title: Feasibility of Typha latifolia for high salinity effluent treatment in constructed wetlands for integration in resource management systems.
abstract: High salinity wastewaters have limited treatment options due to the occurrence of salt inhibition in conventional biological treatments. Using recirculating marine aquaculture effluents as a case study, this work explored the use of Constructed Wetlands as a treatment option for nutrient and salt loads reduction. Three different substrates were tested for nutrient adsorption, of which expanded clay performed better. This substrate adsorbed 0.31 mg kg(-1) of NH4(+)-N and 5.60 mg kg(-1) of PO4(3-)-P and 6.9 mg kg(-1) dissolved salts after 7 days of contact. Microcosms with Typha latifolia planted in expanded clay and irrigated with aquaculture wastewater (salinity 2.4%, 7 days hydraulic retention time, for 4 weeks), were able to remove 94% NH(4+)-N (inlet 0.25 +/- 0.13 mg L(-1)), 78% NO2(-)-N (inlet 0.78 +/- 0.62 mg L(-1)), 46% NO3(-)-N (inlet 18.83 +/- 8.93 mg L(-1)) whereas PO4(3-)-P was not detected (inlet 1.41 +/- 0.21 mg L(-1)). Maximum salinity reductions of 52% were observed. Despite some growth inhibition, plants remained viable, with 94% survival rate. Daily treatment dynamics studies revealed rapid PO4(3-)-P adsorption, unbalancing the N:P ratio and possibly affecting plant development. An integrated treatment approach, coupled with biomass valorization, is suggested to provide optimal resource management possibilities.
authors.forename: J M
authors.initials: JM
authors.lastname: Jesus
authors.forename: C S C
authors.initials: CS
authors.lastname: Calheiros
authors.forename: P M L
authors.initials: PM
authors.lastname: Castro
authors.forename: M T
authors.initials: MT
authors.lastname: Borges
mesh_terms: D017756:Aquaculture; D001673:Biodegradation, Environmental; D005240:Feasibility Studies; D009584:Nitrogen / Q000378:metabolism; D010758:Phosphorus / Q000378:metabolism; D054712:Salinity; D012965:Sodium Chloride / Q000378:metabolism; D032401:Typhaceae / Q000254:growth & development / Q000378:metabolism*; D014865:Waste Disposal, Fluid / Q000379:methods*; D062065:Wastewater / Q000032:analysis; D018508:Water Purification / Q000379:methods*; D053833:Wetlands
chemical_list: D009584:Nitrogen; D010758:Phosphorus; D012965:Sodium Chloride; D062065:Wastewater