The Effects of Dissolved Oxygen on Phosphorus Cycling in Benthic Freshwater Systems

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ISBN 13 :
Total Pages : 99 pages
Book Rating : 4.:/5 (12 download)

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Book Synopsis The Effects of Dissolved Oxygen on Phosphorus Cycling in Benthic Freshwater Systems by : Kathleen R. McCormac-Miller

Download or read book The Effects of Dissolved Oxygen on Phosphorus Cycling in Benthic Freshwater Systems written by Kathleen R. McCormac-Miller and published by . This book was released on 2020 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: The micromaterials were used to treat anoxic lake water and sediment spiked with phosphate adsorbed to goethite in order to determine the effects of oxygen on the release of iron-bound phosphorus into the overlying water through controls on reductive iron dissolution. Systems remained oxygenated for 75-100 hours before returning to anoxic conditions. Evidence of iron dissolution was observed, but the reason as to why was indeterminant. Results indicated that multiple mechanisms were controlling phosphorus speciation and that dissolved oxygen was but one factor affecting phosphorus cycling in the benthic sediments.

Phosphorus Release from Lake Sediments

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ISBN 13 :
Total Pages : 218 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Phosphorus Release from Lake Sediments by : Raymond E. Wildung

Download or read book Phosphorus Release from Lake Sediments written by Raymond E. Wildung and published by . This book was released on 1973 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Riverine Ecosystem Management

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Publisher : Springer
ISBN 13 : 3319732501
Total Pages : 562 pages
Book Rating : 4.3/5 (197 download)

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Book Synopsis Riverine Ecosystem Management by : Stefan Schmutz

Download or read book Riverine Ecosystem Management written by Stefan Schmutz and published by Springer. This book was released on 2018-05-08 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book surveys the frontier of scientific river research and provides examples to guide management towards a sustainable future of riverine ecosystems. Principal structures and functions of the biogeosphere of rivers are explained; key threats are identified, and effective solutions for restoration and mitigation are provided. Rivers are among the most threatened ecosystems of the world. They increasingly suffer from pollution, water abstraction, river channelisation and damming. Fundamental knowledge of ecosystem structure and function is necessary to understand how human acitivities interfere with natural processes and which interventions are feasible to rectify this. Modern water legislation strives for sustainable water resource management and protection of important habitats and species. However, decision makers would benefit from more profound understanding of ecosystem degradation processes and of innovative methodologies and tools for efficient mitigation and restoration. The book provides best-practice examples of sustainable river management from on-site studies, European-wide analyses and case studies from other parts of the world. This book will be of interest to researchers in the field of aquatic ecology, river system functioning, conservation and restoration, to postgraduate students, to institutions involved in water management, and to water related industries.

Clean Coastal Waters

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Publisher : National Academies Press
ISBN 13 : 0309069483
Total Pages : 422 pages
Book Rating : 4.3/5 (9 download)

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Book Synopsis Clean Coastal Waters by : National Research Council

Download or read book Clean Coastal Waters written by National Research Council and published by National Academies Press. This book was released on 2000-08-17 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Environmental problems in coastal ecosystems can sometimes be attributed to excess nutrients flowing from upstream watersheds into estuarine settings. This nutrient over-enrichment can result in toxic algal blooms, shellfish poisoning, coral reef destruction, and other harmful outcomes. All U.S. coasts show signs of nutrient over-enrichment, and scientists predict worsening problems in the years ahead. Clean Coastal Waters explains technical aspects of nutrient over-enrichment and proposes both immediate local action by coastal managers and a longer-term national strategy incorporating policy design, classification of affected sites, law and regulation, coordination, and communication. Highlighting the Gulf of Mexico's "Dead Zone," the Pfiesteria outbreak in a tributary of Chesapeake Bay, and other cases, the book explains how nutrients work in the environment, why nitrogen is important, how enrichment turns into over-enrichment, and why some environments are especially susceptible. Economic as well as ecological impacts are examined. In addressing abatement strategies, the committee discusses the importance of monitoring sites, developing useful models of over-enrichment, and setting water quality goals. The book also reviews voluntary programs, mandatory controls, tax incentives, and other policy options for reducing the flow of nutrients from agricultural operations and other sources.

