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Registros recuperados: 45 | |
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Antúnez Ocampo, Oscar Martín. |
Con el objetivo de evaluar la respuesta morfológica, rendimiento y calidad de fruto de Physalis peruviana L., derivadas de semilla y rebrote a la aplicación simultánea de NO3-y NH4+ se llevó a cabo un estudio en invernadero del Colegio de Postgraduados, Campus Montecillo, estado de México. Se utilizaron plantas propagadas por rebrote de plantas de 2 años de edad y por otra parte se utilizaron plantas nuevas obtenidas de semilla. Los tratamientos consistieron de 3 relaciones NO3-/NH4+ (%): 100:0, 75:25 y 50:50, las cuales se distribuyeron en un diseño experimental completamente al azar. Las plantas de rebrote se clasificaron por vigor: alto, medio y bajo. La unidad experimental consistió en una planta colocada en una bolsa negra de polietileno de 19 L con... |
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Palavras-chave: Vigor; Relación nitrato/amonio; Amonio; Rendimiento; Calidad; Relation nitrate/ammonium; Ammonium; Yield; Quality; Edafología; Maestría. |
Ano: 2013 |
URL: http://hdl.handle.net/10521/2151 |
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Campos García, Tonatiu. |
El objetivo de la presente investigación fue estudiar el efecto de las relaciones (en la solución nutritiva) amonio/nitrato (NH4+/NO3-) y calcio/potasio (Ca2+/K+) en plantas de fresa Fragaria x ananassa cv. Festival, cultivadas en fibra de coco en un sistema hidropónico. Los tratamientos de NH4+/NO3- fueron 100/0, 75/25, 25/75 y 0/100 en porcentaje de nitrógeno total y 58/42, 75/25, 50/50, 25/75 de Ca2+/K+. Los resultados obtenidos indicaron que las plantas con mayor crecimiento vegetativo y área foliar fueron las que se cultivaron con el tratamiento 100/0 donde se adicionó el 100% de nitrógeno en forma de amonio. También se observó que la corona es el órgano de la planta que concentra la mayor cantidad de NH4+ y NO3-. La concentración de azúcares y... |
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Palavras-chave: Fresa; Amonio; Nitrato; Relaciones; Producción; Strawberry; Ammonium; Nitrate; Ratio; Yield; Edafología; Maestría. |
Ano: 2014 |
URL: http://hdl.handle.net/10521/2306 |
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Vargas,Gustavo; Donoso-Bravo,Andrés; Vergara,Christian; Ruiz-Filippi,Gonzalo. |
Background: Industrial wastewaters with a high content of nitrogen are a relevant environmental problem. Currently, treatments to remove nitrogen are not efficient, so is necessary to develop alternative methods. The objective of this study is to investigate a consortium of microalgae - nitrifying, that due to the symbiosis between them could be an interesting alternative. Results: In this study, it was possible to obtain a consortium of nitrifying bacteria (NB) and microalgae (MA) capable of operating with low requirements of dissolved oxygen, using aerobic sludge from wastewater treatment plants. During the operation, this consortium presents removal percentages above 98% of ammonia, even at concentrations of DO of 0.5 mg O2 L-1. It is estimated that the... |
Tipo: Journal article |
Palavras-chave: Ammonium; Consortium nitrifying-microalgae; Oxygen; Respirometry. |
Ano: 2016 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582016000500007 |
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Staelens,Jeroen; Godoy,Roberto; Oyarzún,Carlos; Thibo,Karen; Verheyen,Kris. |
Nitrogen return by leaf litterfall was compared with atmospheric nitrogen deposition for two deciduous Nothofagus stands in southern Chile, located in areas with contrasting land use. The litterfall return of nitrogen in a Nothofagus alpina (Poepp. et Endl.) Oerst. stand at San Pablo de Tregua, in the Cordillera de los Andes, was similar to the litterfall return in a Nothofagus obliqua (Mirb.) Oerst. stand at Paillaco, in the Central Depression. In contrast, the net throughfall and stemflow deposition differed significantly between the two stands. At San Pablo de Tregua, the annual bulk deposition of NH4+ and NO3- was significantly higher than the throughfall and stemflow deposition reaching the forest floor. This demonstrates an uptake of inorganic... |
Tipo: Journal article |
