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Harvard Forest Symposium Abstract 2017

  • Title: The Long-Term Pattern of Soil Respiration Response to Soil Warming, And Consequences for Carbon Storage and Feedback to the Climate System
  • Primary Author: Jerry Melillo (Marine Biological Laboratory)
  • Additional Authors: Michael Bernard (Marine Biological Laboratory); Francis Bowles (Marine Biological Laboratory); Kristen DeAngelis (University of Massachusetts Amherst); Serita Frey (University of New Hampshire); Grace Pold (University of Massachusetts Amherst); William Werner (Marine Biological Laboratory)
  • Abstract:

    In a twenty-six year soil warming experiment in a mid-latitude hardwood forest, we documented changes in soil carbon cycling to investigate the potential consequences for the climate system. Here we show soil warming results in a four-phase pattern of soil organic matter decay and carbon dioxide fluxes to the atmosphere, with phases of substantial soil carbon loss alternating with phases of no detectable loss. Several factors combine to affect the timing and magnitude of soil carbon loss and thermal acclimation. These include depletion of microbially-accessible carbon pools, reductions in microbial biomass, a shift in microbial carbon use efficiency and changes in microbial community composition. Our results support projections of a long-term, self-reinforcing carbon feedback from mid-latitude forests to the climate system as the world warms.

  • Research Category: Forest-Atmosphere Exchange; Large Experiments and Permanent Plot Studies; Soil Carbon and Nitrogen Dynamics