title: Design and monitoring of horizontal subsurface-flow constructed wetlands for treating nursery leachates.
abstract: Nursery leachates usually contain high concentrations of nitrates, phosphorus and potassium, so discharging them into the environment often causes pollution. Single-stage or two-stage horizontal subsurface flow constructed wetlands (HSSCW) filled with different substrates were designed to evaluate the effect and evolution over time of the removal of nitrogen and other nutrients contained in nursery leachates. The addition of sodium acetate to achieve a C:NO(3)(-)-N ratio of 3:1 was sufficient to reach complete denitrification in all HSSCW. The removal rate of nitrate was high throughout the operation period (over 98%). Nevertheless, the removal rate of ammonium decreased about halfway through the operation. Removal of the COD was enhanced by the use of two-stage HSSCW. In general, the substrates and the number of stages of the wetlands did not affect the removal of nitrogen, total phosphorus and potassium.
authors.affiliation: Unit of Biosystems Engineering and Agronomy, IRTA, Ctra. Cabrils s/n, 08348 Cabrils, Barcelona, Spain. lola.narvaez@irta.es
authors.forename: Lola
authors.initials: L
authors.lastname: Narváez
authors.forename: Conrad
authors.initials: C
authors.lastname: Cunill
authors.forename: Rafaela
authors.initials: R
authors.lastname: Cáceres
authors.forename: Oriol
authors.initials: O
authors.lastname: Marfà
mesh_terms: D000383:Agriculture; D001673:Biodegradation, Environmental; D057919:Biological Oxygen Demand Analysis; D004553:Electric Conductivity; D006863:Hydrogen-Ion Concentration; D008956:Models, Chemical; D009584:Nitrogen / Q000302:isolation & purification; D010865:Pilot Projects; D012212:Rheology; D013997:Time Factors; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
chemical_list: D014874:Water Pollutants, Chemical; D009584:Nitrogen