北京地区植被屋面不同厚度下景天植物组合研究

(目的)本文旨在通过试验研究植物种类多样性对植被屋面的影响，以及基质层厚度对植物生长的作用，以选择适合北京地区气候条件下的植物组合。(方法)试验在真实屋面环境下，对3种景天植物组合在3个基质层厚度下(7、10、15 cm)的生长表现进行研究。测定成活率（返青率）、覆盖度、基质含水量、景观效果及生长势等指标，进而综合评价。(结果)各组合的植物长势、成活率、返青率、基质含量与基质层厚度呈正相关；比较3个植物组合，从各指标表现及多样性方面看，2号（反曲景天、‘胭脂红’景天、光亮假景天）> CK（佛甲草）>1号（六棱景天、石景天、‘红毯’白景天）。(结论)15 cm基质层可为植被屋面的植物提供较好的生长环境；2号组合表现最佳，可在北京地区推广应用。

Crassulaceae Combinations Under Different Depths of Extensive Green Roofs in Beijing

This paper describes an experiment investigating the influence of plants diversity on green roof and the effect of substrate depths on plants survival, in order to select the vegetation types which can adapt to the climate of Beijing. The experiment was conducted under the real rooftop environment, the performances of 3 Crassulaceae combinations were tested on substrates of three different depths (7, 10, 15 cm). Plant survival, coverage, substrate moisture content, visual appearance and growth vigor were measured. It was concluded that deeper substrate promoted higher survival and coverage, better appearance and growth vigor, as well as higher substrate moisture content. By comparing the plant combinations and considering the performance of all indexes and plant diversity, it was found that No.2 (Sedum reflexum, Phedinum spurium‘Coccineum’, P. spurium‘Splendens’) > CK (S. lineare) > No.1 (S. sexangulare, S. acre, S. album‘Coral Carpet’). 15 cm substrate could provide a better growth environment for plants on the extensive green roofs, and No.2 was the best combination which could be widely applied in Beijing.