements down to 2000 m), and also to develop the future generation of French Argo profiling floats and prepare the next phase of the Argo program with an extension to the deep ocean (Deep Argo), biogeochemistry (BGC-Argo) and polar seas. This paper summarizes how NAOS has met its objectives. The project significantly boosted France’s contribution to Argo’s core mission by... |
| Tipo: Text |
Palavras-chave: Profiling floats; Deep ocean; Biogeochemistry; Mediterranean Sea; Arctic; Atlantic; Argo. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00654/76584/77729.pdf |
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| Peguero, Guille; Sardans, Jordi; Asensio, Dolores; Fernández-martínez, Marcos; Gargallo-garriga, Albert; Grau, Oriol; Llusià, Joan; Margalef, Olga; Márquez, Laura; Ogaya, Romà; Urbina, Ifigenia; Courtois, Elodie A.; Stahl, Clément; Van Langenhove, Leandro; Verryckt, Lore T.; Richter, Andreas; Janssens, Ivan A.; Peñuelas, Josep. |
| Soil fauna is a key control of the decomposition rate of leaf litter, yet its interactions with litter quality and the soil environment remain elusive. We conducted a litter decomposition experiment across different topographic levels within the landscape replicated in two rainforest sites providing natural gradients in soil fertility to test the hypothesis that low nutrient availability in litter and soil increases the strength of fauna control over litter decomposition. We crossed these data with a large dataset of 44 variables characterizing the biotic and abiotic microenvironment of each sampling point and found that microbe-driven carbon (C) and nitrogen (N) losses from leaf litter were 10.1 and 17.9% lower, respectively, in the nutrient-poorest site,... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Extracellular enzyme activity; Litter decomposition; Nutrients; Soil fauna. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00513/62424/69469.pdf |
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| Registros recuperados: 74 | |
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