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Scientists Discover Link Between Trees and Electricity
An anonymous reader writes "Everyone knows trees give us all oxygen so we can breathe, but according to Australian scientists, they also affect the concentration of positive and negative ions in the air. A team from the Queensland University of Technology's International Laboratory for Air Quality and Health ran experiments in six locations all over Brisbane and found that positive and negative ion concentrations in the air were two times higher in heavily wooded areas than in open grassy areas, such as parks."
Shocking!
That isn't the mechanism the paper is proposing. What the authors suggest is that trees uptake radon dissolved in groundwater, transpire it into the air, and that it is the radioactive decay of radon that would be responsible for the ions released by trees.
"FDA staff reviewers expressed concern about the number of patients who were left out of the study because they died."
This has been known for a very long time and it's very much common knowledge. Ambient negative ion levels can even be obtained through weather services in my country. My Daikin air conditioner even claims to keep ambient ion levels at "lush forest" levels and it's not near new. Just do a google search for "forest negative ion" and you'll find tons of products and articles on the subject. Why is this at all news?
sudo science freaks
Anonymous Coward is not in the sudoers file. This incident will be reported.
http://www.fia.fs.fed.us/library/briefings-summaries-overviews/docs/ForestFacts.pdf
"It is estimated that—at the beginning of European settlement—
in 1630 the area of forest land that would become
the United States was 1,045 million acres or about 46
percent of the total land area. By 1907, the area of forest
land had declined to an estimated 759 million acres or
34 percent of the total land area. Forest area has been relatively
stable since 1907. In 1997, 747 million acres—or
33 percent of the total land area of the United States—
was in forest land. Today’s forest land area amounts to
about 70 percent of the area that was forested in 1630.
Since 1630, about 297 million acres of forest land have
been converted to other uses—mainly agricultural. More
than 75 percent of the net conversion to other uses
occurred in the 19th century."
And it does go on to describe the kinds of differences - one of which you mention - between historical and contemporary forest composition.
46 & 2
We bought 160 acres of densely forested land a while back. The only part not wooded were a few acres at the front that had been used as farmland. One summer we rented a tree planter, pulled it behind a tractor and in a matter of 3 days planted 70,000 trees. (they're really cheap when you buy them in that volume) We also raised turkeys and released them into the wild (illegally) and brought the wild turkey back to the county in question over a period of 10 years or so. As we put out more and more broods the neighbors started getting involved. Some of our neighbors started gathering roadkill and leaving them in piles in strategically placed areas with pre-made nesting boxes... now we have bald eagles. I'm not sure where the bears and cougars came from but I'm sure there are similar stories involving them that I don't know about. The simple fact is, as a child growing up in the 70's, there were NO big game animals in that area besides deer. There were a few grouse and pheasant but that was about it. Now the countryside is so rife with wildlife we're starting to have problems with Car+bear accidents. It's an amazing change. If there's one thing the USA has got going for it, it's the return of the wilderness.