Innovation: The Hydrologic Response Of Watersheds To Pine Beetle Infestation In The Black Hills

Mar 25, 2016

Harney Peak in the Black Hills during the Pine Beetle infestation that killed thousands of trees.

Dr. Scott Kenner, head of the Department of Civil & Environmental Engineering at SD School of Mines and Technology and his Grad student Brian Freed join Innovation to discuss their research looking at the hydrologic response of watersheds to pine beetle infestation. Mountain pine beetle infestation has affected large areas of the central and southern Black Hills of western South Dakota.  There is a need for studies of the hydrologic response of ponderosa pine (Pinus ponderosa) forests, which are not a snow-dominated system, but are rather semi-arid settings where evapotranspiration potentially plays a greater role in the hydrologic budget. The research models simulate changes in the hydrologic response since 2008 of Black Hills watersheds to the cycle of beetle infestation, tree mortality, and regrowth.  Projected response from the year 2015 to 2030 was simulated on the basis of climate model simulations and various synthetic climate scenarios. Each climate scenario was run with and without the tree mortality from the mountain pine beetle to determine the potential effects caused by the infestation. Results show a maximum increase in mean annual streamflow of 7 percent in the Upper Rapid Creek watershed during the wettest climate scenario, with other basins showing similar results. The changes to streamflow from the mountain pine beetle infestation during normal or dry climatic conditions are perceived to be negligible compared to the annual variability of the watersheds examined. This study is a cooperative effort between the U.S. Geological Survey, South Dakota School of Mines and Technology, and the City of Rapid City.