Canadian Guidance Framework for the Management of Phosphorus in Freshwater Systems

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Publisher : Environment Canada
ISBN 13 :
Total Pages : 136 pages
Book Rating : 4.3/5 (129 download)

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Book Synopsis Canadian Guidance Framework for the Management of Phosphorus in Freshwater Systems by : Canada. National Guidelines and Standards Office

Download or read book Canadian Guidance Framework for the Management of Phosphorus in Freshwater Systems written by Canada. National Guidelines and Standards Office and published by Environment Canada. This book was released on 2004 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presents a guidance framework for the management of phosphorus in freshwater systems. The introduction reviews the development & validation of this framework. Chapter 2 presents a review of the scientific literature on phosphorus in the aquatic environment, including properties, sources, fate, sediment interactions, parameters affecting phosphorus availability, trophic status, & effects on organisms. Chapter 3 examines a number of approaches used by other jurisdictions for setting phosphorus guidelines. Chapter 4 outlines the proposed framework-based approach for phosphorus management in which water bodies are marked for further assessment by comparing their trophic status to predefined ranges of phosphorus concentration. Chapter 5 summarizes some of the recommended assessment options currently use in Canada & other jurisdictions. Chapter 6 reviews management options that can be considered once the phosphorus concentrations have been assessed & compared to original goals for the water body. The final two chapters present case studies of implementation of this framework at Lake Simcoe in Ontario and at Kodiak Lake, Northwest Territories.

Proceedings of the Third International Workshop on Phosphorus in Sediments

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Publisher : Springer Science & Business Media
ISBN 13 : 9401115982
Total Pages : 382 pages
Book Rating : 4.4/5 (11 download)

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Book Synopsis Proceedings of the Third International Workshop on Phosphorus in Sediments by : P.C.M. Boers

Download or read book Proceedings of the Third International Workshop on Phosphorus in Sediments written by P.C.M. Boers and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: This Workshop was organized to assess the status of knowledge on the behaviour of phosphorus in sediments and to define gaps and reassess research strategies, particularly with respect to prevalent methodology and future approach; and to define gaps and reassess research strategies for water management measures in aquatic ecosystems, especially in relation to the release of phosphorus from the sediments and its impact on the functioning of the whole system.

Mechanisms of Internal Phosphorus Loading in Lentic Ecosystems

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ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (137 download)

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Book Synopsis Mechanisms of Internal Phosphorus Loading in Lentic Ecosystems by : Ellen Amara Albright (Ph.D.)

Download or read book Mechanisms of Internal Phosphorus Loading in Lentic Ecosystems written by Ellen Amara Albright (Ph.D.) and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Effective eutrophication management in freshwater ecosystems requires a holistic understanding of internal phosphorus (P) cycling and how nutrient enrichment will interact with other stressors. These management needs inspired the following dissertation research on internal P loading and compounding stressors in shallow lakes, reservoirs, and ponds. Chapter 1 used literature synthesis and meta-analysis to quantify the magnitude and variability of sediment P flux rates across different lentic ecosystems. This analysis synthesized findings across studies to understand patterns between flux rates and both ecosystem- and site-scale drivers. Chapter 2 explored the role of sediment P chemistry as a controlling variable on internal P loading by quantifying spatial heterogeneity in sediment P content and composition within and among lakes. This quantitative understanding of variation in sediment P composition is essential for accurately sampling sediment P pools and inferring likely mechanisms for sediment P release. Building off this understanding of high inter-ecosystem variation in sediment P pools, chapter 3 quantified both seasonal and spatial variation in sediment P pools and fluxes in a temperate reservoir in order to quantify the ecosystem-level impacts of spatiotemporal heterogeneity in internal P loading and identify mechanisms responsible for hot spots of sediment P release. Chapter 4 focused on specific physicochemical mechanisms that may influence sediment P fluxes (i.e., thermal stratification and dissolved oxygen dynamics) and the role of aquatic plants in structuring these drivers. This analysis highlighted that small waterbodies are spatially complex and temporally dynamics systems. Overall, this research has advanced our understanding of lacustrine P cycling by synthesizing our current understanding of internal P loading in lentic ecosystems and by generating knowledge on spatiotemporal variation in sediment P fluxes and the underlying mechanisms.

