| Abstract/Description or Keywords |
The mountain pine beetle (Dendroctonus ponderosae Hopkins) epidemic is changing British Columbia’s forests and watersheds at the landscape scale. Watersheds with pine-leading stands may experience changes in their water balance once the pines die. Forestry stakeholders in the Vanderhoof Forest District have reported an increase in groundwater storage. They report a replacement of summer ground (dry, firm soil) with winter ground (wetter, less firm soil), upon which operation of forestry equipment is difficult or impossible before freeze-up. This project was developed to identify a set of risk indicators to predict the risk of summer-ground loss at the watershed level within the Vanderhoof Forest District and others. Risk indicators were selected from available GIS information, aerial photographs, and local knowledge. To make these indicators operationally applicable in forest planning, general information such as watershed aspect, slope, soil type, and others were used. Indicators were selected during an iterative process that included model refinement, prediction, and field verification over a two-year period and a post-hoc assessment of field information to select the indicators that explain most data variability. The most effective indicators for predicting the risk of wet-ground areas at the watershed level were found to be lodgepole pine content, understorey, drainage density, sensitive soils, and the topographic index, all of whose values are available from provincial databases. Mountain pine beetle; soil hydrology; risk indicators; risk assessment; water balance |
