Consulta: subjectFacets:"Bacterioplankton"
Registros recuperados: 26
Data/hora: 01/06/2024 07:45:54

Structure and dynamic of food webs in Andean North Patagonian freshwater systems: organic matter, light and nutrient relationships
Provedor de dados: 67
Autores: Modenutti,Beatriz; Albariño,Ricardo; Bastidas Navarro,Marcela; Díaz Villanueva,Verónica; Souza,María Sol; Trochine,Carolina; Laspoumaderes,Cecilia; Cuassolo,Florencia; Mariluán,Gustavo; Buria,Leonardo; Balseiro,Esteban.
North Andean Patagonian aquatic systems include a number of deep and shallow oligotrophic lakes with a profuse hydrographic net. In this contribution we present a review of the researches carried out during the last decade in the food webs of North Patagonian water bodies. Food webs in these systems were studied based on field surveys, combining with field and laboratory experiments. Deep and shallow lakes were analyzed in relation to light, organic matter, and nutrient constraints as limiting interacting factors. In addition, we have also extended our knowledge on the structure and dynamics of stream food webs by analyzing different aspects of biotic interactions occurring both through the autotrophic and heterotrophic pathways. Since Andean lakes were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Phytoplankton; Zooplankton; Fish; Insects; Lakes and rivers.
Ano: 2010
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1667-782X2010000200003

Responses of plankton and fish from temperate zones to UVR and temperature in a context of global change
Provedor de dados: 67
Autores: Gonçalves,Rodrigo J; Souza,María Sol; Aigo,Juana; Modenutti,Beatriz; Balseiro,Esteban; Villafañe,Virginia E; Cussac,Víctor; Helbling,E Walter.
In the last decades, both temperature and UVB (280-315 nm) radiation on the surface of the Earth increased at growing rates as a result of human activities. Many studies had evaluated the effects of temperature on aquatic ecosystems, but now the field broadens as the combination and variations of temperature and radiation gains especial importance. In this work we attempt to revisit some of our knowledge about the effects of UVR and temperature on marine and freshwater plankton and fish from temperate regions (defined here as latitudes between 30-60º), especially from the Patagonia area, due to the special characteristics found in these sites. UVR affects (often negatively) almost all processes, from carbon fixation to behavior; and certainly all trophic...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Climate change; Bacterioplankton; Phytoplankton; Zooplankton; Fish; Oxidative stress; Upper mixed layer.
Ano: 2010
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1667-782X2010000200005

Оценка сопоставимости двух методов количественного  учета морского гетеротрофного бактериопланктона
Provedor de dados: 13
Autores: Рылькова, О. А.; Поликарпов, И. Г.; Сабурова, М. А.
Проведены сравнительные исследования общей численности бактерий (ОЧБ) различными методами. В качестве красителей для окраски бактерий использовали эритрозин (Э) и флуорохромы (Ф): акридин оранжевый (АО) и профлавин. Материалами для работы послужили пробы, собранные в различных районах Черного моря в течение всего годового цикла: в 37 рейсе НИС «Профессор Водяницкий» (июль 1992 г., глубоководная часть с/в части Черного моря); в 43 рейсе НИС «Профессор Водяницкий» (сентябрь 1993 г., шельфовая зона, центральная часть и свал глубин с/з части Черного моря, центр западной халистазы); в эстуарии р. Черной (апрель 1994 г.); в Севастопольской бухте (февраль-март 1998 г.); во 2 рейсе НИС «Горизонт» (июнь 1998 г., шельфовая зона Крыма); в 11 рейсе НИС «Диорит»...
Tipo: Journal Contribution
Palavras-chave: Бактериопланктон; Флуорохромы; Эритрозин; Акридин; Профлавин; Bacterioplankton.
Ano: 2003
URL: http://repository.ibss.org.ua/dspace/handle/99011/586

