Post by jonsdigs on Nov 15, 2006 8:18:05 GMT -5
Microbes thriving in Kartchner caves
By Dan Sorenson
Arizona Daily Star
Tucson, Arizona | Published: 11.15.2006
Kartchner Caverns State Park's Big Room is part of a $1.6 million National Science Foundation grant to study microbial activity since humans have begun visiting the cave.
Photos by Dean Knuth / Arizona Daily Star
The jury is still out on our effect on Kartchner Cavern's mama bats, but we're a big hit with cave slime.
Since humans started visiting in numbers — the cave opened in 1999 — some microscopic cave species are "getting fat and happy," said Raina Maier, a University of Arizona professor of soil, water and environmental science studying the cave's microbes.
Maier heads a UA team recently awarded a five-year, $1.6 million National Science Foundation grant to monitor microbial activity in the caves 50 miles southeast of Tucson.
Although the National Science Foundation-funded portion of the study is just getting under way, Maier said ongoing work at Kartchner shows that the microbes that appear to be thriving aren't directly connected with humans. But, she said, it's likely they're thriving thanks to the nutrients cave visitors leave behind.
She said human visitors inadvertently leave behind skin cells, hair and lint, which can become food for microbes.
In the case of the aforementioned bacterial slime, the manmade dinner is even more disgusting than skin, hair and lint. Maier said what got researchers' attention in the first place was "a copious slime" living and dining on paint that had been applied to Fiberglass housings concealing electrical and plumbing systems.
But in parts of the cave far off the human path, it's apparently still slim picking for microbes. Nearer the human pathways, the microbes are living higher on the hog, though it could not be called "nutrient rich," said Maier.
Oddly enough, though microbes near the human paths appear to be thriving, there are fewer species of microbes close to pathways (22 to date) than in areas more removed from humans (32 species, so far), said Maier.
It is not yet clear how the suspected nutrients get to the microbes, though Maier said she suspects that the lint and skin cells become airborne in the damp cave air and stick to the humid walls, where they become food for the miniature creatures.
Monday night, soon after the last of the day's tourists cleared out, project scientists took samples in trailside and remote sites in Kartchner's Big Room.
Maier said they will return to take samples twice a year, being careful to take samples in exactly the same spots each time.
That presents something of a problem, because Global Positioning Systems don't work in a cave and researchers don't want to make any permanent markings to deface the cave, said Leland Pierson III, a project co-principal investigator and a UA assistant professor of plant pathology.
Microbes — a broad term encompassing all microscopic organisms — are of interest to scientists for several reasons, some of them having to do with the health of the cave and others possibly having to do with the health of humans outside.
The National Science Foundation grant for the Kartchner microbial observation work is part of a foundation-sponsored worldwide microbial monitoring program. While microbes make up a large part of the "tens of millions of living organism on Earth, only about 1.75 million have been scientifically described."
According to the Science Foundation's program literature, some microbes crucial to the food web produce lifesaving drugs or "harmful algal blooms" — suggesting that there may be much to be gained from discovering and studying those that are as yet unknown.
As the only cave in the study, Maier said Kartchner has a unique place in the Science Foundation's worldwide network of these microbial observation stations.
Among the questions that may be answered at Kartchner Caverns are whether microbes have a role in the creation of the cave's formations — stalactites and stalagmites — said Maier and Robert Casavant, a UA researcher and staff scientist for Arizona State Parks.
So far, Maier said, none of the microbes identified are connected with humans. Maier said samples are being gathered from areas near and far from the walkways tramped by about 200,000 each year.
Other researchers have been tracking the annual comings and goings of a population of cave myotis bats that come to the cave near Benson every year to give birth. So far, the bats are still showing up in early spring and leaving in the fall, as expected.
Kartchner's Big Room, one of two tour areas that are part of the same cavern system, is closed while it serves as a bat maternity ward and nursery.
The work could have political and economic, as well as the scientific, implications.
"This is still an open question," said Maier. "We do not know what these changes mean for the health of Kartchner and we will use this grant to help (answer) this question. I am very pleased that even though we have documented changes in the microbial community due to tourism, the types of microbes we find are not associated with humans. I think this portends well for the long-term health of the cave."
Kartchner brings in about $3 million annually, between admission fees and the state's take of concessions, said Arizona State Parks spokeswoman Ellen Bilbrey.
It also has economic impact for nearby Benson, Sierra Vista and tourism in Southeastern Arizona.
Humans are relative newcomers to the caves, discovered by two cavers — Randy Tufts and Gary Tenen — in 1974. They kept their discovery relatively quiet until 1978, when they told the property's owners, James and Lois Kartchner. The property was purchased as a state park and opened to the public in 1999.
