BER launches Environmental System Science Program. Visit our new website under construction!

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

BER Research Highlights


Elevated CO2 and Extreme Drought Too Much for a Temperate Forest To Handle
Published: April 18, 2011
Posted: April 29, 2011

In 2007, an extreme drought and acute heat wave impacted ecosystems across the southeastern U.S., including a 19-year-old sweetgum (Liquidambar styraciflua L.) plantation exposed experimentally to long-term elevated or ambient CO2 treatments. Stem sap velocities (i.e., tree water use) were analyzed to assess plant response to potential interactions between CO2 and these weather extremes. Canopy conductance and net carbon assimilation were modeled based on patterns of sap velocity to estimate the indirect impacts of observed reductions in transpiration under elevated CO2on premature leaf senescence. Elevated CO2 reduced sap flow by 28% during early summer, and by up to 45% late in the drought during record-setting temperatures. Elevated CO2 reduced the capacity of leaves to exchange gases with the atmosphere (i.e., stomatal conductance) and reduced photosynthetic carbon gain. Premature leaf loss also increased rapidly during this period, and was 30% greater under elevated CO2 conditions. While elevated CO2 can reduce leaf-level water use under drought conditions, acute drought may induce excessive stomatal closure that could offset the overall productive capacity of temperate forest species during extreme weather events.

References: Warren J. M., R. J. Norby, and S. D. Wullschleger. 2011. “Elevated CO2 Enhances Leaf Senescence During Extreme Drought in a Temperate Forest,” Tree Physiology 31, 117–130. DOI: 10.1093/treephys/tpr002.

Contact: Mike Kuperberg, SC-23.1, (301) 903-3281, Daniel Stover, SC-23.1, (301) 903-0289
Topic Areas:

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

Division: SC-33.1 Earth and Environmental Sciences Division, BER

 

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

Recent Highlights

Mar 23, 2021
Molecular Connections from Plants to Fungi to Ants
Lipids transfer energy and serve as an inter-kingdom communication tool in leaf-cutter ants&rsqu [more...]

Mar 19, 2021
Microbes Use Ancient Metabolism to Cycle Phosphorus
Microbial cycling of phosphorus through reduction-oxidation reactions is older and more widespre [more...]

Feb 22, 2021
Warming Soil Means Stronger Microbe Networks
Soil warming leads to more complex, larger, and more connected networks of microbes in those soi [more...]

Jan 27, 2021
Labeling the Thale Cress Metabolites
New data pipeline identifies metabolites following heavy isotope labeling.

Analysis [more...]

Aug 31, 2020
Novel Bacterial Clade Reveals Origin of Form I Rubisco
Objectives

  • All plant biomass is sourced from the carbon-fixing enzyme Rub [more...]

List all highlights (possible long download time)