Effects of biochar usage and plant species selections on the storm water runoff mitigations by green roofs

Abstract

This paper describes an experiment that investigates the influence of plant species choices and the impact of mixing biochar in growing mediums on the amount of water runoff from a simulated green roof. We also measured drought tolerance of different plant species with visual rating method. We found that water runoff mitigation capacities under 100 mm/h rain simulations were higher in Lolium multiflorum Lam compared to Imperata cylindrica (L.) Beauv. and sedum species probably due to differences in their biomass and transpiration rate. We also found that mixing biochar in growing mediums may not change drought tolerance of grass species.