Comparison Of The Result From Two Airborne Pollen SurveyConducted In Taiyuan City During The Past Thirty-five Years

Objective:To investigate the species, amount and seasonal distribution of airborne pollen and explore the relationship between the type and content of autumn airborne pollen and floors in Taiyuan City.Methods:Daily airborne pollen monitoring was performed by Gravitational Method using Ye’S Sampler in Taiyuan from July2011to June2012, and compared the recent survey result with the result of1977-1978. The samples were separately placed on the well-ventilated building roofs of the4th,7th and17th floors.Results:16999grains of pollen were collected within the period mentioned above in total. Peak value of mensal pollen count was seen in August to September, which was followed by in March to May. Twelve kinds of new airborne pollens were collected in our recent survey, and the pollen of one kind of harmful invasive plants, Ambrosia was shown in our survey. The five kinds of common and abundant pollens accounted for as much as76.72%of total annual pollens amount in1977-1978; the four kinds of common and abundant pollens accounted for as much as74.12%in2011-2012. Artemisia pollen was the most abundant airborne pollens in mount(39.47%). The recent percentage of Populus and Salix pollen decreased obviously, compared to the data of35years before, resulting in peak value of mensal pollen count was seen in summer-autumn instead of spring in2011-2012. The genera of airborne pollens of4th floored buildings and7th floored buildings were approximately the same, while of17th floored buildings were reduced.Conclusions:Global warming was one of the possible major reasons that spring airborne pollens peak started earlier and lasted longer. The type and content of air-borne pollens on the17th (51meters) floor are obviously reduced compared with those of the4th floor and the7th floor. High-rise residential living can reduce the amount of pollen inhalation.