Dr. Monica G.Turner
Department of Integrative Biology
University of Wisconsin
430 Lincoln Dr.
Madison, WI 53706
Ecosystem and
Landscape Ecology Lab
 

Field Photos

Jake at Yellowstone National Park

beetle damage

aerial beetle damage

Influence of host tree species on ecosystem response to bark beetle outbreak and salvage logging in subalpine forests of the Greater Yellowstone Ecosystem

Contacts

Jake Griffin

Keywords

lodgepole pine; Douglas-fir; soil nitrogen; chronosequence; disturbance ecology; disturbance interactions;

Project Summary

Disturbances in forests can be strong drivers of ecosystem structure and function, often resulting in both long- and short-term alterations to biogeochemical cycling. Subalpine forests of the Greater Yellowstone Ecosystem (GYE) experience a wide range of natural and anthropogenic disturbances, and often multiple disturbance types affect the same piece of forest in series (i.e. salvage logging following fire or insect damage). Understanding how both individual and combinations of disturbance types influence forest biogeochemistry will help predict the long term consequences of disturbance for soil fertility, nutrient availability, regeneration, carbon sequestration, and biodiversity.

The GYE is currently experiencing outbreaks of several native bark beetle species, each specialized to attack a particular host tree species. Effects of bark beetle outbreak on forest structure and biomass fluxes (e.g. host mortality and litterfall) are similar across multiple host-insect pairings, however host tree species may have unique life history traits and biogeochemical profiles which influence ecosystem response to outbreak. In this study, we compare ecosystem response in lodgepole pine (Pinus contorta Dougl.) and Douglas-fir (Pseudotsuga menziesii ) forests infested by the mountain pine beetle (Dendroctonus ponderosae Hopkins) and Douglas-fir beetle (Dendroctonus pseudotsuga Hopkins), respectively. We also compare the effects of beetle outbreak alone to the combined effects of outbreak and subsequent salvage logging. We hypothesize that differences in litter quality, pre-disturbance soil characteristics, and host tree life history traits will result in host-specific changes to soil nutrient availability, cycling rates, and regeneration following beetle and beetle/salvage disturbance. Results from this study will increase the ability to identify potential feedback mechanisms on post-outbreak soil fertility, regeneration, and herbaceous diversity, as well as provide comparisons to the biogeochemical changes induced by other disturbance types in these forests.

Read more about related research being conducted in the Turner lab....

Key Findings

Field studies began in the summer of 2007.  Data and sample analyses are in progress.

Selected Publications

In progress

Acknowledgements

This study is funded by grants from both the Joint Fire Sciences Program and the Western Wildlands Threat Assessment Center of the USFS.