Open Top Chamber Experiments (OTC)

The Smithsonian Environmental Research Center (SERC) has established two sites for studying the impacts of elevated CO2 on plants and ecosystem processes: a wetland study on Chesapeake Bay and a scrub oak site on Merritt Island Wildlife Refuge, Cape Canaveral Florida. The Chesapeake Bay study has been in progress since 1987 while the Florida study has been operational since 1996. In these projects we are examining five main questions:

  • Does the acclimation of photosynthesis and respiration from long-term exposure to elevated atmospheric CO2 reduce or even eliminate the stimulation of ecosystem carbon assimilation?Does the interaction between water and high temperature stress with elevated CO2 effects on the plant and ecosystem water balance represent an additional mechanism for the stimulation of ecosystem carbon uptake?
  • Does the effect of elevated CO2 on nutrient cycling represent a positive or negative feedback onto CO2 -stimulated carbon accumulation?
  • Does elevated CO2 cause a shift in the allocation pattern of carbon among leaves, woody stems, fine roots, and rhizomes?
  • Does elevated CO2 stimulate an increase in carbon accumulation of soil?