Journal article

Laboratory Tests of Substrate Physical Properties May Not Represent the Retention Capacity of Green Roof Substrates In Situ

Christopher Szota, Tim D Fletcher, Carine Desbois, John P Rayner, Nicholas SG Williams, Claire Farrell

WATER | MDPI | Published : 2017


Green roofs can be used to reduce the volume of polluted stormwater that is generated by cities. Modelling rainfall retention is critical, but green roof water balance models often rely on the physical properties of substrates. In these models, substrate water holding capacity (WHC) determines the depth of water which can be stored before runoff is generated; whereas, the permanent wilting point (PWP) limits evapotranspiration. The WHC and PWP, as well as plant available water (PAW; where PAW = WHC - PWP), as determined from laboratory tests, may not truly reflect how substrates perform on green roofs. We therefore ran a simulated rainfall experiment on green roof modules to (i) compare the ..

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Awarded by Australian Research Council - Victorian Department of Sustainability and Environment

Awarded by ARC

Funding Acknowledgements

We thank Ruth Mitchell and Ross Payne for assistance developing the green roof modules and irrigation. Ruth also assisted with measurements, as did Beau Picking. Thanks to Nick Osborne and Sascha Andrusiak for technical assistance. This research was funded by Australian Research Council Linkage Grants (LP0990704 and LP130100731), supported by the Victorian Department of Sustainability and Environment, Melbourne Water, City of Melbourne, and The Committee for Melbourne. T.D. Fletcher was supported by an ARC Future Fellowship (FT100100144).