Physical Sciences and Mathematics Commons^™

Iron-Sulfide And Trace Element Behaviour In Sediments Of Coombabah Lake, Moreton Bay (Australia), Edward Burton, Leigh Sullivan, Richard Bush, Bernard Powell

Associate Professor Edward D Burton

No abstract provided.

Sludge-Derived Cu And Zn In A Humic-Gley Soil: Effect Of Dissolved Metal-Organic Matter Complexes On Sorption And Partitioning, Edward Burton, Darryl Hawker, M Redding

Associate Professor Edward D Burton

A sequential extraction scheme was combined with sorption isotherm analysis in order to investigate sorption of sewage sludge-derived Cu and Zn to the A-horizon of a humic-gley soil as a whole, and to the operationally defined exchangeable (1 M MgCl₂), carbonate (1 M NaOAc), Fe/Mn oxide (0.04 M NH₂OH.HCl), and organic (0.02 M HNO₃+30% H₂O₂) soil fractions. Sorption parameters were compared for a sample of sludge leachate (with 97.4% of Cu and 63.2% of Zn present as dissolved metal-organic matter complexes, as calculated by geochemical modelling involving MINTEQA2 and verified …

Factors Controlling The Geochemical Partitioning Of Trace Metals In Estuarine Sediments, Edward Burton, Ian Phillips, Darryl Hawker

Associate Professor Edward D Burton

The geochemical partitioning of trace metals in sediments is of great importance in risk assessment and remedial investigation. Selected factors that may control the partitioning behavior of Cu, Pb and Zn in non-sulfidic, estuarine sediments were examined with the use of combined sorption curve—sequential extraction analysis. This approach, which has not been previously used to examine estuarine sediments, allowed determination of sorption parameters for Cu, Pb and Zn partitioning to individual geochemical fractions. Partitioning behavior in sulfidic sediments was also determined by sequentially extracting Cu, Pb, and Zn from synthetic sulfide minerals and from natural sediment and pure quartz sand …

Sorption And Desorption Behaviour Of Tributyltin With Natural Sediments, Edward Burton, Ian Phillips, Darryl Hawker

Associate Professor Edward D Burton

Tributyltin (TBT) sorption to four natural sediment samples in artificial seawater was examined under a range of modified pH and salinity conditions. Three of the sediment samples were relatively pristine with regard to TBT contamination, but the fourth was a TBT-contaminated sediment from a commercial marina. Sorption of TBT was described well by linear sorption isotherms, with distribution coefficients ranging from 6.1 to 5210 L/kg depending on the pH and salinity. The sediment organic C content and particle size distribution were important determinants of sorption behavior. The presence of resident TBT in the contaminated marina sediment caused a substantial reduction …

Tributyltin Partitioning In Sediments: Effect Of Aging, Edward Burton, Ian Phillips, Darryl Hawker

Associate Professor Edward D Burton

The effect of aging on the solid/pore-water partitioning and desorption behaviour of tributyltin (TBT) in sediments was examined. Three sediment samples with contrasting physical and chemical properties were spiked with 10 mg/kg TBT and aged under sterile conditions for periods of time ranging from 1 to 84 days. Aging had a negligible effect on partitioning and desorption behaviour in a sandy sample with very low organic carbon content (0.2% w/w). In contrast, for samples with larger amounts of organic carbon (2.6% and 4.8% w/w), aging caused substantial increases in TBT sorption. For these samples, apparent distribution coefficients (KD,app) obtained from …

Fractionation And Extractability Of Sulfur, Iron And Trace Elements In Sulfidic Sediments, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

This study describes iron and sulfur fractionation, and the related extractability of selected trace elements (As, Cd, Cr, Cu, Ni, Pb and Zn) in estuarine sediments. The sediments were sulfidic, with moderately high concentrations of pore-water sulfide (200–600 μmol l−1) and acid-volatile sulfide (AVS; 9.9–129 μmol g−1). Pyrite-S concentrations increased with depth, with 63–251 μmol g−1 at site W1 and 312–669 μmol g−1 at site W2. The degree of sulfidisation was generally high (>80%), indicating that Fe may be limiting pyrite accumulation. The ratios of AVS to pyrite-S increased with sediment depth, as expected for the pyritisation of solid-phase …

Acid-Volatile Sulfide Oxidation In Coastal Floodplain Drains: Iron-Sulfur Cycling And Effects On Water Quality, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

