Project Title:

Review and synthesis of potential hydrologic impacts of mountain pine beetle (MPB) infestation and related harvesting activities in British Columbia (8.30)

Contact:

Dr. John Gibson

University of Victoria

Victoria, BC

john.gibson@ec.gc.ca

Initiative:

Development and delivery of decision support tools to evaluate the impacts of various MPB management scenarios on post-beetle landscapes.

Abstract:

The current mountain pine beetle outbreak in British Columbia started in 1994 and is the most important historically recorded episode. As of 2003, an estimated 164 million m3 of pine had been killed by this infestation in BC and projections estimate that another 70 million m3 per year will be killed until 2008 and more than 30 million m3 per year until 2015. Many economic and environmental impacts of the infestation have been postulated, however, no studies have looked in detail at the effects of MPB infestations on water quantity and quality. The present document is a review of existing literature on large scale bark beetle epidemics and their possible impacts on hydrology and biogeochemistry. It also identifies and discusses probable hydrological and biogeochemical impacts of MPB infestations in BC as well as key knowledge gaps and recommendations for future investigations. In light of the present review of the literature, the current MPB infestation in the interior of BC is likely to damage and/or kill enough trees to significantly change interception and transpiration rates in affected watersheds and thus induce changes in annual water yields, peak flows and low flows. Furthermore, it seems reasonable to expect some nutrient losses in central BC forests through streams and rivers following an MPB infestation. This literature review revealed the importance of the nitrogen cycling as changes in this cycle triggers losses of cations. Nevertheless, it is clear that there are very few studies published on the effects of beetle attacks on the hydrological and biogeochemical cycles of forested watersheds.

Keywords:

mountain pine beetle, hydrological impacts, evapotranspiration, groundwater regime

Links:

Review and synthesis of potential hydrologic impacts of mountain pine beetle and related harvesting activities in British Columbia. 2005. Helie, J.F.; Peters, D.L.; Tattrie, K.R.; Gibson, J.J. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre, Victoira, BC. Mountain Pine Beetle Initiative Working Paper 2005-23. 26 p.