Микропланктон западной части пролива Брансфилда: структура численности и биомассы в марте 2002 г.
Provedor de dados: 13
Autores: Серегин, С. А.; Кузьменко, Л. В.; Сысоев, А. А.; Гаврилова, Н. А.
Обсуждаются результаты исследований микропланктона (фито- и бактериопланктон, раковинные инфузо­рии) фотического слоя вод западной части пролива Брансфилда (Антарктика), проведенных в рамках 7-й Ук­раинской антарктической экспедиции (УАЭ) в марте 2002 г. Показатели обилия микропланктона в разных участках полигона различались в 2 - 40 раз. Учитывая видовую структуру и характер распределения числен­ности и биомассы микропланктона, на изученной акватории выделены несколько зон. Воды северной зоны -в пространстве между островами Смита, Сноу, Ливингстона и Дисепшен - с наибольшими значениями чис­ленности и биомассы микропланктона охарактеризованы как эвтрофные. Минимальные показатели отмече­ны в Юго-Восточной зоне - в районе о. Тринити и вдоль побережья...
Tipo: Journal Contribution
Palavras-chave: Сообщество микропланктона; Фитопланктон; Бактериопланктон; Распределение численно­сти и биомассы; Microplankton community; Phytoplankton; Bacterioplankton; Number and biomass distributions; Brans­field Strait.
Ano: 2005
URL: http://repository.ibss.org.ua/dspace/handle/99011/207

Microcalorimetry of the smallest plankton fraction: in search for the sources of heat dissipation
Provedor de dados: 13
Autores: Mukhanov, V. S.; Kemp, R. B.
Heat production by the plankton pico (0.2 to 2 μm) and femto (&lt;0.2 μm) fractions was measured in the dark using a microcalorimetric method. It was surprisingly found that the femtofraction (FF) produced more heat per seawater volume (48 ± 24  (95% CI) μW l-1) than the picofraction (25 ± 14 μW l-1). Consequently, we tested two hypotheses which could explain the phenomenon through a differentiation between the potential sources of heat in FF: (i) metabolism of ultramicrobacteria, the only living component in the fraction besides the non-metabolizing virioplankton which are unable to produce heat; (ii) extracellular chemical processes in aquatic environments. Results of microcalorimetry and respirometry combined with the use of antimicrobial agents...
Tipo: Journal Contribution
Palavras-chave: Microcalorimetry; Heat production; Ultramicrobacteria; Virioplankton; Bacterioplankton; Extracellular enzyme activity; Микрокалориметрия; Теплопродукция; Ультрамикробактерии; Вириопланктон; Бактериопланктон; Внеклеточная ферментативная активность.
Ano: 2005
URL: http://repository.ibss.org.ua/dspace/handle/99011/234

Сезонные и межгодовые изменения численности бактериопланктона в районе Аргентинских островов, Антарктика
Provedor de dados: 13
Autores: Серёгин, С. А.
Впервые для района Украинской антарктической станции Академик Вернадский (бывшая британская станция Фарадей) представлены результаты исследований обилия бактериопланктона для разных временных масштабов – сезонного и многолетнего. Общие закономерности сезонных изменений численности планктонных бактерий в исследуемом районе характеризовались минимальными показателями в позднезимний период (июль – сентябрь), возрастанием на порядок в весенне-летнее время и величинами численности, близкими к среднегодовым, - в осенний сезон (март – май). Наблюдаемые вариации сезонных изменений проявлялись в наличии или отсутствии резких подъемов численности в весенний период, связанных с выраженностью «цветения» микроводоросли Phaeocystis pouchetii, в длительности зимнего...
Tipo: Journal Contribution
Palavras-chave: Бактериопланктон; Численность; Биомасса; Сезонные изменения; Межгодовые вариации; Многолетний тренд; Bacterioplankton; Number; Biomass; Seasonal changes; Year-to-year variations; The long-standing trend.
Ano: 2009
URL: http://repository.ibss.org.ua/dspace/handle/99011/1083

Spatial and temporal variability of the pico- and nanophytoplankton and bacterioplankton in a deep Polynesian atoll lagoon
Provedor de dados: 5
Autores: Thomas, Y.; Garen, Pierre; Courties, C.; Charpy, L.
Spatial and temporal scales of variability in phyto- and bacterioplankton abundance were investigated in a deep atoll lagoon (Ahe, French Polynesia), Ahe Lagoon showed a classical phytoplankton composition, but its picophytoplankton (Prochlorococcus, Synechococcus and picoeukaryotes) concentrations are higher than the mean for Polynesian atoll lagoons. Phyto- and bacterioplankton descriptors were highly variable, with mean CVs of &gt;20% in most cases: day night, day-to-day, vertical, lagoonal and seasonal. Phytoplankton biomass, which was estimated by in vivo fluorescence, was higher in the deep layer than in the upper layer. This pattern was detected on a day night scale, showing transitory vertical gradients, and through long-term events that were...
Tipo: Text
Palavras-chave: Flow cytometry; Picophytoplankton; Nanophytoplankton; Bacterioplankton; Vertical distribution; Day-to-day dynamics; Large-scale heterogeneity; Deep atoll lagoon; French Polynesia.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00003/11425/7963.pdf

