http://researchonline.federation.edu.au/vital/access/manager/Index ${session.getAttribute("locale")} 5 Spatial and temporal changes in estuarine water quality during a post-flood hypoxic event http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10424 Wed 07 Apr 2021 13:55:47 AEST ]]> Seawater inundation of coastal floodplain sediments : Short-term changes in surface water and sediment geochemistry http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10423 Wed 07 Apr 2021 13:55:47 AEST ]]> Seawater-induced mobilization of trace metals from mackinawite-rich estuarine sediments http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10422 Wed 07 Apr 2021 13:55:47 AEST ]]> Anthropogenic forcing of estuarine hypoxic events in sub-tropical catchments : Landscape drivers and biogeochemical processes http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10421 Wed 07 Apr 2021 13:55:47 AEST ]]> Seawater causes rapid trace metal mobilisation in coastal lowland acid sulfate soils : Implications of sea level rise for water quality http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10420 Wed 07 Apr 2021 13:55:47 AEST ]]> Effects of hyper-enriched reactive Fe on sulfidisation in a tidally inundated acid sulfate soil wetland http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10400 Wed 07 Apr 2021 13:55:45 AEST ]]> Enrichment and heterogeneity of trace elements at the redox-interface of Fe-rich intertidal sediments http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10399 Wed 07 Apr 2021 13:55:45 AEST ]]> Reactive trace element enrichment in a highly modified, tidally inundated acid sulfate soil wetland : East Trinity, Australia http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10398 Wed 07 Apr 2021 13:55:45 AEST ]]> Tidally driven water column hydro-geochemistry in a remediating acidic wetland http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10397 Wed 07 Apr 2021 13:55:45 AEST ]]> Contemporary pedogenesis of severely degraded tropical acid sulfate soils after introduction of regular tidal inundation http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10396 1 m) in the underlying sulfidic horizons. δ34S data indicate that tidal inundation caused exchange of marine solutes within former sulfuric horizons, but not within underlying sulfidic material. There was considerable reformation of pyrite within former sulfuric horizons after tidal inundation with reduced inorganic sulfur increasing by ∼ 60 μmol g- 1. Acid-volatile sulfide also accumulated, but mainly near the soil surface (up to 16 μmol g- 1). Reduction of Fe(III) minerals strongly influences the geochemistry of the tidally inundated soils. After tidal inundation the soil pH and Eh closely followed the iron redox couple and there was non-sulfidic solid-phase Fe(II) up to 600 μmol g- 1. There was also substantial diagenetic enrichment of poorly crystalline Fe-oxides near the soil surface following tidal inundation, with reactive Fe spanning 400-1800 μmol g- 1. While the decreases in soil acidity documented here are likely due to a combination of marine alkalinity inputs and reduction of both Fe and SO42-, the relative importance of each process remains to be determined. This study demonstrates that marine tidal inundation can be an effective landscape-scale strategy for ameliorating severe acidity associated with drained acid sulfate soils. © 2008 Elsevier B.V. All rights reserved.]]> Wed 07 Apr 2021 13:55:45 AEST ]]> Iron geochemical zonation in a tidally inundated acid sulfate soil wetland http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10395 30mmol L-1) in former sulfuric horizons in the upper-intertidal zone. Tidal forcing generated oscillating hydraulic gradients, driving upward advection of this Fe2+-enriched porewater along the intertidal slope. Subsequent oxidation of Fe2+ led to substantial accumulation of reactive Fe(III) fractions (up to 8000μmol g-1) in redox-interfacial, tidal zone sediments. These Fe(III)-precipitates were poorly crystalline and displayed a distinct mineralisation sequence related to tidal zonation. Schwertmannite (Fe8O8(OH)6SO4) was the dominant Fe mineral phase in the upper-intertidal zone at mainly low pH (3-4). This was followed by increasing lepidocrocite (γ-FeOOH) and goethite (α-FeOOH) at circumneutral pH within lower-intertidal and subtidal zones. Relationships were evident between Fe fractions and topography. There was increasing precipitation of Fe-sulfide minerals and non-sulfidic solid-phase Fe(II) in the lower intertidal and subtidal zones. Precipitation of Fe-sulfide minerals was spatially co-incident with decreases in porewater Fe2+. A conceptual model is presented to explain the observed landscape-scale patterns of Fe mineralisation and hydro-geochemical zonation. This study provides valuable insights into the hydro-geochemical processes caused by saline tidal inundation of low lying CASS landscapes, regardless of whether inundation is an intentional strategy or due to sea-level rise. © 2010 Elsevier B.V.]]