Effects Of Four Garden Plants On Airborne Microbes

In order to explore the inhibition on airborne microbes of garden plants, we investigated the airborne microbes concentration in Cinnamomum camphora, Osmanthus fragrans, Myrica rubra, and Phyllostachys viridis woodlands in East Lake Campus of Zhejiang Forestry university. Using the method of natural sedimentation to momitored dynamics of airborne microbes concentration in different sample plots from December 2007 to November 2008, and estimated the air quality. Results showed that.1,Diurnal variations of airborne bacteria, fungi and actinomycete concentration in four woodlands was regular in different seasons. Aairborne bacteria concentration was higher in the morning and night and at noon, it had the strongest inhibition on airborne bacteria,inhibitory rates was more than 50%. Actinomycete concentration and fungi concentration were relatively low in the morning and night, arrived the highest concentration between 13:00 to 16:00. Fungi and actinomycete concentrations in wooslands were higher than the control between 10:00 to 13:00.2,Annual variations of airborne microbes is the same in four woodlands, airborne bacteria concentration and total microbial concentration were highest in winter,lowest in summer,which in spring were same as in fall;Fungi concentration was highest in spring, lowest in summer; actinomycete concentration was highest in summer, lowest in spring. Four kinds of woodlands could significant inhibit the growth of airborne bacteria, Inhibitory rates of Cinnamomum camphora was less than 50% during the year; Inhibitory rates of Osmanthus fragrans had 6 months more than 50%; Inhibitory rates of Myrica rubra was less than 50% only in May and July; Inhibitory rate of Phyllostachys viridis was higher, except January and May, was more than 50% in the other months. Whereas, Four kinds of woodlands promoted the growth of fungi and actinomycetes,increased by 0.5-2 times compared with the control.3,Plants have a very strong inhibition on airborne bacteria, fungi and actinomycete, and in the horizontal distance, farther away from the plants corresponding to inhibitory rates being weaker. In the vertical distance, airborne bacteria concentration decreased from 0m to 1.5m, and increased from 1.5m to 2.0m. Fungi and actinomycete concentration increased from 0m to 0.5m, then decreased from 0.5m to 1.5m, but increased from 1.5m to 2.0m.4,The extracts of four kinds of plants could inhibit the growth of bacteria, fungi and actinomycetes, and inhibitory ability enhanced corresponding to the extract concentration increasing. The inhibition on airborne microbes from woodlands was the same as the extracts of plant,so results show that the plants could inhibit the growth of airborne microbes by emissing VOCs.The above study shows that ,the effects of four kinds of woodlands on reducing airborne microbes concentration and improving air quality were significant, plants can purify the air by emissing VOCs. So in the future, in addition to consider the color,form and aroma of Osmanthus fragrans, Myrica rubra, and Phyllostachys viridis, proposed better use of its antibacterial ecological value, for a reasonable configuration.