Les virus de l'estuaire de la Charente el du bassin de Marennes-Oleron. Dynamiques spatio-temporelles et  interactions avec les communautés bactériennes
Provedor de dados: 5
Autores: Auguet, Jean-christophe.
This study is divided in two parts; one aim is to evaluate the in situ spalio-temporal dynamics of viral communities  in the Charante estuary in order to define the appropriate seasons to conduct in vitro viral enrichment experiments. These experiments, that constitute the second part of this study, were performed to assess the impact of freshwater viruses carried by the Charante River on the dynamics and composition of coastal bacterial communities. With abundance ranging from 1.4 x 107 to 208 x I07 VLPml-1. viruses are the most abundant component among plankton microorganisms in surface waters of the Charente estuary. Thre temporal dynamics of this component reflects the indirect influence of temperature through the control of bacterial abundance,...
Tipo: Text
Palavras-chave: Richesse spécifique; Composition clonale; Enrichissement vital; Infection lyrique; Structure des communautés; MET; PPGE; Dynamique temporelle; Gradient de salinité; Estuaire; Bactérioplancton; Virioplancton; Species richness; Clonal composition; Viral enrichment; Lytic infection; Community structure; Diversity; TEM; PEGE; Temporal dynamic; Gradient; Salinity; Estuary; Bacterioplankton; Virioplankton.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/these-3071.pdf

Exoproteolytic activity in an Atlantic pond (France): estimates of in situ activity
Provedor de dados: 5
Autores: Crottereau, C; Delmas, Daniel.
In order to estimate in situ bacterial exoproteolysis and its contribution to bacterial secondary production (BSP), we studied microbial activities (BSP and kinetics of exoproteolytic activity) in relation to dissolved combined amino acids (DCAA) during the survey of an Atlantic marine pond. In this pond, high concentrations of DCAA (mean = 4.27 mu M), probably generated by zooplankton grazing, allowed large bacterial biomass development and high production (max = 10(11) cells l(-1) and 18.8 x 10(9) cells l(-1) d(-1) respectively). Exoproteolytic enzyme activity (mean V-m = 55.9 mu M d(-1)) was tightly cou pled to bacterial production, suggesting that protein utilization was essential for bacterial growth. Calculation, according to the Michaelis-Menten...
Tipo: Text
Palavras-chave: Bacterioplankton; In situ exoproteolytic hydrolysis rate; Kinetic parameters; DCAA; Marine pond.
Ano: 1998
URL: https://archimer.ifremer.fr/doc/00446/55803/62288.pdf

Exoproteolytic activity determined by flow injection analysis: its potential importance for bacterial growth in coastal marine ponds
Provedor de dados: 5
Autores: Delmas, Daniel; Legrand, Catherine; Bechemin, Christian; Collinot, Cecile.
The measurement of the fluorescent 4-methyl-7-coumarinylamine released from the hydrolysis of a non-fluorescent peptide model substrate by exoproteolytic enzymes has been adapted to flow injection analysis (FIA). FIA allows samples to be processed very quickly (less than 2 min. for triplicate determinations) with good sensitivity (&lt; 0.1 muM) and reproducibility (relative standard deviation &lt; 3 % at the 0.2 muM level). In a coastal marine pond, exoproteolytic activity was closely related to bacterioplankton biomass. The high activity measured in pond water (maximum velocity: V(M) almost-equal-to 1.46 to 2.54 muM.h-1) emphasizes the importance of dissolved protein hydrolysis for bacterial growth and for dissolved organic nitrogen cycling. The mean...
Tipo: Text
Palavras-chave: Activité exoprotéolytique; Protéine dissoute; Analyse en flux continu; Bactérioplancton; Marais maritime; Flow injection analysis; Exoproteolytic activity; Dissolved protein; Bacterioplankton; Coastal marine pond.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00196/30756/29163.pdf

