Related Experiment Video
Updated: Aug 10, 2026
08:24
Mesocosm-Scale Constructed Wetland Design for Wastewater Treatment
Published on: May 2, 2025
Nature-based solutions for nutrient and emerging contaminant reduction in a Mediterranean Ramsar wetland
Emilio Moreno1, María Gómez-Pozuelos2, Francisco Guerrero3,4
1Institute of Water Research, University of Granada, Ramón y Cajal, 4, 18071, Granada, Spain. emiliojml@ugr.es.
Environmental Geochemistry and Health
|August 8, 2026
Summary
Constructed wetlands effectively reduce nutrients and emerging contaminants in treated wastewater, especially during dry seasons. However, their performance is hydrologically dependent, with persistent contaminants and phosphorus requiring further management.
Area of Science:
- Environmental Science
- Ecotoxicology
- Wastewater Treatment
Background:
- Constructed wetlands are nature-based solutions for wastewater treatment.
- Mediterranean wetlands face hydrological variability impacting water quality.
- Understanding contaminant attenuation is crucial for protecting downstream ecosystems.
Purpose of the Study:
- Assess a semi-natural pond system's capacity to reduce nutrients and contaminants.
- Evaluate performance under contrasting water-circulation scenarios.
- Determine the influence of dry-season conditions on attenuation.
Main Methods:
- Conducted 26 sampling events over time.
- Analyzed nutrient and emerging contaminant concentrations.
- Estimated ecotoxicological risk using risk quotients.
Main Results:
- Total nitrogen reduced by 75% with regular flow.
- Emerging contaminants like trimethoprim and caffeine showed >70-90% removal.
- Persistent contaminants (carbamazepine, gemfibrozil) had limited reduction.
- Dry seasons enhanced attenuation due to lower flows and longer residence times.
- Ecotoxicological risk declined with regular flow but persisted under bypass.
Conclusions:
- The semi-natural pond system effectively mitigates nutrient and contaminant loads, but its capacity is hydrologically dependent.
- Elevated phosphorus and persistent contaminants indicate limitations of natural attenuation alone.
- Complementary management strategies are needed for long-term ecosystem protection.
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