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| Registros recuperados: 238 | |
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| Bjorneberg, D.L.; Ippolito, J.A.; Koehn, A.C.. |
| Water, sediment and nutrients flowing into and out of the 82,000 ha Twin Falls,ID irrigation tract were measured from 2005 to 2008. Approximately 80% of the water flowing into the watershed was irrigation water diverted from the Snake River. About 40% of the watershed inflow returned to the Snake River. Much of this return flow was water from subsurface drain tiles and tunnels that drain shallow groundwater. Converting from furrow to sprinkler irrigation, improved irrigation management, and constructed sediment ponds have reduced sediment loss from 460 kg/ha in 1971 to <100 kg/ha in 2005. In 2007 and 2008, more sediment and phosphorus entered the watershed than returned to the Snake River. Diverting irrigation water into the watershed removed 6300 Mg of... |
| Tipo: Conference or Workshop Item |
Palavras-chave: Irrigation control; Runoff losses; Nutrient losses; Nutrients; Soil. |
| Ano: 2013 |
URL: http://eprints.nwisrl.ars.usda.gov/1571/1/1527.pdf |
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| Smith, D.R.; Owens, P.R.; Leytem, A.B.; Warnemuende, E.A.. |
| Nutrient losses to surface waters following fertilization contribute to eutrophication. This study was conducted to compare the impacts of fertilization with inorganic fertilizer, swine (Sus scrofa domesticus) manure or poultry (Gallus domesticus) litter on runoff water quality, and how the duration between application and the first runoff event affects resulting water quality. Fertilizers were applied at 35 kg P ha-1-, and the duration between application and the first runoff event varied between 1 and 29 days. Swine manure was the greatest risk to water quality 1 day after fertilization due to elevated phosphorus (8.4 mg P L -1) and ammonium (10.3 mg NH4-N L-1) concentrations; however, this risk decreased rapidly. Phosphorus concentrations were 2.6... |
| Tipo: Article |
Palavras-chave: Nutrients; Chemistry; Fertilizer; Mass Import - autoclassified (may be erroneous). |
| Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/61/1/1223.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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| Donato,Paulo E. R.; Donato,Sérgio L. R.; Silva,João A.; Pires,Aureliano J. V.; Rosa,Raul C. C.; Aquino,Aureluci A.. |
| ABSTRACT The objective of this study was to evaluate the levels of macronutrients in cladodes and yield of cactus pear, cv. ‘Gigante’, cultivated with different cattle manure doses and plant spacings. The experimental design was randomized blocks in 4 x 3 factorial, with three replicates. The treatments consisted of the combination of four doses of cattle manure (0, 30, 60 and 90 Mg ha-1 year-1) with three spacings (1.00 x 0.50, 2.00 x 0.25 and 3.00 x 1.00 x 0.25 m). The contents of macronutrients and dry matter production of cladodes were assessed 600 days after planting. The plant spacings influenced the contents of nitrogen, potassium, calcium and sulfur in the cladodes of ‘Gigante’ cactus pear and there was interaction between spacing and manure dose... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Opuntia; Plant arrangement; Natural fertilization; Nutrients. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1415-43662016001201083 |
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| Dadalt,Julio Cezar; Ribeiro,Andréa Machado Leal; Kessler,Alexandre de Mello; Wesendonck,William Rui; Bockor,Luciane; Gomes,Gilson Alexandre. |
| The objective of this study was to evaluate nutritional and energetic value of rice by-products, with or without phytase, using growing pigs. Thirty-six male pigs were housed in individual metabolic cages. Total collection of feces and urine was carried out in two periods of ten days: five days for adaptation and five days for collection. A randomized blocks design was used, considering the sampling period as a block, with five treatments and seven replicates. Two control diets (with and without phytase - Phy) were used in the digestibility calculations, the latter in order to evaluate the enzyme influence on energy digestibility of the tested ingredients. The control diet was replaced by 30% of one of the ingredients: defatted rice bran (DRB) with and... |
| Tipo: Info:eu-repo/semantics/other |
Palavras-chave: Alternative ingredients; Dephytinization; Enzyme; Nutrients. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782015000701305 |