Palavras-chave: Ammonium; Atmospheric deposition; Canopy interactions; Nitrate; Nutrient cycling; Amonio; Ciclos de nutrientes; Depositación atmosférica; Interacciones del dosel; Nitrato. |
Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200002 |
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Oyarzún,Carlos; Godoy,Roberto; Staelens,Jeroen; Aracena,Claudia; Proschle,Juan. |
Forest structure and tree species can have a significant impact on total atmospheric nitrogen (N) deposition; for example, deciduous forests have higher N requirements than coniferous forests. However, knowledge about the effect of the conversion of native Chilean vegetation cover by exotic plantations on N cycling is scarce. The aim of this study was to determine the effect of the replacement of a Nothofagus obliqua native forest by a Pinus radiata plantation in southern Chile on the chemistry of throughfall, stemflow, soil water infiltration and percolation. Pinus radiata stemflow was more acidic (pH 4.7) than precipitation (pH 5.2) and throughfall (pH 5.6), while in the Nothofagus forest stemflow and throughfall pH were 6.3 and 6.1, respectively. In the... |
Tipo: Journal article |
Palavras-chave: Ammonium; Infiltration; Nitrate; Soil percolation; Throughfall. |
Ano: 2005 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-66432005000200004 |
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Andriolo,Jerônimo L; Godoi,Rodrigo dos S; Cogo,Clarissa M; Bortolotto,Orcial C; Luz,Gean L da; Madaloz,José Carlos. |
Lettuce plants, cv. Vera, were grown at five NH4+:NO3- ratios in the nutrient solution in a 0.15 m deep sand growing bed. A standard nutrient solution was used, with the composition of, in mmol L-1, 11.0 NO3-; 1.5 H2PO4-; 6.5 SO4--; 7.5 Ca++; 10.0 K+ and 1.5 Mg++, and, in mg L-1, 0.42 Mn; 0.26 Zn; 0.05 Cu; 0.50 B; 0.04 Mo, and 4.82 chelate Fe. Ammonium nitrate was used to supply NH4+ concentrations of 2.5; 5; 7.5 and 10 mmol L-1, reaching NH4+:NO3- ratios of 0:11 (T1); 2.5:13.5 (T2); 5:16 (T3); 7.5:18.5 (T4) and 10:21 mmol L-1 (T5) as treatments. A completely randomized experimental design was used, with four replications and 20 plants per plot. Four plants of each plot were harvested at 25 days after planting, to determine shoot and root dry mass, shoot... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Lactuca sativa; Fertigation; Hydroponics; Ammonium. |
Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-05362006000300016 |
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Трусевич, В. В.; Столбов, А. Я.; Вялова, О. Ю.; Кондратьева, Т. П.; Морозова, А. Л.; Шульман, Г. Е.. |
Исследованы особенности потребления кислорода и экскреции азота, а также их соотношение у мидий естественных поселений из районов чистой воды и хронического воздействия бытовых стоков. У моллюсков из биотопа загрязненной воды наблюдается пониженный уровень метаболизма. В условиях кратковременной аутогенной гипоксии критические уровни насыщения воды кислородом, лимитирующие обмен у моллюсков, проявляются при более низких величинах, по сравнению с мидиями из биотопов чистой воды. Ведущая роль в энергообеспечении метаболизма мидий из биотопа загрязненной воды принадлежит белково-азотистым субстратам, что свидетельствует об их меньшей устойчивости к воздействию неблагоприятных факторов. Скорость потребления кислорода и экскреции азота и их соотношение О/N... |
Tipo: Journal Contribution |
Palavras-chave: Экофизиология; Мидии; Загрязнение; Дыхание; Аммоний; Соотношение O/N; Ecophysiology; Mytilus; Sewage; Respiration; Ammonium; O/N ratio Anaerobic respiration Sewage Ecophysiology Sewage http://aims.fao.org/aos/agrovoc/c_7007. |
Ano: 2004 |
URL: http://repository.ibss.org.ua/dspace/handle/99011/71 |
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ANDRADE, S. R. M.; SANT'ANNA, J.; MOSQUIM, P. R.. |
O objetivo deste trabalho foi estudar os efeitos da nutricao nitrica e amoniacal na distribuicao de nitrato e na atividade in vitro da redutase do nitrato em plantas de capim coloniao ( Panicum maximum Jacq.). as plantas receberam 7 mM de nitrogenio nas forma N- NH4 +, N-NO3- ou combinadas nas seguintes proporcoes 0/100, 25/75, 50/50, 75/25 e 100/0. A extracao enzigmatica foi feita em Tris-HCI 50mM pH 7,5, EDTA 0,5 mM e b-mercaptoetanol 10mM, e para o ensaio utilizou-se 200 mmoles de Tris-HCI pH 7,5, 20 mmoles KNO3, 0,1 mmol NADH e 0,1 mL de Triton X-100 1% no volume final de 2,0 mL. A concentracao de nitrato foi levemente superior na parte aerea quando as plantas receberam ambas as formas de nitrogenio, e na raiz seta decresceu com o aumento da proporcao... |
