SCALING RIPARIAN BUFFER CAPACITY OF NITROGEN: A SYNTHESIS OF NUMERICAL EXPERIMENTS

The multivariate nature of riparian buffer of nitrogen (N) makes it challenging to assess its effectiveness across the varying systems. Field measurements of N removal in riparian buffers are impeded by the difficulty of simultaneous measuring hydrogeological settings as well as groundwater flow pathways. The site-specific modeling approaches applied in the previous studies have limited success on extrapolate the results to varying environmental settings. In this study, I synthesize data from a numerical experiment using a 2D reactive transport model that accounts for variations of topography, hydrogeology, and soil physiochemical properties, etc. I used dimensional analysis to scale the N removal with respect to the environmental variables that are easily measurable. The prevailing controlling factors for the effectiveness of riparian buffer include: hydraulic gradient, hydraulic conductivity, organic carbon (OC) content, water table, and NO₃^- supply, etc. The results indicate the scaling relationship can be used to quantify riparian N buffering capacity in a large scale (i.e. watershed scale) with a variety of environmental settings.