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Iron Behavior In A Northern Estuary: Large Pools Of Non-Sulfidized Fe(Ii) Associated With Organic Matter, Changxun Yu, Joonas J. Virtasalo, Torbjörn Karlsson, Pasi Peltola, Peter Österholm, Edward D. Burton, Laura Arppe, Johan K. Hogmalm, Antti E K Ojala, Mats E. Aström Apr 2016

Iron Behavior In A Northern Estuary: Large Pools Of Non-Sulfidized Fe(Ii) Associated With Organic Matter, Changxun Yu, Joonas J. Virtasalo, Torbjörn Karlsson, Pasi Peltola, Peter Österholm, Edward D. Burton, Laura Arppe, Johan K. Hogmalm, Antti E K Ojala, Mats E. Aström

Associate Professor Edward D Burton

The estuaries of the Northern Baltic Sea (Gulf of Bothnia) receive an abundance of diagenetically reactive catchment-derived Fe, which is to a large degree complexed with organic matter or present as Fe (hydr-)oxides. However, our understanding of sedimentary Fe diagenesis in these estuaries is limited. To address this limitation, the present study examines Fe geochemistry in a 3.5-m-thick estuarine benthic mud layer and three samples of suspended particulate matter of a catchment on the eastern Gulf of Bothnia. The age–depth model of the mud, constructed on the basis of sedimentary features as well as 137Cs and aquatic plant 14 …


Arsenic Solid-Phase Speciation In An Alluvial Aquifer System Adjacent To The Himalayan Forehills, Nepal, Scott Johnston, Jasmine Diwakar, Edward Burton Jan 2016

Arsenic Solid-Phase Speciation In An Alluvial Aquifer System Adjacent To The Himalayan Forehills, Nepal, Scott Johnston, Jasmine Diwakar, Edward Burton

Associate Professor Edward D Burton

Alluvial aquifers contaminated by geogenic arsenic often lack direct solid-phase speciation data, hindering efforts to understand landscape-scale spatial heterogeneity and controls on As mobility. Here, we examine solid-phase As and Fe speciation of alluvial aquifer, river and hyporheic-seep sediments along a topographic gradient at the Himalayan foothills/upper-Ganges floodplain margin. We employ a combination of X-ray absorption spectroscopy, selective extracts, electron microscopy and X-ray fluorescence. Source-river sediments were found to contain a mixture of solid-phase As(V) and As(III) species, while vertically heterogeneous bore-hole sediments also contained a solid-phase As-sulfide species. In general, the abundance of reduced As species [As(III) + As-sulfide] …


Sulfur, Iron And Carbon Cycling Following Hydrological Restoration Of Acidic Freshwater Wetlands, Scott Johnston, Edward Burton, Thor Aaso, Gerard Tuckerman Sep 2015

Sulfur, Iron And Carbon Cycling Following Hydrological Restoration Of Acidic Freshwater Wetlands, Scott Johnston, Edward Burton, Thor Aaso, Gerard Tuckerman

Associate Professor Edward D Burton

Freshwater re-flooding is a relatively novel approach to remediate drained acid sulfate soil (ASS) wetlands. This study documents the geochemical consequences of restoring freshwater re-flooding for contemporary reduced inorganic sulfur (RIS) and iron species in two coastal floodplain ASS wetlands. Re-flooding has established predominantly reducing/suboxic conditions and encouraged organic carbon accumulation in surface sediments (~ 20–30%). The pH of former sulfuric horizons has increased by ~ 2–3 units, partly in response to alkalinity generation from anaerobic metabolism of organic carbon coupled with Fe(III) and SO42 − reduction. Despite considerable sulfidisation, reactive Fe (FeR; sum of 1 M HCl and citrate–dithionite …


Modifications To The Classification Of Acid Sulfate Soil Material, Leigh Sullivan, R Fitzpatrick, Richard Bush, Edward Burton, P Shand, Nicholas Ward Oct 2013

Modifications To The Classification Of Acid Sulfate Soil Material, Leigh Sullivan, R Fitzpatrick, Richard Bush, Edward Burton, P Shand, Nicholas Ward

Associate Professor Edward D Burton

No abstract provided.


