Submitted to: American Society of Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 4/28/2004
Publication Date: 10/31/2004
Citation: Kukier, U., Chaney, R.L., Ryan, J.A., Dowdy, R.H., Daniels, W.L., Granato, T. 2004. Phytoavailability of Cd to wheat from long-term biosolids and Cd-salt amended soils [abstract]. American Society of Agronomy Abstracts. Paper No. 3462. Interpretive Summary: Summary.
Technical Abstract: Our previous study with lettuce indicated that the phytoavailability of added salt-Cd is lower in long-term biosolids-amended soils than in non-amended soils. Reduced Cd phytoavailability in biosolids-amended soils is attributed to the increase in soil sorptive capacity. To further test the hypothesis that biosolids amended soils reduce Cd phytoavailability, durum wheat (Triticum turgidum L. subsp. durum) was grown in soils previously cropped to lettuce. Five rates of Cd (as nitrate, from 0 to 10 mg kg-1 were mixed with soils from paired long term biosolids-amended and control plots. The pH of all soils measured in 0.01 M calcium nitrate was adjusted to 6.5. Durum wheat was grown as a second crop, following lettuce. Wheat shoot Cd increased linearly with Cd-salt rate (R2 greater than 0.95). In most cases, salt-Cd was much less available to wheat in biosolids-amended soils than in control soils. For example, Cd uptake slope for control Christiana MD soil was 3.85, and 0.88 for soil amended with 668 Mg ha-1 composted biosolids. Cd-uptake slopes were inversely related to soil organic-C, oxalate extractable Al and Fe and other soil properties. Cd uptake by wheat will be evaluated in relation to biosolids properties, soil-Cd extractability and desorption characteristics. Similarities and differences between the response of wheat and lettuce to Cd-salt addition will be discussed.