Hydrochemistry of episodic drainage waters discharged from an acid sulfate soil affected catchment

Acid rock drainage and climate change

“…Increases in acidity and metals during early stages of rising discharge, or first flush, in areas of acid sulfate soils has been noted by Green et al (2006). They state that this increase in solute concentrations is caused by dissolution of soluble salts in the drainage area.…”

Schwertmannite stability in acidified coastal environments

“…This is largely due to the extremely low solubility of the thermodynamically stable Fe(III) oxidation state at circumneutral pH in well-oxygenated soils and surface waters. However, in many coastal floodplains formed during the Holocene period, massive quantities of Fe (and Al) are periodically discharged from disturbed acid sulfate soils to surrounding estuarine and coastal environments (Green et al, 2006a(Green et al, , 2006bMacdonald et al, 2007). The large-scale deoxygenation and acidification of these aquatic environments, caused in part by the oxidation of Fe(II) and subsequent hydrolysis of Fe(III), often results in the mass mortality of gilled organisms and is of particular concern in the tropical and sub-tropical regions of south east Asia and north east Australia (Dent and Pons, 1995;White et al, 1997).…”

Effectiveness of an Open Limestone Channel in Treating Acid Sulfate Soil Drainage

“…During large rainfall events acidity and metal weathering products that are flushed from the soil profile into the discharge waters are diluted by rainfall. The OLC is design to treat the first flush and recession water discharges which contain significant quantities of acidity and mineral weathering products and are most problematic (Green et al 2006).…”