U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


FACE Experiments Quantify Tree Root Turnover and Carbon Sequestration Potential of Forest Soil
Published: November 26, 2003
Posted: December 04, 2003

Stable isotopes of carbon were used as tracers at two FACE (Free-Air-CO2-Enrichment) experiments to determine rates of root turnover and the transformation of carbon in tree roots to soil organic matter in a pine and a deciduous hardwood forest, two common forest types in North America. The new and unique information comes from FACE experiments at Duke University and the Oak Ridge National Laboratory, and is published in a November 21, 2003, Science article ("Impacts of fine root turnover on forest Net Primary Production and soil carbon sequestration potential") authored by Roser Matamala (Argonne National Laboratory) and colleagues. The research illustrates variability in root turnover among different forest types. The results show that growth at elevated CO2 did not accelerate root turnover in either the deciduous hardwood forest or the pine forest. Turnover of small tree roots was found to range from 1.2 to 9 years, and small roots of the hardwood trees had the most rapid turnover. Prior to these findings, small roots of trees were thought to live no longer than a year. In addition, results of the research showed that transformation of carbon in roots to soil organic matter occurs more rapidly and in greater quantity with hardwood than pine species. The research is important when considering "natural" carbon processes for sequestering excess carbon from energy sources. The longer turnover times, for example, suggest that root production and turnover in forests have been overestimated and that sequestration of anthropogenic atmospheric carbon in forest soils may be lower than currently estimated. The understanding of mechanisms also suggests improved carbon management approaches for slowing the rise of atmospheric CO2, and partially mitigating greenhouse gas induced climate change.

Contact: Roger Dahlman, SC-74, (301) 903-4951
Topic Areas:

  • Research Area: Carbon Cycle, Nutrient Cycling
  • Research Area: Free Air CO2 Enrichment (FACE)

Division: SC-23.1 Climate and Environmental Sciences Division, BER
      (formerly SC-74 Environmental Sciences Division, OBER)

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

Aug 24, 2019
New Approach for Studying How Microbes Influence Their Environment
A diverse group of scientists suggests a common framework and targeting of known microbial processes [more...]

Aug 08, 2019
Nutrient-Hungry Peatland Microbes Reduce Carbon Loss Under Warmer Conditions
Enzyme production in peatlands reduces carbon lost to respiration under future high temperatures. [more...]

Aug 05, 2019
Amazon Forest Response to CO2 Fertilization Dependent on Plant Phosphorus Acquisition
AmazonFACE Model Intercomparison. The Science Plant growth is dependent on the availabi [more...]

Jul 29, 2019
A Slippery Slope: Soil Carbon Destabilization
Carbon gain or loss depends on the balance between competing biological, chemical, and physical reac [more...]

Jul 15, 2019
Field Evaluation of Gas Analyzers for Measuring Ecosystem Fluxes
How gas analyzer type and correction method impact measured fluxes. The Science A side- [more...]

List all highlights (possible long download time)