Scientists Coax Carbon into Reclaimed Mine Lands, Forests

Three University of Wyoming researchers are attempting to determine best-management practices to harness the Earth's primal forces and turn landscapes into sponges for carbon. Or, at least through the efforts of Pete Stahl, Daniel Tinker, and George Vance, find more efficient ways to coax carbon out of the atmosphere and stick it in the ground.

Stahl, associate professor in the College of Agriculture's Department of Renewable Resources, is peering into ways reclaimed mining land can be best managed to absorb carbon in the atmosphere.

"More and more scientists believe global warming is a real phenomenon," he says. "If we can come up with ways to keep carbon out of the atmosphere, that can be really important."

Wyoming's surface mining legacy offers a unique test tube to examine best-management practices of grazing, topsoil replacement methods, mulch use, and grass and forb seed.

Stahl compares sites on a half-dozen Wyoming coal mines. Since mining companies are required to keep records of their land reclamation efforts, there is a long-term canvas for comparisons.

One area, near Hanna, has been so successfully reclaimed that "if you go up there, you wouldn't know a mine was ever there," Stahl notes.

Stahl samples soil at three depths - from 0-5 centimeters, 5 to 15 centimeters, and 15 to 30 centimeters - to determine the amount of soil organic matter.

He's had at least one instance that raised his eyebrows. Rangeland reclaimed from surface mines and grazed by domestic livestock and wildlife seems energized.

"The mining companies are doing such a good job reclaiming that there is a period those sites are more productive than undisturbed sites," he says.

Re-establishing the plant community takes a few years, and then the site enters an extremely productive span for several more years.

Another, not quite "Aha!" moment but still an illuminating one, was his revisit of the Hanna site.

"We saw that the amount of organic carbon in the soil had increased so much. Sagebrush had re-established on the reclaimed mine land, which is significant because it captures much of the snow," he says.

Stahl also is examining best forest management practices in the Medicine Bow National Forest and another area in the Black Hills in northeastern Wyoming with Vance, an environmental soil science professor in the Department of Renewable Resources, and Tinker, an assistant professor in the Department of Biology.

"We are looking at how different forest management practices influence carbon levels in the soil," Stahl notes.

Researchers had to first estimate how much carbon exists in above- and below-ground plant material before they could determine any rates of replacement.

That's where Tinker, who also has ongoing research projects in the Yellowstone area, put his forestry expertise to use.

Tinker looked at three timber stands that were being managed differently and one stand where there has been no forest management. Tinker's team had to determine the amount of carbon in each of the above- and below-ground pools, and then somehow determine how much carbon was being sequestered each year.

To solve the first problem required lots of manual labor coupled with the development of mathematical equations. To solve the second problem required a skill almost anyone who has ever felled a tree knows; however, gathering the data was not easy.

Tinker had to develop allometric equations, which relate easily-measured tree characteristics, such as diameter, to the entire tree to determine the biomass.

"We had to cut down lots of trees and weigh individual parts," he explains. "The only way is to cut a tree into little pieces and weigh the pieces in the field."

They felled 80 trees. The chunks then had to be dried and weighed again to discount moisture. The researchers established total mass of the individual components, including roots, stems, branches and needles.

Scientists then looked at tree rings to determine the amount of carbon stored each year. Tinker observed the biomass in the three sites - even-age management where trees of the same age were left standing, uneven-age management where there has been more selection in the trees removed, and uneven-age management areas that were more intensely harvested.

Tinker says that while the unmanaged stand contains more biomass in the current pools, all three managed areas probably are storing carbon at higher rates than the unmanaged area. He cautions the data provide only a snapshot of conditions over the last five years.

Source: University of Wyoming

Related stories:

Complex dynamics underlie bark beetle eruptions
Forest management that favors single tree species and climate change are just two of the critical factors making forests throughout western North America more susceptible to infestation by bark beetles, according to an article published in the June 2008 BioScience.
Scorched Earth millenium map shows 'fire scars'
A geographer from the University of Leicester has produced for the first time a map of the scorched Earth for every year since the turn of the Millennium.
Think green to reduce nanotech hazards
The University of Oregon's Jim Hutchison already holds three patents in the emerging field of nanotechnology as well as leadership roles in organizations that promote the technology's potential in materials science and medicine.
Wildfire drives carbon levels in northern forests
Far removed from streams of gas-thirsty cars and pollution-belching factories lies another key player in global climate change. Circling the northern hemisphere, the conifer-dominated boreal forests - one of the largest ecosystems on earth - act as a vast natural regulator of atmospheric carbon levels.
MIT model compares environmental, economic effects of emissions bills
While Congress considers seven bills that aim to limit America's greenhouse gas (GHG) emissions, MIT researchers have offered an analysis of the legislation based on a powerful model they created.
Choosing the Right Trees Can Affect Air Quality
Cities can improve their air quality simply by planting the right mix of trees for their climate, according to a study by researchers at the SUNY College of Environmental Science and Forestry (ESF).
An Elephant Tail: New Method Tracks Endangered Critters
By analyzing chemicals in tail hair from elephants that wore radio collars, researchers tracked the diet and movements of elephants in Kenya – a method aimed at reducing human-elephant conflicts and determining where to establish sanctuaries to protect the endangered creatures.
NASA Unveiled Internet Software Tools for Carbon Management
NASA scientists have recently unveiled Internet software tools that will aid in the removal of carbon dioxide from the atmosphere. Researchers at NASA's Ames Research Center (ARC), Moffett Field, Calif, developed the CQUEST science information visualization and modeling software. It enables government agencies, land managers and farm cooperatives to display, predict and analyze carbon dioxide (CO2) fluxes in U.S. ecosystems. The application uses 'what if' scenarios, so land managers can decide where and when planting trees, mixing agriculture with trees or restoring native grasslands are effective for 'sponging up' CO2 emitted into the atmosphere by industrial activities.

News discussion:

Space & Earth science news