Comparative Analyses of Ecosystems

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Publisher : Springer Science & Business Media
ISBN 13 : 1461231221
Total Pages : 381 pages
Book Rating : 4.4/5 (612 download)

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Book Synopsis Comparative Analyses of Ecosystems by : Jonathan Cole

Download or read book Comparative Analyses of Ecosystems written by Jonathan Cole and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 381 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arising from the third Cary Conference held in 1989, Comparative Analyses of Ecosystems investigates the utility and limitations of cross-system comparisons in ecology. The contributors, all well-known in their field, support their conclusions on the use and meaning of such comparisons by presenting novel analyses of data utilizing a variety of cross-system approaches in marine, freshwater, and terrestrial systems.

Eutrophication: causes, consequences and control

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Publisher : Springer Science & Business Media
ISBN 13 : 9048196256
Total Pages : 402 pages
Book Rating : 4.0/5 (481 download)

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Book Synopsis Eutrophication: causes, consequences and control by : Abid A. Ansari

Download or read book Eutrophication: causes, consequences and control written by Abid A. Ansari and published by Springer Science & Business Media. This book was released on 2010-10-17 with total page 402 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eutrophication continues to be a major global challenge to water quality scientists. The global demand on water resources due to population increases, economic development, and emerging energy development schemes has created new environmental challenges to global sustainability. Eutrophication, causes, consequences, and control provides a current account of many important aspects of the processes of natural and accelerated eutrophication in major aquatic ecosystems around the world. The connections between accelerated eutrophication and climate change, chemical contamination of surface waters, and major environmental and ecological impacts on aquatic ecosystems are discussed. Water quality changes typical of eutrophication events in major climate zones including temperate, tropical, subtropical, and arid regions are included along with current approaches to treat and control increased eutrophication around the world. The book provides many useful new insights to address the challenges of global increases in eutrophication and the increasing threats to biodiversity and water quality.

Monitoring of Marine Pollution

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Publisher : BoD – Books on Demand
ISBN 13 : 1838808116
Total Pages : 170 pages
Book Rating : 4.8/5 (388 download)

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Book Synopsis Monitoring of Marine Pollution by : Houma Bachari Fouzia

Download or read book Monitoring of Marine Pollution written by Houma Bachari Fouzia and published by BoD – Books on Demand. This book was released on 2019-06-05 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Many of the pollutants discharged into the sea are directly or indirectly the result of human activities. Some of these substances are biodegradable, while others are not. This study is devoted to monitoring areas of the environment. Methods assessment is based on monitoring data and an evaluation of the impact of pollution.Surveillance provides a scientific basis for standards development and application. The methodology of marine pollution control is governed by algorithms and models. A monitoring strategy should be put in place, coupled with an environmental assessment concept, through targeted research activities in areas identified at local and regional levels. This concept will make it possible to diagnose the state of "health" of these zones and consequently to correct any anomalies. Monitoring of the marine and coastal environment is based on recent methods and validated after experiments in the field of marine pollution.

The Benthic Boundary Layer

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Publisher : Oxford University Press
ISBN 13 : 9780199770915
Total Pages : 430 pages
Book Rating : 4.7/5 (79 download)

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Book Synopsis The Benthic Boundary Layer by : Bernard P. Boudreau

