Effect of root exudates on sorption, desorption, and transport of phenanthrene in mangrove sediments.
The effect of root exudates on the environmental behaviors of phenanthrene in mangrove sediments is poorly understood. In order to evaluate their influence, comprehensive laboratory experiments were performed using batch equilibrium and thin-layer chromatography (TLC) analyses. In the presence of root exudates, sorption of phenanthrene was inhibited, whereas desorption and mobility were promoted, and were elevated as root exudate concentrations increased. Among the three representative low molecular weight organic acids (LMWOAs) (citric, oxalic, and acetic acids), citric acid promoted desorption and mobility of phenanthrene more effectively than the other two. In addition, application of artificial root exudates (AREs) enhanced phenanthrene desorption, and mobility was always lower than that with the same concentration of LMWOAs, suggesting that LMWOAs predominantly affected the fate of phenanthrene in sediments. The results of this study could enhance our understanding of the mobility of persistent organic pollutants in sediment-water system.
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China.
Hui
H
Jia
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China.
Haoliang
H
Lu
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China.
Minyue
M
Dai
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China.
Hualong
H
Hong
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China.
Jingchun
J
Liu
Key Laboratory of Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, PR China. Electronic address: ycl@xmu.edu.cn.
Chongling
C
Yan
D019342:Acetic Acid / Q000737:chemistry; D000327:Adsorption; D002681:China; D019343:Citric Acid / Q000737:chemistry; D019015:Geologic Sediments / Q000737:chemistry*; D008970:Molecular Weight; D019815:Oxalic Acid / Q000737:chemistry; D010616:Phenanthrenes / Q000032:analysis / Q000493:pharmacokinetics*; D053147:Plant Exudates / Q000737:chemistry*; D018517:Plant Roots / Q000737:chemistry / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics*; D053833:Wetlands
D010616:Phenanthrenes; D053147:Plant Exudates; D014874:Water Pollutants, Chemical; D019343:Citric Acid; C031181:phenanthrene; D019815:Oxalic Acid; D019342:Acetic Acid
Desorption; Mangrove sediments; Mobility; Phenanthrene; Root exudates; Sorption