RAPID: Collaborative Research: Forest Ecosystem Responses to Interacting Bark Beetle and Fire Disturbance are set up by Regeneration in the First Year

University Of Wyoming, Laramie WY

Investigators

Abstract

Over the past two decades, forests in the western US have experienced increases in bark beetle infestations and higher incidence of forest fires. The resulting tree mortality produces ecosystem responses that affect water quantity and quality, carbon storage, and nutrient cycling, with implications for future forest production and health. Understanding how these two stresses affect forests is critical to the management and availability of water in the western US. This award will significantly contribute to ecosystem models that predict where and how fast carbon, nitrogen and water move in these forests. Results from this study will be shared with regional water and forest managers using the Wyoming Water Forum. Underrepresented and first-generation pre-college students will be involved in the project through the University of Wyoming "Summer Research Apprentice Program". This award will quantify carbon and water fluxes in relation to post-beetle fire intensity, partitioning these fluxes into contributions from the understory plants, overstory plants, and soil. The researchers will further assess the interactive effects between post-beetle fire and vegetation regrowth, specifically in regard to soil water and available soil N. The researchers will take advantage of a recent fire that burned through a beetle-affected lodgepole pine forest in Chimney Park Wyoming. The heterogeneous distribution of burn severity and existing pre-burn data provide a unique opportunity to understand the physical and biological processes that control the water, carbon, and nitrogen cycles within a forest ecosystem following sequential and interacting disturbances. The researchers will measure ecosystem pools and fluxes of carbon dioxide, water, and nitrogen in forest patches of different post-beetle burn intensities (bark beetles only, bark beetles plus understory fire, bark beetles and stand replacing fire) using eddy covariance, sap flow, electrical resistivity tomography, vegetation surveys, and biogeochemical techniques. This study will leverage existing equipment and benefits from an extensive pre-disturbance data set. This award will develop predictions and attribution to biological (e.g. transpiration controlled by plant conductance) and/or physical (e.g. soil evaporation and interception from bare branches) drivers in these forests. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.