Determination of the distribution of dissolved organic carbon in the Indian sector of the Southern Ocean
Provedor de dados: 5
Autores: Wiebinga, Cj; De Baar, Hjw.
During France JGOFS campaign ANTARES 2 (R.V. Marion Dufresne), samples were taken along a section of the 62 degrees E meridian from 49 degrees to 66 degrees S. The high temperature catalytic oxidation (HTCO) method was used to determine the concentration of dissolved organic carbon (DOC). The analyses were conducted both on-board ship and after the cruise in the laboratory. Collecting and storing acidified samples for post-cruise analysis induced no significant differences. The use of two separate but identical channels on the carbon analyzer increased the number of samples analysed per day and allowed independent monitoring of the instrument blank and the calibration of the detector response. The mixed layer concentrations of organic carbon varied from...
Tipo: Text
Palavras-chave: Dissolved organic carbon (DOC); Apparent oxygen utilization (AOU); Bacterioplankton; Mineralisation.
Ano: 1998
URL: https://archimer.ifremer.fr/doc/00100/21113/18933.pdf

Eutrophication in a tropical pond: Understanding the bacterioplankton and phytoplankton dynamics during a vibriosis outbreak using flow cytometric analyses
Provedor de dados: 5
Autores: Lucas, Ronan; Courties, C.; Herbland, Alain; Goulletquer, Philippe; Marteau, Anne-laure; Lemonnier, Hugues.
In tropical shrimp ponds, the increasing of feed input, concomitantly with the stocking shrimp biomass, induces an eutrophication of the ecosystem. Although difficult to maintain, its stability is required to guarantee the success of the culture. A 110-day period of phytoplankton and bacterioplankton stock and dynamics in an earthen pond (1.2 ha area, 1 m depth) was monitored using flow cytometry to provide baseline information on community characteristics and ecosystem instability. Seven autotrophic cell types were identified over the whole sampling period. Prokaryotic cells included Synechococcus sp., a group named UNK which presented an atypical new flow cytometric signature and picoeukaryotes (PEUK). Nanophytoplankton cells were represented by 4...
Tipo: Text
Palavras-chave: Tropical shrimp aquaculture; Ecosystem shift; Phytoplankton; Bacterioplankton; Vibrio; Flow cytometry.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00029/14068/11312.pdf

Microbial food web structural and functional responses to oyster and fish as top predators
Provedor de dados: 5
Autores: Mostajir, Behzad; Roques, Cecile; Bouvier, Corinne; Bouvier, Thierry; Fouilland, Eric; Got, Patrice; Le Floc'H, Emilie; Nouguier, Jean; Mas, Sebastien; Sempere, Richard; Sime-ngando, Telesphore; Troussellier, Marc; Vidussi, Francesca.
The impact of fish and oysters on components of the pelagic microbial food web (MFW) was studied in a 10 d mesocosm experiment using Mediterranean coastal waters. Two mesocosms contained natural water only ('Controls'), 2 contained natural water with Crassostrea gigas ('Oyster'), and 2 contained natural water with Atherina spp. ('Fish'). Abundances and biomasses of microorganisms (viruses, bacteria, phytoplankton, heterotrophic flagellates, and ciliates) were measured to estimate their contribution to the total microbial carbon biomass. Two MFW indices, the microbial autotroph: heterotroph C biomass ratio (A:H) structural index and the gross primary production: respiration ratio (GPP:R) functional index, were defined. In the Fish mesocosms, selective...
Tipo: Text
Palavras-chave: Microbial food web; Virioplankton; Bacterioplankton; Phytoplankton; Protozooplankton; Crassostrea; Atherina; Autotrophy; Heterotrophy.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00284/39489/73675.pdf

Ultraviolet radiation induces reversal of the bioavailability of DOM to marine bacterioplankton
Provedor de dados: 5
Autores: Obernosterer, I; Sempere, R; Herndl, Gj.
2-fold higher in the &lt;20 kDa fraction than in the bulk DOM. These results clearly indicate that initially bioreactive DOM can be rendered biologically more recalcitrant by exposure to solar radiation, while DOM of initially low bioavailability can be, at least partly, photochemically transformed to compounds of higher biological reactivity.
Tipo: Text
Palavras-chave: Dissolved organic matter; Ultraviolet radiation; DOM-photoreactivity; Bacterioplankton; Southern Ocean.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/00220/33170/31686.pdf

