BS, Kent State University, 2020, College of Arts and Sciences / Department of Biological Sciences
The increasing urbanization of land has produced expansive amounts of impervious surfaces, yielding greater quantities of runoff. This runoff can carry pollutants from the surrounding area into the water system and negatively impact the water quality. A possible solution for reducing runoff from impervious surfaces is green roofs, which can absorb and filter water. To determine a green roof's effects on water quantity and quality, an experimental green roof was studied in Cleveland, Ohio. This site contains 39 test plots that differ in combinations of plant community type (restoration or horticultural), substrate type (quasi-traditional, conventional, or open space), and the presence of mycorrhizal inoculum. From October 2017 to October 2018, water samples were collected bimonthly, along with volumetric measurements of the runoff present. The samples were tested for inorganic phosphorus and total inorganic nitrogen using nutrient assays on a microplate reader. Over the duration of the experiment, total inorganic nitrogen fluxes and concentrations were too low to be of concern. Inorganic phosphorus fluxes and concentrations were initially high, but decreased as the roof aged. Building and collection materials were analyzed for phosphorus leaching, but results rather showed possible phosphorus adsorption to certain materials. Inorganic phosphorus was most heavily influenced by substrate type and may be reduced by the use of natural, non-fertilized substrates. Total inorganic nitrogen was most heavily influenced by the biological components (plant community, mycorrhizae), and may be reduced by the presence of mycorrhizae. Manipulating design aspects of green roofs may increase their potential to be improved and refined into an efficient environmental resource.
Committee: Christopher Blackwood Ph.D. (Advisor); David Costello Ph.D. (Committee Member); Reid Coffman Ph.D. (Committee Member); Mark Kershner Ph.D. (Committee Member)
Subjects: Biology; Ecology; Environmental Engineering; Environmental Science; Sustainability