Page 12 - The Bell Tower - Summer/Fall 2015

Adventurous Professor
Professor Dr. Peter Nelson, a lichenologist who teaches at the University of Maine at Fort Kent, returned in April from a research trip to study the organisms in the Atacama Desert in Alto Patache, Chile.
It was a round trip journey of over 12,000 miles and occurred during the same time that torrential rains were flooding vast areas of Chile south of Alto Patache. Yet while Chile was seeing ten years worth of rain covering parts of the countryside in just a few days, hundreds of miles up the west coast of South America, Nelson was conducting research in a place so dry that the last time it rained was in 1997. “In the interior of the Atacama Desert, there has never been recorded precipitation, ever,” he said.
Yet some organisms are able to thrive in
the region, and one group is a special class of organism that most people easily mis- take for a plant. A lichen is actually a com- bination of up to three organisms - algae, cyanobacteria, and fungus - that form a composite organism that relies on a symbi- otic relationship to survive, according to Dr. Nelson.
The team, which included primary investigator Daniel Stanton from the University of Minnesota and Chilean lichenologist Reinaldo Vargas, used
a $15,000 grant from the National Geographic Committee on Research and Exploration to study how the shapes of lichens regulate water.
The source of the water, in a place
that last saw rain almost 20 years ago, comes from a dense fog that rolls in from the Pacific Ocean. “The fog forms from
the temperature and moisture difference between the arid land air mass and humid oceanic air mass that meet at Alto Patache. As the air rises being pushed up the moun- tain slope by prevailing westerly winds, the
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oceanic air further cools and loses its mois- ture through the formation of fog,” said Nelson.
The three researchers took samples along several 100-meter long strips of land that followed the contours of the terrain so each strip remained at the same altitude within that strip. The researchers sampled different strips, or transects, at various alti- tudes to compare the lichens they found. The researchers had a hypothesis that the shape of the lichen would change depend- ing on the fog. “They should get taller as they get farther and farther into the fog,” said Nelson.
The scientists were correct. Additionally, the diversity of lichens changed depending on the fog. “The peak lichen diversity was where we expected, which was the densest portion of the fog.”
The team is still analyzing their data, but Nelson said the early results show their hypothesis is correct.
They also took the opportunity to map a square kilometer of a unique basin where
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