S07 - Session O1 - Create and manage green cities using crassulacean acid metabolism (CAM) ornamental plants production in rooftop greenhouse

Authors: Yoon Jin Kim *, Ah Ram Cho, Sang Min Lee

Heating and cooling systems in buildings generate a large amount of surplus carbon dioxide (CO 2 ). Recycling surplus CO 2 in a rooftop greenhouse in cities can be a methodology to contribute to green cities. The plants, especially crassulacean acid metabolism (CAM) plants have potential on carbon sink because plants absorb CO 2 and use that for photosynthesis during the night. Through the regeneration of exhausted CO 2 in a building, recycling surplus CO 2 in orchid and potted plants production lowers energy costs because the number and size of leaves increase rapidly, resulting in faster the vegetative phase. Phalaenopsis orchids have ornamental value and require a long cultivation duration, 20-24 months with CO 2 absorption. Kalanchoe is a popular ornamental potted plant that is CAM. The net CO 2 uptake rate and stomatal conductance of Phalaenopsis and Kalanchoe were significantly affected by CO 2 concentration with controlling light and/or nutrients including nitrogen, potassium, and calcium. CO 2 supply in a rooftop greenhouse for both plants can enhance plant growth rate, shorten the growth period, and reduce energy costs associated with air purification environmental issues. Living architecture using CAM ornamental plants can be a part of a new building concept with a rooftop greenhouse system. This work was carried out with a grant (NRF-2018R1A2B6007834) from Nation Research Foundation of Korea.