Quantitative estimates of denitrification are needed in designing artificial wetlands to optimize nitrate (NOj-) removal. Acetylene blockage and ~SN-tracer methods were employed to quantify denitriflcation in constructed wetlands receiving agricultural tile drainage, using plastic tubes to enclose in situ mesocosms. Estimates were also made through NO;disappearance from mesocosm water columns. ...

The Long Island Sound (LIS) estuary is affected by summer hypoxia as a result of high nitrogen loads from New York and Connecticut watersheds. In order to mitigate hypoxia, managers have established a goal of reducing the nitrogen load from nonpoint sources by 10%. One strategy to reduce N loads from nonpoint sources is the use of constructed wetlands, which provide an ecosystem service by remo...

The large land area requirement of constructed wetlands (CWs) is a major limitation of its application especially in densely populated and mountainous areas. This review paper provides insights on different strategies applied for the reduction of land area including stack design and intensification of CWs with different aeration methods. The impacts of different aeration methods on the performa...

Modeling water flow in a VFCW is a prerequisite to model wastewater treatment using process based filtering models. As for soils, when the vertical structure varies in different material types, it has a significant impact on water flow passing through it. The heterogeneous filtering material is composed of a mix of mineral porous material, and organic matter which makes its hydraulic characteri...

Sedimentation is thought to be one of the mechanisms of microbial reduction from wetlands used for wastewater treatment. This study compared the occurrence and survival of enteric indicator microorganisms and pathogens in the water column and sediments of two constructed surface flow wetlands in Arizona. On a volume/wet weight basis the concentration of fecal coliforms and coliphage in the wate...

Constructed wetland treatment of swine wastewater probably involves substantial denitrification. Our objective was to assess denitrification and denitrification enzyme activity (DEA) in such wetlands in relation to plant communities, N loading, carbon or nitrogen limitations, and water depth. Two wetland cells each 3.6 m wide and 33.5 m long were connected in series. One set of cells was plante...

Innovative wastewater treatment systems are needed for removing nutrients, noxious odors, dissolved organic matter, and pathogens from high strength agricultural and processing wastewater. A novel reciprocating subsurface-flow constructed wetland, consisting of four cells totaling 3570 m (1.5 m deep), has been treating anaerobic lagoon wastewater from a commercial-scale confined swine feeding o...