WWETAC Projects

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

Principal Investigator: Reynolds, Keith M., USDA Forest Service, Pacific Northwest Research Station (PNWRS), Corvallis OR

kreynolds[at]fs.fed.us
                                               
Collaborators: Paul F. Hessburg, PNWRS; Bob Meurisse, PBS Engineering and Environmental; Dick Miller, private soils consultant

Key Issues/Problems Addressed:

Rehabilitation and timber salvage activities after wildfires require rapid planning and informed decision making.

Identifying areas at high risk for erosion and soil productivity losses will help guide and prioritize post-wildfire management activities.

Setting and Approach:

The Ecosystem Management Decision Support (EMDS) system was used to evaluate risks to soils associated with wildfire and unmitigated use of ground-based logging equipment on the Okanogan-Wenatchee National Forest in central Washington.  EMDS is an extension to ArcMap that integrates logic-based modeling, which outlines how a project is understood to produce particular results, into the geographic information system (GIS) environment.

Soil and related data were collected from standard National Cooperative Soil Surveys for the Okanogan East soil survey area, encompassing 6,889 soil polygons and 69 438 ha. Due to the fact that adequate GIS data is not always available, a stand-alone application was developed for field-going computers.

Key Findings:

  • In the Okanogan East soil survey area, 36 percent of soils were classified as sensitive to impacts from severe wildfire, and 46 percent of soils were classified as sensitive to unmitigated use of logging equipment. There is also a high degree of correspondence between the map of units sensitive to wildfire and the map of units sensitive to heavy equipment.
  • Both the GIS-based application and the field-going version are adaptable to new geographic areas.
  • Both applications can be extended to include additional relevant topics, such as potential threats associated with invasive species.

Impacts/Applications:

A knowledge-based approach is presented for interpreting risks to soil erosion and productivity from moderate to severe wildfire and ground-based logging equipment.  The risk-rating scheme can aid in prescribing, planning, and scheduling timber harvest and forest restoration activities. Ratings identify and locate sensitive areas where mitigation or restoration efforts could be focused to maximize benefits and minimize costs and ecological consequences.

Publication:

Reynolds, K.M., P.F. Hessburg, R.E. Miller, and R.T. Meurisse. 2011. Predicting risk of soil degradation associated with wildfire and ground-based logging. Gen. Tech. Rep. PNW-GTR-880. Portland, OR: USDA Forest Service, Pacific Northwest Research Station. (PDF, 1.06 MB)

WWETAC Project ID:  FY06TS9