Retention basins are a common approach to managing excess water from rain storms. In neighborhoods with retention basins, all of the runoff from a given area is directed into a recessed area where the water can then infiltrate into the soil or evaporate. Many studies have shown that stormwater often has high concentrations of nutrients and other pollutants, but few studies, especially in arid environments, have investigated the impacts of these additions on soil microbial processes. For this project, a storm will be simulated in two kinds of retention basins, which will be flooded with water containing a rare isotope of nitrogen. The use of the isotope enables tracking the nitrogen as it is transformed by microorganisms into various compounds, some of which are more serious pollutants than others. Stormwater retention basins are a natural unit for management and planning, thus this research has a broader impact beyond contributing to ecological theory of urban systems. Insights from this work will create a direct benefit to society: planners, engineers, and managers will better understand how basin design influences the ability of the soils to improve water quality and reduce potential greenhouse gas emissions. Sufficient knowledge of ecological processes of and within cities is necessary for the future sustainability of urban ecological and socioeconomic systems.
