Helga Van Miegroet Honored by Soil Science Society of America

Utah State University soil scientist Helga Van Miegroet takes a deep view of the world. In her mind, a little bit of green is growing above the really interesting stuff.

Van Miegroet was recently honored by the Soil Science Society of America. In recognition of her service as associate editor of the Soil Science Society of America Journal, she received the Editor’s Citation for Excellence.

 

“Soil is the underpinning of all terrestrial ecosystems,” says the associate professor who has appointments in both the Department of Wildland Resources and the Department of Watershed Sciences. “We need to be looking more closely at what’s going on under our feet.”

 

In light of global climate change and its impact on the planet, Van Miegroet especially encourages closer examination of carbon in soils.

 

“Three times more carbon is stored below the ground than above,” she says. “Soil is the iceberg of terrestrial ecosystems. We shouldn’t just be looking at the tip.”

 

The Titanic, she warns, was tanked by the iceberg.

 

For the past three years, Van Miegroet and colleagues have been involved in a research project at USU’s T.W. Daniel Experimental Forest in Utah’s Logan Canyon to determine how well soils under four adjacent and varied ecosystems are able to store carbon and how stable that carbon is. With Janis Boettinger and Scott Jones of the Department of Plants, Soils and Biometeorology, and Michelle Baker, Department of Biology, Van Miegroet tested the physical, biological and chemical properties of carbon in soil samples collected from a grass-forb meadow, a tract of sagesteppe, a conifer forest and an aspen forest.

 

Van Miegroet and team’s research was funded by a USU Community/University Research Initiative grant, a National Science Foundation ADVANCE grant, the USU Water Initiative and McIntire-Stennis funds from USU’s Agricultural Experiment Station.

 

Initial findings indicate that the type of vegetation has minimal effect on the quantity of carbon storage in soil, says Van Miegroet. “How much is stored appears to be driven, rather, by climate,” she says.

 

While the type of vegetation in the seasonally dry wildland ecosystem doesn’t seem to make much difference in the amount of carbon stored, it does appear to have an impact on its quality and stability. Van Miegroet cautions that determining carbon quality is difficult because no standardized method of quality measurement exists. Measuring stability, however, is feasible.

“Carbon stored in soil organic matter in the conifer forest was the most unstable,” she says. “Carbon stored under the sagebrush plot appears intermediate in stability and indications are that carbon in meadows is the most stable.”

 

What’s the significance of these findings? The less stable the carbon the more readily it can return to the atmosphere as carbon dioxide or be transported to aquatic systems and throughout the food chain, says Van Miegroet. In western forests, conifers are rapidly overtaking aspen, woody species are encroaching on grasslands and native rangelands are being overtaken by invasive species. These changes, she says, will influence how soils react to changes in climate.

 

“Shrinking native ecosystems could provide further impetus for restoration of western wildlands because they’re more conducive to the storage of stable carbon,” says Van Miegroet.

 

She notes that the findings also have significance for future carbon trading on forest lands. Referring to the Chicago Climate Exchange, also known as CCX, Van Miegroet says she finds it interesting that the emissions registry and trading system currently offers below ground credits for agricultural lands only.

 

CCX resulted from efforts to improve environmental quality, which have spawned a surprising commodity: greenhouse gasses. The exchange’s carbon emissions trading system enables entities that produce a lot of carbon to meet emissions targets by buying credits from those that produce less or by supporting “offset programs” that improve the environment.

 

“As higher polluters look for offset programs, they’ll be looking for places that store carbon,” says Van Miegroet. “Wildland areas – forests and rangelands – are the place to look.”

 

Next on Van Miegroet’s agenda? “We need to find a better and quicker way to get at carbon stability,” she says. “Current methods simply take too much time. We also need to get into the biochemistry of the carbon in our varied soil samples. Technologies such as infrared spectroscopy could help us determine if there are specific vegetation signatures in our samples.”

 

 

Contact: Helga van Miegroet [helgavm@cc.usu.edu]; 435-797-3175