title: Effects of root exudates on the leachability, distribution, and bioavailability of phenanthrene and pyrene from mangrove sediments.
abstract: In this study, column leaching experiments were used to evaluate the leachability, distribution and bioavailability of phenanthrene and pyrene by root exudates from contaminated mangrove sediments. We observed that root exudates significantly promoted the release and enhanced the bioavailability of phenanthrene and pyrene from sediment columns. The concentration of phenanthrene and pyrene and cumulative content released from the analyzed sediment samples following root exudate rinsing decreased in the following order: citric acid > oxalic acid > malic acid. After elution, the total concentrations of phenanthrene and pyrene in sediment layers followed a descending order of bottom (9-12 cm) > middle (5-7 cm) > top (0-3 cm). Furthermore, a positive correlation between leachate pH values and PAH concentrations of the leachate was found. Consequently, the addition of root exudates can increase the leachability and bioavailability of phenanthrene and pyrene.
authors.affiliation: Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen, 361102, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Jia
authors.affiliation: Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen, 361102, China.
authors.forename: Haoliang
authors.initials: H
authors.lastname: Lu
authors.affiliation: Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen, 361102, China.
authors.forename: Jingchun
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen, 361102, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Li
authors.affiliation: Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen, 361102, China.
authors.forename: Minyue
authors.initials: M
authors.lastname: Dai
authors.affiliation: Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen, 361102, China. ycl@xmu.edu.cn.
authors.forename: Chongling
authors.initials: C
authors.lastname: Yan
mesh_terms: D001673:Biodegradation, Environmental; D002681:China; D005240:Feasibility Studies; D019015:Geologic Sediments / Q000737:chemistry*; D010616:Phenanthrenes / Q000378:metabolism*; D018517:Plant Roots / Q000737:chemistry*; D011721:Pyrenes / Q000378:metabolism*; D053833:Wetlands
chemical_list: D010616:Phenanthrenes; D011721:Pyrenes; C031181:phenanthrene; C030984:pyrene
keywords: Dissolved organic carbon (DOC); Elution; Mangrove; Phenanthrene; Pyrene; Root exudates