Effects of experimental warming on small phytoplankton, bacteria and viruses in autumn in the Mediterranean coastal Thau Lagoon
Provedor de dados: 5
Autores: Courboulès, Justine; Vidussi, Francesca; Soulié, Tanguy; Mas, Sébastien; Pecqueur, David; Mostajir, Behzad.
To investigate the responses of a natural microbial plankton community of coastal Mediterranean waters to warming, which are still poorly known, an in situ mesocosm experiment was carried out in Thau Lagoon during autumn 2018. Several microorganisms, including virio-, bacterio-, and phytoplankton &lt; 10 µm in size, were monitored daily and analysed using flow cytometry for 19 consecutive days in six mesocosms. Three mesocosms (control) had the same natural water temperature as the lagoon, and the other three were warmed by + 3 °C in relation to the control temperature. The cytometric analyses revealed an unexpected community dominated by picophytoplanktonic cells, including Prochlorococcus-like and Picochlorum-like cells, which had not previously been...
Tipo: Text
Palavras-chave: Pico- and nanophytoplankton; Bacterioplankton; Virus; Warming; In situ mesocosm; Thau lagoon.
Ano: 2021
URL: https://archimer.ifremer.fr/doc/00688/79979/82933.pdf

Seasonal variability in microplanktonic biomasses in the Gironde dilution plume (Bay of Biscay): relative importance of bacteria
Provedor de dados: 5
Autores: Artigas, Lf.
Bacterial and phytoplankton biomasses were estimated in a four-year study along a saline gradient (the dilution plume of the Gironde estuary on the Aquitanian continental shelf), by measuring bacterial abundance and mean cell volumes (epifluorescence counts) and chlorophyll-a concentrations tin vitro fluorescence). The spatial and temporal distribution of phytoplankton enabled us to determine the seasonal succession of algal blooms, sprouting in the marine waters of the inner shelf in early spring (picoplanktonic forms), reaching their annual maximum (10 mu g L-1) in plume waters in advanced spring, and moving to estuarine waters in the summer (&gt; 20 mu m forms). Bacterial biomasses followed mainly a decreasing dilution gradient, especially in winter and...
Tipo: Text
Palavras-chave: Bactéries; Phytoplancton; Rapport des biomasses microbiennes; Variabilité saisonnière; Panache de dilution girondin; Bacterioplankton; Phytoplankton; Microbial biomass ratio; Seasonal variability; Gironde dilution plume.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/00325/43659/43210.pdf

Nuevos registros de cianobacterias planctónicas en la Bahía de Jigüey, Cuba
Provedor de dados: 20
Autores: Dobal, V.; Lugioyo, G. M.; Alamo, B.; Loza Álvarez, S.
En el presente trabajo se presenta una lista de  21 especies de cianobacterias planctónicas encontradas en la Bahía de Jigüey (Cuba), que no habían sido informadas para las aguas costeras cubanas. Las muestras se colectaron en los meses de diciembre del 2010 y septiembre del 2011. Los resultados de este trabajo contribuyen a enriquecer el conocimiento de la biodiversidad microbiana marina en Cuba.
Tipo: Journal Contribution
Palavras-chave: Bacterioplankton; Biodiversity; Coastal environment; Cyanobacteria; Biodiversity; Coastal area.
Ano: 2012
URL: http://hdl.handle.net/1834/4591

Photo-degradation effect on dissolved organic carbon availability to bacterioplankton in a lake in the upper Paraná river floodplain - doi: 10.4025/actascibiolsci.v35i1.11054
Provedor de dados: 3
Autores: Teixeira, Mariana Carolina; Universidade Estadual de Maringá; Rodrigues de Azevedo, Júlio César; Universidade Tecnológica Federal do Paraná; Pagioro, Thomaz Aurélio; Universidade Tecnológica Federal do Paraná / Universidade Estadual de Maringá.
Dissolved organic carbon (DOC) is nowadays recognized as the main substrate and source of energy for aquatic microbial community. The great part of available organic carbon for bacterioplankton might be formed after photolytic degradation of humic material, which constitutes the major part of DOC in almost all natural waters. The effects of DOC photo-degradation were evaluated, as was its utilization by bacterioplankton, through a two-step experiment, one involving photo-degradation of DOC and the other bacterial growth on the photo-degraded substrate. Photo-degradation was responsible for the consumption of 19% of DOC, reduced SUVA254, an increase in the E2/E3 and E3/E4 ratios, in addition to modifications in the fluorescence spectra that indicated a rise...
Tipo: Experimento
Palavras-chave: 2.05.00.00-9 dissolved organic carbon; Bacterioplankton; Photo-degradation; Experiment Ecologia.
Ano: 2012
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/11054

