The potential of selected macroalgal species for treatment of AMD at different pH ranges in temperate regions.
The metal bioaccumulation potential of selected macroalgae species at different pH ranges was study for usage as part of a possible secondary passive acid mine drainage (AMD) treatment technology in algae ponds. Two separate studies were conducted to determine the suitability of macroalgae for passive treatment when metabolic processes in macrophytes and microorganisms in constructed wetlands decrease during winter months. In the field study, the bioconcentration of metals (mg/kg dry weight) measured in the benthic macroalgae mats was in the following order: site 1. Oedogonium crassum Al > Fe > Mn > Zn; site 2. Klebsormidium klebsii, Al > Fe > Mn > Zn; site 3. Microspora tumidula, Fe > Al > Mn > Zn and site 4. M. tumidula, Fe > Mn > Al > Zn. In the laboratory study, cultured macroalgae K. klebsii, O. crassum and M. tumidula isolated from the field sampling sites were exposed to three different pH values (3, 5 and 7), while bioaccumulation of the metals, Al, Fe, Mn and Zn and glutathione S-transferase (GST) activity were measured in the different selected algae species at a constant water temperature of 14 °C. Bioaccumulation of Al was the highest for O. crassum followed by K. klebsii and M. tumidula (p < 0.0001). From the study it was evident that the highest metal bioaccumulation occurred in the macroalgae O. crassum at all three tested pH values under constant low water temperature.
CSIR Natural Resources and the Environment, P.O. Box 320, Stellenbosch, 7599, South Africa; Department of Paraclinical Sciences, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, 0110, South Africa.
Paul J
PJ
Oberholster
CSIR Natural Resources and the Environment, P.O. Box 320, Stellenbosch, 7599, South Africa; Department of Genetics, University of Stellenbosch, Private Bag X1, Matieland, Stellenbosch, 7601, South Africa.
Po-Hsun
PH
Cheng
Department of Genetics, University of Stellenbosch, Private Bag X1, Matieland, Stellenbosch, 7601, South Africa. Electronic address: ambo@sun.ac.za.
Anna-Maria
AM
Botha
CSIR Natural Resources and the Environment, P.O. Box 320, Stellenbosch, 7599, South Africa.
Bettina
B
Genthe
D000460:Chlorophyta / Q000378:metabolism*; D003080:Cold Temperature; D005982:Glutathione Transferase / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000378:metabolism*; D008906:Mining / Q000379:methods*; D013019:South Africa; D013045:Species Specificity; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification / Q000379:methods*
D008670:Metals; D014874:Water Pollutants, Chemical; D005982:Glutathione Transferase
AMD; Acidophilic filamentous macroalgae; Bioaccumulation; Oxidative stress