Coberturas ajardinadas: Influência dos substratos na gestão de águas pluviais

Mestrado em Engenharia de Sistemas Bioenergéticos - Instituto Superior de AgronomiaIn this study the influence of green roofs’ growing medium on stormwater management was evaluated, relatively to the amount of water that can be retained by them, and the quality of stormwater runoff. For this purpose, three growing mediums were analyzed, one of which was implemented on a modern intensive green roof headquartered in Philadelphia, and the other two implemented in Calouste Gulbenkian Foundation classic intensive green roof, whereas one of them is the original growing medium of the project and the other was renovated for about one year. Although there were differences between the physical properties of the growing mediums, any of them exhibited a good water holding capacity. To analyze the stormwater runoff quality, were identified the concentrations of nutrients (N, P and K) and heavy metals (Cd, Pb, Cu, Cr, Ni and Zn) present in the rainwater and the water runoff, ascertaining if these were retained or leached by the growing mediums. Given the discrepancy in results between the growing media and between the elements leached or retained on each growing media, this study clearly indicates that further research is needed to determine the influence of green roofs in the quality of stormwater runoff