Terrestrial Vegetation and Soils Resource Brief for the Arctic Network

Arctic tundra vegetation of herbs and low shrubs in fall color.

NPS/Dave Swanson

The 5 Arctic parks collectively referred to as the Arctic Network: Bering Land Bridge NP, Cape Krusenstern NM, Noatak National Preserve, Kobuk Valley National Park, and Gates of the Arctic National Park and Preserve.

Why vegetation is important in the Arctic Network

Vegetation is the basis for ecosystem productivity and wildlife habitat. Arctic vegetation is very sensitive to climate change and disturbance such as fire, herbivory, and human activities. Research has documented an increase in shrubs and, to a lesser extent, trees in the Arctic over recent decades, probably related to climate change. Major changes in vegetation structure such as these have a cascading effect on other ecosystem attributes, such as herbivore use patterns, fire regime, and the chemistry of water bodies. In addition to vascular plants such as shrubs and herbs, the Arctic has abundant lichens that provide biodiversity and wildlife forage. Lichens are sensitive to caribou and reindeer grazing, competition from other plants, fires, and contaminants. All of these factors could lead to decreased lichen diversity and biomass in the future.

Arctic Network scientists measure the cover of plants on the tundra in Bering Land Bridge National Preserve using a laser pointer set at regular intervals along a tape measure. Buried magnets allow them to precisely re-locate the position of the plot for future measurements.

NPS/Dave Swanson

How we monitor terrestrial vegetation

Vegetation is monitored using plots that can be relocated exactly and re-measured. These plots are all in remote areas requiring access by airplane or helicopter. We have nearly 500 comprehensive vegetation monitoring plots distributed across the Arctic Network, where we measure a variety of vegetation properties: the cover and height by species of plants (sedges, grasses, forbs, shrubs, and trees); the cover of selected mosses and lichens; and tree diameters and growth rates from cores. We also describe the soil and site characteristics of the plots. We have started re-measuring these plots and expect to visit them all every 10 to 15 years. In addition, in Bering Land Bridge National Preserve we have 16 fenced grazing exclosures with permanent monitoring plots inside and outside, where we measure lichen cover and height. We also have hundreds of lichen species inventory plots around the Network that can be re-visited to detect major changes.

These portable chain-link fences keep caribou and reindeer from grazing lichens in a small area so that scientists can judge their impact on the surrounding areas.

NPS/Peter Neitlich

Locations of ARCN permanent vegetation monitoring. Each location has a lake or flat open area to land an airplane on, a good campsite, and between 10 and 30 plots accessible on foot.

What we want to know about vegetation

• Long-term changes in plant structure: the height and density of plants by species
• Long-term changes in lichen abundance and diversity, and their relation to grazing by caribou or reindeer
• The local history of weather and climate effects on tree growth at the northern limit of trees

An example vegetation monitoring locations in the Noatak National Preserve. The campsite is accessible by a gravel landing strip and 22 monitoring plots are located nearby on different kinds of landscapes.

Monitoring plots in poplar forests near the northern limit of trees in the Noatak Valley of Noatak National Preserve provide an opportunity to study the effect of climate change on trees.

NPS/Dave Swanson

How monitoring vegetation can help park managers protect parks in the Arctic Network

Vegetation monitoring will help us understand changes in habitats that will affect decisions about management of wildlife and fire. Interpretive products will be used to educate the public about how climate change is affecting arctic ecosystems.

For more information, contact:

Dave Swanson
907-455-0665
[e-mail]