One century of air deposition of hydrocarbons recorded in travertine in North Tibetan Plateau, China: Sources and evolution.
The characteristic distribution patterns of hydrocarbons have been used for fingerprinting to identify their sources. The historical air depositions of hydrocarbons recorded in natural media help to understand the evolution of the air environment. Travertine is a natural acceptor of air deposition that settles on the ground layer by layer. To reconstruct the historical air environment of hydrocarbons in the North Tibetan Plateau (NTP), a unique background region, twenty-seven travertine samples were collected systematically from a travertine column according to its precipitated year. For each sample, the precipitated year was dated while n-alkanes and polycyclic aromatic hydrocarbons (PAHs) were determined. Based on source identification, the air environment of hydrocarbons in the past century was studied for the region of NTP. Before World War II, the anthropogenic sources of hydrocarbons showed little influence on the air environment. During World War II and China's War of Liberation, hydrocarbons increased significantly, mainly from the use of fossil fuels. Between 1954 and 1963, hydrocarbons in the air decreased significantly because the sources of petroleum combustion decreased. From the mid-1960s through the end of the 1990s, air hydrocarbons, which mainly originated from biomass burning, increased gradually because agriculture and animal husbandry were developing steadily in Tibet and China. From the late 1990s, hydrocarbons in the atmosphere increased rapidly due to the rapid increase of tourism activities, which might increase hydrocarbon emissions from traffic. The reconstruction of the historical air hydrocarbons in NTP clearly reflects the evolution of the region and global development.
State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Beijing 100083, China; School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China. Electronic address: yuangl@cugb.edu.cn.
Guo-Li
GL
Yuan
School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
Ming-Zhe
MZ
Wu
School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
Yong
Y
Sun
School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
Jun
J
Li
School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
Jing-Chao
JC
Li
School of the Earth Sciences and Resources, China University of Geosciences, Beijing 100083, China.
Gen-Hou
GH
Wang
D000393:Air Pollutants / Q000032:analysis*; D000397:Air Pollution / Q000706:statistics & numerical data*; D001272:Atmosphere / Q000737:chemistry; D002681:China; D004784:Environmental Monitoring; D052638:Particulate Matter / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D018609:Tibet
D000393:Air Pollutants; D052638:Particulate Matter; D011084:Polycyclic Aromatic Hydrocarbons
Air deposition; Historical record; Hydrocarbons; Source identification; Tibetan Plateau; Travertine