Reflooding The Exposed And Acidified Lower Lakes Sediments: Seawater Or River Murray Water, Leigh Sullivan, Richard Bush, Edward Burton, Nicholas Ward, L Barnett, L Mosley, R Seaman Oct 2013

Reflooding The Exposed And Acidified Lower Lakes Sediments: Seawater Or River Murray Water, Leigh Sullivan, Richard Bush, Edward Burton, Nicholas Ward, L Barnett, L Mosley, R Seaman

Associate Professor Edward D Burton

No abstract provided.


Lower Lakes Laboratory Study Of Contaminant Mobilisation Under Seawater And Freshwater Inundation (Long-Term Study), Leigh Sullivan, Richard Bush, Nicholas Ward, Diane Fyfe, M Johnston, Edward Burton, Paul Cheeseman, Michelle Bush, Crystal Maher, Michael Cheetham, K Watling, Vanessa Wong, R Maher, E Weber Oct 2013

Lower Lakes Laboratory Study Of Contaminant Mobilisation Under Seawater And Freshwater Inundation (Long-Term Study), Leigh Sullivan, Richard Bush, Nicholas Ward, Diane Fyfe, M Johnston, Edward Burton, Paul Cheeseman, Michelle Bush, Crystal Maher, Michael Cheetham, K Watling, Vanessa Wong, R Maher, E Weber

Associate Professor Edward D Burton

No abstract provided.


Bioremediation Of Acidic Lake-Bed Sediments Via Enhanced In-Situ Sulfate-Reduction: Lower Lakes, South Australia, Edward Burton, Leigh Sullivan, R Seaman, L Barnett, L Mosley, Nicholas Ward, Paul Cheeseman, Trent Mcintyre Oct 2013

Bioremediation Of Acidic Lake-Bed Sediments Via Enhanced In-Situ Sulfate-Reduction: Lower Lakes, South Australia, Edward Burton, Leigh Sullivan, R Seaman, L Barnett, L Mosley, Nicholas Ward, Paul Cheeseman, Trent Mcintyre

Associate Professor Edward D Burton

No abstract provided.


Study Of Monosulfidic Black Ooze (Mbo) In The Geographe Bay Area, Western Australia, Nicholas Ward, Richard Bush, Leigh Sullivan, Edward Burton, Paul Cheeseman Oct 2013

Study Of Monosulfidic Black Ooze (Mbo) In The Geographe Bay Area, Western Australia, Nicholas Ward, Richard Bush, Leigh Sullivan, Edward Burton, Paul Cheeseman

Associate Professor Edward D Burton

No abstract provided.


Lower Lakes Sulfate Reduction Study (Interim Report), Leigh Sullivan, Edward Burton, Nicholas Ward, Richard Bush, J Coughran, Diane Fyfe, Paul Cheeseman, Trent Mcintyre Oct 2013

Lower Lakes Sulfate Reduction Study (Interim Report), Leigh Sullivan, Edward Burton, Nicholas Ward, Richard Bush, J Coughran, Diane Fyfe, Paul Cheeseman, Trent Mcintyre

Associate Professor Edward D Burton

No abstract provided.


Lower Lakes Sulfate Reduction Study, Leigh Sullivan, Edward Burton, Nicholas Ward, Richard Bush, J Coughran, Michael Cheetham, Diane Fyfe, Paul Cheeseman, Trent Mcintyre Oct 2013

Lower Lakes Sulfate Reduction Study, Leigh Sullivan, Edward Burton, Nicholas Ward, Richard Bush, J Coughran, Michael Cheetham, Diane Fyfe, Paul Cheeseman, Trent Mcintyre

Associate Professor Edward D Burton

No abstract provided.