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| Gonçalves,José Francisco de C.; Vieira,Gil; Marenco,Ricardo A.; Ferraz,João Baptista S.; Santos Junior,Ulysses Moreira dos; Barros,Francisco Cleber F.. |
| Studies on nutritional status and leaf traits were carried out in two tropical tree species Swietenia macrophylla King (mahogany) and Dipetryx odorata Aubl. Willd. (tonka bean) planted under contrasting light environments in Presidente Figueiredo-AM, Brazil. Leaves of S. macrophylla and D. odorata were collected in three year-old trees grown under full sunlight (about 2000 µmol m-2 s-1) and natural shade under a closed canopy of Balsa-wood plantation (Ochroma pyramidale Cav. Ex. Lam.Urb) about 260 µmol m-2 s-1. The parameters analysed were leaf area (LA), leaf dry mass (LDM), specific leaf area (SLA) and leaf nutrient contents. It was observed that, S. macrophylla leaves grown under full sunlight showed LA 35% lower than those grown under shade. In D.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Tropical species; Leaf traits; Nutrients; Forest succession. |
| Ano: 2005 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0044-59672005000100004 |
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| Richards, Timothy J.; Patterson, Paul M.; Tegene, Abebayehu. |
| Widespread obesity in the U.S. is a relatively recent phenomenon, reaching epidemic proportions only in the last 15 years. However, existing research shows that while calorie expenditure through physical activity has not changed appreciably since 1980, calorie consumption has risen dramatically. Consequently, any explanation of obesity must address the reason why consumers tend to overeat in spite of somewhat obvious future health implications. This study tests for an addiction to food nutrients as a potential explanation for the obesity epidemic. Specifically, we use a random coefficients (mixed) logit model applied to household scanner data to test a multivariate version of the rational addiction model of Becker and Murphy and Chaloupka. We find evidence... |
| Tipo: Working or Discussion Paper |
Palavras-chave: Addiction; Demand; Mixed logit; Nutrients; Obesity.; Food Consumption/Nutrition/Food Safety. |
| Ano: 2004 |
URL: http://purl.umn.edu/28539 |
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| Le Boyer, A.; Cambon, Gildas; Daniault, N.; Herbette, Steven; Le Cann, B.; Marie, Louis; Morin, P.. |
| The Ushant tidal front is the dominant feature of the summer season hydrological structure of the Iroise Sea. It separates tidally mixed coastal waters from thermally stratified open Celtic Sea waters. This article reports on observations made in September 2007 during two short cruises that took place aboard R/V "Cotes de la Manche", and gives a general account of the physical structure of the front along one cross-frontal transect. The data set comprises data from a 4 month ADCP mooring, short CTD/fluorescence/nutrients transects, Lagrangian drifter trajectories, and HF radar surface current measurements. One finding is that the surface and bottom fronts, being affected by different dynamical influences, are not necessarily coincident in the vertical.... |
| Tipo: Text |
Palavras-chave: Nutrients; Drifters; HF radars; Hydrology; Tidal mixing front; Shelf dynamics. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6417.pdf |
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| Aissaoui, A.; Turki, S.; Ben Hassine, O. K.. |
| Afin de fournir une meilleure idée sur la structure et la dynamique de la communauté des dinoflagellés et leurs relations avec les paramètres environnementaux dans les zones semi-fermées en communication avec le golfe de Tunis, une étude a été réalisée dans les ports puniques de Carthage afin d’estimer les densités et la dynamique des espèces de dinoflagellés ainsi que les variations des concentrations en nutriments, de janvier à juin 2006. Un nombre de 66 espèces de dinoflagellés ont été identifiés dont 14 espèces sont connues pour être nocives et responsables d’efflorescences nuisibles alors que 21 espèces sont connues pour être productrices de toxines. L'analyse statistique nous a permis de révéler des corrélations significatives entre les densités de... |
| Tipo: Journal Contribution |
Palavras-chave: Parameters; Nutrients (mineral); Coastal environment; Plankton; Nutrients; Plankton. |
| Ano: 2012 |
URL: http://hdl.handle.net/1834/5318 |
