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Registros recuperados: 238 | |
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Ippolito, J.A.; Stromberger, M.E.; Lentz, R.D.; Dungan, R.S.. |
The effects of biochar application to calcareous soils are not well documented. In a laboratory incubation study, a hardwood-based, fast pyrolysis biochar was applied (0, 1, 2, and 10% by weight) to a calcareous soil. Changes in soil chemistry, water content, microbial respiration, and microbial community structure were monitored over a 12-month period. Increasing biochar application rate increased the water holding capacity of the soil-biochar blend, a trait that could be beneficial under water limited situations. Biochar application also caused an increase in plant-available iron and manganese, soil carbon content, soil respiration rates, bacterial populations, and a decrease in soil nitrate-nitrogen concentration. Biochar rates of 2 and 10% altered the... |
Tipo: Article |
Palavras-chave: Calcareous soil; Nitrogen; Nutrients. |
Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1532/1/1490.pdf |
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Oliveira,Vanessa de Souza; Lima,Augusto Miguel Nascimento; Salviano,Alessandra Monteiro; Bassoi,Luís Henrique; Pereira,Giuliano Elias. |
Soils under natural conditions have heavy metals in variable concentrations and there may be an increase in these elements as a result of the agricultural practices adopted. Transport of heavy metals in soil mainly occurs in forms dissolved in the soil solution or associated with solid particles, water being their main means of transport. In this context, the aim of this study was to evaluate the heavy metal and micronutrient content in the soil and in the grapevine plant and fruit under different irrigation strategies. The experiment was carried out in Petrolina, PE, Brazil. The treatments consisted of three irrigation strategies: full irrigation (FI), regulated deficit irrigation (RDI), and deficit irrigation (DI). During the period of grape maturation,... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Water availability; Nutrients; Grape. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000100162 |
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Koening,Maria Luise; Macêdo,Silvio José de. |
Quali-quantitative studies and hydrologic parameters were carried out in the profiles 6 (Orange) and 7 (Catuama) during the Victor Hensen cruise, in accordance with the bilateral scientific cooperation agreement Brazil/Germany. Hydrologically a zone of thermic and saline stability characterizes the superficial layer. The nutrient concentrations were generally low on the surface and higher at levels surpassing 100m in depth. 102 taxa were identified including diatoms (49), dinoflagellates (49), bluegreen algae (3), and euglenophyceae (1). The diversity and evenness were high, surpassing the environmental equilibrium. The clustering of samples showed evidence of 2 main groups, one encompassing the stations 32 and 38, characterized predominantly by... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Hydrology; Nutrients; Phytoplankton structure. |
Ano: 1999 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89131999000400002 |
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Ben Othman, Hiba; Pringault, Olivier; Louati, Hela; Hlaili, Asma Sakka; Leboulanger, Christophe. |
Effects of sediment-released contaminants and nitrogen were assessed on phytoplankton communities sampled from Thau lagoon (France, Mediterranean Sea) and one close offshore marine station. Phytoplankton was exposed to sediment elutriate (seawater containing a mix of metals, organic chemicals, and nutrients) or to ammonium enrichment for four days using immersed microcosms exposed to natural conditions of light and temperature. Functional (production - respiration balance) and structural (taxonomy and cell densities) responses of the phytoplankton community were assessed. In the lagoon, both treatments stimulated phytoplankton growth, compare to controls. Conversely in the offshore station, the phytoplankton growth was stimulated only with the sediment... |
Tipo: Text |
Palavras-chave: Sediment resuspension; Mediterranean lagoon; Contaminants; Nutrients; Phytoplankton community. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00352/46364/46317.pdf |
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Marques Júnior,Aguinaldo Nepomuceno; Crapez,Mirian Araujo Carlos; Barboza,Conceição Denise Nunes. |
The present study aimed to evaluate the water quality of the Icaraí Sewage Outfall (ISEO) area. Sampling was conducted during winter and summer, and water samples were analyzed for dissolved oxygen, pH, temperature, salinity, dissolved inorganic nutrients (DIN), seston, particulate organic matter (POM), and pigments. Results showed that the water chemistry of the area suffers temporal and spatial variation. Great variability was also seen in the C:N:P ratios of POM (August, 112:30:1; December, 59:11:1) and in the DIN concentrations. Chlorophyll-a and ammonium concentrations (4.5 µg L-1 - 71.2 µg L-1, and 0.20 µM - 52,6 µM, respectively) characterized the ISEO area as eutrophic. The dispersal of the material was not effective under certain oceanographic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Eutrophication; Sewage outfall; Water pollution; Nutrients; Guanabara Bay. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132006000500014 |
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Merceron, Michel; Antoine, Virginie; Auby, Isabelle; Morand, P. |
Ulva spp., the algae most responsible for green tides in Brittany (France), are found on the foreshore and in the most beachward wave area (MBWA) of many bays during green tide phenomena. These algae have recently been seen drifting at greater depths (reaching -20 m). In view of the significant quantities of algae found at these depths, and the less favorable conditions for algal growth than in the intertidal zone, we attempted to determine if they could grow there. For that, during their maximum growth period (from May to July), algae were picked up at three stations located on the foreshore, in the MBWA and in the subtidal (deep) zones of the Bay of Douarnenez, and their nitrogen, carbon and chlorophyll a+b contents were determined, and their... |
Tipo: Text |
Palavras-chave: Nutrients; Irradiance; Photosynthesis; Ulva sp.; Algal blooms; Eutrophication. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3527.pdf |
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Mazouni, Nabila; Deslous-paoli, Jean-marc; Landrein, Sonia. |
