You are here: Home / Research Topics / Research Highlights / Individual Highlight

Research Highlights

Individual Highlight

Lichen Indicate Air Quality Near Natural Gas Wells

Photo of Wolf lichen (Letharia spp.) is a species frequently used to estimate nitrogen deposition in western forests. Jason Hollinger, Wikimedia CommonsWolf lichen (Letharia spp.) is a species frequently used to estimate nitrogen deposition in western forests. Jason Hollinger, Wikimedia CommonsSnapshot : Nitrogen in lichen tissues closely correlates with measured nitrogen deposition in forests near natural gas wells in the Bridger Wilderness, WY. The Clean Air Act mandates that federal land managers protect air quality-related values for Federal Class I parks and wilderness. The mandate involves assessing the impact of new pollution sources and reporting it to local regulators. The study was the first to validate use of lichen tissue indicators for assessing nitrogen in dry interior forests and for detecting low level nitrogen inputs from oil and gas operations.

Principal Investigators(s) :
Jovan, Sarah, Dr 
Research Location : Wyoming
Research Station : Pacific Northwest Research Station (PNW)
Year : 2014
Highlight ID : 663

Summary

Using lichens to assess air quality on public lands is increasingly common, serving as a budget friendly supplement to widely spaced monitoring networks like NADP and IMPROVE. Two common lichen species, Letharia vulpina and Usnea lapponica, were collected from the Bridger Wilderness less than 30 km from a concentration of active oil and gas wells in Sublette County, WY. Lichens accumulate nutrients, such as nitrogen, in excess of metabolic needs, making tissue levels a reflection of atmospheric nitrogen levels. The main objectives were to calibrate nitrogen levels in lichen with co-located nitrogen measurements and determine the extent of nitrogen dispersal into the wilderness. Overall nitrogen levels were relatively low although visual signs of damage to lichens were seen at the highest deposition sites. The results demonstrate that lichen tissue indicators are a simple, accurate tool for nitrogen monitoring.

Forest Service Partners

External Partners

  • Forest Inventory and Analysis -Interior West Region
  • Pacific Southwest Research Station, Pacifi Northwest Region
  • Montana State University