The Classification Of Acid Sulfate Soil Materials: Further Modifications, Leigh Sullivan, R Fitzpatrick, Richard Bush, Edward Burton, P Shand, Nicholas Ward Oct 2013

The Classification Of Acid Sulfate Soil Materials: Further Modifications, Leigh Sullivan, R Fitzpatrick, Richard Bush, Edward Burton, P Shand, Nicholas Ward

Associate Professor Edward D Burton

No abstract provided.


Acid Sulfate Soils: Their Characteristics, Risk Assessment, And Management Options, Leigh Sullivan, Richard Bush, Edward Burton Sep 2013

Acid Sulfate Soils: Their Characteristics, Risk Assessment, And Management Options, Leigh Sullivan, Richard Bush, Edward Burton

Associate Professor Edward D Burton

No abstract provided.


Sea-Level Rise Impacts On Coastal Water Quality: Interactions Between Porewater, Surfaceand Shallow Groundwater Geochemistry, Vanessa Wong, Scott Johnston, Phillip Hirst, Edward Burton, Richard Bush, Leigh Sullivan, Peter Slavich Aug 2013

Sea-Level Rise Impacts On Coastal Water Quality: Interactions Between Porewater, Surfaceand Shallow Groundwater Geochemistry, Vanessa Wong, Scott Johnston, Phillip Hirst, Edward Burton, Richard Bush, Leigh Sullivan, Peter Slavich

Associate Professor Edward D Burton

No abstract provided.


The Effects Of Increasing Salinity On Exchange Processes In Coastal Lowland Acid Sulfate Soils, Vanessa Wong, Scott Johnston, Richard Bush, Leigh Sullivan, Edward Burton, Peter Slavich Aug 2013

The Effects Of Increasing Salinity On Exchange Processes In Coastal Lowland Acid Sulfate Soils, Vanessa Wong, Scott Johnston, Richard Bush, Leigh Sullivan, Edward Burton, Peter Slavich

Associate Professor Edward D Burton

10 coastal lowland acid sulfate soils (CLASS) from floodplains in eastern Australia were subjected to increasing seawater concentrations to determine the effects of exchange processes on metal desorption due to increasing ionic strength. Soils were subjected to one of six treatments; 0%, 10%, 20%, 50%, 80% or 100% seawater diluted in deionised water. pH decreased with increasing seawater concentration. In general, concentrations of Al, Cd, Fe2+ and Mn increased in soils sampled from levees, organic and mineral sulfuric horizons with increasing salinity. Increasing trace metal concentrations with increasing seawater concentration is attributed to both exchange processes and pH effects. The …


Hydrological Controls On Acid Generation And Export In Floodplain Wetlands, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan Jul 2013

Hydrological Controls On Acid Generation And Export In Floodplain Wetlands, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

No abstract provided.


As, Fe And S Cycling During Reductive Biomineralisation Of Pedogenic Jarosite, Annabelle Keene, Scott Johnston, Edward Burton, Richard Bush Jul 2013

As, Fe And S Cycling During Reductive Biomineralisation Of Pedogenic Jarosite, Annabelle Keene, Scott Johnston, Edward Burton, Richard Bush

Associate Professor Edward D Burton

No abstract provided.


The Role Of Microbial Sulfidogenesis In Shaping Iron-Sulfur-Arsenic Interactions Within Floodplain Soils, Edward Burton, Scott Johnston, Richard Bush Jul 2013

The Role Of Microbial Sulfidogenesis In Shaping Iron-Sulfur-Arsenic Interactions Within Floodplain Soils, Edward Burton, Scott Johnston, Richard Bush

Associate Professor Edward D Burton

No abstract provided.


