Development and validation of a terrestrial biotic ligand model predicting the effect of cobalt on root growth of barley (Hordeum vulgare).
A Biotic Ligand Model was developed predicting the effect of cobalt on root growth of barley (Hordeum vulgare) in nutrient solutions. The extent to which Ca(2+), Mg(2+), Na(+), K(+) ions and pH independently affect cobalt toxicity to barley was studied. With increasing activities of Mg(2+), and to a lesser extent also K(+), the 4-d EC50(Co2+) increased linearly, while Ca(2+), Na(+) and H(+) activities did not affect Co(2+) toxicity. Stability constants for the binding of Co(2+), Mg(2+) and K(+) to the biotic ligand were obtained: logK(CoBL)=5.14, logK(MgBL)=3.86 and logK(KBL)=2.50. Limited validation of the model with one standard artificial soil and one standard field soil showed that the 4-d EC50(Co2+) could only be predicted within a factor of four from the observed values, indicating further refinement of the BLM is needed.
Lock
K
K
Ghent University, Laboratory of Environmental Toxicology and Aquatic Ecology, J Plateaustraat 22, Ghent, Belgium. koen_lock@hotmail.com
De Schamphelaere
K A C
KA
Becaus
S
S
Criel
P
P
Van Eeckhout
H
H
Janssen
C R
CR
D001682:Biological Availability; D002118:Calcium / Q000378:metabolism; D003035:Cobalt / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*; D017753:Ecosystem; D004781:Environmental Exposure / Q000009:adverse effects; D001467:Hordeum / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D006859:Hydrogen / Q000378:metabolism; D007477:Ions / Q000378:metabolism; D008024:Ligands; D008274:Magnesium / Q000378:metabolism; D008954:Models, Biological; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D018570:Risk Assessment / Q000379:methods; D012964:Sodium / Q000378:metabolism; D012987:Soil / Q000032:analysis; D012989:Soil Pollutants / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity*
D007477:Ions; D008024:Ligands; D012987:Soil; D012989:Soil Pollutants; D003035:Cobalt; D006859:Hydrogen; D012964:Sodium; D008274:Magnesium; D011188:Potassium; D002118:Calcium