What factors influence retention time in multifunctional constructed wetlands?
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Retention time in multifunctional constructed wetlands is influenced by several factors. The hydraulic retention time power parameter (n) of the modified first-order kinetic mathematical model (MFOKM) is inversely related to the hydraulic dispersion number (d) and the organic matter degradability . Tracer tests using fluorescein and deuterium oxide have shown that the tracer retention time (TRT) and nominal hydraulic retention time (nHRT) are nearly equal, indicating that these tracers can be successfully used to determine retention time . The impact of hydraulic loading rate (HLR) on retention efficiencies is negligible, as the large footprint of the system provides a high hydraulic retention time . The removal capacity and kinetics of pollutants in domestic wastewater are influenced by the number of plants in the constructed wetland, with the removal efficiency increasing with an increase in the number of plants . The presence of dense vegetation, such as common reed, can significantly prolong water retention times in the system through evapotranspiration .
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