title: Deposition and regional distribution of HCHs and p,p'-DDX in the western and southern Tibetan Plateau: records from a lake sediment core and the surface soils.
abstract: Tibetan Plateau is the world's highest plateau, which provides a unique location for the investigation of global fractionation of organochlorine pesticides (OCPs). In this study, deposition and regional distribution of HCHs and p,p'-DDX in the western and southern Tibetan Plateau were investigated by the records from a sediment core of Lake Zige Tangco and 24 surface soils. Concentration of ΣHCHs in the surface soils of the western Tibetan Plateau was much higher than that of the southern part. Maximum fluxes of α-, β-, and δ-HCH in the sediment core were 9.0, 222, and 21 pg cm(-2) year(-1), respectively, which appeared in the mid-1960s. Significant correlations were observed between concentrations of α- and β-HCH in both the surface soils and the sediment core. Concentrations of both α- and β-HCH increased with the inverse of the average annual temperature of these sites. γ-HCH became the dominant isomer of HCHs after the late 1970s, and reached the maximum flux of 160 pg cm(-2) year(-1) in the early 1990s. There were no significant correlations between concentrations of γ-HCH and the other isomers in both the surface soils and the sediment core. The results suggested that there was input of Lindane at scattered sites in this area. In contrast to ΣHCHs, concentration of Σp,p'-DDX in the surface soils of the southern part was much higher than that of the western part. Maximum flux of Σp,p'-DDX was 44 pg cm(-2) year(-1), which appeared in the mid-1960s. Local emission of p,p'-DDT was found at scattered sites. This study provides novel data and knowledge for the OCPs in the western and southern Tibetan Plateau, which will help understand the global fractionation of OCPs in remote alpine regions.
authors.affiliation: State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing, 210008, China. yqtao@niglas.ac.cn.
authors.forename: Yu-Qiang
authors.initials: YQ
authors.lastname: Tao
authors.affiliation: College of Geographical Sciences, Fujian Normal University, Fuzhou, 350007, China.
authors.forename: Guo-Liang
authors.initials: GL
authors.lastname: Lei
authors.affiliation: State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing, 210008, China. bxue@niglas.ac.cn.
authors.forename: Bin
authors.initials: B
authors.lastname: Xue
authors.affiliation: State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing, 210008, China.
authors.forename: Shu-Chun
authors.initials: SC
authors.lastname: Yao
authors.affiliation: School of Remote Sensing, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Pu
authors.affiliation: College of Tourism and Geography Sciences, Yunnan Normal University, Kunming, 650092, China.
authors.forename: Hu-Cai
authors.initials: HC
authors.lastname: Zhang
mesh_terms: D003634:DDT / Q000032:analysis; D003633:Dichlorodiphenyl Dichloroethylene / Q000032:analysis*; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments / Q000737:chemistry*; D001556:Hexachlorocyclohexane / Q000032:analysis; D006843:Hydrocarbons, Chlorinated / Q000032:analysis; D060106:Lakes / Q000737:chemistry*; D010575:Pesticides / Q000032:analysis; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D018609:Tibet; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D006843:Hydrocarbons, Chlorinated; D010575:Pesticides; D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; C086916:delta-hexachlorocyclohexane; D003633:Dichlorodiphenyl Dichloroethylene; D001556:Hexachlorocyclohexane; D003634:DDT; C023888:beta-hexachlorocyclohexane