Article
By Dan Sorenson
Arizona Daily Star
Tucson, Arizona | Published: 11.15.2006
Kartchner Caverns State Park's Big Room is part of a $1.6 million National Science Foundation grant to study microbial activity since humans have begun visiting the cave.
Photos by Dean Knuth / Arizona Daily Star
The jury is still out on our effect on Kartchner Cavern's mama bats, but we're a big hit with cave slime.
Since humans started visiting in numbers — the cave opened in 1999 — some microscopic cave species are "getting fat and happy," said Raina Maier, a University of Arizona professor of soil, water and environmental science studying the cave's microbes.
Maier heads a UA team recently awarded a five-year, $1.6 million National Science Foundation grant to monitor microbial activity in the caves 50 miles southeast of Tucson.
Although the National Science Foundation-funded portion of the study is just getting under way, Maier said ongoing work at Kartchner shows that the microbes that appear to be thriving aren't directly connected with humans. But, she said, it's likely they're thriving thanks to the nutrients cave visitors leave behind.
She said human visitors inadvertently leave behind skin cells, hair and lint, which can become food for microbes.
In the case of the aforementioned bacterial slime, the manmade dinner is even more disgusting than skin, hair and lint. Maier said what got researchers' attention in the first place was "a copious slime" living and dining on paint that had been applied to Fiberglass housings concealing electrical and plumbing systems.
But in parts of the cave far off the human path, it's apparently still slim picking for microbes. Nearer the human pathways, the microbes are living higher on the hog, though it could not be called "nutrient rich," said Maier.
Oddly enough, though microbes near the human paths appear to be thriving, there are fewer species of microbes close to pathways (22 to date) than in areas more removed from humans (32 species, so far), said Maier.
It is not yet clear how the suspected nutrients get to the microbes, though Maier said she suspects that the lint and skin cells become airborne in the damp cave air and stick to the humid walls, where they become food for the miniature creatures.
Monday night, soon after the last of the day's tourists cleared out, project scientists took samples in trailside and remote sites in Kartchner's Big Room.
Maier said they will return to take samples twice a year, being careful to take samples in exactly the same spots each time.
That presents something of a problem, because Global Positioning Systems don't work in a cave and researchers don't want to make any permanent markings to deface the cave, said Leland Pierson III, a project co-principal investigator and a UA assistant professor of plant pathology.
Microbes — a broad term encompassing all microscopic organisms — are of interest to scientists for several reasons, some of them having to do with the health of the cave and others possibly having to do with the health of humans outside.
The National Science Foundation grant for the Kartchner microbial observation work is part of a foundation-sponsored worldwide microbial monitoring program. While microbes make up a large part of the "tens of millions of living organism on Earth, only about 1.75 million have been scientifically described."
According to the Science Foundation's program literature, some microbes crucial to the food web produce lifesaving drugs or "harmful algal blooms" — suggesting that there may be much to be gained from discovering and studying those that are as yet unknown.
As the only cave in the study, Maier said Kartchner has a unique place in the Science Foundation's worldwide network of these microbial observation stations.
Among the questions that may be answered at Kartchner Caverns are whether microbes have a role in the creation of the cave's formations — stalactites and stalagmites — said Maier and Robert Casavant, a UA researcher and staff scientist for Arizona State Parks.
So far, Maier said, none of the microbes identified are connected with humans. Maier said samples are being gathered from areas near and far from the walkways tramped by about 200,000 each year.
Other researchers have been tracking the annual comings and goings of a population of cave myotis bats that come to the cave near Benson every year to give birth. So far, the bats are still showing up in early spring and leaving in the fall, as expected.
Kartchner's Big Room, one of two tour areas that are part of the same cavern system, is closed while it serves as a bat maternity ward and nursery.
The work could have political and economic, as well as the scientific, implications.
"This is still an open question," said Maier. "We do not know what these changes mean for the health of Kartchner and we will use this grant to help (answer) this question. I am very pleased that even though we have documented changes in the microbial community due to tourism, the types of microbes we find are not associated with humans. I think this portends well for the long-term health of the cave."
Kartchner brings in about $3 million annually, between admission fees and the state's take of concessions, said Arizona State Parks spokeswoman Ellen Bilbrey.
It also has economic impact for nearby Benson, Sierra Vista and tourism in Southeastern Arizona.
Humans are relative newcomers to the caves, discovered by two cavers — Randy Tufts and Gary Tenen — in 1974. They kept their discovery relatively quiet until 1978, when they told the property's owners, James and Lois Kartchner. The property was purchased as a state park and opened to the public in 1999.
Article