Seasonal Variation in Recovery Process of Rainwater Retention Capacity for Green Roofs

Abstract

Green roofs need to quickly recover their water retention capacity between rainfall events to maintain their rainwater retention performance. In this study, the authors observed the rainwater retention, recovery process, and plant eco-physiological performance of green roofs with four local vegetation species under a typical subtropical monsoon climate for two years. The half-life of the water content after each rainfall (T50) was used to describe the recovery rate. The results indicate that (1) the decline in the water content after rainfall can be well described by an exponential decline curve (R2 > 0.7), and the average T50 of green roofs with Plectranthus prostratus Gürke was the shortest among the four plants; (2) the T50 in the wet season was significantly shorter than that in the dry season (p P. prostrates was found to be the best choice in the study.

Keywords

• green roof
• rainwater retention
• recovery process
• seasonal variation
• weather condition
• plant eco-physiology