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Assimilacao de nitrogenio; Amonio; Nitrogen assimilation; Nitrate; Ammonium; Fisiologia vegetal: Nutricao mineral.; Capim Colonião; Cerrado; Fisiologia Vegetal; Nitrogênio; Nitrato; Panicum Maximum.; Plant physiology.. |
Ano: 2001 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/567071 |
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ANDRADE, S. R. M.; SANT'ANNA, R.; MOSQUIM, P. R.; CAMBRAIA, J.. |
Visando a elucidar alguns aspectos do metabolismo do nitrogenio por plantas de Panicum maximum, estudaram-se os efeitos da proporcao NH +4/NO-3 na variacao do pH das solucoes nutritivas de tratamento, no acumulo de materia seca e na distribuicaoo de nitrogenio na planta. Para tal, as plantas foram cultivadas em camara de crescimento na solucao nutritiva (pH 5,5) completa, contendo nitrogenio somente na forma nitrica. Aos 25 dias depois da germinacao, as plantas foram submetidas a 100 ppm de nitrogenio fornecido nas formas nitrica e amoniacal ou amonical, nas seguintes proporcoes 0/100,25/75,50/50,75/25 e 100/0, durante quatro dias. O pH das solucoes nutritivas foi medido e corrigido diariamente. Os resultados demostraram que o pH aumentou na presenca... |
Tipo: Boletim de Pesquisa e Desenvolvimento (INFOTECA-E) |
Palavras-chave: Amonio; Absorcao de nitrogenio; Nitrogen uptake; Ammonium; Nitrate; Fisiologia vegetal: Nutricao mineral.; Capim Colonião; Cerrado; Fisiologia Vegetal; Nitrato; Nitrogênio; Panicum Maximum.; Plant physiology.. |
Ano: 2001 |
URL: http://www.infoteca.cnptia.embrapa.br/infoteca/handle/doc/567073 |
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Collos, Y; Vaquer, A; Laabir, M; Abadie, Eric; Laugier, Thierry; Pastoureaud, Annie; Souchu, Philippe. |
A monitoring program with a weekly sampling frequency over a 15-month period indicates that urea concentrations above a certain threshold level may trigger the blooms of Alexandrium catenella in Thau lagoon. However, urea concentrations were also sometimes related to ammonium and dissolved organic nitrogen concentrations, indicating that the role of urea may not be a direct one. An original approach is used to assess the relative contribution of several nitrogen sources (nitrate, nitrite, ammonium, urea) to growth of A. catenella by comparing nitrogen uptake rates to nitrogen-based growth rates estimated from dilution experiments during four blooms over a 4-year period (2001-2004) in Thau lagoon. Nitrate and nitrite contributed 0.1-14% and 0.1-5%... |
Tipo: Text |
Palavras-chave: Uptake kinetics; Ammonium; Urea; Growth; Nitrogen; HAB; Alexandrium catenella. |
Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-6454.pdf |
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García-portela, Maria; Reguera, Beatriz; Gago, Jesus; Le Gac, Mickael; Rodríguez, Francisco. |
Dinoflagellate species of Dinophysis are obligate mixotrophs that require light, nutrients, and prey for sustained growth. Information about their nitrogenous nutrient preferences and their uptake kinetics are scarce. This study aimed to determine the preferred nitrogen sources in cultures of D. acuminata and D. acuta strains from the Galician Rías Baixas (NW Spain) and to compare their uptake kinetics. Well-fed versus starved cultures of D. acuminata and D. acuta were supplied with N15 labeled inorganic (nitrate, ammonium) and organic (urea) nutrients. Both species showed a preference for ammonium and urea whereas uptake of nitrate was negligible. Uptake rates by well-fed cells of D. acuminata and D. acuta were 200% and 50% higher, respectively, than by... |
Tipo: Text |
Palavras-chave: Dinophysis; Nitrate; Ammonium; Urea; Uptake rates; N-15 incubations; Antibiotic treatment. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00606/71770/70250.pdf |
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Collos, Yves; Husseini Ratrema, Julie; Bec, Béatrice; Vaquer, André; Hoai, Thong Lam; Rougier, Claude; Pons, Virginie; Souchu, Philippe. |