Short-term variability of bacterioplankton in the maximum turbidity zone in the Paranaguá Bay, Southern Brazil, and its relationship with environmental variables
Provedor de dados: 52
Autores: Ribeiro,Catherine Gérikas; Kolm,Hedda Elisabeth; Costa Machado,Eunice da.
In this work, the density of bacterioplankton, bacterial biomass and environmental variables were monitored in two seasons (summer and winter), two times each month (spring tide and neap tide sampling), over a 12 h period, comprising a tidal cycle (semidiurnal), from subsurface and bottom waters, in a fixed station in the Estuarine Turbidity Maximum Zone (ETMZ) of Paranaguá Bay, Brazil. The data were treated with multivariate analyses methods in order to indentify the key controlling factors of the bacterial community dynamics. The microbial community seemed to be structured by a close relationship with the nutrients concentration, mainly by total phosphorous and nitrate. Regardless of variations throughout the tidal cycles, free-living bacteria had a...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Estuarine Turbidity Maximum Zone; Free-living bacteria; Attached bacteria; Paranaguá Bay.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000500012

Bacterial production in Guanabara Bay (Rio de Janeiro, Brazil) evaluated by ³H-leucine incorporation
Provedor de dados: 52
Autores: Gonzalez,Alessandra M.; Paranhos,Rodolfo; Andrade,Luciana; Valentin,Jean L.
The aim of this work was to evaluate the necessary ³H-leucine concentration to estimate bacterial production in Guanabara Bay through saturation curves. A second aim was to collect preliminary data of bacterial production in two distinct sites corresponding to different water qualities: Urca inlet and Governador Island. Saturation curves were made with water samples taken at the main circulation channel of the bay, Paquetá Island, and the two sites mentioned before. The ³H-leucine curves showed similar pattern for all studied areas, indicating the ideal isotope concentration to be 10 nM. Bacterial biomass production ranged from 0.40 to 4.53 µgC L-1 h-1 in Urca and from 3.86 to 73.72 µgC L-1 h-1 in Governador Island indicating the relationship between...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Activity measurement; Heterothrophic production; Estuary; Water pollution; Eutrophication.
Ano: 2000
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132000000500008

Bacteria and phytoplankton production rates in eight river stretches of the middle Rio Doce hidrographic basin (southeast Brazil)
Provedor de dados: 52
Autores: Petrucio,Mauricio Mello; Barbosa,Francisco Antônio R.; Thomaz,Sidinei Magela.
Measurements of bacterial secondary production (BSP), together with primary phytoplanktonic production (PPP) were conducted during dry and rainy seasons, in eight rivers of different orders submitted to different degrees of human impacts (different trophic degree). We aimed to determine and compare the importance of BSP and PPP in carbon fixation in these different lotic ecosystems. Our results showed that the Ipanema River was the most modified system by anthropogenic effluents inputs. These inputs altered the trophic degree and BSP rates of these streams and rivers.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Carbon; Phytoplankton; Rivers; Trophic state.
Ano: 2005
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132005000300019

Seasonal and spatial distribution of Bacterioplankton in a fluvial-lagunar system of a tropical region: density, biomass, cellular volume and morphologic variation
Provedor de dados: 52
Autores: Araújo,Magnólia Fernandes Florêncio de; Godinho,Mirna Januária Leal.
The temporal and spatial fluctuations of Bacterioplankton in a fluvial-lagunar system of a tropical region (Pitimbu River and Jiqui Lake, RN) were studied during the dry and the rainy periods. The bacterial abundance varied from 2.67 to 5.1 Cells10(7)mL-1 and did not show a typical temporal variation, presenting only small oscillations between the rainy and the dry periods. The bacterial biomass varied from 123 µgC L-1 to 269 µgC L-1 in the sampling sites and the average cellular volume varied from 0.12 to 0.54µm³, showing a predominance of the rods. The temperature showed a positive correlation with the cellular volume of the rods (R=0.55; p=0.02) and vibrio (R=0.53; p=0.03). Significant spatial differences of biomass (Mann Whitney: p=0.01) and cellular...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Biomass; Morphologic variation; Tropical environment.
Ano: 2008
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132008000100024

