Tree mortality from drought, insects, and their interactions in a changing climate

Climate change is expected to drive increased tree mortality through drought, heat stress, and insect attacks, with manifold impacts on forest ecosystems. Yet, climate-induced tree mortality and biotic disturbance agents are largely absent from process-based ecosystem models. Using data sets from the western USA and associated studies, we present a framework for determining the relative contribution of drought stress, insect attack, and their interactions, which is critical for modeling mortality in future climates. We outline a simple approach that identifies the mechanisms associated with two guilds of insects - bark beetles and defoliators - which are responsible for substantial tree mortality. We then…

• NS
  National Science Foundation

  Awards: EF‐0553768, EF-0553768
• UO
  University of California
• UC
  University Corporation for Atmospheric Research
• UG
  U.S. Geological Survey
• UF
  U.S. Forest Service
• NC
  National Center for Ecological Analysis and Synthesis