2009-06-04
Arctic tundra slow to recover from seismic exploration
http://instaar.colorado.edu/aaar/about_aaar/news_item.php?id=4
JUNE 2009 -- Long-term monitoring is needed to determine the cumulative impact of seismic exploration on tundra in the Mackenzie Delta region says the author of a recently published study. Todd Kemper, who completed the study as part of his graduate degree work at the University of Alberta, and colleague Ellen Macdonald studied the Kendall Island Bird Sanctuary region in the Northwest Territories between 2002 and 2004. Their results, published in the May edition of the journal Arctic, Antarctic and Alpine Research, show that despite new seismic exploration methods designed to reduce impact, vegetation is still being damaged. "We can conclude that on balance, the changes seem to be a moot point or, in some areas, the damage may be worse," said Kemper, stressing his study looks at impacts that occured over the short term. "We can't predict what these areas will look like in 10, 15 or 30 years." The 623-square kilometer Kendall Island Bird Sanctuary is an internationally-known migratory nesting ground for some 60,000 birds. It is also situated above two large natural gas deposits which contain about two-thirds of the gas intended to fill the proposed Mackenzie Valley pipeline. The area has been extensively explored by resource companies since 1965 and work continues today. When seismic exploration began in the 1 940s it was conducted during the summer when soil above the permafrost thawed. But working on this fragile terrain during the warm months caused severe damage and some areas have failed to recover, even today. By the late 60s, companies were sending heavy seismic equipment in during the winter when the tundra was frozen and snow-covered. Even then, trails left by seismic equipment remained damaged for years. In the last 40 years, seismic technology has evolved. Instead of using dynamite, machines have been developed that send vibrations deep underground. In addition, trucks use low-pressure tires designed to minimize tread impact. Still, landscapes are sustaining heavy long-term damage. Plant re-growth in harsh Arctic environments is slow and damaged lines rarely return to their natural state because areas are re-colonized by some but not all of the surrounding plants. The impact of one seismic line is not monumental. Kemper would like to see the establishment of a long-term monitoring program to determine the cumulative impacts of seismic exploration. Once experts understand and document the effects of seismic exploration, effective management programs can be developed.
No comments:
Post a Comment