Rank of negative oxygen ion content in Wuzhishan, Hainan

the content of negative oxygen ions in Wuzhishan of Hainan ranks in the top ten. According to the comprehensive index evaluation of urban ambient air quality, the top ranked cities and counties in Hainan Province are Ledong County, Wuzhishan City, Baoting County, Wanning County, Changjiang County, Qiongzhong County, Qionghai County, Haikou City and Baisha County. Negative oxygen ion is a single gas molecule and hydrogen ion group with negative charge, which plays a regulatory role in air purification and urban microclimate, and its concentration level is one of the indicators of urban air quality evaluation.