Monitoring and assessment of surface water acidification following rewetting of oxidised acid sulfate soils

  title={Monitoring and assessment of surface water acidification following rewetting of oxidised acid sulfate soils},
  author={Luke M. Mosley and Benjamin Zammit and A. M. Jolley and Liz Barnett and Rob W. Fitzpatrick},
  journal={Environmental Monitoring and Assessment},
Large-scale exposure of acid sulfate soils during a hydrological drought in the Lower Lakes of South Australia resulted in acidification of surface water in several locations. Our aim was to describe the techniques used to monitor, assess and manage these acidification events using a field and laboratory dataset (n = 1,208) of acidic to circum-neutral pH water samples. The median pH of the acidified (pH < 6.5) samples was 3.8. Significant (p < 0.05) increases in soluble metals (Al, Co, Mn, Ni… Expand
Porewater geochemistry of inland Acid sulfate soils with sulfuric horizons following postdrought reflooding with freshwater.
It is proposed that low pH conditions inhibited the activity of SO-reducing bacteria and, in turn, the in situ generation of alkalinity through pyrite production, leading to in situ changes to soil acidity and abundance of metals and metalloids. Expand
Acidification of floodplains due to river level decline during drought.
Results from 2-dimensional modelling of the river-floodplain hydrological processes were consistent with field measurements during the drying phase and illustrated how the declining river levels led to floodplain acidification. Expand
Metal speciation and potential bioavailability changes during discharge and neutralisation of acidic drainage water.
For dilutions of the drainage waters of less than 1% with Murray River water, none of the metals should exceed the WQGs, however, the high concentrations of metals associated with fine precipitates within the receiving waters may represent a risk to some aquatic organisms. Expand
Predictive modelling of pH and dissolved metal concentrations and speciation following mixing of acid drainage with river water
Abstract Discharge of acidic drainage from mining operations or acid sulphate soils can create severe environmental impacts if not managed appropriately. We tested different hydro-geochemical modelsExpand
Net acidity indicates the whole effluent toxicity of pH and dissolved metals in metalliferous saline waters.
Results indicate that rapid in-field assessments of net acidity in acidic, Al dominated waters may be an indicator of potential acute and sub-chronic impacts on aquatic organisms. Expand
Effect of cyclic redox oscillations on water quality in freshwater acid sulfate soil wetlands.
It is suggested that retaining surface water in ASS wetlands for ~8weeks after a dry-wet transition will allow sufficient time for alkalinity producing reductive processes to ameliorate most surface water acidity. Expand
Extreme drought causes distinct water acidification and eutrophication in the Lower Lakes (Lakes Alexandrina and Albert), Australia
Abstract Droughts are set to increase in frequency and magnitude with climate change and water extraction, and understanding their influence on ecosystems is urgent in the Holocene. Low rainfallExpand
Air-water CO2 outgassing in the Lower Lakes (Alexandrina and Albert, Australia) following a millennium drought.
This study presents spatiotemporal changes of dissolved inorganic carbon and water - to- air interface CO2 flux in the two of Australia's largest connected, yet geomorphically different freshwater lakes (Lake Alexandrina and Lake Albert, South Australia), during drought and post-drought. Expand
Geochemical processes following freshwater reflooding of acidified inland acid sulfate soils: An in situ mesocosm experiment
Abstract In their oxidised form, inland acid sulfate soils (IASS) with sulfuric horizons (pH ≤ 3.5) contain substantial acidity and pose a number of threats to surrounding ecosystems. In theirExpand
Extreme drought decouples silicon and carbon geochemical linkages in lakes.
The backward stepwise regression analysis that could avoid multicollinearity suggested that DSi:HCO3- ratio in drought period had significant relationships with fewer variables when compared to the post-drought, and was better predictable using nutrient variables during post-Drought. Expand


Climate-driven mobilisation of acid and metals from acid sulfate soils
The recent drought in south-eastern Australia has exposed to air, large areas of acid sulfate soils within the River Murray system. Oxidation of these soils has the potential to release acidity,Expand
Sedimentary iron geochemistry in acidic waterways associated with coastal lowland acid sulfate soils
Abstract We examined the solubility, mineralogy and geochemical transformations of sedimentary Fe in waterways associated with coastal lowland acid sulfate soils (CLASS). The waterways containedExpand
Export of Acidity in Drainage Water from Acid Sulphate Soils
Disturbed acid sulphate soils are potent sources of acidity in coastal waterways. Monitoring studies of the drainage water for sites at East Trinity, Cairns and Pimpama, south-east QueenslandExpand
A sulfur-stable-isotope-based screening tool for assessing impact of acid sulfate soils on waterways
Early warning indicators for waterways affected by acid sulfate soils (ASS) are valuable tools for water management organisations. Oxidised ASS may discharge high concentrations of metals, acid andExpand
Metal species in a Boreal river system affected by acid sulfate soils
Abstract The bioavailability of metals and their potential for environmental pollution depends not simply on total concentrations but on their chemical form. Consequently, knowledge of aqueous metalExpand
Discharge of weathering products from acid sulfate soils after a rainfall event, Tweed River, eastern Australia
Abstract The oxidation of the iron sulfide, pyrite, in acid sulfate soil floodplains generate substantial acidity and this acid has caused further weathering of the soil profile. The movement ofExpand
Buffering of Acidic Mine Lakes: The Relevance of Surface Exchange and Solid- Bound Sulphate
Abstract.Buffering mechanisms in an acidic mine lake in Lusatia, Germany were investigated. The titration curve has four sections with different buffering mechanisms: (1) buffering by free hydrogenExpand
Iron precipitate accumulations associated with waterways in drained coastal acid sulfate landscapes of eastern Australia
Iron precipitate accumulations from surface environments surrounding waterways (such as the side of drains and soil surface horizons) in acid sulfate soil landscapes were analysed for theirExpand
Mobility of arsenic and selected metals during re-flooding of iron- and organic-rich acid-sulfate soil
Abstract The drainage-induced oxidation of iron-sulfide minerals in acid-sulfate soils has adversely affected large areas of coastal floodplains. Re-flooding of these soils, via the re-establishmentExpand
Net alkalinity and net acidity 2: Practical considerations
The pH, alkalinity, and acidity of mine drainage and associated waters can be misinterpreted because of the chemical instability of samples and possible misunderstandings of standard analyticalExpand