Download or read book The Benthic Boundary Layer written by Bernard P. Boudreau and published by Oxford University Press. This book was released on 2001-03-22 with total page 430 pages. Available in PDF, EPUB and Kindle. Book excerpt: The benthic boundary layer is the zone of water and sediment immediately adjacent to the bottom of a sea, lake, or river. This zone is of considerable interest to biologists, geochemists, sedimentologists, and engineers because of very strong gradients of energy, dissolved and solid chemical components, suspended matter, and the number of organisms that live there. It is, for example, the sink for anthropogenic substances and the home of microscopic plant life that provides the nutrients that determine fish populations--and ultimately the size of the fisheries. This book of original chapters edited by Professors Boudreau and Jorgensen, both leading researchers in the field, will meet the need for an up-to-date, definitive text/reference on measurements, techniques, and models for transport and biochemical processes in the benthic boundary layer. Each chapter provides a comprehensive review of a selected field, with illustrated examples from the authors' own work. The book will appeal to professionals and researchers in marine biology, marine chemistry, marine engineering, and sedimentology.

Sediments

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Publisher : CRC Press
ISBN 13 : 1000724212
Total Pages : 432 pages
Book Rating : 4.0/5 (7 download)

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Book Synopsis Sediments by : Renato Baudo

Download or read book Sediments written by Renato Baudo and published by CRC Press. This book was released on 2020-01-31 with total page 432 pages. Available in PDF, EPUB and Kindle. Book excerpt: This important volume-the product of a meeting of a select group of scientists-provides the most recent research results from the world's leaders in the study of toxic pollutants in sediments. It gives practical information on measuring and mapping distributions of concentrations of pollutants and their toxic effects in sediments. Also covered are the use and relative advantages and disadvantages of benthic chambers, sedimentation traps, box corers, "peepers" and other sampling techniques in sediment research and assessment. Important topics covered include: bioassay, elemental speciation, diffuse source problems, nutrient flux, biomethylation, bioavailability, and toxicity assessment. Will help in assessment and monitoring of chemistry, dynamics, bioavailability, and toxicity of pollutants, as well helping to chart courses for remedial action. This book will be of interest to anyone interested in the processes controlling the chemistry and movement of pollutants in sediments, especially: limnologists aquatic toxicologists engineers lake managers ecologists biologists environmental chemists

Nitrogen and Phosphorus in Water

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Publisher :
ISBN 13 :
Total Pages : 152 pages
Book Rating : 4.:/5 (41 download)

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Book Synopsis Nitrogen and Phosphorus in Water by : United States. Division of Water Supply and Pollution Control

Download or read book Nitrogen and Phosphorus in Water written by United States. Division of Water Supply and Pollution Control and published by . This book was released on 1965 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Achieving Nutrient and Sediment Reduction Goals in the Chesapeake Bay

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Publisher : National Academies Press
ISBN 13 : 0309210828
Total Pages : 258 pages
Book Rating : 4.3/5 (92 download)

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Book Synopsis Achieving Nutrient and Sediment Reduction Goals in the Chesapeake Bay by : National Research Council

Download or read book Achieving Nutrient and Sediment Reduction Goals in the Chesapeake Bay written by National Research Council and published by National Academies Press. This book was released on 2011-09-26 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Chesapeake Bay is North America's largest and most biologically diverse estuary, as well as an important commercial and recreational resource. However, excessive amounts of nitrogen, phosphorus, and sediment from human activities and land development have disrupted the ecosystem, causing harmful algae blooms, degraded habitats, and diminished populations of many species of fish and shellfish. In 1983, the Chesapeake Bay Program (CBP) was established, based on a cooperative partnership among the U.S. Environmental Protection Agency (EPA), the state of Maryland, and the commonwealths of Pennsylvania and Virginia, and the District of Columbia, to address the extent, complexity, and sources of pollutants entering the Bay. In 2008, the CBP launched a series of initiatives to increase the transparency of the program and heighten its accountability and in 2009 an executive order injected new energy into the restoration. In addition, as part of the effect to improve the pace of progress and increase accountability in the Bay restoration, a two-year milestone strategy was introduced aimed at reducing overall pollution in the Bay by focusing on incremental, short-term commitments from each of the Bay jurisdictions. The National Research Council (NRC) established the Committee on the Evaluation of Chesapeake Bay Program Implementation for Nutrient Reduction in Improve Water Quality in 2009 in response to a request from the EPA. The committee was charged to assess the framework used by the states and the CBP for tracking nutrient and sediment control practices that are implemented in the Chesapeake Bay watershed and to evaluate the two-year milestone strategy. The committee was also to assess existing adaptive management strategies and to recommend improvements that could help CBP to meet its nutrient and sediment reduction goals. The committee did not attempt to identify every possible strategy that could be implemented but instead focused on approaches that are not being implemented to their full potential or that may have substantial, unrealized potential in the Bay watershed. Because many of these strategies have policy or societal implications that could not be fully evaluated by the committee, the strategies are not prioritized but are offered to encourage further consideration and exploration among the CBP partners and stakeholders.

