Testing aluminum addition as a tool for lake restoration in shallow, eutrophic Lake Sønderby, Denmark

Variations in the aluminum:phosphorus binding ratio and alum dosage considerations for Half Moon Lake, Wisconsin

“…In those cases where labile organic P concentrations are high, Reitzel et al (2003Reitzel et al ( , 2005 and de Vicente et al (2008a) discussed methodology and approaches for incorporating this source into Al dosage calculations. Assuming that the entire labile organic P pool will be converted to PO −3 4 in time, its concentration could be added to the redox-P concentration to calculate Al dosage (Reitzel et al 2003).…”

“…Various studies on Al dosage requirements to inactivate sediment P have reported Al:P binding ratios ranging from 2:1 to >100:1 (Rydin and Welch 1999, Rydin et al 2000, Lewandowski et al 2003, Reitzel et al 2003, 2005, James 2005, Dugopolski et al 2008. Under controlled experimental conditions with analytical grade phosphate (PO −3 4 ) and alum, P can bind to precipitated Al(OH) 3 at a molar ratio of ∼1:1 or slightly higher at neutral pH, depending on the initial PO −3 4 concentration and the extent of polymer formation (Lijklema 1980).…”

Diagenesis of settling seston: identity and transformations of organic phosphorus

“…Analysis of sediment cores has been used to demonstrate changes in P pools over decadal periods [1][2][3] and to predict P release under changing environmental conditions. 4,5 However, few studies have investigated the impact of settling seston on P cycling in the water column or on sediment P composition. Pettersson 6 followed P transformations in settling seston using sequential fractionation and showed a gradual decrease in total P (TP) from suspended matter to settling particles and surface sediment, while more recent studies demonstrated that settling seston can contribute significantly to P accumulation in the hypolimnion of stratified deep lakes.…”

Alum:Redox-Sensitive Phosphorus Ratio Considerations and Uncertainties in the Estimation of Alum Dosage to Control Sediment Phosphorus

“…Laboratory assay techniques (Rydin and Welch 1999 and results reported herein) indicate a ratio on the order of 100:1 is needed to bind redox-sensitive sediment P. However, Rydin et al (2000) found much lower ratios of ~11:1 in sediment profiles of alum treated lakes that exhibited long term water quality improvement after treatment. Reitzel et al (2003) suggested that a molar ratio of 4:1 was sufficient to immobilize sediment P in Lake Sonderby, Denmark. Field case studies of lake sediments treated with high doses of alum are needed in order to corroborate laboratory assay findings and to more accurately evaluate optimal (and cost effective) Al:P binding ratios for use in redox-sensitive sediment P-based dosage calculations.…”