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Showing 1 to 20 of 35 for “"Phosphorus concentration"”.
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Dynamic chamber system for determining equilibrium phosphorus concentration (EPC0) in sediments
… economic and ecological challenges to humanity. Phosphorus (P) is a common limiting nutrient in North American freshwater lakes including the Laurentian Great Lakes that is transported to receiving waters by rivers and streams, especially those adjacent to agricultural lands. The bed sediment of …
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Assessment of total phosphorus concentration as a predictor and determinant of fishery productivity in southern Appalachian reservoirs: application to Smith Mountain Lake, Virginia
Phosphorus is often the limiting nutrient of primary productivity in southern Appalachian reservoirs, but its impact on higher trophic levels has not been assessed. Regression analysis was used to examine the relationship between total phosphorus concentrations and estimates of fish standing stock …
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Does the foliage of Acacia spp. determine their distribution? : a study to determine how two different leaf forms may alter the distribution of Acacia spp. in relation to phosphorus concentration, mean annual precipitation and temperature within Australia and South Africa
… driver of phyllodes. However due to the very low concentrations of nutrients particularly P within Australia and the generally longer life span exhibited by phyllodes compared to normal compound leaves, we hypothesized that phyllodes were in fact an adaptation to nutrient limitation, and provide a …
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Landsat Trophic State Assessment of Fellows Lake
… trophic state indexes computed for chlorophyll a concentration and secchi depth measurements. Phosphorus concentration is shown to be a good trophic state predictor variable and secchi depth a poor predictor variable.
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A productivity study of the Roanoke River above Niagra Dam
… analysed for general chemical parameters and the phosphorus and nitrogen concentrations. The "Algal Assay Procedure Bottle Test" was than run on the samples and on the sample with phosphorus and/or nitrogen spikes to determine potential productivity and what we limiting potential productivity. …
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An Examination of Trophic State Indices For Some Missouri Reservoirs
… A trophic state indicator based upon total phosphorus concentration is also discussed.
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Technological Innovations for Mid-Atlantic Cropping Systems
… which exhibits decreased growth at elevated phosphorus concentration, for serving as in indicator of plant available phosphorus. An indicator crop could provide greater spatial resolution compared to soil testing, as well as represent plant available nutrients as opposed to chemically …
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Effects of Seed Applied Fungicide on Arbuscular Mycorrhizal Colonization of South Dakota Cultivars of Oat, Soybean, and Corn
… fungicide on arbuscular colonization rate or on phosphorus concentration of the host relative to the control. The use of Raxil MD was found to result in a significantly lower (p≤0.05) arbuscular colonization rate compared to the use of Evergol Energy. Total colonization was also significantly …
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Prediction of struvite formation potential in Ebpr digested sludge using mass balances, batch precipitation tests, and chemical equilibrium modeling
… plants that include enhanced biological phosphorus removal (EBPR) in their treatment process have the potential to form struvite (MgNH4PO4·6H 2O). The potential can be determined by the concentrations of struvite constituents including phosphorus, ammonium, and magnesium. Phosphorus …
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Investigation of the Effects of COD/TP Ratio on the Performance of a Biological Nutrient Removal System
… the effects of COD/TP ratio on the rates of phosphorus removal, COD removal, nitrogen removal, PHB utilization and oxygen uptake. The system was fed with municipal wastewater and operated at 20° C. The influent COD concentration was held approximately constant while the phosphorus …
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Nahrungsnetzbewirtschaftung in Mittelgebirgstalsperren
… conditions in relation to the given nutrient concentrations? 2. What are the underlying mechanisms? With the exception of the oligotrophic Große Dhünn Reservoir, "Biomanipulation" resulted in a shift of zooplankton body-size structure to larger daphnids in all the reservoirs. The …
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The effects of a phosphate detergent ban on a biological nutrient removal plant and anaerobic digester
… study investigated the effects of the detergent phosphorus ban implemented on January 1, 1988 in Virginia, on the treatment streams of the York River Wastewater Treatment Plant, a biological nutrient removal (BNR) system. Evaluation of the available historical data indicated that the influent …
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An evaluation of particulate phosphorus storage in an agricultural estuary
… of a fine sediment and particulate associated phosphorus budget in a typical agricultural estuary. Firstly, to explore catchment inputs, turbidity and flow were monitored continuously upstream of the freshwater/saline interface on the main stem channel of the south Devon River Avon, which …
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Interactions Between Land Use and Local Lithology on Phosphorus Distribution in Northrup Creek Sediments, Monroe County, New York
Phosphorus, a key nutrient in many aquatic systems that limits the growth of algae, plays a key role in the occurrence of eutrophication and toxic algal blooms. Past research has shown that land use and lithology are major contributors of phosphorus in a creek. High levels of organic phosphorus …
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Kinetics of enhanced phosphorus removal in the activated sludge process
An investigation into the removal of phosphorus in the activated sludge process showed that: (1) Luxury uptake of phosphorus may be induced by the presence of an anoxic zone (2) If a primary and secondary anoxic reactor are present in the system, the actual retention time of the primary anoxic …
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Phosphorus adsorption by selected clay minerals
… effect of certain cations on the adsorption of phosphorus by clay minerals. The various diffuse double layer and Donnan equilibrium theories were used in this theoretical treatment. Three standard clay minerals, a kaolinite, an illite and a montmorillonite were used in the investigation of the …
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The effect of high pressure on S and Te-doped GaAs1-xPx
… doped with sulfur and tellurium and have carrier concentrations in the 10^18 - 10^19 range. Changes in the resistivity as large as four orders of magnitude are observed at 77 0K for samples in the composition range 0.30 ~ x ~ 0.4~ The behavior of the samples is consistent with a model in which the …
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An assessment of factors controlling the biodegradation of benzene in the subsurface environment
… experiments were prepared with initial benzene concentrations of 1, 10 and 50 mg/L. For each soil, logistic, zero-, first-, and 3/2- order kinetic models were fit to benzene disappearance versus time data by regression analysis. The logistic and 3/2-order models fit the data better than zero- …
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Nitrate utilization as the final electron acceptor in a biological phosphorus removal system
… as the final electron acceptor in biological phosphorus removal systems was investigated. The objectives of the study were (1) to determine whether polyphosphate (polyP) microorganisms can use nitrate as the final electron acceptor, and (2) to evaluate and compare polyP accumulation in the …
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Maximization of the Electrochemical Detection of Orthophosphate in Organic-Aqueous Solutions.
It is well known that phosphorus is an essential nutrient for the growth of organisms. Therefore, it plays an important role as a growth-limiting nutrient in natural waters. Phosphorus-stimulated proliferation of plant micro- and macroorganisms in natural waters accelerates eutrophication thereby …
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