Bio-organic stabilizing agent shows promising prospect for the stabilization of cadmium in contaminated farmland soil
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In situ immobilization of cadmium (Cd) has been considered as a cost-effective and non-disruptive remediation technique for Cd-contaminated soils. In this study, several immobilization approaches were compared in a Cd-contaminated agricultural farmland. The soil was treated with different combinations of the immobilizing agents such as biochar (C), rice straw (RS), lime (L), and engineered bacteria P. putida X4/pIME (B). The plant yield and Cd uptake of lettuce as well as soil Cd fractionations were measured. The Cd content in lettuce leaves and roots decreased by 46.8~67.2% and 36.8~60.2%, respectively. Among the five treatments, combined rice straw, lime, and engineered bacteria treatment showed the lowest Cd concentration in lettuce leaves (0.14 mg/kg) and the highest plant yield (21.5 t/ha). The alleviating effects are assigned to the significant transformation of water soluble and exchangeable Cd to humic substance bound, strong organic bound and residual Cd in the soils. This study suggests that this bio-organic stabilizing agent is more cost-effective than some other immobilization agents reported previously, and shows a great application prospect in improving agriculture production of heavy metal-polluted agricultural soils.
KeywordsIn situ immobilization Cd Rice straw Biochar Lime Bacteria P. putida X4/pIME Cost-effective
This work was supported by the National Key Research and Development Program (2017YFA0605001) and Major Technological Innovation Projects of Hubei Province (2018ABA092).
- Bao SD (2000) Soil and agricultural chemistry analysis. Agriculture Publication, Beijing (in Chinese)Google Scholar
- Bian RJ, Joseph S, Cui LQ, Pan GX, Li LQ, Liu XY, Zhang AF, Rutlidge H, Wong SW, Chia C, Marjo C, Gong B, Munroe P, Marjo C (2014) A three-year experiment confirms continuous immobilization of cadmium and lead in contaminated paddy field with biochar amendment. J Hazard Mater 272:121–128CrossRefGoogle Scholar
- MEP and Ministry of Land and Resources (MLR) (2014) MEP and MLR announce the report on national general survey on soil contamination. http://english.mep.gov.cn/News_service/news_release/201404/t20140428_271088.htm. Accessed 28 Apr 2014