Relating Vegetation Composition in a Bioretention Cell to Small-ScaleHydrologic and Topographic Variability

摘要

Bioretention cells have gained favor as a stormwater best management practice (BMP) in areas with suburban or moderate urban development. Despite their popularity, the complex interaction between vegetation, hydrology, and treatment efficacy in these systems is generally not well understood. This paper presents preliminary results of a multi-year study of a bioretention cell in Northeastern Kansas. During the study period, stormwater influent and effluent quality and quantity were monitored using autosamplers. Water level in the cell was tracked using a staff gage in conjunction with time-lapse photography. Vegetation sampling was conducted in the spring and fall of each year to determine total plant cover and to assess species diversity. This paper focuses on efforts that are underway to study the variability in vegetation composition on the site using a high-resolution digital elevation model of the cell, coupled with hydrologic modeling. Variables of particular interest are the inundation frequency, duration, and depth at locations throughout the cell. The results presented here are preliminary, and have not been fully calibrated to site observations.