저관리형 옥상녹화시스템을 위한 세덤류(Sedums)의 내서성 평가

Heat Tolerance Assessment of Sedums for Extensive Green Roof System

This study as a part of an extensive green roof system development was carried out to assess the heat tolerance of 11 species Sedum spp. on the extensive green roof system: S. kamtschaticum, S. oryzifolium, S. polystichoides, S. sarmentosum, S. acre, S. album, S. reflexum, S. rupestre, S. sexangulare, S. spurium, and S. telephium. Electrolyte leakage evaluation was used to estimate the heat tolerance level of each Sedum at 40°C, 45°C, 47.5°C, 50°C, 52.5°C, 55°C, and 57.5°C. The critical temperatures at the midpoints of sigmoidal curves fitted through electrolyte leakage (EL) were predicted with the range of 54.0°C to 65.2°C. S. album, S. telephium, and S. sexangulare were more tolerant of high temperature than the others. In field condition, the heat tolerance of 11 species Sedum spp. applied to the suggested extensive green roof system was also estimated by EL evaluation. The EL (%) values of 11 species Sedum spp. subjected to maximum temperature (46.7°C) recorded during the experimental periods were lower than 50% except S. kamtschaticum and S. spurium. Especially, S. album, S. rupestre, and S. telephium were ranked higher than the others in heat tolerance. The most Sedum spp. would show good heat tolerance on the extensive green roof system if the maximum temperature on rooftop was below 50°C in summer season.