http://stream.publicbroadcasting.net/production/mp3/wamc/local-wamc-960719.mp3
Albany, NY – In today's Academic Minute, Dr. Mark Simmons of the University of Texas at Austin outlines the benefits of green roof technology.
Dr. Mark Simmons is a research ecologist at the Lady Bird Johnson Wildflower Center, at the University of Texas at Austin. His research interests include applying ecological and ecophysiological mechanisms to specific conservation, restoration and environmental problems, as well as the manipulation, conservation, restoration and regeneration of ecosystems. He holds a Ph.D. from Texas A&M University.
Dr. Mark Simmons - Green Roofs
A green roof is a flat or gently sloping roof with vegetation growing on it. Their benefits include the ability to help cool buildings and reduce the urban "heat-island" effect. They can capture and even filter impurities out of stormwater that falls on roof vegetation - preventing pollutants from reaching creeks and other water sources. And they provide aesthetic beauty and habitat for wildlife.
However, so far little attention has focused on how green roofs are made or their use in warmer climates, where they have the most potential. We have shown that green roofs can perform well in warmer climates where high temperatures and flash floods are common. We have also found that green roof components have a big impact on their ability to cool a building's interior and clean stormwater of impurities.
Warm climates are challenging because they expose plants to high temperatures and high rates of water loss. We are refining the design of several green roof types for Texas and for other subtropical regions. This includes considering using native plants that are adapted to warmer weather, and determining how best to retain moisture using irrigation or spongy layers inside the green roof media. Because climate varies across subregions, suitable plants will need to be found for green roofs in each area.
Finally, more sustainable green roof materials and techniques need to be developed. These include improved irrigation methods, smaller drainage layers, and incorporating organic matter into the soil media.