Modelling Long-term Dynamics of MPB in Alberta Under Climate Change

Forest stands in western Canada are subject to both mountain pine beetles (MPBs) and climate change and their ability to respond to joint impacts of these stressors is not clear. There is both opportunity and need for quantitative models to incorporate existing knowledge about each stressor to predict forest responses to their joint impacts. This project develops and applies models to:

1. Estimate changes in long-term susceptibility and resilience of forest stands to MPB in the presence of intermittent MPB outbreaks and climate change.
2. Determine the impact of intermittent MPB outbreaks and climate change on persistence of low-level endemic beetle populations.

Estimation of long-term susceptibility and resilience will build on existing models for stand-level productivity and MPB outbreaks in age-structured forests to include a variable resilience and will assess how the proportion of resilient trees could change with successive MPB infestations.

Objectives

1. Develop and apply models to estimate changes in long-term susceptibility and resilience of forest stands to MPB in the presence of intermittent MPB outbreaks and climate change.
2. Develop and apply models to determine the impact of intermittent MPB outbreaks and climate change on persistence of low-level endemic beetle populations.
   
   We will develop a model incorporating intermittent MPB outbreaks and climate change using two complementary approaches. The first will be deterministic, giving insight as to the key features governing low-level endemic populations. The second will be semiempirical and stochastic, allowing us to fit the model directly to Alberta MPB data. Inasmuch as possible, we will also include the resilience structure of lodgepole, hybrid and jack pine.