Dissertation Research:The Fate of Nitrate in Stormwater Retention Basins in an Arid Metropolitan Area

蓄水池是管理暴雨过多水的一种常见方法。在有蓄水池的社区，来自特定区域的所有径流都被引导到一个凹陷的区域，在那里水可以渗透到土壤中或蒸发。许多研究表明，雨水往往含有高浓度的营养物质和其他污染物，但很少有研究，特别是在干旱环境中，研究这些添加对土壤微生物过程的影响。在这个项目中，将在两种类型的蓄水池中模拟一场风暴，蓄水池将被含有稀有氮同位素的水淹没。使用同位素可以追踪氮被微生物转化为各种化合物的过程，其中一些化合物比其他化合物是更严重的污染物。雨水蓄水池是管理和规划的天然单位，因此，这项研究除了对城市系统的生态理论做出贡献外，还具有更广泛的影响。从这项工作中获得的见解将直接造福社会：规划者、工程师和管理人员将更好地了解流域设计如何影响土壤改善水质和减少潜在温室气体排放的能力。对城市的生态过程和城市内部的生态过程有足够的了解，这对于城市生态和社会经济系统未来的可持续性是必要的。

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.