Undergraduate Research & Mentoring Program

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Roofing -- Design and construction -- Environmental aspects, Green roofs (Gardening)-- Design and construction


An important ecosystem service provided by greenroofs is evaporative cooling. Although rates of evapotranspiration are being more frequently reported in the literature, more information for different geographic regions is needed. Even less is known about the role of irrigation in this scenario. In this study, green roof cooling effects on the surrounding environment are analyzed by calculating evapotranspiration for a known drainage area of a green roof in Houston TX. This greenroof, located on NASA’s Johnson Space Center, is divided into two areas with different plant communities; a total of 20 moisture sensors were installed evenly in each region in 2014 in addition to a weather station. The sum total precipitation in 2014 was 992.6mm. The sensors located nearest the roof drain reported moisture content ranging from 15.40- 25.37 % vwc. Those furthese from the roof drain reported ranges from 10.08-29.33 % vwc. Moisture content intermediate of these two zones range from 11.51-31.49 % vwc. Areas planted in different plant communities spanned these different moisture zones; annual evapotranspiration totals were calculated as 117.57 and 166.35mm on average for areas planted in non-native and native communities, respectively. Ongoing work will compare these rates of evapotranspiration to modeled predictions, using weather station data and the FAO Penman-Monteith equation, to consider different irrigation strategies for this roof.


The project abstract is located below in Additional Files

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sonashi.pdf (574 kB)
Project Abstract

Available for download on Sunday, October 01, 2017