Evaluating soil risks associated with severe wildfire and ground-based logging

Rehabilitation and timber-salvage activities after wildfire require rapid planning and rational decisions. Identifying areas with high risk for erosion and soil productivity losses is important. Moreover, allocation of corrective and mitigative efforts must be rational and prioritized. Our logic-based analysis of forested soil polygons on the Okanogan-Wenatchee National Forest was designed and implemented with the Ecosystem Management Decision Support (EMDS) system to evaluate risks to soil properties and productivity associated with moderate to severe wildfire and unmitigated use of ground-based logging equipment. Soil and related data are from standard National Cooperative Soil Surveys. We present results from one national forest management unit, encompassing 6,889 soil polygons and 69 438 ha. In the example area, 36.1 percent and 46.0 percent of the area were classified as sensitive to impacts from severe wildfire and unmitigated use of logging equipment, respectively, and there was a high degree of correspondence between the map of units sensitive to wildfire and the map of units sensitive to heavy equipment. We discuss options for extending the current model and considerations for validating key model components.