title: Historical levels of heavy metals reconstructed from sedimentary record in the Hejiang River, located in a typical mining region of Southern China.
abstract: Historical levels of Pb, Zn, Cd, Cr, Cu, Ni, As, Fe, Al and Mn were found in C1 and C2 sediment cores from the Hejiang River, which is located in a typical mining region of Southern China, the levels date back approximately 57 and 83 years. Temporal variations in the core C1 around the mining peaked in the 1960s, after which they exhibited a decreasing trend, which reflects successful government management. Historical events such as the Pacific War and China's first 5-year economic plan were recorded in core C2, which was collected from the downstream portion of the Hejiang River. Enrichment factors (EF), geo-accumulation (Igeo), and excess flux indicate that severe contamination occurred during the period between 1956 and 1985 due to the release of high amounts of mining waste from human activities around the core C1 region. The highest EF value was displayed by As (67); this was followed by Pb (64), Cd (39), and Zn (35). In contrast, the core C2 sediments exhibited minor pollution because of dilution from tributaries (the Fu River and the Daning River) that do not flow through the mined area and because C2 was farther from the source of the metals. The results of the risk assessment codes (RAC) for both cores indicate that Cd posed a high risk to the local environment. Principal component analysis (PCA) and correlation analysis (CA) revealed that accumulation of heavy metals was mainly due to mining pollution.
authors.affiliation: School of Marine Sciences, Guangxi University, Nanning 530004, China; Coral Reef Research Center of China, Guangxi University, Nanning 530004, China.
authors.forename: Shaopeng
authors.initials: S
authors.lastname: Wang
authors.affiliation: School of Marine Sciences, Guangxi University, Nanning 530004, China; Coral Reef Research Center of China, Guangxi University, Nanning 530004, China. Electronic address: wyh@gxu.edu.cn.
authors.forename: Yinghui
authors.initials: Y
authors.lastname: Wang
authors.affiliation: School of Marine Sciences, Guangxi University, Nanning 530004, China; Coral Reef Research Center of China, Guangxi University, Nanning 530004, China.
authors.forename: Ruijie
authors.initials: R
authors.lastname: Zhang
authors.affiliation: School of Environment, Guangxi University, Nanning 530004, China.
authors.forename: Weitao
authors.initials: W
authors.lastname: Wang
authors.affiliation: School of Environment, Guangxi University, Nanning 530004, China.
authors.forename: Daoquan
authors.initials: D
authors.lastname: Xu
authors.affiliation: School of Environment, Guangxi University, Nanning 530004, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Guo
authors.affiliation: School of Environment, Guangxi University, Nanning 530004, China.
authors.forename: Pingyang
authors.initials: P
authors.lastname: Li
authors.affiliation: School of Marine Sciences, Guangxi University, Nanning 530004, China; Coral Reef Research Center of China, Guangxi University, Nanning 530004, China. Electronic address: kefuyu@scsio.ac.cn.
authors.forename: Kefu
authors.initials: K
authors.lastname: Yu
mesh_terms: D002681:China; D004784:Environmental Monitoring; D019015:Geologic Sediments / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis*; D008906:Mining; D025341:Principal Component Analysis; D045483:Rivers / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*; D014877:Water Pollution, Chemical / Q000706:statistics & numerical data
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: (210)Pb dating; Contamination history; Heavy metals; Hejiang River; Mining region; Sediment cores