Modeling the toxicity of copper and zinc salts to wheat in 14 soils.
Interest is mounting in developing and utilizing soil-specific soil quality guidelines. This requires quantifying the effects that soil physicochemical properties have on various ecotoxicological endpoints, including phytotoxicity. To this end, 14 agricultural soils from Australia with differing soil properties were spiked with copper (Cu) and zinc (Zn) salts and used to conduct 21-d plant growth inhibition tests using wheat (Triticum aestivum L.) in pot trials. The toxicity of Cu and Zn was similar with 10% effect concentration (EC10) values ranging from 110 to 945 and from 235 to 965 mg/kg, respectively, while the corresponding median effect concentration (EC50) values ranged from 240 to 1,405 and 470 to 1,745 mg/kg, respectively. Copper toxicity values (EC10, EC20, and EC50) were best modeled by the logarithm of cation exchange capacity (CEC) and either soil pH or electrical conductivity. Zinc EC50 and EC20 values were best modeled using the logarithm of CEC, while the EC10 data were best modeled using soil pH and the logarithm of organic carbon. These models generally estimated toxicity within a factor of two of the measured values.
Warne
Michael St John
MS
Centre for Environmental Contaminants Research, Commonwealth Scientific and Industrial Research Organisation, Land and Water Division, Adelaide, South Australia 5064, Australia. michael.warne@csiro.au
Heemsbergen
Diane
D
Stevens
Darryl
D
McLaughlin
Mike
M
Cozens
Gillian
G
Whatmuff
Mark
M
Broos
Kris
K
Barry
Glenn
G
Bell
Mike
M
Nash
David
D
Pritchard
Deb
D
Penney
Nancy
N
D003300:Copper / Q000633:toxicity*; D006863:Hydrogen-Ion Concentration; D008962:Models, Theoretical; D012989:Soil Pollutants / Q000633:toxicity*; D014908:Triticum / Q000187:drug effects* / Q000254:growth & development; D015032:Zinc / Q000633:toxicity*
D012989:Soil Pollutants; D003300:Copper; D015032:Zinc