|
|
Article: No silver lining.(News from the world of Trees)(acid rain and soil changes)
- Article from:
- American Forests
- Article date:
- September 22, 2005
- Author:
CopyrightCOPYRIGHT 2005 American Forests. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
|
Scientists have long recognized that trees require calcium for healthy growth. More recently they have speculated that acid rain robs trees of this vital nutrient by leaching it from the soil and by mobilizing aluminum, which interferes with calcium uptake by roots. However, a lack of soil data from before the acid-rain era--which began after World War II--frustrated attempts to trace the connection.
That impediment was removed a few years ago when U.S. Geological Survey scientist Greg Lawrence learned of the Dokuchaev Central Soil Museum, near St. Petersburg, Russia, a unique repository of soil samples that date back nearly a century.
"We've known that ...