title: Identification of traffic-related metals and the effects of different environments on their enrichment in roadside soils along the Qinghai-Tibet highway.
abstract: The road transportation could affect roadside soils environment detrimentally, including heavy metal enrichment. In order to identify and evaluate the enrichment of heavy metals resulted from road transportation on the Tibetan Plateau, the 11 heavy metals (V, Cr, Co, Ni, Cu, Zn, As, Cd, Rb, Pb and Tl) in the topsoil (0-10 cm depth) from four sites along the Qinghai-Tibet highway were discussed in this study. Our results indicate that heavy metals such as Cr, Cu, Zn, As, Cd and Pb are related to road transportation. The content of most of these heavy metals in roadside soils decreased exponentially with the distance from the road, as did some of the Nemero Synthesis Indexes (PN values). The contamination factor for the traffic-related metals ranged from 0.56 (no pollution) to 5.67 (considerable pollution) and the Nemero Synthesis Indexes of these heavy metals ranged from 0.80 (no pollution) to 4.49 (severe pollution). Cd was of priority concern as it had the highest contamination factor. The highest PN value for these traffic-related heavy metals was found in soils at site TTH (alpine steppe). Although transportation contributed to the high contents of these traffic-related metals in roadside environments, regional differences such as wind and the terrain also had significant relationship with their enrichment in these roadside soils. The roadside distance at which there is a potential risk to livestock and wildlife from the contamination of soils by heavy metals should be determined scientifically along the Qinghai-Tibet highway, based on the different natural environments found in the region.
authors.affiliation: Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resource Research, Chinese Academy of Sciences (CAS), Beijing 100101, China; Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resource Research, Chinese Academy of Sciences (CAS), Beijing 100101, China.
authors.forename: Zhaofeng
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resource Research, Chinese Academy of Sciences (CAS), Beijing 100101, China; CAS Center for Excellence & Innovation in Tibetan Plateau Earth System Sciences, Beijing 100101, China. Electronic address: zhangyl@igsnrr.ac.cn.
authors.forename: Yili
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China.
authors.forename: Mingjun
authors.initials: M
authors.lastname: Ding
authors.affiliation: Key Laboratory of Poyang Lake Wetland and Watershed Research, Ministry of Education, Jiangxi Normal University, Nanchang 330022, China.
authors.forename: Lanhui
authors.initials: L
authors.lastname: Li
mesh_terms: D004784:Environmental Monitoring; D019216:Metals, Heavy / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D018609:Tibet; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants; D001335:Vehicle Emissions
keywords: Qinghai–Tibet highway; Road transportation; Soil pollution; Tibetan Plateau; Traffic-related metals