North Central Washington

Remotely sensed fuel models

Remotely sensed fuel models: development of a fuel treatment strategy for Sinlahekin Wildlife Area based on future landscape scenarios

by
George Wooten and Dave Demyan, Pacific Northwest Division, Planetary Science Institute, Winthrop, Washington, & Hans Smith, Pacific Biodiversity Institute, Winthrop, Washington

Presented at the Northwest Scientific Association, 77th Annual Meeting, Central Washington University, Ellensburg, Washington, 24-27 March 2004

Abstract

Fuel treatment prescriptions, strategies and priorities were developed for the semi-arid Sinlahekin Wildlife Area of North-Central Washington, through a spatio-temporal model of fire behavior and vegetative succession. The goal of this project was to restore fire to the ecosystem while minimizing the loss of legacy trees and key habitat components. Fire behavior was modeled on topography, weather, and characteristics of surface and crown fuels. Ecological composition and structural models were classified using a combination of NASA's ASTER imagery, patch analysis, pattern recognition, and classification coincidence. This study improved existing maps of vegetation, fuels and canopy structure for the Sinlahekin Wildlife Area in North-Central Washington, as part of a plan to restore fire to the ecosystem. Models were classified using a combination of ASTER and orthophoto imagery, patch analysis, pattern recognition, and coincidence mapping of overlapping cells. The coincidence was compared among these and other existing classifications to derive an optimum approximation. Coincidence mapping of disparate data sources is an expedient tool for improving the confidence of classifications.

Keywords: fire, pattern recognition, coincidence

Authors: George Wooten1 (509-997-6010) Dave Demyan 1 (509-996-9826), Hans Smith2 (509-996-2490)

1 Pacific Northwest Division, Planetary Science Institute, Winthrop, Washington

2 Pacific Biodiversity Institute, Winthrop, Washington

Vegetation classification and canopy structure determination in the Sinlahekin Wildlife Area used map coincidence and pattern recognition

image

image 		Determination of canopy structure was based on patch pattern recognition of gray-scale orthophoto images.
image Patch thickness was the primary stand metric.
image Inter-patch distance was the primary metric for developing a map of canopy opening types.
image From the relationship of patch thickness to distance to openings, a map of canopy opening regimes was developed.
image The combination of types of openings and types of patches was made into a single map.
image The patch pattern factors were used to form a canopy cover classification (green shades) grouped here by regions of average cover and overlaid with the cells representing trees and shadows. 200 different combinations of canopy openings, aspect shading and canopy type were assigned different factors for canopy fraction within canopy shadows.
image Canopy Cover Coincidence. The final canopy cover map was classified in the same intervals as that of the existing Utah State canopy cover map and compared by counting the number of coincident cells.
image The use of map coincidence was used for other layers on the SWA by combining up to 4 layers representing a single feature and determining the percentage of coincidence. This map illustrates the coincidence of the NLCD shrub-steppe layer with a merged shrub-steppe layer from 4 different sources of shrub-steppe maps. The coincidence of the NLCD layer was 486,310 / 655,643 (74%) of the merged shrub-steppe layer.
image Through the use of refined data on canopy structure, cover type and fuel loadings, fire behavior can be modeled with dynamic fire simulators such as FARSITE and FlamMap (Finney, Mark A., S. Brittain, R. Seli. 2003. FlamMap 2 Beta Version 3.0.1. Rocky Mountain Res. Sta., US BLM, Systems for Environmental Management; Finney, Mark A. 1998. FARSITE users guide and technical documentation. USDA Forest Service GTR RMRS-RP-4). These models will be used to determine an effective restoration strategy. This image shows a simulated wildfire run (orange) made with FARSITE for the Sinlahekin Wildlife Area.