@article{LIANG2026, 
author = {Linlin LIANG and Xinze GENG and Feng LIN and Xiaoru LIU and Liping MA and Kun LI and Leixiang WU and Chang LIU and Xuyan LIU and Hongbing CHENG and Yusi LIU},
title = {Comparison of PM2.5 Pollution during Heating and Non-Heating Periods in Northwest China: Chemical Characteristics, Secondary Contribution, and Regional Transport},
year = {2026},
journal = {Journal of Meteorological Research},
volume = {40},
number = {2},
pages = {605-618},
keywords = {air pollution, PM2.5, secondary aerosol, Xinjiang Uygur Zizhiqu, heating, regional transport},
url = {https://www.sciopen.com/article/10.1007/s13351-026-5155-0},
doi = {10.1007/s13351-026-5155-0},
abstract = {Atmospheric pollution in heating season remains a persistent and acute challenge in Xinjiang Uygur Zizhiqu (hereafter Xinjiang), Northwest China, where a prolonged winter heating season prevails. In this study, continuous collection and chemical composition analysis of PM2.5 were conducted from May 2021 to April 2022 in Changji, Xinjiang. Separated by typical non-heating period (May to October) and heating period (November to April of the next year), the concentration of PM2.5 exhibited a substantial increase, rising from 23.3 ± 9.29 µg m−3 during the non-heating period to 98.4 ± 75.2 µg m−3 during the heating period. The concentrations of most water-soluble ion components in PM2.5 during the heating period significantly exceeded those during the non-heating period, especially for secondary inorganic aerosols, such as sulfate ( SO42−), nitrate ( NO3−), and ammonium ( NH4+), which increased by 8.40, 7.47, and 6.55 times, respectively. In contrast, the concentrations of Mg2+ and Ca2+ remained relatively stable across the two periods. During the heating period, the concentration of liquid water content (LWC) was averaged at 4.28 ± 4.07 µg m−3,8.23 times higher than those during the non-heating period (0.52 ± 0.48 µg m−3). This enhanced LWC during the heating period provides a reactive medium for the oxidation ( SO42−) of SO2, with 2–3 times reaction rates higher than that during the non-heating period. Notably, the sulfur oxidation ratio (SOR) likely follows a segmented linear growth pattern during the heating season. Specifically, when LWC exceeds the threshold of 10 μg m−3, the formation rate of  SO42− shifts to a slower linear growth trend. Moreover, regional transport dominates local primary component (e.g., elemental carbon) variations, while surrounding areas of Changji contributed more significantly to secondary components (notably  NO3−) during the heating period.}
}