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Registros recuperados: 40 | |
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Paparazzo,Flavio E.; Alder,Viviana A.; Schloss,Irene R.; Bianchi,Alejandro; Esteves,Jose L.. |
The Drake Passage (DP) links the Southern Pacific and Atlantic Oceans, and acts as a physical narrowing for the largest current of the World Ocean, the Antarctic Circumpolar Current (ACC). This result in a constriction of the main circumpolar fronts related to the ACC: the Subantarctic Front, the Polar Front, the Southern Antarctic Circumpolar Current Front and the Continental Water Boundary Front. Previous studies showed that the DP is a high-nutrient low-chlorophyll (HNLC) region, but studies on the interannual and seasonal macronutrients' fluctuations in relation with chlorophyll and frontal areas in the DP are scarce. This study analyzes the spatial and temporal trends of nitrate, phosphate, and silicate on surface samples from 113 oceanographic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nitrate; Phosphate; Silicate; Chlorophyll-a; Temperature; Salinity; Antarctic fronts; Antarctic zones; Seasonal variation; Interannual variation. |
Ano: 2016 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1667-782X2016000100004 |
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Alvarez,José M; Pasian,Claudio; Lal,Rattan; López,Rafael; Fernández,Manuel. |
ABSTRACT Containerized ornamental plant production is facing several environmental challenges. One of them is to replace the widely used, but with questionable sustainability, peat based substrates and another is to avoid water contamination by chemicals leaching from the nursery. Therefore, as have been verified that petunia and pelargonium plants can be produced in peat-based growing media partially replaced by vermicompost (V) and biochar (B) without decreasing commercial quality, this study has focused on analyzing the leachate from a standard peat-based substrate as a control, used for producing these two ornamental species, and those from the same substrate to which different proportions in volume of V (10% and 20%) and B (4% and 12%) have been... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Petunia hybrida; Pelargonium peltatum; Peat replacement; Water contamination; Nitrate; Phosphate. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362019000100047 |
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SOARES, W. V.; MACEDO, M. C. M.; VILELA, L.; SOUZA, O. C. de. |
Um experimento no campo foi conduzido num Latossolo Roxo Alico muito argiloso, fase cerradao, em Campo Grande - MS, durante 66 meses (1978- 1984), com os seguintes objetivos: Obter a curva de resposta da Brachiaria decumbens ao fosforo e estimar os niveis criticos de fosforo no solo para o estabecimento e a manutencao de pastagem com essa graminea. Os tratamentos constaram de sete doses de fosforo: 0,40, 80, 160, 320, 640 e 1280kg/ha de P205 como superfosfato triplo, em parcelas de 7x5 m, num delineamento de blocos ao acaso com quatro repeticoes. Dez dias antes da aplicacao dos tratamentos, 2,6t/ha de calcario dolomitico foram incorporadas a 20 cm profundidade. Incluiu-se nos tratamentos adubacao basica constituida de: 50, 20, 50, 5 e 1 kg/ha,... |
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Cultivar Basilisk; Phosphate; Basilisk; Brazilian savannas; Feed grasses; Fertilization; Latosol; Pasture; Phosphorius; Planta gramínea; Red latosol; Savanna.; Adubação; Brachiaria Decumbens; Cerrado; Fósforo; Fosfato; Gramínea Forrageira; Latossolo Roxo; Pastagem; Solo.; Ferralsols; Fertilizer application; Forage; Fertilizers; Phosphorus; Varieties.; Soil. |
Ano: 1999 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/546467 |
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PEREIRA, J. R.; FARIA, C. M. B. de. |
Avaliacao da eficiencia e efeito residual de diversos fosfatos em Latossolo Vermelho Amarelo do submedio Sao Francisco. Constituiu-se de dois experimentos, o primeiro foi avaliada a eficiencia dos seguintes fosfatos na produtividade do milho var. Centralmex: catalao moido, catalao 350, catalao 600, catalao tratado termicamente, patos moidos; patos 250, patos 600, patos tratado termicamente, araxa moido e araxa tratado termicamente. Foi avaliado, tambem, o efeito residual desses fosfatos atraves de dois ciclos da cultura do milho. O segundo expeimento foi realizado com as mesmas caracteristicas do anterior. Como fontes de fosforo foram usados os seguintes produtos: termofosfato goisfertil; fosfato RNC, dapinho, fosfatos parcialmente acidulados fosforico. |
Tipo: Outras publicações técnicas (INFOTECA-E) |
Palavras-chave: Variety; Soils; Fertility; Phosphate; Fertilidade; Fosfato; Milho; Variedade; Solo; Zea Mays; Corn. |
Ano: 1988 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/132825 |
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Menesguen, Alain; Aminot, Alain; Belin, Catherine; Chapelle, Annie; Guillaud, Jean-francois; Joanny, Michel; Lefebvre, Alain; Merceron, Michel; Piriou, Jean-yves; Souchu, Philippe. |
