title: Enhancement of Cd phytoextraction by hyperaccumulator Sedum alfredii using electrical field and organic amendments.
abstract: The combined use of organic amendment-assisted phytoextraction and electrokinetic remediation to decontaminate Cd-polluted soil was demonstrated in a laboratory-scale experiment. The plant species selected was the hyperaccumulator Sedum alfredii. Prior to the pot experiment, the loamy soil was treated with 15 g kg-1of pig manure compost, 10 g kg-1of humic acid, or 5 mmol kg-1of EDTA, and untreated soil without application of any amendment was the control. Two conditions were applied to each treatment: no voltage (without an electrical field) and a direct current (DC) electrical field (1 V cm-1with switching polarity every day). Results indicated that Cd concentrations in S. alfredii were significantly (p < 0.05) increased by application of the electrical field and soil amendments (pig manure compost, humic acid, and EDTA). By switching the polarity of the DC electrical field, significant pH variation from anode to cathode can be avoided, and no significant impact was observed on shoot biomass production. Electrical field application increased DTPA-extractable Cd in soils and the Cd accumulation in shoots by 6.06-15.64 and 24.53-52.31%, respectively. The addition of pig manure compost and humic acid enhanced shoot Cd accumulation by 1.54- to 1.92- and 1.38- to 1.64-fold because of their simultaneous enhancement of Cd concentration in shoots and biomass production. However, no enhancement of Cd accumulation was found in the EDTA treatment, which can be ascribed to the inhibition of plant growth caused by EDTA. In conclusion, pig manure compost or humic acid addition in combination with the application of a switched-polarity DC electrical field could significantly enhance Cd phytoextraction by hyperaccumulator S. alfredii.
authors.affiliation: State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China.
authors.forename: Wendan
authors.initials: W
authors.lastname: Xiao
authors.affiliation: Hangzhou Plant Protection and Soil Fertilizer Station, Hangzhou, 310020, China.
authors.forename: Dan
authors.initials: D
authors.lastname: Li
authors.affiliation: State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China. xuezhuye@aliyun.com.
authors.forename: Xuezhu
authors.identifier: http://orcid.org/0000-0002-6557-6209
authors.initials: X
authors.lastname: Ye
authors.affiliation: College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, 311300, China.
authors.forename: Haizhou
authors.initials: H
authors.lastname: Xu
authors.affiliation: College of Environmental and Resource Sciences, Zhejiang A&F University, Hangzhou, 311300, China.
authors.forename: Guihua
authors.initials: G
authors.lastname: Yao
authors.affiliation: Hangzhou Plant Protection and Soil Fertilizer Station, Hangzhou, 310020, China.
authors.forename: Jingwen
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Hu
authors.affiliation: State Key Laboratory Breeding Base for Zhejiang Sustainable Pest and Disease Control, Institute of Quality and Standard for Agro-products, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China.
authors.forename: Na
authors.initials: N
authors.lastname: Gao
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D018533:Biomass; D002104:Cadmium; D004560:Electricity; D008372:Manure; D031963:Sedum; D012987:Soil; D012989:Soil Pollutants; D013552:Swine
chemical_list: D008372:Manure; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium
keywords: Cadmium; Electrokinetic remediation; Organic amendment; Phytoextraction; Sedum alfredii