Copyright 2001, Environmental News Network
July 26, 2001

From petroleum development to ecotourism, even small disturbances to fragile Arctic ecosystems may permanently damage them, an international research team has found.

"In the increasingly accessible Arctic, we need to be wary of relatively small and seemingly insignificant disturbances," said principal author Bruce Forbes of the University of Lapland in Rovaniemi, Finland. "Some of the most productive landscapes are being slowly nibbled away."

Senior scientist in environmental science and policy at the Arctic Centre, University of Lapland, Forbes is researching the impacts of tourism on subarctic and alpine tundra and forest tundra in Alaska, Canada, Russia, and Finland.

With coauthors James Ebersole of Colorado College in Colorado Springs and Beate Strandberg of the National Environmental Research Institute in Silkeborg, Denmark, Forbes found that even an event as insignificant as the single pass of a heavy-tracked vehicle can drain an Arctic meadow. The scientists' findings appear in the August issue of the journal Conservation Biology.

In this the first circumpolar assessment of how small human disturbances affect Arctic ecosystems, the researchers found that Arctic ecosystems are at risk from mining, military activities, heavy reindeer grazing, and even from recreational activities such as camping, hiking, and off-road vehicle use.

"In addition to the more obvious and large-scale effects associated with petroleum development, mining, and military activity, the explosive growth of ecotourism is affecting all sectors of the Arctic," said Forbes. "We suggest that serious consideration should also be given to the less visible effects of seemingly benign recreational activities that inevitably accompany tourism development."

The Arctic, defined as lands poleward of the treeline, has large populations of wild caribou and domesticated reindeer and provides critical nesting habitat for immense numbers of shore and water birds.

The most controversial threat to Arctic ecosystems is oil and natural gas development. The United States is considering oil and gas exploration in Alaska's Arctic National Wildlife Refuge. Canada is likely to extract natural gas just east of the refuge, and Russian and northern European energy companies are already operating in the Arctic.

Based on recent existing studies, Forbes and his team evaluated how well Arctic ecosystems recover from human disturbance. The most extreme disturbances completely remove the tundra's plant layer. In these cases only the smallest, wettest patches recovered on their own within 20 to 75 years. Dry patches more than three feet across still had bare centers even after 20 years, largely due to wind erosion.

The researchers also found that lasting changes can result from disturbances that leave the plant layer intact. One of the most widespread disturbances in the Arctic is heavy-tracked vehicles, and driving them through an area only once during the summer can be enough to cause long-term damage.

Dwarf shrubs can die, meadows can drain rapidly and dry out, and the permafrost that most tundra ecosystems depend on can melt. While summer traffic is banned in the North American Arctic, winter traffic can also be damaging if the snow is thin, the researchers found.

People trampling over the tundra can decrease plant biodiversity, favoring willows and rapidly growing grasses over most other plants. The hikers flatten the hummocks and hollows that give geographical diversity, and therefore plant diversity, to the landscape.

"A wide range of small disturbances resulted in reduced species diversity," said Forbes and his colleagues. Error: Unable to read footer file.