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S. Pawar - One of the best experts on this subject based on the ideXlab platform.
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The phytoplankton along a pollution gradient in the river Mahanadi (M.P. state) India – a multivariate approach
Hydrobiologia, 2000Co-Authors: K. S. Unni, S. PawarAbstract:Phytoplankton of the River Seonath, a major tributary of Mahanadi river system, was studied for 15 months together with physical–chemical variables in relation to a pollution gradient. Multivariate analysis and ordination by Principal Components Analysis of the physical–chemical variables and phytoplankton density indicated a community replacement along a pollution gradient. The dominant benthic diatom community, mainly comprising Achnanthes trigibba and A. affinis of the upstream was replaced by Chlorophycea at the middle stretch and Cyanophycea at the downstream sites. Chlorella, Scenedesmus and Coelastrum dominated among Chlorophyceae in the middle stretch in the highly polluted sites, followed by the Cyanophycean assemblage of Microcystis and Merismopedia.
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The phytoplankton along a pollution gradient in the river Mahanadi (M.P. state) India - a multivariate approach
Hydrobiologia, 2000Co-Authors: K. S. Unni, S. PawarAbstract:Phytoplankton of the River Seonath, a major tributary of Mahanadi river system, was studied for 15 months together with physical–chemical variables in relation to a pollution gradient. Multivariate analysis and ordination by Principal Components Analysis of the physical–chemical variables and phytoplankton density indicated a community replacement along a pollution gradient. The dominant benthic diatom community, mainly comprising Achnanthes trigibba and A. affinis of the upstream was replaced by Chlorophycea at the middle stretch and Cyanophycea at the downstream sites. Chlorella, Scenedesmus and Coelastrum dominated among Chlorophyceae in the middle stretch in the highly polluted sites, followed by the Cyanophycean assemblage of Microcystis and Merismopedia.
V Venkataramana - One of the best experts on this subject based on the ideXlab platform.
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influence of river discharge on abundance and composition of phytoplankton in the western coastal bay of bengal during peak discharge period
Marine Pollution Bulletin, 2018Co-Authors: M D Bharathi, V V S S Sarma, K Ramaneswari, V VenkataramanaAbstract:Abstract To understand the influence of river discharge on phytoplankton composition along western coastal Bay of Bengal (BoB), surface water samples were collected during peak discharge period. River discharge from the Ganges influences northwest (NW) coastal BoB whereas peninsular rivers (Godavari and Krishna) discharge to the southwest (SW) coastal Bay. River discharge from the Ganges is an order of magnitude higher than peninsular river resulting in low saline, less suspended matter and lower nutrients concentrations in the NW and contrasting to that was observed in the SW. ~50%of the phytoplankton were composed of Thalassiosira spp., Nitzschia spp., Microcystis spp., Amphiprora spp. and Thalassionema spp. in the SW whereas Thalassiosira spp., Nitzschia spp., Chaetoceros spp., Merismopedia spp. and Peridinium spp. in the NW. Significant variability in phytoplankton composition was observed from coast to offshore. Our study revealed that river discharge and associated physico-chemical characteristics governed the phytoplankton community along western coastal BoB.
Adámek Radek - One of the best experts on this subject based on the ideXlab platform.
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Seasonal dynamics and vertical distribution of Crustacea in the deep stratified reservoir Josefův Důl (the Jizera Mountains, Czech Republic)
Univerzita Karlova Přírodovědecká fakulta, 2015Co-Authors: Adámek RadekAbstract:Vodárenská nádrž Josefův Důl v Jizerských horách prochází složitým obdobím zotavování z antropogenní acidifikace, jehož důsledkem jsou mj. i nepředvídatelná sezónní maxima některých organismů. V posledních letech se jedná o masové namnožení pikosinic rodu Merismopedia (M. tenuissima), které tvoří v některých obdobích převládající složku fytoplanktonu a značně komplikují proces úpravy vody na vodu pitnou. Zooplankton se vyvíjí v souvislosti s ústupem acidifikace a vysazením lososovitých ryb na konci 90. let 20. století. Korýši jsou zastoupeni pouze několika druhy v obvykle malých počtech, převládaly perloočky Ceriodaphnia quadrangula a Holopedium gibberum. O rozmístění jednotlivých druhů filtrátorů ve vodním sloupci této hluboké nádrže nebylo nic známo. Cílem práce bylo popsat sezónní dynamiku a vertikální distribuci korýšů v nádrži Josefův Důl zejména v souvislosti s biotickými faktory prostředí (množství a kvalita potravy, kompetice, predace) a zjistit, zda v letním období dochází k jejich diurnálním vertikálním migracím.The zooplankton of Josefův Důl, a large and deep drinking water reservoir recovering from acidification, develop in relation to the improving water chemistry but also predation by salmonid fish re-stocked at the end of the 1990s. Crustacea are represented by small numbers of several species only, and nothing is known about their distribution in the water column. Recently, picocyanobacteria Merismopedia sp. became dominant in the phytoplankton, which hampers substantially the treatability of the raw water. The aim of the thesis is to describe the seasonal dynamics and vertical distribution of Crustacea in the Josefův Důl reservoir, together with parameters of the environment, and to study their possible diurnal vertical migrations in the summer period.Institute for Environmental StudiesÚstav pro životní prostředíPřírodovědecká fakultaFaculty of Scienc
