[Bioavailability of As, Cu and Zn in two soils as affected by application of chicken manure and pig manure].
Animal manures contain higher As, Cu and Zn since organoarsenicals, copper and zinc additives are widely used in modern intensive animal production. A pot experiment in water spinach was conducted to investigate As, Cu and Zn bioavailability in a paddy soil (PS) and a lateritic red soil (LRS) applied with 2% and 4% (mass fraction) chicken manure (CM) and pig manure (PM), respectively. Soils without any fertilizer were included as the checks (CK). The results show that nearly all treatments with manures significantly increase the biomass of the above-ground part of water spinach compared to the CK. The biomass in PS is significantly greater than that in LRS. The As concentrations and uptake rates of water spinach are significantly enhanced by manure application, showing the rule of higher rates > lower rates, PM > CM and in PS> in LRS. Except for the Cu concentrations in PS, manure application significantly increases the Cu, Zn concentrations and uptake rates as well. Soil total As in all treatments slightly reduce, available As and percents of available As over total As (PAs) considerably decrease after the harvest of water spinach, but total Cu, Zn and available Cu, Zn and percents of available Cu and Zn over total Cu and Zn (PCu and PZn) nearly in all manure-amended treatments increase. Soil total As increases by 0.3-3.0 mg x kg(-1), available As by 0.011-0.034 mg x kg(-1), the PAs by 0.033-0.178 percentage points in all treatments with manures, as compared to the CK. Soil total Cu, available Cu and the PCu increases by 3.1-30.4 mg x kg(-1), 5.2-19.4 mg x kg(-1) and 1.2-34.1 percentage points, respectively. Those of Zn increase by--10.6-79.6 mg x kg(-1), 4.0-65.9 mg x kg(-1) and 1.0-64.2 percentage points. We assume that the bioavailability of soil heavy metals be evaluated by the increment of available concentration and percent available concentration over total concentration, higher rate manure application improves the bioavailability of soil As, Cu and Zn than lower rate one and in LRS than in PS.
Yao
Li-xian
LX
College of Environmental Science and Engineering, South China University of Technology, Guangzhou High Education Mega Center, Guangzhou 510006, China. lyaolx@yahoo.com.cn
Li
Guo-liang
GL
Dang
Zhi
Z
He
Zhao-huan
ZH
Zhou
Chang-min
CM
Yang
Bao-mei
BM
D000818:Animals; D001151:Arsenic / Q000032:analysis; D002645:Chickens; D003300:Copper / Q000032:analysis; D005308:Fertilizers; D027741:Ipomoea / Q000254:growth & development*; D008372:Manure; D019216:Metals, Heavy / Q000032:analysis*; D012989:Soil Pollutants / Q000032:analysis*; D013552:Swine; D015032:Zinc / Q000032:analysis
D005308:Fertilizers; D008372:Manure; D019216:Metals, Heavy; D012989:Soil Pollutants; D003300:Copper; D015032:Zinc; D001151:Arsenic