Denitrification Performance and Nitrogen Removal Pathways in Constructed Wetlands Treating Simulated Mariculture Wastewater
DOI:
https://doi.org/10.15377/2410-3624.2026.13.4Keywords:
Salinity stress, Denitrification, Constructed wetland, Mariculture wastewater, Nitrogen removal efficiency.Abstract
To address the problem of eutrophication in nearshore waters caused by nitrogen pollution from marine aquaculture effluent and to investigate the patterns of denitrification in constructed wetlands under simulated marine aquaculture conditions, this study constructed a vertical subsurface flow constructed wetland system. Using simulated marine aquaculture effluent as the treatment substrate, the study systematically examined the effects of hydraulic retention time (HRT), salinity, and wetland substrate type on denitrification efficiency. The experimental results indicate that the constructed wetland demonstrated excellent removal efficiency for NH+4-N, NO-3-N, and NO-2-N. The optimal operating parameter combination was an HRT of 12 h, C/N ratio of 8, and a salinity of 25‰, achieving an NO-3-N removal rate of 82.15% NH+4-N removal reached 77.5%, and NO-2-N accumulation was controlled below 0.35 mg/L. This study elucidated the denitrification patterns in constructed wetlands treating simulated seawater aquaculture effluent, optimized operational parameters, and provided a theoretical basis and technical support for the ecological treatment of seawater aquaculture effluent, aligning with the research needs in the field of environmental engineering for efficient, low-cost pollution control technologies.
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