Assessing Acid Sulfate Soil Neutralising Capacity: A New Approach, Leigh Sullivan, K Watling, Salirian Claff, Richard Bush, Edward Burton, Scott Johnston, C Ahern, A Mcelnea Jul 2013

Assessing Acid Sulfate Soil Neutralising Capacity: A New Approach, Leigh Sullivan, K Watling, Salirian Claff, Richard Bush, Edward Burton, Scott Johnston, C Ahern, A Mcelnea

Associate Professor Edward D Burton

No abstract provided.


A New Method To Rapidly And Accurately Map Acid Sulfate Soils: Exploring The Utility Of An Em38, Vanessa Wong, J Triantafilis, Scott Johnston, T Nhan, Leigh Sullivan, Richard Bush, Edward Burton, Peter Slavich, P Hirst Jul 2013

A New Method To Rapidly And Accurately Map Acid Sulfate Soils: Exploring The Utility Of An Em38, Vanessa Wong, J Triantafilis, Scott Johnston, T Nhan, Leigh Sullivan, Richard Bush, Edward Burton, Peter Slavich, P Hirst

Associate Professor Edward D Burton

No abstract provided.


Hydro-Geochemical Coupling In Seawater Inundated Acid Sulfate Soils: Mobilisation Of Arsenic And Hysteresis In Iron And Sulfur Cycling, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan Jul 2013

Hydro-Geochemical Coupling In Seawater Inundated Acid Sulfate Soils: Mobilisation Of Arsenic And Hysteresis In Iron And Sulfur Cycling, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

No abstract provided.


Reductive Biomineralisation Of Pedogenic Jarosite In Tidally Inundated Acid Sulfate Soils, Annabelle Keene, Scott Johnston, Edward Burton, Richard Bush, Leigh Sullivan Jul 2013

Reductive Biomineralisation Of Pedogenic Jarosite In Tidally Inundated Acid Sulfate Soils, Annabelle Keene, Scott Johnston, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

No abstract provided.


A Critical Evaluation Of Retained Acidity (Ar) Estimating Methods In Acid Base Account (Aba) Approach For Acid Sulfate Soils (Ass), Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton May 2013

A Critical Evaluation Of Retained Acidity (Ar) Estimating Methods In Acid Base Account (Aba) Approach For Acid Sulfate Soils (Ass), Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton

Associate Professor Edward D Burton

No abstract provided.


Understanding The Behaviour Of Schwertmannite And Jarosite In Acid Sulfate Soils, Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton May 2013

Understanding The Behaviour Of Schwertmannite And Jarosite In Acid Sulfate Soils, Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton

Associate Professor Edward D Burton

No abstract provided.


Readily Available Acidity In Schwertmannite, Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton May 2013

Readily Available Acidity In Schwertmannite, Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton

Associate Professor Edward D Burton

Schwertmannite and jarosite are considered as less soluble ironhydroxy sulfate minerals which are present in highly acidic environments (pH < 3). These minerals release acidity in the long run as they weather by hydrolysis [1]. However, 1M KCl extraction of soil samples (Clarence and Quartz) spiked with those two minerals showed that schwertmannite has some acidity that may be readily available.


Underestimation Of Retained Acidity Measured Using Chromium Suite In Acid Sulfate Soils Containing Schwermannite And Jarosite, Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton May 2013

Underestimation Of Retained Acidity Measured Using Chromium Suite In Acid Sulfate Soils Containing Schwermannite And Jarosite, Chamindra Vithana, Leigh Sullivan, Richard Bush, Edward Burton

Associate Professor Edward D Burton

No abstract provided.


