Research On The Application Of Roof Greening Plants And Landscape And Ecological Value Of Roof Garden In Hangzhou

This paper surveys species and growth of plants in roof gardens in Hangzhou, and the landscape as well. Also, it comparably observes and measures five important ecological elements including temperature, relative humidity, carbon dioxide (CO2) concentration, aero-ions concentration and respirable dust particles (PM10) concentration, from three following aspect: the internal ecosystem of roof garden, the ecosystem of roof garden and bareness roof, and the environment of vertical space around roof garden.The main results are as follows:1. Surveying of the species of plants in 11 roof gardens of 9 buildings in Hangzhou, the result shows that there're 87 species of plants applied including 32 arbors taking 21.8%, 24 shrubs taking 27.6%, 12 herbs taking 13.8%, and 19 others taking 21.8%. There're 19 evergreen arbors taking 59.3% of total arbors, 22 evergreen shrubs taking 91.7% of total shrubs. The application percentage of evergreen trees is comparably higher.2. There're 47 species of plants growing well in roof garden in Hangzhou including 13 arbors, 22 shrubs, 7 herbs, 2 bamboos, 3 climbing plants. And 13 species of plants show less desirable performance in some roof gardens in Hangzhou.3. Via analyzing aesthetic value of three roof gardens in Hangzhou of distinct features, the result indicate that the landscape of roof garden can be well obtained through reasonable plant configuration according to different colors of flowers and leaves, florescence, plant type.4. Contrasting of green land and non-green land in the roof garden, the ecosystem quality from superior to inferior: arbor-shrub-grass pattern> turf-type> flower gallery> garden road.5. The analysis of variance of roof garden, bareness roof, and footway shows that the difference between roof garden and bareness roof, roof garden and footway is apparently distinct, while there's no distinct difference between the latter two, which indicate that the ecosystem of roof garden is obviously superior to another two.6. Contrasting of the green land in roof garden and that on the ground, the result shows that the function of lowering temperature and increasing humidity of roof garden is inferior to that of green land on the ground, while another three indicators (CO2 concentration, aero-ions concentration, PM10 concentration) relating to air quality are better.