USING CAPACITANCE MOISTURE PROBES TO INVESTIGATE THE EFFECT OF CHANGES IN WATER TABLE ELEVATION ON BIOGENIC GAS DYNAMICS IN PEAT SOILS FROM THE FLORIDA EVERGLADES

Peatlands are known to act as carbon sinks while representing major sources of biogenic gases such as methane (CH₄) and carbon dioxide (CO₂), two potent greenhouse gases. The subtropical climate of the Florida Everglades with overall warm temperatures (when compared to boreal systems) have resulted in conditions conducive to biogenic gas releases throughout the entire year. Such releases are however not well understood and the temporal distribution and dynamics of biogenic gas release from peat soils of the Florida Everglades is uncertain. The objective of this work is to test the use of capacitance moisture probes for measuring changes in gas content within peat matrixes at a high temporal resolution (i.e. minute scales) and to better understand the effects that changes in water table may impose on biogenic gas dynamics in several peat monoliths from the Florida Everglades at the laboratory scale. The capacitance moisture probe measurements estimate changes in moisture content over time within the peat matrix and are coupled with gas traps and time-lapse cameras in order to compare gas dynamics with direct gas releases. Peat matrix deformation, as a result of increases and decreases in water table elevation, will also monitored using surface deformation probes. This work has implications for better understanding patterns of gas build-up and release from peat soils in the Everglades in response to changes in water table elevation and therefore may provide information on how climate change may affect gas dynamics.