Abstract
PM2.5 (particulate matter with an aerodynamic diameter <2.5 μm) samples (n = 58) collected every sixth day in Xi’an, China, from 5 July 2008 to 27 June 2009 are analyzed for levoglucosan (1,6-anhydro-β-d-glucopyranose) to evaluate the impacts of biomass combustion on ambient concentrations. Twenty-four-hour levoglucosan concentrations displayed clear summer minima and winter maxima that ranged from 46 to 1889 ng m−3, with an average of 428 ± 399 ng m−3. Besides agricultural burning, biomass/biofuel combustion for household heating with straws and branches appears to be of regional importance during the heating season in northwestern China. Good correlations (0.70 < R < 0.91) were found between levoglucosan relative to water-soluble K+, Cl−, organic carbon (OC), elemental carbon (EC), and glyoxal. The highest levoglucosan/OC ratio of 2.3% was found in winter, followed by autumn (1.5%). Biomass burning contributed to 5.1–43.8% of OC (with an average of 17.6 ± 8.4%).
Implications: PM2.5 levoglucosan concentrations and the correlation between levoglucosan relative to other compounds during four seasons in Xi’an showed that the influence of biomass burning is maximum during the residential heating season (winter), although some important influences may be detected in spring (field preparation burnings) and autumn (corn stalks and wheat straw burning, fallen dead leaves burning) at Xi’an and surrounding areas. Household heating with biomass during winter was quite widespread in Guanzhong Plain. Therefore, the control of biomass/biofuel combustion could be an effective method to reduce pollutant emission on a regional scale.
Additional information
Notes on contributors
Ting Zhang
Ting Zhang and Sui-Xin Liu are engineers, and Jun-Ji Cao, Steven Sai Hang Ho, Yong-Ming Han, and Ge-Hui Wang are professors for the SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, People’s Republic of China.
Jun-Ji Cao
Ting Zhang and Sui-Xin Liu are engineers, and Jun-Ji Cao, Steven Sai Hang Ho, Yong-Ming Han, and Ge-Hui Wang are professors for the SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, People’s Republic of China.
Judith C. Chow
Judith C. Chow and John G. Watson are research professors in Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA.
Zhen-Xing Shen
Zhen-Xing Shen is a professor at the Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an, People’s Republic of China.
Kin-Fai Ho
Kin-Fai Ho is a professor at the Jockey Club School of Public Health and Primary Care, the Chinese University of Hong Kong, Hong Kong SAR, People’s Republic of China.
Steven Sai Hang Ho
Ting Zhang and Sui-Xin Liu are engineers, and Jun-Ji Cao, Steven Sai Hang Ho, Yong-Ming Han, and Ge-Hui Wang are professors for the SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, People’s Republic of China.
Sui-Xin Liu
Ting Zhang and Sui-Xin Liu are engineers, and Jun-Ji Cao, Steven Sai Hang Ho, Yong-Ming Han, and Ge-Hui Wang are professors for the SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, People’s Republic of China.
Yong-Ming Han
Ting Zhang and Sui-Xin Liu are engineers, and Jun-Ji Cao, Steven Sai Hang Ho, Yong-Ming Han, and Ge-Hui Wang are professors for the SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, People’s Republic of China.
John G. Watson
Judith C. Chow and John G. Watson are research professors in Division of Atmospheric Sciences, Desert Research Institute, Reno, NV, USA.
Ge-Hui Wang
Ting Zhang and Sui-Xin Liu are engineers, and Jun-Ji Cao, Steven Sai Hang Ho, Yong-Ming Han, and Ge-Hui Wang are professors for the SKLLQG, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an, People’s Republic of China.
Ru-Jin Huang
Ru-Jin Huang is a scientist at Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen, Switzerland.