Toolshed
07-04-2006, 12:21
Saw this in my local paper this morning:
http://www.mcall.com/entertainment/all-poisonivyjul04,0,7580645.story?coll=all-ent-hed[/URL]
Poison Ivy
Greenhouse gas could spawn itchier vine, study suggests
By Mariella Savidge Of The Morning Call
Prediction: You're gonna need an ocean of calamine lotion.
More potent and more plentiful poison ivy could be on its way, according to a paper published June 13 in the Proceedings of the National Academy of Sciences.
The findings may help to humanize the notion of ''global warming,'' taking it out of the realm of Al Gore, Kyoto and greenhouse gases, and bringing it down to terms that the 85 percent of people on the planet can actually feel. And scratch.
A six-year experiment at Duke University's Free-Air CO2 Enrichment lab in North Carolina found that in an environment that experiences the same environmental conditions as our own backyards — such as sunlight, deer and drought — poison ivy thrives when exposed to elevated levels of carbon dioxide.
Carbon dioxide is a greenhouse gas produced during the combustion of fossil fuels. Global deforestation exacerbates increasing CO2 levels since there are fewer trees to absorb it, says Jonathan R. Cumming, chairman of the biology department at West Virginia University.
In ever increasing levels, carbon dioxide is trapping the sun's energy in the atmosphere, thereby contributing to global warming.
Jacqueline E. Mohan, now a postdoctoral scientist at the Marine Biology Laboratory in Woods Hole, Mass., and the first author on the FACE report, says there are some who scoff at the findings because everybody knows plants need carbon dioxide to photosynthesize.
Exposure to more would certainly be good news for the plants, they say. No big deal.
Indeed, on average, a plant will grow 30 percent faster with elevated exposure to carbon dioxide, Mohan says.
''But poison ivy grew 149 percent faster,'' she says, and though urushiol — the part of the plant that causes the itchy, red rash on skin — does not increase in volume, it becomes more potent.
''It's just nasty,'' she says.
For the poison ivy experiment, scientists fitted six circles 100 feet in diameter with PVC piping laid on the forest floor and extended vertically to the tops of the trees. Air enriched with carbon dioxide was pumped through the pipes in three of the circles and untreated air was pumped through the other three.
The gas pumped through the control circles contained 380 parts per million of carbon dioxide, similar to the air we currently breathe, Mohan says.
The circles with elevated carbon dioxide carried air infused with 580 parts per million of CO2, a projection of what the air would be like in 40 to 50 years, if steps are not taken to reduce pollution.
The experiment was launched in response to work by scientists in the Amazon regions who noticed that woody vines were becoming more plentiful and there seemed to be fewer trees.
The study was not initiated as a look solely at poison ivy, says Richard B. Thomas, a biology professor at West Virginia University who is another of the seven authors of the study and part of the Duke FACE experiments for 15 years.
''We started by asking what would happen if we enriched an ecosystem with CO2. Where would it end up — in the trees? Roots? Soil? The poison ivy growth raised interesting questions about what's happening to vines,'' Thomas says.
The realization that vine growth was killing trees was startling to the scientists.
mariella.savidge@mcall.com
610-778-2253
http://www.mcall.com/entertainment/all-poisonivyjul04,0,7580645.story?coll=all-ent-hed[/URL]
Poison Ivy
Greenhouse gas could spawn itchier vine, study suggests
By Mariella Savidge Of The Morning Call
Prediction: You're gonna need an ocean of calamine lotion.
More potent and more plentiful poison ivy could be on its way, according to a paper published June 13 in the Proceedings of the National Academy of Sciences.
The findings may help to humanize the notion of ''global warming,'' taking it out of the realm of Al Gore, Kyoto and greenhouse gases, and bringing it down to terms that the 85 percent of people on the planet can actually feel. And scratch.
A six-year experiment at Duke University's Free-Air CO2 Enrichment lab in North Carolina found that in an environment that experiences the same environmental conditions as our own backyards — such as sunlight, deer and drought — poison ivy thrives when exposed to elevated levels of carbon dioxide.
Carbon dioxide is a greenhouse gas produced during the combustion of fossil fuels. Global deforestation exacerbates increasing CO2 levels since there are fewer trees to absorb it, says Jonathan R. Cumming, chairman of the biology department at West Virginia University.
In ever increasing levels, carbon dioxide is trapping the sun's energy in the atmosphere, thereby contributing to global warming.
Jacqueline E. Mohan, now a postdoctoral scientist at the Marine Biology Laboratory in Woods Hole, Mass., and the first author on the FACE report, says there are some who scoff at the findings because everybody knows plants need carbon dioxide to photosynthesize.
Exposure to more would certainly be good news for the plants, they say. No big deal.
Indeed, on average, a plant will grow 30 percent faster with elevated exposure to carbon dioxide, Mohan says.
''But poison ivy grew 149 percent faster,'' she says, and though urushiol — the part of the plant that causes the itchy, red rash on skin — does not increase in volume, it becomes more potent.
''It's just nasty,'' she says.
For the poison ivy experiment, scientists fitted six circles 100 feet in diameter with PVC piping laid on the forest floor and extended vertically to the tops of the trees. Air enriched with carbon dioxide was pumped through the pipes in three of the circles and untreated air was pumped through the other three.
The gas pumped through the control circles contained 380 parts per million of carbon dioxide, similar to the air we currently breathe, Mohan says.
The circles with elevated carbon dioxide carried air infused with 580 parts per million of CO2, a projection of what the air would be like in 40 to 50 years, if steps are not taken to reduce pollution.
The experiment was launched in response to work by scientists in the Amazon regions who noticed that woody vines were becoming more plentiful and there seemed to be fewer trees.
The study was not initiated as a look solely at poison ivy, says Richard B. Thomas, a biology professor at West Virginia University who is another of the seven authors of the study and part of the Duke FACE experiments for 15 years.
''We started by asking what would happen if we enriched an ecosystem with CO2. Where would it end up — in the trees? Roots? Soil? The poison ivy growth raised interesting questions about what's happening to vines,'' Thomas says.
The realization that vine growth was killing trees was startling to the scientists.
mariella.savidge@mcall.com
610-778-2253