Rate My Professor Suha Sanwar

The study characterized spatial variability in denitrification enzyme activity (DEA) and sediment properties (water content, pH, Eh, dissolved organic carbon, nitrate, ammonium, total carbon, total nitrogen, C:N ratio, dissolved Fe²⁺, Mn²⁺) across four wetlands in the Horizons Regional Council area. High-performing sites showed surface DEA >3000 μg N₂O-N kg⁻¹ DS h⁻¹, driven by high water content (>78%), nitrate (15.9-18.5 mg NO₃⁻-N kg⁻¹ DS), and organic matter, with sediment properties explaining 58-73% of DEA variation. Two-year hydrological monitoring at a low-performing site indicated streamflow-dominated inputs (83-87%) and average 23% annual nitrate removal, reaching 40.8% (2.78 kg NO₃⁻-N) in year two under dissipated flows and seasonal precipitation. Intact sediment column experiments achieved 50-96% removal of nitrate-rich runoff under anaerobic conditions, identifying optimal hydraulic residence times of 2 hours for 50% removal and 13 hours for near-complete reduction. These insights propose hydrological interventions to optimize wetland performance for nature-based nitrate mitigation under New Zealand's freshwater management policies. Suha Sanwar currently works as Resource Scientist in Lakes & Freshwater Ecology at Northland Regional Council.