TEMPERATURE-DEPENDENT EFFECTS OF ROAD DEICING SALT ON CHIRONOMID LARVAE

Road salt, a common pollutant in regions with snowy winters, enters roadside wetlands when temperatures are low and organisms are physiologically inactive and remains until flushed by snowmelt or rainfall. Flushing might not occur until spring temperatures rise and organisms are physiologically active. Thus, effects of road salt on aquatic organisms must be studied within the context of temperature. We monitored temperature and conductivity at the sediment-water interface from January to May 2004-2006 in two constructed wetlands in Erie, Pennsylvania. Runoff caused peaks in conductivity (up to similar to 30 mS/cm) followed by exponential declines. Conductivity remained >4 mS/cm during winter and returned to <1 mS/cm in late spring >temperature >10 degrees C). Overspray caused lower peaks (