Landscape-level habitat supply modelling to develop and evaluate management practices that maintain diverse forest values in a dry forest ecosystem in southern British Columbia

摘要

We used the TELSA forest landscape model to examine the long-term consequences of applying different forest management scenarios on indicators of wildlife habitat, understory productivity, crown fuel hazard, timber yield and treatment costs. The study area was a dry forest dominated landscape of approximately 100000ha near Kamloops, BC where fire safe communities, timber harvest and the maintenance of biodiversity are important social expectations. Conventional partial cut harvesting treatments maintained timber yields but strongly reduced the area supporting high snag densities, provided low levels of understory productivity and diminished the area that was undisturbed for extended periods. In contrast, the application of extensive fuel management treatments designed to prevent extreme fire behaviour diminished timber flow, but, as with partial cut harvesting, reduced the area with high snag densities and extended periods without disturbance. The application and maintenance of extensive fuel management treatments was also the most costly treatment. Alternatives, such as strategically placed fuel management treatments in critical zones around communities or areas with high investments, diminished costs and somewhat mitigated the reduction in snag densities. More complex land use zoning approaches that incorporate specific practices (e.g. protected areas) to maintain high quality wildlife habitat, and treatments that promote productive understories, appear to hold promise if multiple forest values and objectives are to be maintained in the long-term. We conclude that forest landscape modelling can and should be used to assess the consequences of current or new management initiatives prior to their application to ensure expectations regarding costs and achievement of objectives are realistic.