Yearly variation of bacterial production in the Arraial do Cabo protection area (Cabo Frio upwelling region): an evidence of anthropogenic pressure
Provedor de dados: 58
Autores: Coelho-Souza,Sérgio A.; Pereira,Gilberto C.; Coutinho,Ricardo; Guimarães,Jean R.D.
Arraial do Cabo is where upwelling occurs more intensively on the Brazilian coast. Although it is a protection area it suffers anthropogenic pressure such as harbor activities and sporadic sewage emissions. Short-time studies showed a high variability of bacterial production (BP) in this region but none of them evaluated BP during long periods in a large spatial scale including stations under different natural (upwelling and cold fronts) and anthropogenic pressures. During 2006, we sampled surface waters 10 times (5 in upwelling and 5 in subsidence periods) in 8 stations and we measured BP, temperature as well as the concentrations of inorganic nutrients, pigments and particulate organic matter (POM). BP was up to 400 times higher when sewage emissions...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Heterotrophic activity; Impacted area; Extractive reserve; Upwelling system.
Ano: 2013
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822013000400046

Heterotrophic bacteria abundances in Rodrigo de Freitas Lagoon (Rio de Janeiro, Brazil)
Provedor de dados: 58
Autores: Gonzalez,Alessandra M.; Paranhos,Rodolfo; Lutterbach,Márcia S.
The Rodrigo de Freitas Lagoon (RJ, Brazil) is an important coastal ecosystem that has been submitted to an accelerated degradation process. The aim of this work was to determine the abundance and the spatial distribution of total heterotrophic (by flow cytometry) and cultivated bacteria ("pour plate" method on R2A agar). Another objective was to evaluate the lagoon's influence on water quality of Ipanema and Leblon beaches. Physical and chemical data were acquired too. Sub-superficial water samples were taken monthly, from December 1999 to October 2000. On lagoon, the cultivated bacteria abundance varied from 6.9x10(5) to 5.0x10(7) CFU.100 mL-1. On Ipanema and Leblon beaches, this parameter yielded 1.4x10(5) and 2.8x10(6) CFU.100 mL-1, respectively. Total...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Bacterioplankton; Flow cytometry; Eutrophication; Water pollution; Rodrigo de Freitas Lagoon.
Ano: 2006
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822006000400005

Bacterioplankton features and its relations with doc characteristics and other limnological variables in Paraná river floodplain environments (PR/MS-Brazil)
Provedor de dados: 58
Autores: Teixeira,Mariana Carolina; Santana,Natália Fernanda; Azevedo,Júlio César Rodrigues de; Pagioro,Thomaz Aurélio.
Since the introduction of the Microbial Loop concept, many studies aimed to explain the role of bacterioplankton and dissolved organic carbon (DOC) in aquatic ecosystems. Paraná River floodplain system is a very complex environment where these subjects were little explored. The aim of this work was to characterize bacterial community in terms of density, biomass and biovolume in some water bodies of this floodplain and to verify its temporal variation and its relation with some limnological variables, including some indicators of DOC quality, obtained through Ultraviolet-visible (UV-VIS) and fluorescence spectroscopic analysis. Bacterial density, biomass and biovolume are similar to those from other freshwater environments and both density and biomass were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DOC; Spectroscopy; Bacterioplankton; Floodplain.
Ano: 2011
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822011000300008

Use of molecular approach to verify the influence of a eutrophic lagoon in the nearby ocean's bacterioplankton communities
Provedor de dados: 58
Autores: Taketani,Rodrigo Gouvêa; Araujo,Fábio Vieira; Weerelt,Margaretha Denise Maria van; Sanchez-Nunez,Maria Leonisa; Aniszewski,Erick; Rosado,Alexandre Soares.
Rodrigo de Freitas lagoon is an eutrophic aquatic environment. The waters from the lagoon are released to the sea at Ipanema and Leblon beaches, through Jardim de Alah channel. In this work, the influence of these waters on the bacterial communities of these beaches was investigated. Eleven sampling stations were set between the lagoon and the beaches, and the samples were analyzed by molecular and microbiological parameters. PCR-DGGE of the DNA extracted from the samples was performed using rpoB primers. Preliminary results indicate that all used approaches could reveal the influence of the lagoon on the beaches bacterial communities.
Tipo: Info:eu-repo/semantics/article
Palavras-chave: DGGE; Diversity; Bacterioplankton; Eutrophic lagoon.
Ano: 2003
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822003000500017