INFLUENCE OF TEMPERATURE ON TREATMENT EFFICIENCY OF CONSTRUCTED WETLANDS

An existing free-water-surface constructed wetland system at the Aubur n University Poultry Science Unit was used to evaluate the effects of water temperature on the treatment of poultry lagoon effluent. Each we tland consisted of two cells in series. One series was planted with an approximate 10% fill of Sagittaria lancifolia A second series contain ed Phragmites australis and Scirpus spp. with an approximate 5% fill o f plants. A third series was unvegetated and acted as a control. Waste water samples were collected approximately every 12 days at the influe nt and effluent of each cell and analyzed for TKN, ammonia, nitrate, P ODS, GOD, total phosphorus, orthophosphorus, and potassium. Water temp erature was measured using thermographs placed at the midpoint of each cell with temperature readings being taken each hour from July 1995 u ntil June 1996. The percent removal of each wastewater pollutant from each series was compared to the average water temperature over the sam pling period (every 12 days) to determine what effect, if any, tempera ture had on treatment. For most cases, temperature was not found to si gnificantly affect treatment of poultry wastewater Treatment efficienc y (percent removal) was significantly correlated to temperature in one series for ammonia, one series for nitrate, one series for total phos phorus and one series for orthophosphorus. Mass removal was not correl ated to temperature in any of the cases studied.