Wetlands as a means to improve water quality
Mechanisms of improving water quality n trap sediment n sequester pollutants n remove phosphorous n remove/modify excess nitrogenous waste –how?
Sources of pollution that can affect water quality n Agriculture - fertilizers n Aquaculture - animal waste/feed n Livestock - animal waste/feed n Human waste -water treatment plants n Industry
Current Research n Natural Systems F modelling (Park et al. 2003) n Constructed systems
Constructed Wetland experiments n Kinds of plants u emergent (watercress), submergent (waterfern), free-floating (pondweed) ( Redding et al. 1997) n Direction of flow (Farahbakhshazad and Morrison et al. 1997) n Concentration of waste n Economics (Mississippi State University)
Future Research n Municipal waste treatment? n Different emergent plants? n Improve economic viability?
References n Cossu, R., Haarstad, K., Lavagnolo, M.C., and Littarru, P Removal of municipal solid waste COD and NH 4 –N by phyto-reduction: A laboratory-scale comparison of terrestrial and aquatic species at different organic loads. Ecological Engineering. 16:4 pgs n Costa-Pierce, B.A Prelimenary investigation of an integrated aquaculture- wetland ecosystem using tertiary-treated municipal wastewater in Los Angeles County, California. Ecological Engineering. 10:4 pgs n Farahbakhshazad, N. and Morrison, G.M Ammonia Removal Process for Urine in an Upflow Macrophyte System. Environ. Sci. Technol. 31 pgs n Park, S.S., Na, Y., and Uchrin, C An oxygen equivalent model for water quality dynamics in a macrophyte dominated river. Ecological Modelling. 168:1-2 pgs n Redding, T., Todd, S., and Midlen, A The treatment of aquaculture wastewaters-A botanical approach. Journal of Environmental Management. 50 pgs n Mississippi State University: