Resource investigation of roof greening native plant of Chongqing main city and its landscape application analysis

Plant diversity is important component of biodiversity, and garden plants are the main parts of urban ecological system. The maintenance of urban biodiversity depends on the diversity of urban plants, native plants are important part of urban plants, even the necessary condition of making characteristics of urban plant landscape. As for the abundant resources of native plants in Chongqing of southwestern China, aim at weakness in the application of native plants in roof greening, we did survey of 31green roofs of central districts of Chongqing by sample survey. We got that there were 110 species of plants. Then we summarized and analyzed the characteristics of roof plants in application and configuration, frequency, ornamental value and so on. But native plants only accounted for about 13.64%. After summarized datum in the 3 levels, we got a phanomenon that the species and application frequency of native plants are relatively few. Therefore, the staffs should attach importance to native plants. It is imperative to exploit native plants. Based on the results, a list of native plants for developing and popularizing were suggested. We should be aware of their characteristics and gradually being applied to roof greening. Finally, the strategy and suggestion are proposed on the protection and exploitation of native plant resources, and the construction of urban green space using these resources in Chongqing City.