Influence of meteorological and ambient air quality factors on pollen counts in Urumqi, Northwest China.

The exposure of pollen in the air to humans causes adverse allergenic effects on the respiratory system. However, the relationship between pollen counts and meteorological and air quality factors in the arid and semiarid cities of northwest China has not attracted significant attention. Here, we observed the seasonal pollen counts of , as well as the main meteorological variables (temperature/T, relative humidity/RH, and wind speed/WS, and ambient air quality factors (PM, PM, and CO). This was conducted from May to September 2021 at three sampling sites in Urumqi, Xinjiang. The results showed that pollen counts gradually increased from May (121 grains/1000 mm) to August (563 grains/1000 mm) and decreased till the end of the sampling period in September (247 grains/1000 mm). Pearson correlation analysis revealed a significant positive correlation between the variation in pollen counts and PM (R = 0.545, P < 0.01), the average temperature (R = 0.424, P < 0.05), and PM (R = 0.466, P < 0.05). Oppositely, a significant negative correlation was observed between the RH (R = 0.503, P < 0.01) and WS (R = 0.653, P < 0.01). Variation partitioning analysis showed that meteorological factors contributed the highest (44 %) to the variation in pollen counts. The study results provide basic information for future case studies on allergenic plant pollen in Urumqi and serve as a reference for the development of sustainable healthy cities in arid regions.