> Wed 07 Apr 2021 13:55:45 AEST ]]> Arsenic mobilization in a seawater inundated acid sulfate soil http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10394 Wed 07 Apr 2021 13:55:45 AEST ]]> Quantifying alkalinity generating processes in a tidally remediating acidic wetland http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10393 tidal exchange (25-42%)>sulfate reduction (7-13%)>>hydrated lime addition (<1%). Accurately attributing the relative contributions due to Fe and SO 4 2- reduction was limited by an inability to distinguish between non-sulfidic, solid-phase Fe(II) generated by microbial dissimilatory reduction of Fe(III) or chemical reduction of Fe(III) by H 2S. Nevertheless, the combined alkalinity contribution of these two electron accepting processes accounts for between 58 and 74% of the total. The majority (>99%) of net alkalinity generation was due to either tides or microbial metabolism. This indicates that the LATE remediation technique is both a cost effective means of decreasing soil acidity and is readily transferable to similar CASS landscapes - provided there is adequate supply of suitable electron donors and sufficient regenerative capacity in the adjacent estuarine/marine tidal HCO 3 - pool. © 2012 Elsevier B.V.]]> Wed 07 Apr 2021 13:55:45 AEST ]]> Iron and arsenic cycling in intertidal surface sediments during wetland remediation http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10392 95% of the As(aq) within the first 4 h of aeration. Ferrihydrite transformed to schwertmannite within 23 days, although sorbed/coprecipitated As(III) remained unoxidized during this period. Schwertmannite subsequently transformed to jarosite at low pH (2-3), accompanied by oxidation of remaining Fe 2+. This coincided with a repartitioning of some sorbed As back into the aqueous phase as well as oxidation of sorbed/coprecipitated As(III) to As(V). Fe(III) precipitates formed via groundwater aeration were highly prone to reductive dissolution, thereby posing a high risk of mobilizing sorbed/coprecipitated As during any future upward migration of redox boundaries. Longer-term investigations are warranted to examine the potential pathways and magnitude of arsenic mobilization into surface waters in tidally reflooded wetlands. © 2011 American Chemical Society.]]> Wed 07 Apr 2021 13:55:45 AEST ]]> Changes in water quality following tidal inundation of coastal lowland acid sulfate soil landscapes http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10391 Wed 07 Apr 2021 13:55:45 AEST ]]> Pore water sampling in acid sulfate soils : A new peeper method http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10390 1 m deep in acid sulfate soil or any other firm wetland soils. Copyright © 2009 by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America. All rights reserved.]]> Wed 07 Apr 2021 13:55:45 AEST ]]> Arsenic mobilization during seawater inundation of acid sulfate soils - Hydrogeochemical coupling at the tidal fringe http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10389 Wed 07 Apr 2021 13:55:45 AEST ]]> Abundance and fractionation of Al, Fe and trace metals following tidal inundation of a tropical acid sulfate soil http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10388 Wed 07 Apr 2021 13:55:45 AEST ]]> Iron(III) accumulations in inland saline waterways, Hunter Valley, Australia : Mineralogy, micromorphology and pore-water geochemistry http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10387 Wed 07 Apr 2021 13:55:44 AEST ]]> Partitioning of metals in a degraded acid sulfate soil landscape : Influence of tidal re-inundation http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10385 Wed 07 Apr 2021 13:55:44 AEST ]]> A simple and inexpensive chromium-reducible sulfur method for acid-sulfate soils http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10378 Wed 07 Apr 2021 13:55:44 AEST ]]> Arsenic effects and behavior in association with the fe(II)-catalyzed transformation of schwertmannite http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10377 Wed 07 Apr 2021 13:55:44 AEST ]]> Mobility of arsenic and selected metals during re-flooding of iron- and organic-rich acid-sulfate soil http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10375 Wed 07 Apr 2021 13:55:44 AEST ]]> Iron-monosulfide oxidation in natural sediments : Resolving microbially mediated S transformations using XANES, electron microscopy, and selective extractions http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10374 Wed 07 Apr 2021 13:55:44 AEST ]]> Sorption of Arsenic(V) and Arsenic(III) to schwertmannite http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10373 4.6). Sorption of As(V) and As(III) caused significant release of SO 4 2- from within the schwertmannite solid-phase, without major degradation of the schwertmannite structure (as evident by X-ray diffraction and Raman spectroscopy). This can be interpreted as arsenic sorption via incorporation into the schwertmannite structure, rather than merely surface complexation at the mineral-water interface. The results of this study have important implications for arsenic mobility in the presence of schwertmannite, such as in areas affected by acidmine drainage and acid-sulfate soils. In particular, arsenic speciation, arsenic loading, and pH should be considered when predicting and managing arsenic mobility in schwertmanniterich systems. © 2009 American Chemical Society.]]> Wed 07 Apr 2021 13:55:44 AEST ]]> Sulfur biogeochemical cycling and novel Fe-S mineralization pathways in a tidally re-flooded wetland http://researchonline.federation.edu.au/vital/access/manager/Repository/vital:10372 Wed 07 Apr 2021 13:55:43 AEST ]]>