The dilution technique was used to estimate chlorophyll and pheopigment, net and gross production as well as zooplankton grazing over a 12-month period in a coastal lagoon in Southern France. Chlorophyll a (Cha) based gross growth rates of phytoplankton ranged from undetectable in February to 2.6 day(-1) in June, corresponding to 3.8 divisions per day. Cha-based grazing rates ranged from undetectable in February to 1.1 d(-1) in June. The seasonal growth pattern of picoplankton was similar to that of the whole community, with a peak in July, corresponding to four divisions per day. Grazing processes represented from 20 to 150% of the phytoplankton daily growth, and the grazing pressure was stronger on small phytoplankton cells than on larger cells. Gross... |
Tipo: Text |
Palavras-chave: Zooplankton; Ammonium; Pheopigments; Degradation; Growth; Phytoplankton. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-727.pdf |
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Aminot, Alain; Kerouel, Roger; Birot, Dominique. |
A version of the orthophthaldialdehyde-fluorescence ammonium determination for flow injection analysis (FIA) is presented here, with a view to its use for in situ, low-power consumption systems, Thus, the reaction temperature was limited to 30 degreesC and FIA was used in stop-Bow mode (3 min stop). The calibration is linear up to 50 mu mol l(-1), but concentrations up to 100 mu mol l(-1) can be measured. Repeatability is around 1% in the range of 0.5-4 mu mol l(-1) and the detection limit is about 0.03 mu mol l(-1) Over the salinity range of 5-35 (seawater practical salinity scale) the salt effect is almost negligible (within +/- 2%); and below salinity of 5 it increases to a maximum of -9% in fresh water compared to seawater. Hydrogen carbonate,... |
Tipo: Text |
Palavras-chave: In situ; Fluorometry; Flow injection analysis; Determination; Ammonium. |
Ano: 2001 |
URL: http://archimer.ifremer.fr/doc/2001/publication-1722.pdf |
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Cabrita, Mt; Catarino, F; Vale, C. |
The time-course evolution of ammonium concentration has been examined in the flood water during the first 25 min of tidal inundation. The way this transport fluctuates with the tidal ranges and wind conditions was investigated. Flood water was collected at three sites, located along a transect from the lower to the upper intertidal area of the Tagus estuary. At spring and intermediate tides, the periods of air exposure vary slightly along the transect due to the high tidal amplitude and the flatness of the area, but the upper site remains uncovered at neap tide over the entire tidal cycle. At each site, sampling was performed at different tidal ranges covering the neap-spring tidal cycle and wind conditions. Ammonium was determined in the flood water at... |
Tipo: Text |
Palavras-chave: Extraction par la marée; Ammonium; Sédiment intertidal; Estuaire; Tidal flushing; Ammonium; Intertidal sediments; Estuary. |
Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43611/43908.pdf |
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Jauzein, Cecile; Loureiro, Sofia; Garces, Esther; Collos, Yves. |
Short-term experiments were carried out to investigate whether interactions between ammonium (NH4+) and urea uptake regulate the total nitrogen assimilation of the toxic dinoflagellate Alexandrium catenella. To test for strain variability, 5 strains of A. catenella from the NW Mediterranean were used: 3 strains from the Thau lagoon (southern France) and 2 strains from the Catalonia basin (Spain). For each strain, the uptake rate of 1 nutrient (NH4+ or urea) at a reference concentration (10 mu gatN l(-1)) was measured as a function of the increasing concentration of the other nutrient (0 to 10 mu gatN l(-1)). Simultaneous N uptake rates of the distinct nitrogen sources were obtained from N-15-NH4+ and N-15-urea incorporation measurements. A strong... |
Tipo: Text |
Palavras-chave: Strain variability; Interactions; Urea; Ammonium; Alexandrium catenella. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6432.pdf |
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Registros recuperados: 45 | |
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