The effect of acid-volatile sulfide (AVS) oxidation on Fe-S cycling and water quality in coastal flood plain drains from acid-sulfate soil landscapes was examined using natural sediments and synthetic iron monosulfide. Oxidation of AVS occurred rapidly (half-time ≤ 1 h) and produced elemental sulfur (S80(s)) and iron oxyhydroxide (FeOOH(s)). The initial rapid AVS oxidation process occurred without significant acidification or changes to the aqueous-phase composition. Severe acidification (pH < 4) occurred only once S80(s) began to oxidize to SO4 (within 2-3 days of the initial AVS oxidation). Our results demonstrate, for the first time with natural sediments, a significant pH-buffered (near-neutral) …

Sedimentary Iron Geochemistry In Acidic Waterways Associated With Coastal Lowland Acid Sulfate Soils, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

We examined the solubility, mineralogy and geochemical transformations of sedimentary Fe in waterways associated with coastal lowland acid sulfate soils (CLASS). The waterways contained acidic (pH 3.26–3.54), FeIII-rich (27–138 μM) surface water with low molar Cl:SO4 ratios (0.086–5.73). The surficial benthic sediments had high concentrations of oxalate-extractable Fe(III) due to schwertmannite precipitation (kinetically favoured by 28–30% of aqueous surface water Fe being present as the FeIIISO4 species). Subsurface sediments contained abundant pore-water HCO3 (6–20 mM) and were reducing (Eh < −100 mV) with pH 6.0–6.5. The development of reducing conditions caused reductive dissolution of buried schwertmannite and goethite (formed via in situ transformation of schwertmannite). As a consequence, pore-water FeII concentrations were high (>2 mM) and were constrained by precipitation–dissolution of siderite. The near-neutral, reducing conditions also promoted SO4-reduction and the formation of acid-volatile …

Effects Of Diffusion And Resuspension On Nutrient Release From Submerged Sediments, Ian Phillips, Edward Burton, Darryl Hawker

Associate Professor Edward D Burton

Nutrient release from a coarse-sand (CS) and a fine-sand (FS) estuarine sediment into the overlying water column was studied under static (diffusion-controlled) and dynamic (resuspension) conditions. Resuspension increased the amounts of NH4+, NO3- and P released from the sediment cores compared to those released by diffusion alone due to direct release of these nutrients from the readily available pore-water and ion exchange fractions. The average effective NH4+, NO3- and P diffusion coefficients (De) were found to be similar for both sediments, and did not vary significantly between static and dynamic conditions. Values of De were typically of the order of …

Effects Of Ph And Salinity On Copper, Lead And Zinc Sorption Rates In Sediments From Moreton Bay, Australia, Ian Phillips, Dane Lamb, Darryl Hawker, Edward Burton

Associate Professor Edward D Burton

No abstract provided.

Schwertmannite Transformation To Goethite Via The Fe(Ii) Pathway: Reaction Rates And Implications For Iron-Sulfide Formation, Edward Burton, Richard Bush, Leigh Sullivan, David Mitchell

Associate Professor Edward D Burton

Schwertmannite (Fe8O8(OH)6SO4) is a common Fe(III)-oxyhydroxysulfate mineral in acid-sulfate systems, where its formation and fate strongly influence water quality. The present study examines transformation of schwertmannite to goethite (FeOOH), as catalyzed by interactions with Fe(II) in anoxic aquatic environments. This study also evaluates the role of the Fe(II) pathway in influencing the formation of iron–sulfide minerals in such environments. At pH > 5, the rates of Fe(II)-catalyzed schwertmannite transformation were several orders of magnitude faster than transformation in the absence of Fe(II). Complete transformation of schwertmannite occurred within only 3–5 h at pH > 6 and Fe(II)(aq) 5 mmol L−1. Model calculations …

Trace Metals And Nutrients In Bottom Sediments Of The Southport Broadwater, Australia, Edward Burton, Ian Phillips, Darryl Hawker

Associate Professor Edward D Burton

No abstract provided.

Estimating Sludge Loadings To Land Based On Trace Metal Sorption In Soil: Effect Of Dissolved Organo-Metallic Complexes, Edward Burton, Darryl Hawker, M Redding

Associate Professor Edward D Burton

This paper describes the results of research examining the effect of dissolved organo-metallic complexes of copper (Cu) and zinc (Zn) from sewage sludge leachate on sorption by a humic-gley soil A-horizon, and the influence of such complexes on resultant sludge loading estimates. Sorption was described with Linear, Freundlich or Langmuir equations, and compared between a sample of sludge leachate (containing 97.4% of Cu and 63.2% of Zn as dissolved organo-metallic complexes) and a reference solution (which mimicked the leachate, except for a lack of dissolved organic material). This comparison revealed that dissolved organo-metallic complexes significantly depressed Cu and Zn sorption …

A Microwave Digestion Technique For The Extraction Of Fossil Diatoms From Coastal Lake And Swamp Sediments, Jeffrey Parr, Kathryn Taffs, Christopher Lane

