A detailed ecosystem model of phosphorus dynamics in created riparian wetlands

Evaluating the use of recycled coal combustion products in constructed wetlands: an ecologic-economic modeling approach

“…Wang and Mitsch (2000) verified that TP inflow concentration and phosphorus sedimentation coefficient (sed k in our model) were the most sensitive parameters explaining TP retention in a dynamic phosphorus model of created wetlands. Therefore, we carried out sensitivity analysis of TP inflow concentration and the sedimentation coefficient (sed k) on corresponding changes of TP retention (%) in our model runs with the LCW.…”

“…Calibration was carried out by adjusting selected parameters in the model to obtain a best fit between model estimations and field data from ORW 1 for TP retention. A stepwise method (Mitsch and Reeder, 1991;and Wang and Mitsch, 2000) was used in this process by first calibrating the hydrology submodel, then macrophyte submodel, phosphorus submodel, and finally economic model. At each step, values of parameters determined during the previous step were not allowed to change from previously calibrated values.…”

“…Macrophyte production included only aboveground biomass in this model. A solar efficiency of 2.5% (e.g., Wang and Mitsch, 2000) was estimated and applied to simulate net primary productivity of macrophytes in the submodel. An estimated 20% reduction in plant growth was applied as a toxicity effect with a FGD material ) only during the first growing season (13-38th week) of the wetland model simulated with a FGD liner.…”

“…The standing stock serves as a set of ʻliving weirsʼ that reduce the velocity of the inflow, thereby enhancing physical sedimentation of phosphorus. Physical sedimentation is the major pathway of phosphorus retention through wetlands (Wang and Mitsch, 2000). The effect of temperature on detritus decay was assumed to follow an exponential function based on Brown and Barnwell (1987).…”

“…Dynamic models of phosphorus retention in wetlands have been studied extensively (Kadlec and Hammer, 1988;Mitsch and Reeder, 1991;Kadlec, 1997;Richardson et al, 1997;and Wang and Mitsch, 2000). Some studies have also attempted to interlink ecology model and economic analysis (Baker et al, 1991;Breaux et al, 1995;Grant and Thompson, 1997;Robles-Diaz-de-Leon and Vava-Tudela, 1998;van der Belt et al, 1998;Cardoch et al, 2000).…”