Abstract
This study evaluated evapotranspiration and temperature rise control effect by Carex thunbergii Steud. adopted in rooftop greening. As a result, the consumption of water by evapotranspiration during fine summer weather was approximately 11 l/m2/day in a non-mowed plot. Under equal conditions in a mowed plot, consumption was approximately 5 l/m2/day. Water consumption in the mowed plot was less than one half of the non-mowed plot, and both were 3-4 degrees lower in terms of mean temperature compared with rooftop lawn plot temperatures. The temperature at ground level under fine daytime weather conditions during the summer exhibited a tendency to be lower in the non-mowed plot. Under the same conditions, a tendency toward lower air temperatures after solar noon was seen at ground level in the mowed plot. Based on these results, it is suggested that moderation of the heat island phenomenon is possible through the utilization of a hygrophyte such as Carex thunbergii and simple maintenance procedures such as mowing.