The impact of suspended oyster culture (Crassostrea gigas, Thunberg) on oxygen and nutrient fluxes has been studied in situ, in a coastal lagoon (Thau, France), during a seasonal cycle. On the first plan of the multiple factorial correspondences analysis (MCA), seasons were well discriminated. The fluxes were maximum in summer and minimum in winter. However, this seasonal pattern was not only linked to the water temperature, as autumn and spring (similar temperatures of about 12 degrees C) were distinct in the second factorial plan (2.3). Oxygen uptake by the oyster cultures varied between 0 mu mol m(-2) h(-1) (January) and 11 823 +/- 377 mu mol m(-2) h(-1) (July). Ammonia and nitrate-nitrites were released into the water column respectively at a rate of... |
Tipo: Text |
Palavras-chave: Oxygen; Nutrients; Fluxes; Oyster culture; Oxygène; Nutriments; Flux; Elevage ostréicole. |
Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/1998/publication-840.pdf |
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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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Tedetti, Marc; Bigot, Lionel; Turquet, Jean; Guigue, Catherine; Ferretto, Nicolas; Goutx, Madeleine; Cuet, Pascale. |
We investigated the influence of freshwater discharges on biogeochemistry and benthic communities of La Saline fringing reef, the largest coral reef system of La Réunion Island (France, Indian Ocean). Sampling was conducted in February–March 2012 along a land-ocean continuum, including rivers, groundwater, reef waters, and oceanic waters. Our results indicated the discharges of basalt groundwater (enriched in nitrates) in the southern part of the reef, and the discharges of sand groundwater and river waters (enriched in organic matter) in sites located northward. These discharges mainly impacted fore reef surface waters, while groundwater resurgences were more diffuse and not clearly detected in depth. We highlighted the relationship Si(OH)4/NO3– to... |
Tipo: Text |
Palavras-chave: Coral reefs; La Reunion; Indian Ocean; Eutrophication; Groundwater; Nutrients; Organic matter; Fluorescence. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00658/77030/78316.pdf |
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Lema, Anais Kimberley; Metegnier, Gabriel; Quéré, Julien; Latimier, Marie; Youenou, Agnes; Lambert, Christophe; Fauchot, Juliette; Le Gac, Mickael. |
Untangling the functional basis of divergence between closely related species is a step towards understanding species dynamics within communities at both the evolutionary and ecological scales. We investigated cellular (i.e: growth, domoic acid production, nutrient consumption) and molecular (transcriptomic analyses) responses to varying nutrient concentrations across several strains belonging to three species of the toxic diatom genus Pseudo-nitzschia. Three main results were obtained. First, strains from the same species displayed similar transcriptomic, but not necessarily cellular, responses to the experimental conditions. It showed the importance of considering intra-specific diversity to investigate functional divergence between species. Second, a... |
Tipo: Text |
Palavras-chave: Phenotype; Transcriptomics; Pseudo-nitzschia; Divergence; Nutrients. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00482/59392/62157.pdf |
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Aminot, Alain; Guillaud, Jean-francois; Kerouel, Roger. |
The data of hydrology, nutrients and chlorophyll obtained in the Bay of Seine over the period 1978-1994, from 14 océanographie cruises, are synthetised and illustrated by an atlas. The Bay is a typical example of a coastal area influenced by a large river. In winter, the nutrient input is drained off into the eastern Channel. In spring, nutrients are consumed intensively. Silicate is the first that drops to limiting levels. The spring bloom generally begins in the centre-east of the Bay. Chlorophyll a can reach up to 40-70 µg/l during the year, values typical of eutrophic coastal areas. Despite the regular increase of nitrogen inputs, the biomass (as chlorophyll) has not significantly changed over a fifteen year period. |
Tipo: Text |
Palavras-chave: Chlorophyll; Nutrients; Hydrology; Bay of Seine; Chlorophylle; Nutriments; Hydrologie; Baie de Seine. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/1997/rapport-1428.pdf |
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Maurice, Laurence. |
The main problem of the Girond estuary is a pollution by the cadmium. During this last ten years, the good quality of the water is proved by the analysis of the main physico - chemical and biochemical parameters and bacteria. But since 1989, straight to the Blayais power station, the BOD5 varied between 2 and 3,5 mg.l-1 and a diminution of the dissolved oxygen has been observed; it's probably caused by the accumulation of biodegradable organic matter in the maximum turbidity zone during years characterized by low river flows. For average river flow, urban discharges takes part for 20 % in total fluxes of BD05; in 1991, this part attempts 35 %. During the last 7 years, the pluriannual evolution of the nitrate concentrations measured in the Garonne river... |
Tipo: Text |
Palavras-chave: Oxygène; Sels nutritifs; Matière organique; Bactéries; Apports; Estuaire Gironde; Oxygen; Nutrients; Organic matter; Bacteria; Fluxes; Gironde estuary. |
Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00037/14855/12178.pdf |
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Ciotta,Marlise Nara; Ceretta,Carlos Alberto; Tagliavini,Massimo; Zanotelli,Damiano; Moser,Damiano; Nava,Gilberto; Porro,Duilio; Brunetto,Gustavo. |
Irrigating vineyard soils can affect grapevine water potential, nutritional status, and must composition. This study aimed to evaluate leaf water potential, nutritional status, and must composition in cv. 'Pinot Nero' grapevines grown with and without irrigation. The experiment was conducted at a commercial vineyard of 'Pinot Nero' 828 grafted on SO4rootstock, established in 2002 in Trento, Northern Italy. The treatments were irrigated (I) and non-irrigated (NI) throughout the 2013 crop season. The criteria evaluated were the water potential of the leaves, total nutrient content in the leaves and berries, and weight of 100 berries, as well as the total soluble solids content, pH, and total titratable acidity of the must. Despite providing a less negative... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Nutrients; Irrigation; Vitis vinifera.. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782015000801408 |
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Registros recuperados: 238 | |
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