Hydro-Geochemical Coupling In Seawater Inundation Acid Sulfate Soils: Mobilisation Of Arsenic And Hysteresis In Iron And Sulfur Cycling, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan May 2013

Hydro-Geochemical Coupling In Seawater Inundation Acid Sulfate Soils: Mobilisation Of Arsenic And Hysteresis In Iron And Sulfur Cycling, Scott Johnston, Annabelle Keene, Edward Burton, Richard Bush, Leigh Sullivan

Associate Professor Edward D Burton

A large-scale field trial indicates that tidal seawater inundation of coastal acid sulfate soils (CASS) stimulates iron and sulfate reducing conditions, leading to the generation of internal alkalinity and greatly decreasing soil / groundwater acidity. This remediation technique can be considered highly effective from the relatively narrow perspective of decreasing acidity and raising pH. However, a broader perspective reveals that tidal seawater inundation initiates complex and tightly coupled hydrological and geochemical processes within sediments and porewaters. These processes have had a profound effect on the mobilisation, redistribution and transformation of Fe minerals in the landscape (Johnston et al., 2011a) – …


Seawater Inundation Of Fe-Rich Coastal Lowlands – Hydrogeochemical Coupling And Hysteresis At The Tidal Fringe, Scott Johnston, Annabelle Keene, Richard Bush, Edward Burton, Leigh Sullivan Sep 2010

Seawater Inundation Of Fe-Rich Coastal Lowlands – Hydrogeochemical Coupling And Hysteresis At The Tidal Fringe, Scott Johnston, Annabelle Keene, Richard Bush, Edward Burton, Leigh Sullivan

Associate Professor Edward D Burton

Over 17 million ha of coastal lowlands contain acid sulfate soils (CASS). These soils are rich in meta-stable, redoxsensitive Fe (III)-minerals. Large areas of CASS are at risk of increased saline tidal inundation due to sea-level rise. Fieldbased CASS remediation trials reveal that tidal seawater inundation initiates radical changes in sediment hydrogeochemistry, stimulating Fe and SO4 reducing conditions, generating alkalinity and greatly decreasing the acidity hazard. However, these changes also have profound consequences for the fate, mobilisation, redistribution and transformation of Fe minerals and co-associated trace elements. Here, we examine the consequences for iron and arsenic by investigating the hydrology, …


Climate Change Impacts On Acid Sulfate Soil Landscapes, Richard Bush, Leigh Sullivan, Edward Burton, Scott Johnston, Annabelle Keene, Vanessa Wong, L Mosley Sep 2010

Climate Change Impacts On Acid Sulfate Soil Landscapes, Richard Bush, Leigh Sullivan, Edward Burton, Scott Johnston, Annabelle Keene, Vanessa Wong, L Mosley

Associate Professor Edward D Burton

The anticipated impacts of climate change are warmer conditions, an increasing proportion of rainfall to occur from heavy falls, increasing occurrence of drought in many regions, increasing frequency of intense tropical cyclones, rising sea levels and frequency of extreme high seas (e.g. storm surges). All of these predicted impacts have direct relevance to coastal acid sulfate soils landscapes, through either exacerbating sulfide oxidation by drought, re-instating reductive geochemical processes or changing the export and mobilisation of contaminants. The interaction of specific land management factors such as man-made drainage will also have a significant role in how the predicted impacts of …


Impacts Of Sea Level Rise On The Biogeochemistry Of A Coastal Floodplain In Eastern Australia, Vanessa Wong, Phillip Hirst, Scott Johnston, Richard Bush, Leigh Sullivan, Edward Burton, P Slavich Sep 2010

Impacts Of Sea Level Rise On The Biogeochemistry Of A Coastal Floodplain In Eastern Australia, Vanessa Wong, Phillip Hirst, Scott Johnston, Richard Bush, Leigh Sullivan, Edward Burton, P Slavich

Associate Professor Edward D Burton

No abstract provided.


Evaluation Of Existing Methods For Assessing Retained Acidity In Acid Sulfate Soil Materials, C Vithana, Leigh Sullivan, Richard Bush, Edward Burton, Scott Johnston Sep 2010

Evaluation Of Existing Methods For Assessing Retained Acidity In Acid Sulfate Soil Materials, C Vithana, Leigh Sullivan, Richard Bush, Edward Burton, Scott Johnston

Associate Professor Edward D Burton

No abstract provided.