Abstract:

In order to select the plant species suitable for rain garden in the semi-arid and semi-humid region of northwest China, based on the analysis of domestic and foreign research, we conducted a field survey on the typical rain garden in Xixian New Area located in the semi-arid and semi-humid region of northwest China, and comprehensively evaluated 76 species planted in the rain garden from the aspects of ecological, ornamental and functional characteristics by adopting the analytic hierarchy process, and built the evaluation system from 3 criterion layers and 10 index layers. The results showed that: 4 indexes of rainwater interception ability, stress tolerance ability, florescence color and water purification ability had the greatest influence on the plant selection for rain garden; Ligustrum vicaryi, Melilotus albus, Lythrum salicaria had the best suitability, but Zephyranthes candida, Oxalis corniculata, Sedum lineare were the worst. According to the types and water storage of rain garden, we put forward the plant types suitable for the marginal zone, buffer zone and storage zone respectively, and summarize the principle of plant selection in rain garden as well. The results could provide a basis for plant suitability selection of rain garden in the semi-arid and semi-humid region of northwest China.

Key words: semi-arid and semi-humid region, sponge city, rain garden, plant selection, suitability evaluation