A salamander on a branch.

What Salamanders and Lichens Can Teach Us about Air Quality in North Carolina
Purchase Knob Uses DAQ Data to Teach about Pollution’s Effect on Wildlife

DEQ Secretary Elizabeth Biser visits Purchase Knob and learns how salamanders, lichens and other native species respond to improvements in air quality.

Author: Keith Bamberger, DAQ Information & Communication Specialist

The Appalachian Highlands Science Learning Center is not someplace you get to by accident.

At the foot of the mountains in southeast Haywood County, ancient tobacco barns, oaks and dogwoods dot the landscape. The road to the top is more twist and turn than anything. On the way up the mountain, you’ll probably lose cell phone signal, and there’s more than one spot where the unknowing driver might make a wrong turn before reaching the learning center.

A group photo with Secretary Biser at the Ozone Garden.

The 3,000-foot climb is accompanied by views of unnamed cascades that explain why 10 million people visit Great Smoky Mountains National Park every year. Closer to the summit, the types of trees in the forest change to beech, birch and buckeyes – trees more common in Maine and northern Michigan than North Carolina.

But the trip is more than worth it. Visitors have fantastic vistas of Mount Mitchell, Cold Mountain and the Southern Blue Ridge Mountains. And the educational program at the Appalachian Highlands Science Learning Center (or Purchase Knob as those who visit often tend to call it) teaches about one of the most unique ecosystems in the state.

Students, teachers and other guests who visit can study air quality by measuring the effects of air pollution on the local flora and fauna – like lichens, flowers and even salamanders. It’s this program that drew North Carolina Secretary for the Environment, Elizabeth S. Biser, to the center earlier this month.

Ozone’s Effect on Plants and Animals

Purchase Knob is home to one of the North Carolina Division of Air Quality’s (DAQ) ground-level ozone monitors. The monitoring station is the center of the science and education that happens at Purchase Knob.

While ozone high in the atmosphere offers protection from harmful sun rays, ground-level ozone is a pollutant that can irritate lungs and eyes and provoke symptoms in sensitive populations, such as those with asthma. It can also be harmful to wildlife. It’s caused when nitrogen oxides from vehicles, power plants and factories combine with volatile organic compounds on warm, sunny days.

Secretary Biser tours the ground-level ozone monitor.
Steve Ensley, a chemist with the DAQ Asheville Regional Office, explains to Secretary Biser how the ground-level ozone monitor works and DAQ’s effort to produce reliable data.

DAQ uses the monitoring station to collect data on ozone levels in western North Carolina and make daily air quality forecasts. This data show that North Carolina has been meeting national air quality health standards for several years now. Great Smoky Mountains National Park and other groups also use the data as a foundation of air quality health research. Educators at Purchase Knob create robust datasets that demonstrate the effects of ozone on lichens, salamanders and plants. Workshops at the park teach educators about these impacts.

Looking for the Stippling

During Secretary Biser’s visit to the Ozone Garden at Purchase Knob on April 6, small early flower buds on the trees hinted at the start of spring around the corner. The twigs from last year’s plants still held a wealth of information about ozone in the area.

It’s important that the DAQ ozone monitor is near the plants where researchers collect data on ozone damage, says Susan Sachs, Education Branch Coordinator, and Paul Super, Science Coordinator at Great Smoky Mountains National Park. Teachers and students can spot that ozone damage, called stippling, in the tops of leaves of the cutleaf coneflower (Rudbeckia laciniata).

Coneflowers grow at Purchase Knob.
By measuring the ozone damage, or stippling, in plants like the leaves of the cutleaf coneflower in the Ozone Garden at Purchase Knob, scientists can learn how air pollution affects western North Carolina.

Twenty years of data on plant stippling along with data on ozone levels from the monitor have been collected and correlated into the national Hands on the Land database. The data show a dramatic improvement in air quality over the last two decades.

The U.S. Park Service has expanded the research by working with partners to plant genetic clones of the Purchase Knob coneflowers at dozens of sites across North Carolina and the nation. Teachers and students in those locations collect stippling data on those plants and share in the same database.

Lichens Depend on the Air

A small path goes into the woods near the ozone monitoring building. Fifty feet into the woods, trees marked with ribbons have strings and clothespins tied around their trunks. This is the Lichen Learning Station.

Scientists estimate that 7% of all living things on earth are lichens, but most people might not even notice them. Those that do might think lichens are some sort of moss. They’re not. Lichens are symbiotic relationship between fungus, algae and sometimes cyanobacteria. These small, gray or green composite organisms are usually attached to rocks, trees, soil or anything else that doesn't move very much. They can also live for a very long time.

Lichens don’t harm what they are growing on because they get all their nutrition and energy from the sun and air. This makes them good indicators of air quality.

Paul Super points to a lichen on a tree.
Paul Super, Science Coordinator at Great Smoky Mountains National Park, points to a type of lichen named after him growing on a tree at Purchase Knob on April 6.

Lichens come in different forms or shapes. Fruticose lichens grow like fruit away from its surface. Folios lichens are leaf-like organisms with two different sides. Crustose lichens are attached to their surface like a crust. The more foliose and fruticose lichens in an environment, the healthier the air quality there.

The researchers at Purchase Knob have been using the same trees to study lichens and air quality for years. They showed Secretary Biser the lichen protocol teachers learn when they attend workshops like the Ground-Level Ozone Workshop hosted by the park and the NC Division of Air Quality each August. The teachers can then use the same protocol with lichen learning centers at their own schools.

Salamanders Are Sensitive to Air Pollution

The Salamander Study Plot at Purchase Knob is the highlight of the educational journey for many visitors to the park.

A hand holds a plastic bag containing a salamader.

Off the trail, hidden in the woods, are 40 disk-shaped slabs of wood cut from trees called tree cookies. Each cookie is numbered and has a corresponding database. One by one, the researchers slowly lift each tree cookie, revealing the animals that live underneath: salamanders. There were several on display for Secretary Biser during her visit.

Salamanders are important to understanding the effects of air pollution. The amphibians breathe through their skins, making them particularly sensitive to air quality. By paying attention to the health of different salamanders and the number of the animals in the wild, scientists can study the connection between air quality and biodiversity. This makes salamanders an important bioindicator for researchers.

Salamander study plots can be found at several other locations in Great Smokey Mountains National Park and at education centers and school across North Carolina. The data collected at these sites are a part of the citizen science project.

Secretary Biser and others look for salamanders.
Secretary Biser counts salamanders as an indicator of how air quality impacts the animals’ health.

Traveling down the mountain, back to your everyday world, your view might be the same, but your perception of nature around you changed. Fallen logs are homes to salamanders and snails. Some trees are covered with sensitive lichens too numerous to count. The mountain vistas may seem a clearer not just because of the things you learned, but also because applied science and policy has improved the air quality. Today, salamanders are healthier and more numerous, and there is a greater variety of lichen, because our air is cleaner.

Related Topics: