Sinking into the Forest

Is a forest a carbon sink, sequestering more carbon dioxide (CO2) than it emits, thus improving air quality for oxygen breathing organisms?

It’s a question University of Missouri forestry professor Steven Pallardy has been exploring for the last several years at Baskett Research and Education Area near Ashland, Mo. The answer could provide insights that inform forest management and potentially impact energy and environmental policy on a continental scale.

The project, known as MOFLUX, is a collaboration that involves the MU Department Of Forestry, the Environmental Sciences Division of Oak Ridge National Laboratory and Atmospheric Turbulence and Diffusion Division of NOAA, and measures the carbon and water balance of Missouri’s oak-hickory forests on a large scale. It’s part of a network of more than 80 “Ameriflux” sites across North, Central, and South America continually monitoring fluctuations in water vapor and CO2 on an ecosystem level.

Pallardy explains the process and goals:

Nestled on the transition point of forest and prairie, known as an ecotone, and with a deciduous, multi-species, relatively undisturbed forest, researchers determined the Baskett area would be an important site for long-term study more than a decade ago.

The MOFLUX tower uses sophisticated analytical equipment to measure CO2, water vapor and meteorological information around the clock.

The “breath” of the forest, through CO2 uptake by photosynthesis and release by respiration are the key measures determining whether the forest is a sink or source of CO2.

Here Pallardy explains the annual cycles of the forest and their impacts on carbon capture:

Later this November they’ll take the research below ground, where Oak Ridge National Laboratory will install mini rhizotron cameras to monitor the growth cycle in the rhizosphere, the area surrounding roots in the soil where the biology and chemistry of the soil are influenced by the root.

How will this impact future policies and forest management? Pallardy discusses the implications here:

Steven Pallardy, MU professor of forestry, surveys the forest from atop the 100 ft. MOFLUX research tower at Baskett Research and Education Area near Ashland, Mo.
Leaves are covered in the afternoon and then measured the next day to assess the dark respiration, or respiration rates of leaves at night.
Forestry students Adam Halley and Peyton Bennett capture respiration and photosynthesis measurements throughout the canopy. Pallardy has hired students each summer to collect data at the Center. “Students learn a lot about the scientific process, about protocol, care and how instrumentation fits into scientific work and how critical it is that you operate it correctly,” Pallardy said. He and Kevin Hosman, a research specialist at Baskett, discuss the principles of the study with the students throughout the summer, emphasizing the reasons why they sample different species throughout the entire canopy.
Eight chambers monitor soil respiration at the site.
Text for audio clips available upon request.