Rocky Mountain Research Station Publications

RMRS Online Publication - Journal Articles, External Publications, and Special Reports
Spatial and temporal corroboration of a fire-scar-based fire history in a frequently burned ponderosa pine forest


Farris, Calvin, A.; Baisan, Christopher H.; Falk, Donald A.; Yool, Stephen R.; Swetnam, Thomas W. 2010. Spatial and temporal corroboration of a fire-scar-based fire history in a frequently burned ponderosa pine forest. Ecological Applications. 20(6): 1598-1614.

Fire scars are used widely to reconstruct historical fire regime parameters in forests around the world. Because fire scars provide incomplete records of past fire occurrence at discrete points in space, inferences must be made to reconstruct fire frequency and extent across landscapes using spatial networks of fire-scar samples. Assessing the relative accuracy of fire-scar fire history reconstructions has been hampered due to a lack of empirical comparisons with independent fire history data sources. We carried out such a comparison in a 2780-ha ponderosa pine forest on Mica Mountain in southern Arizona (USA) for the time period 1937-2000. Using documentary records of fire perimeter maps and ignition locations, we compared reconstructions of key spatial and temporal fire regime parameters developed from documentary fire maps and independently collected fire-scar data (n ? 60 plots). We found that fire-scar data provided spatially representative and complete inventories of all major fire years (.100 ha) in the study area but failed to detect most small fires. There was a strong linear relationship between the percentage of samples recording fire scars in a given year (i.e., fire-scar synchrony) and total area burned for that year (y=0.0003x+0.0087, r2=0.96). There was also strong spatial coherence between cumulative fire frequency maps interpolated from fire-scar data and ground-mapped fire perimeters. Widely reported fire frequency summary statistics varied little between fire history data sets: fire-scar natural fire rotations (NFR) differed by ,3 yr from documentary records (29.6 yr); mean fire return intervals (MFI) for large-fire years (i.e., 25% of study area burned) were identical between data sets (25.5 yr); fire-scar MFIs for all fire years differed by 1.2 yr from documentary records. The known seasonal timing of past fires based on documentary records was furthermore reconstructed accurately by observing intra-annual ring position of fire scars and using knowledge of treering growth phenology in the Southwest. Our results demonstrate clearly that representative landscape-scale fire histories can be reconstructed accurately from spatially distributed firescar samples.

Keywords: empirical corroboration, fire history, fire-scar data, landscape scale, National Park Service Fire Atlas maps, ponderosa pine, Saguaro National Park, southern Arizona, USA, Thiessen polygons


About PDFs: For best results, do not open the PDF in your Web browser. Right-click on the PDF link to download the PDF file directly to your computer. Click here for more PDF help.


Download Article
http://www.fs.fed.us/rm/pubs_other/rmrs_2010_farris_c001.pdf

PDF File Size: 565 K


Title: RMRS Other Publications: Spatial and temporal corroboration of a fire-scar-based fire history in a frequently burned ponderosa pine forest
Electronic Publish Date: March 18, 2011
Last Update:
March 18, 2011

RMRS Publications | Order a publication | Contact Us