More Water Around After Beetle Epidemic
Expect more water flowing after bark beetles finish with pine stands in central British Columbia. Without transpiration from live trees, and without canopies to intercept rain and snow, water tables rise. This gives way to higher low flows and peak flows of water across landscapes.
Studies elsewhere indicate that when precipitation tops 450 mm annually, as it does in central BC, mountain pine beetle epidemics result in increased water yields. But with no BC research completed on hydrological impacts of beetle infestations as of 2005, what magnitude the shifts in water flows will have here is not known.
The beetle epidemic will likely cause water chemistry changes similar to those appearing after clearcutting. The major influence in both situations is a decline in vegetation taking up nutrients. Some of these nutrients will instead wash away in streams. The extent of nutrient loss can vary depending upon biogeochemical cycling regimes within specific ecosystems.
J.F. Helie, D.L. Peters, K.R. Tattrie, J.J. Gibson. 2005. Review and synthesis of potential hydrologic impacts of mountain pine beetle and related harvesting activities in British Columbia. Natural Resources Canada, Canadian Forest Service, Pacific Forestry Centre. Victoria, BC. Mountain Pine Beetle Initiative Working Paper 2005-23.