Ozone response of Sedum species commonly used for green roofs

Abstract

We evaluated O₃ response of nine Sedum species commonly used for green roofs. Plants were exposed to O₃ with 120 ppb once a week for two months. O₃ responses of dry mass, which were mainly caused by those of photosynthetic nitrogen utilization efficiency, differed among the Sedum species, but the responses were at most ±10%. Plant cover decreased with O₃ exposure, but the decrease was at most about 15%. Our results show that green roofs using Sedum species are likely to be sustainable under urban environment where warning for photochemical smog is issued about once a week.