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| Agusti, Susana; Martinez-ayala, Juan; Regaudie-de-gioux, Aurore; Duarte, Carlos M.. |
| Increased oligotrophication is expected for oligotrophic areas as a consequence of ocean warming, which reduces diffusive vertical nutrient supply due to strengthened stratification. Evidence of ocean oligotrophication has been, thus far, reported for the open ocean. Here we reported oligotrophication and associated changes in plankton community metabolism with warming in a pristine, oligotrophic Mediterranean coastal area (Cap Salines, Mallorca Island, Spain) during a 10 years time series. As a temperate area, there were seasonal patterns associated to changes in the broad temperature range (12.0.28.4.C), with a primary phytoplankton bloom in late winter and a secondary one in the fall. Community respiration (R) rates peaked during summers and showed... |
| Tipo: Text |
Palavras-chave: Oligotrophiocation; Mediterranean sea; Respiration; Net community production; Nutrients; Gross primary production; Warming; Chlorophyll. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00419/53091/54048.pdf |
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| Rabalais,Nancy N. |
| The seasonal formation of a bottom-water layer severely depleted in dissolved oxygen has become a perennial occurrence on the Louisiana continental shelf adjacent to the Mississippi River system. Dramatic changes have occurred in this coastal ecosystem in the last half of the 20th century as the loads of dissolved inorganic nitrogen tripled. There are increases in primary production, shifts in phytoplankton community composition, changes in trophic interactions, and worsening severity of hypoxia. The river-influenced continental shelf is representative of similar ecosystems in which increased nutrient flux to the coastal ocean has resulted in eutrophication and subsequently hypoxia. The hypoxic conditions (dissolved oxygen less than 2 mg L-1) cover up to... |
| Tipo: Journal article |
Palavras-chave: Anoxia; Hypoxia; Eutrophication; Nutrients; Nitrogen. |
| Ano: 2006 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382006000300015 |
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| Daniel, Anne; Kerouel, Roger; Aminot, Alain. |
| Following previous work, the production of reference material for nutrients in seawater, using pasteurization as a preservation method, was carried out seven times between 2006 and 2010 in the framework of inter-laboratory exercises. The preparation of samples from natural seawater allowed to become depleted in nutrients then spiked, bottled and pasteurized, is described. Five main nutrients are involved in this study: ammonium, nitrite, nitrate, phosphate and silicate. Bottles are in glass for the ammonium samples and in plastic for the other nutrients. Pasteurization was performed at 80 ± 3 °C for 2 h. Samples were controlled for homogeneity and stability at 3–5 month interval, before and after the period allocated for each exercise and a third time... |
| Tipo: Text |
Palavras-chave: Pasteurization; Nutrients; Seawater; Inter-laboratory exercises. |
| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00058/16905/15066.pdf |
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| Oliveira,Jacineumo F. de; Rodrigues,Fernando N.; Fia,Ronaldo; Vilela,Hévelyn S.; Mafra,Dayana C. B.. |
| ABSTRACT: The aim of this study was to evaluate the performance of Tifton 85 grass cultivated in soil columns and fertilized with different wastewater doses of swine slaughterhouse. The experiment was conducted in the Environmental Engineering Center and Sanitary of UFLA/MG in PVC columns filled with Dark Red Latosol (Oxisol) and randomly distributed. The treatments applied with nitrogen based load (300 kg ha de N years−1) consisted of four doses of SW and AQT0 control at random. Three cuts were performed, at 60, 90 and 120 days after planting. The highest yields were 10.06, 16.82 and 20.39 t ha−1 in AQT0, AAT4 and AAT3 treatments, respectively. With the increase of nutrients by N rates and root development of Tifton 85 grass, we observed higher... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Productivity; Forage; Nutrients; Disposal; Agroindustrial wastewaters. |
| Ano: 2017 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162017000400790 |
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| Registros recuperados: 238 | |
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