We are studying nitrogen cycling in marsh sediments of the Apalachicola National Estuarine Research Reserve (ANERR), Florida. TheANERR encompasses a productive and pristine ecosystem where the Apalachicola River reaches the Gulf of Mexico. Pristine beaches, beautiful scenery, abundant oysters, fish, manatees, dolphins, and migratory birds make the Apalachicola Bay a valuable resource and attractive recreation destination. Prior to reaching the ocean, the Apalachicola River forms a network of distributaries and flows through an extensive system of low-salinity marshes at the boundary between the River and the Apalachicola Bay.

Our work at the FSU Coastal and Marine Laboratory involves the study of long-term nitrogen loss via denitrification (nitrogen gas production by microorganisms) and nitrogen burial in ANERR marsh sediments. Controlled environment chambers at the FSUML are used to incubate sediment cores during rate measurements. Stable isotopes and mass spectrometry are used to trace the rates and pathways of nitrogen exchange between marshes and the surrounding estuary.  This research is being conducted with financial support from the NOAA Estuarine Reserves Division, graduate fellowship program for Tom Gihring, a graduate student in Dr. Kostka's laboratory.