Importance of local non-fossil sources to carbonaceous aerosols at the eastern fringe of the Tibetan Plateau, China: Δ14C and δ13C evidences

Chaoliu Li; Chao Zhang; Fangping Yan; Shichang Kang; Yinbo Xu; Yixi Liu; Yongheng Gao; Pengfei Chen; Cenlin He

doi:10.1016/j.envpol.2022.119858

Importance of local non-fossil sources to carbonaceous aerosols at the eastern fringe of the Tibetan Plateau, China: Δ¹⁴C and δ¹³C evidences

Environ Pollut. 2022 Oct 15:311:119858. doi: 10.1016/j.envpol.2022.119858. Epub 2022 Aug 11.

Authors

Chaoliu Li¹, Chao Zhang², Fangping Yan³, Shichang Kang⁴, Yinbo Xu⁵, Yixi Liu⁴, Yongheng Gao⁶, Pengfei Chen³, Cenlin He⁷

Affiliations

¹ State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100039, China. Electronic address: lichaoliu@nieer.ac.cn.
² State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China; University of Chinese Academy of Sciences, Beijing, 100039, China.
³ State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
⁴ State Key Laboratory of Cryospheric Sciences, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100039, China.
⁵ School of Geographical Sciences, Southwest University, Chongqing, 400045, China.
⁶ Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, China.
⁷ Research Applications Laboratory, National Center for Atmospheric Research, Boulder, CO, 80301, USA.

PMID: 35964790
DOI: 10.1016/j.envpol.2022.119858

Abstract

Carbonaceous particles are an important radiative forcing agent in the atmosphere, with large temporal and spatial variations in their concentrations and compositions, especially in remote regions. This study reported the Δ¹⁴C and δ¹³C of total carbon (TC) and water-insoluble particulate carbon (IPC) of the total suspended particles (TSP) and PM_2.5 at a remote site of the eastern Tibetan Plateau (TP), a region that is influenced by heavy air pollution from Southwest China. The average organic carbon and elemental carbon concentrations of TSP samples in this study were 3.20 ± 2.38 μg m^-3 and 0.68 ± 0.67 μg m^-3, respectively, with low and high values in summer and winter, respectively. The fossil fuel contributions of TC in TSP and PM_2.5 samples were 18.91 ± 7.22% and 23.13 ± 12.52%, respectively, both of which were far lower than that in Southwest China, indicating the importance of non-fossil contributions from local sources. The δ¹³C of TC in TSP samples of the study site was -27.06 ± 0.96‰, which is between the values of long-range transported sources (e.g., Southwest China) and local biomass combustion emissions. Therefore, despite the contribution from the long-range transport of particles, aerosols emitted from local biomass combustion also have an important influence on carbonaceous particles at the study site. The findings of this work can be applied to other remote sites on the eastern TP and should be considered in related research in the future.

Keywords: Biomass combustion; East Tibetan Plateau; Sources; Water-insoluble particulate carbon; Δ(14)C and δ(13)C.

MeSH terms

Aerosols / analysis
Air Pollutants* / analysis
Carbon / analysis
China
Environmental Monitoring
Particulate Matter* / analysis
Seasons
Tibet

Substances

Aerosols
Air Pollutants
Particulate Matter
Carbon