In order to be able to count the cases of coastal eutrophication and to propose methods to monitor as well as to reduce these phenomena, first of all it is necessary to precisely define the word eutrophication itself. Instead of the strict etymological definition, that is to say a progression of the enrichment of a medium, we will rather retain the concept of a state enriched at a point such as it causes harmful effects on the ecosystem, and nuisances to man's activities. Based on the average chemical equations of the organic matter synthesis/degradation in the sea, this operational definition thus puts forwards the harmful consequences of enrichment, i.e. the production of an excessive algal biomass, sometimes unbalanced from the point of view of... |
Tipo: Text |
Palavras-chave: Alexandrium; Phaeocystis; Monostroma; Ulva; Dilution plume; Water trapping; Anoxia; Nitrogen and phosphorus loadings; Red tides; Phytoplankton blooms; Green tides; Eutrophication; Alexandrium; Phaeocystis; Monostroma; Ulva; Panache de dilution; Confinement; Anoxie; Phosphate; Nitrate; Apports terrigènes; Eaux colorées; Blooms phytoplanctoniques; Marées vertes; Eutrophisation. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/rapport-22.pdf |
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Prego, R; Vergara, J. |
Nutrient fluxes to the Bay of Biscay from the Cantabrian basin have been quantified for the first time. Data between 1981 and 1995 of the main 16 Cantabrian rivers from the COCA monitoring programme have been used. Values of water flow and dissolved inorganic nitrogen (DIN), phosphate and silicate concentrations have been taken. Equations are proposed to quantify the fluvial nutrient contributions to the Cantabrian Sea. The annual average of continental outputs to the Bay of Biscay from the Cantabrian basin is 16.1 x 10(9) m(3) of freshwater, 1.0 x 10(9) mol of N in DIN, 0.062 x 10(9) mol of phosphate and 1.2 x 10(9) mol of silicate. In comparison with the French rivers, those of the Cantabrian have small fluxes and their outflow is very disperse, not... |
Tipo: Text |
Palavras-chave: Nitrate; Phosphate; Silicate; Fleuve; Côte Cantabrique; Nitrate; Phosphate; Silicate; River; Cantabrian coast. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00326/43685/43190.pdf |
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Labry, Claire; Delmas, Daniel; Herbland, Alain. |
Previous studies conducted on the continental shelf in the Southeast Bay of Biscay influenced by Gironde waters (one of the two largest rivers on the French Atlantic coast) showed the occurrence of late winter phytoplankton blooms and phosphorus limitation of algal growth thereafter. In this context, the importance of dissolved organic phosphorus (DOP) for both algae and bacteria was investigated in 1998 and 1999 in terms of stocks and fluxes. Within the mixed layer, although phosphate decreased until exhaustion from winter to spring, DOP remained high and phosphate monoesters made up between I I to 65% of this pool. Total alkaline phosphatase activity (APA, V-max) rose gradually from winter (2-8 nM h(-1)) to late spring (100-400 nM h-1), which was mainly... |
Tipo: Text |
Palavras-chave: Phytoplankton; Phosphate; Gironde; DOP; Bacteria; Alkaline phosphatases. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-608.pdf |
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Lema, Anais Kimberley; Latimier, Marie; Nezan, Elisabeth; Fauchot, Juliette; Le Gac, Mickael. |
The factors responsible for inducing the synthesis of toxins and responses from toxic phytoplankton blooms remain unclear. In this study we compare the influence of genotypic (at both the intra and interspecific levels) and environmental factors (nutrient concentration and ratio) on growth (in terms of cell densities) and domoic acid (DA) production in three Pseudo-nitzschia species: P. australis, P.pungens and P.fradulenta. A strong phosphate effect was detected. More precisely, a low initial concentration in phosphate, even at high initial nitrogen and silicate concentrations, induced the highest DA concentrations and the lowest cell densities in all strains/species studied. In contrast, a low initial concentration of nitrogen and silicate combined, with... |
Tipo: Text |
Palavras-chave: Pseudo-nitzschia strains; Domoic acid; Ratio; Phosphate; Nitrogen. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00377/48849/49397.pdf |
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Qui-minet, Zujaila Nohemy; Coudret, Jérôme; Davoult, Dominique; Grall, Jacques; Mendez‐sandin, Miguel; Cariou, Thierry; Martin, Sophie. |
Made up of calcareous coralline algae, maerl beds play a major role as ecosystem engineers in coastal areas throughout the world. They undergo strong anthropogenic pressures, which may threaten their survival. The aim of this study was to gain insight into the future of maerl beds in the context of global and local changes. We examined the effects of rising temperatures (+3°C) and ocean acidification (−0.3 pH units) according to temperature and pH projections (i.e., the RCP 8.5 scenario), and nutrient (N and P) availability on three temperate maerl species (Lithothamnion corallioides, Phymatolithon calcareum, and Lithophyllum incrustans) in the laboratory in winter and summer conditions. Physiological rates of primary production, respiration, and... |
Tipo: Text |
Palavras-chave: Calcification; Maerl; Nitrate; Ocean acidification; Ocean warming; Phosphate; Photosynthesis; Respiration. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00595/70722/68955.pdf |
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Registros recuperados: 40 | |
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