Multi-scale characterization of biogenic gas dynamics in peat soils using hydrogeophysical methods: implications for biogenic gas distribution and carbon fluxes in the Everglades Xavier Comas 1 , Lee Slater 2 , Andrew Reeve 3 , Paul Glaser 4 , Jay Nolan 2 , Andrew Parsekian 2 and Anastasija Cabolova 1 1 Department of Geosciences, Florida Atlantic University, Boca Raton, FL 2 Department of Earth & Environmental Sciences, Rutgers University, Newark, NJ 3 Department of Earth Sciences, University of Maine, Orono, ME 4 Department of Geology and Geophysics, University of Minnesota, Minneapolis, MN
22
Embed
Multi-scale characterization of biogenic gas dynamics in ...
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Transcript
Multi-scale characterization of biogenic gas dynamics in peat soils using hydrogeophysicalmethods: implications for biogenic gas distribution and carbon fluxes in the Everglades
Xavier Comas1, Lee Slater2, Andrew Reeve3, Paul Glaser4, Jay Nolan2, Andrew Parsekian2 and Anastasija Cabolova1
1 Department of Geosciences, Florida Atlantic University, Boca Raton, FL2 Department of Earth & Environmental Sciences, Rutgers University, Newark, NJ3 Department of Earth Sciences, University of Maine, Orono, ME4 Department of Geology and Geophysics, University of Minnesota, Minneapolis, MN
Outline
I. Introduction Peatlands and gas ebullition
II. The ground penetrating radar (GPR) method
III. Applications in peatlands Spatial variability in
biogenic gas distribution Temporal variability in gas
fluxes both at the field and laboratory scale
IV. Future directions
Caribou Bog, Maine
WCA-1, Florida
I. Introduction
Caribou Bog, Maine
Represent about 35-50% of total terrestrial C yet only cover 3% of Earth’s land
Considered net source of CH4 (net sink of CO2)
Biogenic methane production –methanogenesis
Uncertainties in spatial and temporal distribution
Uncertain response to global warming and/or restoration efforts (i.e. change in water table elevation, water chemistry, etc)
Peatlands
Open pools in a northern peatland in Maine (central unit, Caribou Bog)
Current models for gas accumulation in peatlands
Deep vs shallow accumulations Carbon Cycling in Northern Peatlands; AGU Geophysical Monograph Series, Volume 184, 299 pp.
Biogenic gas release from peatlands
Mechanisms: Diffusion Transport through
vascular plants Ebullition
Controls: Soil T Chemical composition
(organic matter quality)
Whalen, 2005
Plant community structure Water table elevation (redox boundary) Atmospheric Pressure
Ebullition fluxes from peatlands
Source: Waddington, 2007, Fall American Geophysical Union Meeting
Spatiotemporal variation?
Episodic ebullition events can release large volumes of gas over a short time scale (35 g CH4/m2 in a matter of minutes or hours (Glaser et al. 2004)