Temperature-decreasing and Humidity-increasing Effects of Typical Landscape Plants in Suzhou City

Garden trees play an integral role in supporting healthy urban communities as part of ecological system. 13 typical landscape plants, in Suzhou City, were selected to study the correlations among canopy width, vegetation quantity, branching point height and temperature-decreasing and humidity-increasing effects. This paper showed that different garden plants had various temperature-decreasing and humidity-increasing effects. Osmanthus fragrans (Thunb.) Lour., Zelkova schneideriana Hand.-Mazz., Cinnamomum porrectum (L.) Presl, Magnolia grandiflora L., Pinus massoniana Lamb., Ligustrum Lucidum Ait. and Diospyros Kaki Thunb. had more higher capacity, Platanus acerifolia Willd. and Pinus bungeana Zucc. were a little lower, and Bischofia polycarpa (Levl.) Airy-Shaw, Eriobotrya japonica (Thunb.) Lindl., Albizia julibrissin Durazz. and Liquidambar formosana Hance had the more lower effects on temperature-decreasing and humidity-increasing. Statistics showed that there was a significant positive correlation between the average canopy width and temperature-decreasing and humidity-increasing effects. Vegetation quantity and temperature-lowering had a significant positive correlation, in contrast, the vegetation quantity and humidity-increasing had not a significant positive correlation. Branching point height had effect to decrease temperature and humidity with a certain range.