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Showing 1 to 20 of 51 for “"Hypolimnion"”.
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Calcitfällung und Phosphor-Kopräzipitation im Phosphorhaushalt eines eutrophen Hartwassersees mit anoxischem Hypolimnion (Willersinnweiher, Ludwigshafen am Rhein)
Untersucht wurde die autochthone Calcitfällung mit der Kopräzipitation von Phosphor hinsichtlich der Bedeutung für den trophischen Zustand und die trophische Entwicklung des eutrophen Willersinnweihers. Die Beprobungen des Sees in hoher zeitlicher Auflösung mit der Analyse zahlreicher …
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Diffuser Operations at Spring Hollow Reservoir
… dense epilimnion on top and the colder, denser, hypolimnion on the bottom. The epilimnion remains saturated with dissolved oxygen (DO) from mass transfer with the atmosphere, while the hypolimnion continues to undergo oxygen-depleting processes. During seasons of high oxygen demand the …
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Effects of seasonal habitat limitations on the distribution and energetics of stocked salmonids in Lake Moomaw, Virginia
… from July to September, but were located in the hypolimnion (<12°C) in October. Adult brown trout were located in the metalimnion during July, but were distributed in the hypolimnion from August to October. Adult trout in the hypolimnion were at low temperature (10°C) and diminished dissolved …
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The effects of hypolimnetic oxygenation on the chemical, physical, and biological properties of a shallow drinking water reservoir
… by withdrawing oxygen-depleted water from the hypolimnion to an on-site facility and injecting it with oxygen under high pressure before returning it to the hypolimnion. While this technique has been studied in select water bodies, to date it has not been successfully deployed in a shallow …
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The redox and iron-sulfide geochemistry of Salt Pond and the thermodynamic constraints on native magnetotactic bacteria
… the base of the chemocline and in the sulfidic hypolimnion. This distribution may be attributed to analyte profiles within the pond; depth profiles show a sudden drop of dissolved oxygen (DO) at the chemocline associated with an increase in dissolved Fe (II) concentrations that peak where both …
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Controlling Dissolved Oxygen, Iron and Manganese in Water-Supply Reservoirs using Hypolimnetic Oxygenation
… that aids distribution of oxygen throughout the hypolimnion. The induced mixing also creates an undesirable effect by increasing hypolimnetic oxygen demand (HOD). Nevertheless, oxygenation systems are commonly used and long-term oxygenation is hypothesized to actually decrease HOD. Increased …
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Hypolimnetic Oxygenation: Coupling Bubble-Plume and Reservoir Models
… well to observations. Oxygen transfer within the hypolimnion was independent of all parameters except initial bubble radius. The results of this work suggest that plume dynamics and oxygen transfer can successfully be predicted for linear bubble plumes using the discrete-bubble approach. To model …
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The Effects of Hypoxia on Zooplankton Communities in Lakes and Reservoirs
… concentrations (hypoxia) in their bottom waters (hypolimnion), which can disrupt ecological communities. Zooplankton, important aquatic organisms for regulating water quality and food webs, are one group of organisms affected by hypoxia since zooplankton need oxygen to respire. My research shows …
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The sources and cycles of iron and manganese in surface water supplies
… dissolved oxygen (DO) concentrations in the hypolimnion of stratified drinking water reservoir on Fe and Mn oxidation and removal. Results from a whole-ecosystem experiment showed that increasing DO concentrations through hypolimnetic oxygenation was effective for preventing the accumulation …
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High-frequency sensor data capture short-term variability in Fe and Mn cycling due to hypolimnetic oxygenation and seasonal dynamics in a drinking water reservoir
… dynamics and redox conditions in the hypolimnion. However, short-term (i.e., sub-weekly) trends in Fe and Mn cycling are less well-understood, as most monitoring efforts focus on longer-term (i.e., monthly to yearly) time scales. The potential for elevated Fe and Mn to degrade water …
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The redox and iron-sulfide geochemistry of Salt Pond and the thermodynamic constraints on native magnetotactic bacteria
… the base of the chemocline and in the sulfidic hypolimnion. This distribution may be attributed to analyte profiles within the pond; depth profiles show a sudden drop of dissolved oxygen (DO) at the chemocline associated with an increase in dissolved Fe(II) concentrations that peak where both O2 …
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Coupled arsenic, iron, and nitrogen cycling in arsenic-contaminated Upper Mystic Lake
… arsenic (As) remobilization and cycling in the hypolimnion of As-contaminated Upper Mystic Lake (UML; Winchester, MA). We conducted field and laboratory studies, and applied mass balance, surface complexation, and thermodynamic modeling to explore As cycling and its links to other elemental …
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Transport of perchlorate in the Las Vegas Wash and Lake Mead
… levels within the epilimnion, metalimnion and hypolimnion layers of the Lake, and to correlate perchlorate levels with total dissolved solids concentrations. Investigation showed that multiple sources contribute to the perchlorate contamination in the Wash. Perchlorate levels had increased …
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A reexamination of stratification processes in Ides Cove, N.Y. with reference to sediment geochemistry
… Cl- concentrations and conductivity in the hypolimnion have remained high due primarily to the saline discharge of ground water streams (mean annual Cl- = 303 mg/1). The discharge of saline ground water streams into the cove will affect mixing periods with autumnal and vernal turnover …
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The effects of lake dynamics on the water quality of Abel Lake Reservoir
… process brings poor quality water from the hypolimnion to the surface where it is drawn into the treatment facility and creates treatment problems. Results also show that algal growth and nutrient concentrations were moderate during the study, however, the potential for cultural …
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Sediment-Pore Water Chemistry of Taupo Volcanic Zone Lakes and the Effect Trophic State has on Exchange with the Water Column
… [N2] Samples were collected from the epilimnion, hypolimnion, benthic nepheloid layer and at 5 cm intervals from the sediment pore waters at monthly intervals for one year. Values of δ15N [N2] ranged from -1 to 0.28 ‰ in the epilimnion, -1.5 to 1.25 ‰ in the hypolimnion, -1.8 to 12.2 ‰ in the …
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Speciation and dynamics of phosphorus in relation to lake restoration methods
… lake. The sources and sinks of nutrients in the hypolimnion of Lake Okaro were investigated using field measurements in a comprehensive nutrient budget model in order to determine changes in sediment nutrient fluxes resulting from a whole lake sediment capping trial using Z2G1. Sediment nutrient …
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A study of nitrification in lakes of the English Lake District
… for up to 15% of the total oxygen deficit of the hypolimnion. At similar in situ temperatures nitrification rates and nitrifying bacterial populations were greater in oxidised sediments than in the water column. Littoral sediments were more important than profundal sediments as sites of …
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Aeration of Stockade Lake, South Dakota
… and dissolved oxygen concentrations in the hypolimnion were not raised sufficiently to increase the volume of fish habitat. The effects of aeration described in this paper show that individual lake characteristics and weather may determine the extent of limnological changes.
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A productivity study on Smith Mountain Lake
… Evaluation of the productivity potential of the hypolimnion of Smith Mountain Lake indicated that destratification would be detrimental to water quality. Stratification in Smith Mountain Lake was only slightly affected by the pump-back from lower Leesville Lake. Equations were developed in this …
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