Evaluation of Air ion Quality in Typical Areas of Shapingba District,Chongqing

From November 2013 to August 2014,air ions were monitored by portable air anions tester (AIC1000) in three typical areas (urban commercial areas,urban residential areas and urban forest parks) of Shapingba District,Chongqing.The results showed that monthly variations of positive air ions in urban commercial areas and urban residential areas all presented a "two-peak" pattern,and their negative air ion displayed a "single-peak" pattern,but monthly variations of positive air ions and negative air ions in urban forest parks all exhibited a "single-peak" pattern.The difference of positive air ions among three typical areas was insignificant(P>0.05),but the difference of negative air ions was significant(P<0.01).The concentration of negative air ions was in the order of forest parks (513 negative air ions per cubic centimeter) > residential areas (377 negative air ions per cubic centimeter) > commercial areas (280 negative air ions per cubic centimeter),moreover,ion polarity ratio and air ion assessment index also showed that the air ion quality of urban forest parks was better than that of residential areas,and made people feel comfortable for more time,but the air ion quality of residential areas was better than that of commercial areas.