Resumen de Nitrogen removal in Myriophyllum aquaticum wetland microcosms for swine wastewater treatment: 15 N-labelled nitrogen mass balance analysis.
Shunan Zhang, Feng Liu, Runlin Xiao, Yang He, Jinshui Wu
Ecological treatments are effective for treating agricultural wastewater. In this study, wetland microcosms vegetated with Myriophyllum aquaticum were designed for nitrogen (N) removal from two strengths of swine wastewater, and 15 N-labelled ammonium (NH4+ -N) was added to evaluate the dominant NH4+ -N removal pathway.; Results: The results showed that 98.8% of NH4+ -N and 88.3% of TN (TN: 248.6 mg L-1 ) were removed from low-strength swine wastewater (SW1) after an incubation of 21 days, with corresponding values for high-strength swine wastewater (SW2) being 99.2% of NH4+ -N and 87.8% of TN (TN: 494.9 mg L-1 ). Plant uptake and soil adsorption respectively accounted for 24.0% and 15.6% of the added 15 N. Meanwhile, above-ground tissues of M. aquaticum had significantly higher biomass and TN content than below-ground (P < 0.05). 15 N mass balance analysis indicated that gas losses contributed 52.0% to the added 15 N, but the N2 O flux constituted only 7.5% of total gas losses. The dynamics of NO3- -N and N2 O flux revealed that strong nitrification and denitrification occurred in M. aquaticum microcosms, which was a dominant N removal pathway.; Conclusion: These findings demonstrated that M. aquaticum could feasibly be used to construct wetlands for high N-loaded animal wastewater treatment. © 2016 Society of Chemical Industry.; © 2016 Society of Chemical Industry.