Selected Water Resources Abstracts

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Publisher :
ISBN 13 :
Total Pages : 884 pages
Book Rating : 4.3/5 (91 download)

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Book Synopsis Selected Water Resources Abstracts by :

Download or read book Selected Water Resources Abstracts written by and published by . This book was released on 1991 with total page 884 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Marine Carbon Biogeochemistry

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Publisher : Springer
ISBN 13 : 3030108228
Total Pages : 118 pages
Book Rating : 4.0/5 (31 download)

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Book Synopsis Marine Carbon Biogeochemistry by : Jack J. Middelburg

Download or read book Marine Carbon Biogeochemistry written by Jack J. Middelburg and published by Springer. This book was released on 2019-01-25 with total page 118 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book discusses biogeochemical processes relevant to carbon and aims to provide readers, graduate students and researchers, with insight into the functioning of marine ecosystems. A carbon centric approach has been adopted, but other elements are included where relevant or needed. The book focuses on concepts and quantitative understanding of primary production, organic matter mineralization and sediment biogeochemistry. The impact of biogeochemical processes on inorganic carbon dynamics and organic matter transformation are also discussed.

Interactions of Phosphate and Silicate with Iron Oxides in Freshwater Environments

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Publisher :
ISBN 13 :
Total Pages : 206 pages
Book Rating : 4.:/5 (112 download)

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Book Synopsis Interactions of Phosphate and Silicate with Iron Oxides in Freshwater Environments by : Md Abdus Sabur