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Seasonal dynamics and vertical distribution of Crustacea in the deep stratified reservoir Josefův Důl (the Jizera Mountains, Czech Republic)
2015Co-Authors: Adámek RadekAbstract:The zooplankton of Josefův Důl, a large and deep drinking water reservoir recovering from acidification, develop in relation to the improving water chemistry but also predation by salmonid fish re-stocked at the end of the 1990s. Crustacea are represented by small numbers of several species only, and nothing is known about their distribution in the water column. Recently, picocyanobacteria Merismopedia sp. became dominant in the phytoplankton, which hampers substantially the treatability of the raw water. The aim of the thesis is to describe the seasonal dynamics and vertical distribution of Crustacea in the Josefův Důl reservoir, together with parameters of the environment, and to study their possible diurnal vertical migrations in the summer period
Güler Aykulu - One of the best experts on this subject based on the ideXlab platform.
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A Study on the Occurrence of Merismopedia Meyen (Cyanobacteria) Populations on the Littoral Sediments of İzmit Bay (Turkey)
Turkish Journal of Botany, 2003Co-Authors: Yelda Aktan, Güler AykuluAbstract:In a previous study of epipelic diatoms on the littoral sediments of Izmit Bay (Marmara Sea, Turkey), which was carried out from March 1999 to September 2000, it was found that two Merismopedia Meyen species (Cyanobacteria) occurred frequently. In the present study, the seasonal variations of density and biomass of the Merismopedia species, which were dominant at certain times in the epipelic algal flora on the littoral sediments of Izmit Bay, were investigated. In addition, some physical and chemical parameters were measured. One of the species, Merismopedia glauca (Ehrenb.) Nageli, was dominant in terms of cell numbers and frequency while M. tenuissima Lemmerm. was found to be rare and was present in very low numbers. M. glauca was recorded at all seven stations and at certain times reached quite high numbers. The highest numbers were obtained from Station 4, which is characterised by being an area protected from wave action where the sediment is quite stable.
Joann M. Burkholder - One of the best experts on this subject based on the ideXlab platform.
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Phytoplankton and episodic suspended sediment loading: Phosphate partitioning and mechanisms for survival
Limnology and Oceanography, 1992Co-Authors: Joann M. BurkholderAbstract:Enclosures within a turbid reservoir were used in combination with short-term laboratory experiments to examine some effects of suspended sediment loading on the community structure and phosphate uptake of the phytoplankton. Phytoplankton communities in duplicate field enclosures were treated at 7-d intervals for 8 weeks with a natural, fine-particulate clay in hydrated form, for comparison with species composition and abundances in communities from control enclosures without sediment additions. The phytoplankton community in field enclosures 7 d after final sediment addition was similar to that in controls (without sediment additions). The colonial blue-green Merismopedia punctata was dominant in cell number, and mixotrophic and heterotrophic dinoflagellates were dominant in biomass (based on cell surface area). The surprisingly diverse dinoflagellate assemblage consisted mostly of delicate athecate Gymnodinium spp. which were missed by conventional preservation techniques. Autoradiographs from short-term laboratory assays with trace concentrations of 33P0,3- revealed that clay particles adsorbed the radiolabel and also stimulated 33P043p uptake among all phytoplankton taxa examined. Algal uptake of radiolabeled P was highest immediately after sediment addition, indicating that one mechanism for survival under episodic sediment loading may be rapid uptake of POa3- for subsequent use after adverse conditions. Other apparent mechanisms involved in phytoplankton survival included rapid colony fragmentation (Merismopedia), partial or complete reliance on heterotrophy (dinoflagellates), and rapid formation of temporary cysts (dinoflagellates). Such mechanisms likely facilitate the characteristic resilience of abundant phytoplankton in turbid systems. Suspended sediments scoured by rivers and overland runoff pour into lakes, impoundments, and estuaries throughout the world. The influence of episodic sediment loading on phytoplankton communities varies with the composition, aging, chem