[Evaluation of phytoavailability of zinc and cadmium in contaminated soils by a short sequential extraction procedure].
Cultivated soils and maize samples from heavy metal contaminated locations affected by zinc smelting activities were collected in Hezhang County, Guizhou Province. Chemical fractions of zinc and cadmium (extracted by 0.01 mol x L(-1) CaCl2 and 0.005 mol x L(-1) DTPA) were evaluated by using a short three-step sequential extraction procedure. Results showed that Zn and Cd in soil were dominated by residual fraction, while the CaCl2 extractable and DTPA extractable fraction are only accounted for 0.63%, 3.91% for Zn, and 10.94%, 10.13% for Cd, respectively. Correlation analyses demonstrated that soil CaCl2 extractable metals were not correlated with maize metal concentrations, whereas the DTPA extractable fraction, residual fraction and total Zn and Cd concentrations were correlated significantly with the metal concentrations in maize roots, stems and leaves. These results indicated that CaCl2 extractable fraction may not pay important role on metal phytoavailability in the studied soils. While DTPA extractable fraction and total metal concentrations can be employed to evaluate metals phytoavailability.
Bi
Xiang-yang
XY
State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China.
Yang
Yuan-gen
YG
Feng
Xin-bin
XB
Li
Fei-li
FL
Sun
Li
L
D001673:Biodegradation, Environmental; D002104:Cadmium / Q000032:analysis / Q000302:isolation & purification*; D004784:Environmental Monitoring; D012989:Soil Pollutants / Q000032:analysis / Q000302:isolation & purification*; D003313:Zea mays / Q000737:chemistry / Q000378:metabolism*; D015032:Zinc / Q000032:analysis / Q000302:isolation & purification*
D012989:Soil Pollutants; D002104:Cadmium; D015032:Zinc