Project Funding: 2009 - 2013

NRA: 2008 NASA: Terrestrial Ecology   

Funded by NASA

Abstract:
One of the major uncertainties in more accurately assessing the role of boreal fires on atmospheric trace gas concentrations is our poor understanding of how fire influences more poorly drained ecosystems such as peatlands. Boreal peatlands store tremendous reservoirs of soil carbon that are likely to become increasingly vulnerable to fire as climate change lowers water tables and exposes C-rich peat to burning. Despite previous conceptions that wildland fires had relatively little impact on peatlands, recent research has shown that fire activity in Alberta, Canada can play an important role in peatland carbon cycling. However, there continues to be uncertainty as to whether peatlands across the North American boreal region are vulnerable to burning, and whether expected increases in surface soil moisture deficits under future climate change scenarios will increase the frequency and/or severity of peat fires. Increasing fire activity in peatlands could cause these ecosystems to become net sources of C to the atmosphere, which is likely to have large influences on atmospheric carbon concentrations through positive feedbacks that enhance climate warming. The overall goal of the proposed research project is to develop an understanding of how interactions between climate, surface hydrology and the fire regime impact ecosystem processes and carbon cycling in boreal peatlands. To address this overall goal, we will integrate observations from field studies and satellite imagery with carbon cycle models to address the following four objectives: 1. Assess the spatial and temporal controls on peatland burned area. 2. Determine how interactions between climate, vegetation, and surface moisture dynamics control variations in fire severity and vulnerability to deep peat burning. 3. Assess changes in post-fire hydrology and vegetation in peatlands. 4. Use the enhanced understanding of the interaction of climatic and hydrologic factors that control the vulnerability of these ecosystems to burning to improve C cycling predictions. Our tasks include using remote sensing to 1) map and classify peatlands in each study region, 2) characterize seasonal and inter-annual variations in the moisture content of surface peat (fuel) layers, 3) map the extent and seasonal timing of fires in peatlands, and 4) discriminate different levels of fuel consumption severity in peat fires. Field-based studies will be coordinated with research being carried out by Canadian scientists to collect vegetation and hydrology data to validate peatland distribution maps within Alberta, water table depths, and peat moisture content data, and characterize variations in depth of burning and carbon consumption during peatland fires to use in fire emissions modeling. The proposed research project will reduce uncertainties of the role of northern high latitude ecosystems in the global carbon cycle and will improve carbon emission estimates from boreal fires.

Publications:

Bourgeau-Chavez, L. L., Endres, S., Powell, R., Battaglia, M. J., Benscoter, B., Turetsky, M., Kasischke, E. S., Banda, E. 2017. Mapping boreal peatland ecosystem types from multitemporal radar and optical satellite imagery. Canadian Journal of Forest Research. 47(4), 545-559. DOI: 10.1139/cjfr-2016-0192

Turetsky, M. R., Benscoter, B., Page, S., Rein, G., van der Werf, G. R., Watts, A. 2014. Global vulnerability of peatlands to fire and carbon loss. Nature Geoscience. 8(1), 11-14. DOI: 10.1038/NGEO2325

Bourgeau-Chavez, L. L., Leblon, B., Charbonneau, F., Buckley, J. R. 2013. Assessment of polarimetric SAR data for discrimination between wet versus dry soil moisture conditions. International Journal of Remote Sensing. 34(16), 5709-5730. DOI: 10.1080/01431161.2013.796096

Bourgeau-Chavez, L. L., Leblon, B., Charbonneau, F., Buckley, J. R. 2013. Evaluation of polarimetric Radarsat-2 SAR data for development of soil moisture retrieval algorithms over a chronosequence of black spruce boreal forests. Remote Sensing of Environment. 132, 71-85. DOI: 10.1016/j.rse.2013.01.006

Bourgeau-Chavez, L. L., Leblon, B., Charbonneau, F., Buckley, J. R. 2013. Assessment of polarimetric SAR data for discrimination between wet versus dry soil moisture conditions. International Journal of Remote Sensing. 34(16), 5709-5730. DOI: 10.1080/01431161.2013.796096

Leblon, Brigitte, and Laura Bourgeau-Chavez. 'Wildfire.' Encyclopedia of Natural Hazards 2013: 1102-1107. https://www.library.yorku.ca/find/Record/3181616/TOC, ISBN: 9781402043994 (electronic bk.) 1402043996 (electronic bk.) ISSN: 1388-4360

Grosse, G., Harden, J., Turetsky, M., McGuire, A. D., Camill, P., Tarnocai, C., Frolking, S., Schuur, E. A. G., Jorgenson, T., Marchenko, S., Romanovsky, V., Wickland, K. P., French, N., Waldrop, M., Bourgeau-Chavez, L., Striegl, R. G. 2011. Vulnerability of high-latitude soil organic carbon in North America to disturbance. Journal of Geophysical Research. 116. DOI: 10.1029/2010JG001507

2015 NASA Carbon Cycle & Ecosystems Joint Science Workshop Poster(s)

• Vulnerability of North American Boreal Peatlands to Interactions between Climate, Hydrology, and Wildland Fires   --   (Laura L. Bourgeau-Chavez, Eric S. Kasischke, Merritt Turetsky, William de Groot, Liza Jenkins, Sarah Endres, Michael Billmire, Brian Brian)   [abstract]   [poster]
• Continuous wavelet analysis for spectroscopic determination of sub-surface moisture and water-table height in northern peatland ecosystems   --   (Michael Falkowski, Asim Banskota, Evan S Kane, Alistair Matthew Stuart Smith, Laura Louise Bourgeau-Chavez, Nancy HF French)   [abstract]

2013 NASA Terrestrial Ecology Science Team Meeting Poster(s)

• Vulnerability of North American Boreal Peatlands to Interactions between Climate, Hydrology, and Wildland Fires   --   (Laura Louise Bourgeau-Chavez, Eric S. Kasischke, Merritt R. Turetsky, Brian Benscoter, Elizabeth Banda, Erik Boren, Liza Jenkins, Naomi Hamermesh)   [abstract]

2011 NASA Carbon Cycle & Ecosystems Joint Science Workshop Poster(s)

• Assessment of polarimetric SAR data for fuel moisture estimation: Analysis of wet versus dry conditions   --   (Laura Louise Bourgeau-Chavez)   [abstract]   [poster]
• Monitoring soil moisture with SAR for assessment of peatland vulnerability to wildfire   --   (Laura Louise Bourgeau-Chavez, Eric S. Kasischke, Merritt R. Turetsky, Anne Santa Maria, Elizabeth Banda, Gordon Garwood, Eric Keefauver, Liza Jenkins, William Schultz)   [abstract]   [poster]

2010 NASA Terrestrial Ecology Science Team Meeting Poster(s)

• Mapping Boreal Peatlands for Assessment of Vulnerability to Wildfire   --   (Laura Louise Bourgeau-Chavez, Richard B Powell, Brian Benscoter, Merritt Turetsky, Erik S. Kasischke)   [abstract]   [poster]

More details may be found in the following project profile(s):

• NASA Terrestrial Ecology (TE) Project Profile
• North American Carbon Program (NACP) Project Profile