Abstract:

To evaluate the concentration of air negative ions (NAI) and their air quality in spring, summer, autumn and winter in ten forest leisure health areas of Shengzhou City, Zhejiang Province, from June 2016 to June 2019, air negative ions were measured at 30 monitoring points in ten forest leisure health areas of the city by NT-C101A portable air positive and negative ion measuring instrument. The results showed that: (1) the average negative ion concentration of the ten forest leisure health areas in Shengzhou was 6668/cm³, and more than 6 times higher than that of the world health organization clean air standard; (2) the seasonal distribution of NAI concentration in the ten forest leisure health areas in Shengzhou was characterized by summer> spring and autumn> winter; (3) there were significant differences in the concentration of negative air ions in different forest recreation areas, among them, the concentration of negative air ions was the highest at the monitoring point close to falling water, and the instantaneous determination of the highest concentration was 67800/cm³; (4) NAI had a significantly positive correlation with air relative humidity and temperature, but non-significantly negative correlation with PM_2.5 concentration. The ten forest leisure health areas in Shengzhou are rich in air negative ion resources, with obvious seasonal changes, higher in summer and lower in winter. The change of NAI concentration is affected by the environmental factors such as humidity, temperature and PM_2.5 in the air. The dense forest vegetation resources and abundant water resources in Shengzhou are the determinants of its clean and comfortable air, which is beneficial to human health, and the prospect of developing forest health industry is promising.

Key words: air negative ions (NAI), Shengzhou City, forest leisure health area, air quality, PM_2.5, forest health, forest city