Evaluating the use of forest health as an indicator of air quality

Meet Robert Smith

Evaluating the use of forest health as an indicator of air quality

Robert Smith, PhD, examined the impacts of air quality and atmospheric changes on forest health. Photo Credit: Robert Smith

Forests and forest vegetation are two of the most important contributors to atmospheric air quality and health of the global environment. According to the US Forest Service (USFS), a mere 100 trees can remove over 53 tons of carbon dioxide and 430 pounds of other air pollutants from the air per year. Forests are also sensitive to environmental changes, such as air pollution, climate changes and human activity. As a result, forest health can be a key indicator of air quality. During a fellowship with the USFS Research Participation Program, Robert Smith, PhD, gained experience conducting research on air quality and atmospheric conditions in relation to forestry and forest health.

The USFS Research Participation Program helps train a diverse and highly talented pool of scientists and engineers to address agricultural, natural resource and technology issues in fields of specific interest to the Forest Service.

For his appointment, Smith was stationed in Washington, DC, where he contributed to ongoing efforts of the USFS Air Resources Management Program. Under the mentorship of Linda Geiser, PhD, Air Program National Leader, Smith conducted research examining changes in forest health by three main angles: 1) creating a lightweight web-based tool for push-button reports of wilderness air quality; 2) refining lichen biomonitoring by accounting for the interaction of climate with air quality; and 3) developing novel analytical techniques to forecast “hotspots” of forest vulnerability where species occur at the outer envelope of their environmental tolerances.

This fellowship has given me an expanded professional network, opportunities to continue applied research, and a sense of helping advance the science that will improve forest management."

The results of each area of Smith’s research offer significant value to the forestry community. The wilderness air quality reporting tool Smith helped develop uses epiphytic lichen responses to grant USFS specialists access to consistent air quality information. Lichens are very sensitive to atmospheric conditions because they get all of their nutrition and moisture directly from the air, making them good indicators of air quality and air quality changes.  The reporting tool lets users from more than 300 wilderness areas download maps and detailed trend analyses at the push of a button, making information instantly available without requiring statistical expertise.

When interpreting lichen responses as air quality indicators, Smith uses statistical adjustment to “subtract” the confounding effects of climate, leaving only the residual signal of air pollution. This helps USFS specialists correctly interpret lichen-based pollution scores, allowing for a better gauge of air quality changes.

Finally, the web-based mapping tool detailing forest health and vulnerability helps forest managers identify locations where climate and pollution constraints may intersect to amplify vegetation damage. The tool, which Smith helped develop in cooperation with the USFS Special Technology Development Program (STDP), focuses on vulnerability analysis. This is important because stressed trees at their physiological limits may be more susceptible to insect or disease damage at large scales.

As a whole, Smith’s research will help anticipate how forests will respond to rapidly changing conditions. This includes conditions such as persistent air pollution, warming and drying climates, increasing prevalence of large stand-replacing wildfires and growing pressure from human land-use. 

“Understanding forest vegetation change is critical for anticipating future trends and for managing their consequences for human communities and livelihoods,” said Smith.

“Like our own personal health, we may only come to realize the value of forest health and ecological integrity when it is gone! The average American may never visit a forest but will nevertheless benefit from what forest vegetation provides: clean air, soil and watershed protection, timber and other forest products and cultural value. This research will establish new ways to detect early warning signs of air deterioration, which impacts the health and welfare of millions of Americans.”

Throughout the course of his fellowship, Smith gained experience in many different fields and developed his skills as a researcher. He describes his experience as very positive and recommends the program to anyone who wants to advance applied science in a way that is genuinely impactful.

“This fellowship has given me an expanded professional network, opportunities to continue applied research, and a sense of helping advance the science that will improve forest management,” said Smith.

“I have access to new resources, experts, and the deep experience of my mentor and cooperators.  My mentor has gone out of her way to ensure I am well-positioned for the next stage of my career progression.”

Following the conclusion of his fellowship, Smith hopes to contribute to the advancement of teaching, research and mentorship by building bridges between academia and agencies.

The U.S. Forest Service Research Participation Program is funded by the Water, Fish, Wildlife, Air and Rare Plants Office at national headquarters and the Pacific Northwest Region’s Forest Inventory and Analysis Program and Forest Health Protection Program. The Program is administered through the U.S. Department of Energy’s (DOE) Oak Ridge Institute for Science and Education (ORISE). ORISE is managed for DOE by ORAU.