Download or read book Interactions of Phosphate and Silicate with Iron Oxides in Freshwater Environments written by Md Abdus Sabur and published by . This book was released on 2019 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Internal phosphorus loads, from bottom sediments to surface waters, are often comparable in magnitude to external phosphorus loads, particularly in water bodies with a history of high external phosphorus inputs from point and non-point sources. The benthic release of phosphorus can be influenced by several factors including pH, redox potential, temperature, microbial activity and the concentration of competitive anions at or near the sediment-water interface. Dissolved silicate occurs ubiquitously in natural waters and may act as a competitive ion to phosphate. Nonetheless, prior to the work in this thesis, the effect of silicate on internal phosphorus loading remained poorly understood. This thesis addresses several of the mechanisms through which silicate may influence the mobilization of aqueous phosphate from sediments in aquatic environments. The thesis starts with a thorough literature review of phosphorus biogeochemical cycling in relation to eutrophication, sediment-surface water interactions, mineralogy, competitive anions and microbial activity (Chapter 1). Next, adsorption/desorption of phosphate on/from goethite, a model ferric (hydr)oxide mineral, is investigated in the absence and presence of dissolved silicate. The influence of dissolved silicate on phosphate adsorption is evaluated through laboratory experiments and application of the CD-MUSIC model (Chapter 2). The results show that increasing concentrations of silicate decrease phosphate adsorption, leaving more phosphate in the aqueous phase. The competitive effect of dissolved silicate is more pronounced under alkaline conditions. Subsequently, phosphate desorption experiments were conducted under dynamic pH conditions in the presence and absence of silicate (Chapter 3). The experimental results show that the gradual transition from acidic to alkaline conditions induces the desorption of phosphate adsorbed to goethite under acidic conditions. The presence of silicate in the phosphate/goethite system does not affect phosphate desorption, because of the stronger surface complexation of phosphate to goethite. In addition to adsorption and desorption processes, the co-precipitation of phosphate with iron and the potential subsequent dissolution of these co-precipitates as a result of changing physico-chemical conditions may also control the mobility of phosphate in aquatic environments. The effects of dissolved silicate on the co-precipitation of phosphate with iron and the reactivity of the resulting solids are examined (Chapter 4). Ferric (co)-precipitates (i.e., Fe-P-Si) with variable Si:Fe ratios, were synthesized either via oxidation of Fe2+(aq) or by increasing the pH of Fe3+(aq) solution. The solids were characterized by a combination of chemical and spectroscopic techniques including attenuated total internal reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray powder diffraction spectroscopy (XRD). Similar solid phase P:Fe ratios were found in co-precipitates formed from solutions with different dissolved silicate concentrations, regardless of the method of preparation. This suggests that the interactions between phosphate and iron during co-precipitation were not affected by dissolved silicate. The ferric (co)-precipitates were subsequently reductively dissolved abiotically in buffered ascorbate-citrate solution to determine their reactivity under reducing conditions. The kinetic data show that the co-precipitates with higher Si:Fe ratios were more recalcitrant to dissolution. For co-precipitates synthesized via oxidation of Fe2+(aq), reductive dissolution experiments were also conducted in the presence of the facultative anaerobic iron reducing bacteria Shewanella putrefaciens. XRD analyses of the residual solids imply that solids with the higher Si:Fe ratios may be more resistant to microbially mediated reductive dissolution. The relative reactivities of the co-precipitates obtained by the two synthesis methods are also addressed in Chapter 4. In Chapter 5, the effect of silicate on the mobility of phosphate in a natural sediment was evaluated via flow-through experiments. The results show that dissolved silicate enhances the mobility of phosphate at the sediment-water interface. Ferric (co)-precipitates were formed at the oxic surface of sediment columns via the oxidation of ferrous iron supplied with upflowing solutions containing variable silicate concentrations. The subsequent dissolution of these co-precipitates under imposed anoxic conditions at the sediment-water interface indicates that the co-precipitates formed at higher dissolved silicate concentrations were more reactive towards reductive dissolution. These results are therefore in apparent contradiction to those observed in Chapter 4. The ferric (co)-precipitates (i.e., Fe-P-Si) evaluated in Chapter 4 were prepared from solutions containing high concentrations of iron, phosphate and silicate, by imposing either rapid aeration or pH increase. These conditions were selected to maximize the yield from the syntheses. The synthesis methods in Chapter 4 are therefore most representative of aquatic environments where co-precipitation occurs rapidly (e.g., groundwater springs) and the concentrations of these dissolved constituents are fairly high. However, in many other aquatic environments, the diffusion-controlled release of Fe2+(aq) from the deeper sediments results in the gradual oxidation of Fe2+ at the sediment-water interface under oxic conditions. This process is typical in lake sediments with minimal advective exchange between surface water and groundwater. This gradual oxidation (at relatively low concentrations of Fe2+) results in the slow formation of ferric (co)-precipitates which may be dissimilar to those synthesized herein and discussed in Chapter 4. The ferric (co)-precipitates synthesized with the flow-through column system in Chapter 5 may be better analogues of slow forming co-precipitates in diffusion dominated or moderately advection influenced aquatic sediments than those synthesized in Chapter 4. Finally, to elucidate the likely importance of the various influences of dissolved silicate on phosphate mobility investigated in this thesis, concentrations of dissolved phosphate and silicate as well as pH data are extracted from the US National Water Information System (NWIS) network (data shown in Chapter 1 and Chapter 2). The NWIS data along with combined experimental and modeling results suggest that silicate-mediated phosphate mobilization is likely a commonly occurring process at the sediment-water interface of lakes and reservoirs. This thesis also demonstrates the multiple roles of silicate on the mobilization of phosphate in aquatic environments, and improves our fundamental knowledge of iron, phosphorus and silicon cycling in freshwater environments.