Minorities in the Aquatic Sciences

Determining Sources of Phosphorous Concentration Spikes in Taylor River

This study is being conducted in Taylor River in the southern mangrove ecotone region of Taylor Slough in the Florida Everglades. Taylor River is located in this ecotone region between two FCE-LTER water quality monitoring stations. In this study we hope to determine the source of phosphorous concentration spikes which occur during periods of decreased freshwater flow and longer water residence times. A 3 km pond vs. creek transect was formed from TS/Ph 6, the northern end member and TS/Ph 7 which is located at the mouth of Taylor River, which feeds into Little Madeira Bay. A total of 13 sample sites, 6 ponds and 7 creeks, will be analyzed for water quality. In addition, floc cores will be taken from each of the 6 ponds and analyzed for C:N:P ratios.

This system is characterized by a series of interconnected creeks and ponds that make up the larger Taylor River. We have observed relationships between salinity and increased phosphorus concentrations in the long-term data collected at these two sites; these findings appear to be supported by the scientific literature. During the wet season months from June to November, there is a distinct freshwater input on the mangrove estuary from the north. This freshwater pulse essentially “flushes” most of the river and lowers salinity to less than 1 ppt. However, during dry months from December to May, water residence times increase dramatically and salinity can increase to over 35 ppt.. We hypothesize that the P concentration spikes observed during these months is a result of benthic process and longer water residence times in the river rather than P input from Florida Bay.