Cui, L.; Li, W.; Zhang, Y.; Wei, J.; Lei, Y.; Zhang, M.; Pan, X.; Zhao, X.; Li, K.; Ma, W. Nitrogen Removal in a Horizontal Subsurface Flow Constructed Wetland Estimated Using the First-Order Kinetic Model. Water2016, 8, 514.
Cui, L.; Li, W.; Zhang, Y.; Wei, J.; Lei, Y.; Zhang, M.; Pan, X.; Zhao, X.; Li, K.; Ma, W. Nitrogen Removal in a Horizontal Subsurface Flow Constructed Wetland Estimated Using the First-Order Kinetic Model. Water 2016, 8, 514.
Cui, L.; Li, W.; Zhang, Y.; Wei, J.; Lei, Y.; Zhang, M.; Pan, X.; Zhao, X.; Li, K.; Ma, W. Nitrogen Removal in a Horizontal Subsurface Flow Constructed Wetland Estimated Using the First-Order Kinetic Model. Water2016, 8, 514.
Cui, L.; Li, W.; Zhang, Y.; Wei, J.; Lei, Y.; Zhang, M.; Pan, X.; Zhao, X.; Li, K.; Ma, W. Nitrogen Removal in a Horizontal Subsurface Flow Constructed Wetland Estimated Using the First-Order Kinetic Model. Water 2016, 8, 514.
Abstract
We monitored the water quality and hydrological conditions of a horizontal subsurface constructed wetland (HSSF-CW) in Beijing, China, for 2 years. We simulated the area rate constant and the temperature coefficient with the first-order kinetic model. We examined the relationships between the nitrogen (N) removal rate, N load, seasonal variations in the N removal rate, and environmental factors, such as the area rate constant, temperature, and dissolved oxygen (DO). The effluent ammonia (NH4+-N) and nitrate (NO3−-N) concentrations were significantly lower than the influent concentrations (p<0.01, n=38). The NO3−-N load was significantly correlated with the removal rate (R2=0.9566, p<0.01), but the NH4+-N load was not correlated with the removal rate (R2=0.0187, p>0.01). The area rate constants of NO3−-N and NH4+-N at 20 °C were 27.01±26.49 and 16.63±10.58 m∙yr−1, respectively. The temperature coefficients for NO3−-N and NH4+-N were estimated at 1.0042 and 0.9604, respectively. The area rate constants for NO3−-N and NH4+-N were not correlated with temperature (p>0.01). The NO3−-N area rate constant was correlated with the corresponding load (R2=0.9625, p<0.01). The NH4+-N area rate was correlated with DO (R2=0.6922, p<0.01), suggesting that the factors that influenced the N removal rate in this wetland met Liebig's law of the minimum.
Keywords
horizontal subsurface flow wetland; N removal; first-order kinetics; model
Subject
Biology and Life Sciences, Ecology, Evolution, Behavior and Systematics
Copyright:
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