Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 20 of 21 for “"Phosphorus Cycling"”.
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Phosphorus cycling in organic systems
Soil phosphorus (P) is often unavailable in SK soils due to immobilization by microbial biomass and complexation with cations. The prohibition of synthetic fertilizer use in organic systems means farmers rely on crop rotation or approved inputs to supply P for crops. Legumes in crop rotation add P …
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Sediment Phosphorus Cycling in a Managed System Irondequoit Bay, N.Y.
The current status of internal phosphorus loading was evaluated in Irondequoit Bay, NY, an embayment of Lake Ontario. Sediment core incubation experiments and phosphorus water column profiles were used to quantify the release rate of phosphorus from the deepwater sediments of Irondequoit Bay during …
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Phosphorus cycling in the Gulf of Maine : a multi-tracer approach
Thesis (Ph.D.)--Joint Program in Oceanography, Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution, 1999 [February 1999]
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Cosmogenic ³²P and ³³P in the atmosphere and aligotrophic ocean and applications to the study of phosphorus cycling
… days) are powerful tracers of upper ocean P cycling, when coupled with time-series of the atmospheric sources. A method was developed to determine the low-level beta activities in rainwater and plankton. The wet deposition rates of P-32 and P-33 were determined during 12 months at a marine …
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Cosmogenic 32P and 33P in the atmosphere and aligotrophic ocean and applications to the study of phosphorus cycling
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1993.
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Seasonal responses of carbon, nitrogen, and phosphorus cycling to woodland reduction and different organic matter additions in the semiarid Great Basin
… but that microbial functions that regulate cycling of N and P were resilient to disturbance two years following implementation of the treatments. Our results shed light on how fuels treatments that alter organic matter inputs can in turn influence the ratios of C to nutrients in soil. These …
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A preliminary study of the impacts of alien Acacia infestation (A saligna) on the relative rates of nitrogen and phosphorus cycling in Lowland Fynbos, southwestern Cape, South Africa
… 1988. Environmental factors, nitrogen and phosphorus pool sizes and mineralization processes were investigated in the surface soils (1-10cm) of 7-8 year old fynbos vegetation and an adjacent Acacia saligna (Labill.) Wendl. infestation. While there was no significant difference in soil …
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Phosphorus Cycling in the Ellison Park Wetland at the Mouth of Irondequoit Creek, Rochester, NY: A Case Study Evaluating the Movement of Phosphorus as it Transits a Coastal Wetland of Lake Ontario
… three objectives: what role hydrology plays in phosphorus (P) removal efficiency of the Ellison Park Wetland complex; what role sediments play in the retention or release of P; and the possibility of predicting P discharge from the Ellison Park Wetland into Irondequoit Bay. The results for …
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Characterizing water quality, nutrients, and dissolved oxygen dynamics in four Lake Ontario coastal wetlands
… Frenchman’s Bay) vary as net sinks or sources of phosphorus to Lake Ontario. This thesis aimed to improve our understanding of phosphorus dynamics in these wetlands. Continuous multiparameter sondes (dissolved oxygen, conductivity, turbidity, pH) were deployed above sediments, collecting data …
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Relationships between water quality, species composition, biodiversity and ecosystem function in lakes and flooded pits exposed to uranium mining activities in Northern Saskatechewan
… Ecosystem function variables included planktonic phosphorus cycling and planktonic respiration. The classified lake groups clustered well on ordinations derived from species composition-abundance data suggesting that relationships exist between water quality and plankton species composition. …
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Developing a stable isotope approach to trace the sources and metabolism of phosphorus in freshwaters
… the relative importance of different sources of phosphorus within natural ecosystems. Due to the isotope fractionations that occur alongside metabolism of phosphorus-containing compounds, δ18Op could also be used to better understand the intracellular and extracellular reaction mechanisms that …
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Redox cycling of colloidal macro- and micro-nutrients in a monomictic lake
… bodies as they play an essential role in the cycling of nutrients and carbon, with impacts at the local and global scale. This study selected Lake Ngapouri, a small monomictic lake in the Waikiti Valley, Taupo Volcanic Zone, New Zealand, which receives a considerable amount of nutrients and …
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Quantifying polyphosphate energy for modelling of polyphosphate accumulating organisms behaviour in anaerobic digestors
… experimental observations in AD systems treating phosphorus-rich waste activated sludge, particularly regarding pH predictions and mineral precipitation patterns. The research employed a University of Cape Town membrane bioreactor activated sludge (UCT MBR AS) system to cultivate an enriched PAO …
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Internal Cycling in an Urban Drinking Water Reservoir
The focus of this study was to document phosphorus (P) and metal cycling in the Eagle Creek Reservoir (ECR), located in Indianapolis, central Indiana. Eagle Creek Reservoir serves the drinking water needs of over 80,000 residents. Within the last several years, algal blooms have created stress to …
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Using cover crops to alleviate compaction in organic grain farms
… (TC), nitrate (N-NO3), ammonia (N-NH4), bray phosphorus (P), and pH was determined each sampling time. Additionally, texture and Proctor determinations were conducted once at the beginning of the study. Greater PR and BD values in the CP areas verified compaction; these plots also had …
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Effects of different canopy tree species on belowground biogeochemistry in a wet lowland tropical forest
… I examined how carbon (C), nitrogen (N), and phosphorus (P) cycles vary under canopy tree species – including legume and non-legume species – that vary in foliar leaf nutrient concentrations in a wet tropical forest in southwestern Costa Rica. I found significant differences in belowground C, …
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