Jeffrey Parr

This study provides an introduction to a microwave digestion technique for the extraction of fossil diatoms from sediments. The microwave technique is compared with the standard diatom extraction technique of Battarbee (Diatom analysis. In: Berglund B.E. (ed.), Handbook of Holocene Palaeoecology and Palaeohydrology. John Wiley and Sons) that uses a combination of dilute hydrochloric acid and hydrogen peroxide and the advantages and disadvantages of their use are discussed. The results suggest that the microwave technique is fast, inexpensive and most importantly produces replicable fossil diatom assemblage data. Small samples sizes are used (0.3 g) for the microwave method thus lower …

Fires And Their Implications For Acidic Peatlands, Northeastern Nsw, Jeffrey Parr, Kathryn Taffs, Geoffrey Kerr, J Arthur

Jeffrey Parr

No abstract provided.

Interactions Between Human Activity, Volcanic Eruptions And Vegetation During The Holocene At Garua And Numundo, West New Britain, Png, William Boyd, Carol Lentfer, Jeffrey Parr

Jeffrey Parr

This paper reviews recent fossil phytolith analysis from wet tropical West New Britain (Papua New Guinea). The Holocene vegetation has been influenced by spatially and temporally diverse patterns of both prehistoric human settlement and catastrophic volcanic events. We have hypothesized different landscape responses and recovery pathways to events during the last six millennia. Phytolith sequences on the coastal lowlands, the Willaumez Peninsula, and nearby island of Garua provide details of vegetational change and human interactions at different landscape scales since c. 5900 cal yr B.P. During this period four major volcanic eruptions (c. 5900, 3600, 1700 and 1400 cal yr …

Chronology And Palaeoecology Of An Acidic Wetland Peat In Northeastern Nsw, Kathryn Taffs, Jeffrey Parr, Keith Bolton

Jeffrey Parr

No abstract provided.

Reconstructing Fire Histories: Methods, Interpretation And Common On-Ground Across Fire History Research In Australia, Jeffrey Parr, Geoffrey Kerr, J Arthur, Keith Bolton, Geraldine Jacobsen, Kathryn Taffs

Jeffrey Parr

No abstract provided.

Response To Cotter And Cotter: Confirming The Probable Industrial Origin Of Archaeological Daub At An Iron Age Site In Northeast Thailand, William Boyd, Jeffrey Parr

Jeffrey Parr

No abstract provided.

Fires Impact On An Acidic Peatland In Northeastern Nsw: Implications For The Interpretation Of Fire Histories, Pyrite Formation And Loss Of Organic Carbon, Jeffrey Parr, Geoffrey Kerr, J Arthur, Kathryn Taffs

Jeffrey Parr

No abstract provided.

West Byron Wetland Vegetation History Report., Jeffrey Parr, Kathryn Taffs

Jeffrey Parr

No abstract provided.

Interregional Comparison Of Karst Disturbance: West-Central Florida And Southeast Italy, Leslie North

Leslie North

Sustainable Trends Offer Reason For Hope In Pennsylvania And Nation, John Dernbach

John C. Dernbach

No abstract provided.

Sustainable America Is Achievable In Our Lifetime, John Dernbach

John C. Dernbach

No abstract provided.

Smart Use Of Resources Makes Good Economic Sense, John Dernbach

John C. Dernbach

No abstract provided.

Quantitative Assessment Of Climate-Induced Glacier Fluctuation In The Central Himalaya Utilizing Satellite Images., Umesh Haritashya

Umesh Haritashya

Sustainability, Energy, and Environment Seed Grant. Total Amount $10,000. Role: PI. Project duration: January 1, 2009 – December 31, 2009.

Quantitative Paleobiogeography Unraveling Macroevolutionary Patterns In Fossil Plankton Using Geographic Information Systems (Gis) Software And The New Geobiodiversity Database, Daniel Goldman

Daniel Goldman

Funding agency: UDRI Seed Grant Amount: $7,500.00

Hierarchical Modeling: Biogeochemical Processes And Mechanisms That Drives Clay Nano- And Microfabric Development, Kenneth J. Curry, Richard H. Bennett, Paula J. Smithka, Matthew H. Hulbert

Kenneth J. Curry

Conceptual scientific models of clay and clay fabric development can be constructed profitably by considering chemical and physical systems in terms of an ordered hierarchy. We develop here a hierarchical model of early stages of marine sediment development identifying processes and focusing on mechanisms. While the focus of our model is on mechanisms, the physical aspects of the hierarchy are cast in terms of the scale of structure in which the mechanisms occur. Our primary scale of interest is the nanometer (nanofabric) level of organization of sediment fabric. This level is nested below the micrometer (microfabric) level that includes aggregates …