Ozone Effects on Tree Growth in the United States: 2024 UPDATE

The effects of deposition upon particular tree species can determine the resilience of forests in the face of other anthropogenic stressors like climate change.  Critical loads determined by Horn et al (2018) have allowed NPS to describe the effects of nitrogen and sulfur deposition upon tree growth and tree survival for widespread and abundant tree species.  We have followed the approach of Horn et al, testing and comparing multiple models for tree growth and survival using the USFS Forest Inventory and Analysis data.  However, we have expanded the models to include a more flexible range of responses to N and S deposition as well as tree response to ozone exposure.  This presentation will focus on ozone effects on tree growth and provide an update on model selection decisions and methodology. 

Impact/Purpose

The purpose of this effort is to assess the impacts of ozone air pollution on forests across the U.S.  This study used the USDA Forest Service (USFS) Forest Inventory and Analysis (FIA) dataset to assess the effects of ozone on the growth and survival of ~150 tree species across the contiguous U.S.  We found that there were many species that showed a negative growth response to ozone exposure.  This information will help federal, state, and local managers and decision makers better understand how forests may be impacted by ozone air pollution. 

Citation

Felker-Quinn, E., K. Novak, J. Herrick, K. Austin, G. Martin, M. Salem, J. Phelan, AND C. Clark. Ozone Effects on Tree Growth in the United States: 2024 UPDATE. 2024 NADP Fall Meeting and Scientific Symposium: Protecting the Health of Communities and Ecosystems in a Changing Climate, Duluth, MN, November 04 - 08, 2024.