title: Accumulation of Cr, Cd, Pb, Cu, and Zn by plants in tanning sludge storage sites: opportunities for contamination bioindication and phytoremediation.
abstract: Tanning sludge enriched with high concentrations of Cr and other metals has adverse effects on the environment. Plants growing in the metalliferous soils may have the ability to cope with high metal concentrations. This study focuses on potentials of using native plants for bioindication and/or phytoremediation of Cr-contaminated sites. In the study, we characterized plants and soils from six tanning sludge storage sites. Soil in these sites exhibited toxic levels of Cr (averaged 16,492 mg kg-1) and other metals (e.g., 48.3 mg Cu kg-1, 2370 mg Zn kg-1, 44.9 mg Pb kg-1, and 0.59 mg Cd kg-1). Different metal tolerance and accumulation patterns were observed among the sampled plant species. Phragmites australis, Zephyranthes candida, Cynodon dactylon, and Alternanthera philoxeroides accumulated moderate-high concentrations of Cr and other metals, which could make them good bioindicators of heavy metal pollution. High Cr and other metal concentrations (e.g., Cd and Pb) were found in Chenopodium rubrum (372 mg Cr kg-1), Aster subulatus (310 mg Cr kg-1), and Brassica chinensis (300 mg Cr kg-1), being considered as metal accumulators. In addition, Nerium indicum and Z. candida were able to tolerate high concentrations of Cr and other metals, and they may be used as preferable pioneer species to grow or use for restoration in Cr-contaminated sites. This study can be useful for establishing guidelines to select the most suitable plant species to revegetate and remediate metals in tanning sludge-contaminated fields.
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 301021, China. huayang1202@sohu.com.
authors.forename: Yongqiang
authors.initials: Y
authors.lastname: Yuan
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen, 301021, China.
authors.forename: Shen
authors.initials: S
authors.lastname: Yu
authors.affiliation: Water Management Research Unit, United States Department of Agriculture, Agricultural Research Service, San Joaquin Valley Agricultural Sciences Center, 9611 South Riverbend Avenue, Parlier, CA, 93648-9757, USA.
authors.forename: G S
authors.initials: GS
authors.lastname: Bañuelos
authors.affiliation: College of Environmental & Resource Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, 310058, China.
authors.forename: Yunfeng
authors.initials: Y
authors.lastname: He
mesh_terms: D001673:Biodegradation, Environmental; D002104:Cadmium / Q000737:chemistry; D002857:Chromium / Q000737:chemistry; D003300:Copper / Q000737:chemistry; D007854:Lead / Q000737:chemistry; D019216:Metals, Heavy / Q000737:chemistry* / Q000378:metabolism; D010944:Plants / Q000378:metabolism*; D012722:Sewage / Q000737:chemistry*; D012987:Soil; D013633:Tanning; D014874:Water Pollutants, Chemical / Q000737:chemistry; D015032:Zinc / Q000737:chemistry
chemical_list: D019216:Metals, Heavy; D012722:Sewage; D012987:Soil; D014874:Water Pollutants, Chemical; D002104:Cadmium; D002857:Chromium; D007854:Lead; D003300:Copper; D015032:Zinc
keywords: Bioindicator; Cr contamination; Phytoaccumulation; Tanning sludge storage site; Tolerant plants