Long-term effects of elevated CO2 on photosynthesis and respiration are emphasized. Results confirm the large expected effects of high CO2 concentration on water carbon, and nitrogen budgets of these ecosystems. The intern will measure photosynthetic rates and bacterial growth as a function of the exposure to UV radiation. Techniques for data analysis will also be learned, including computation of growth rates from culture data and cellular light absorption from measurements of light transmitted by phytoplankton cells. Interns will present a summary of their research results at the end of the period.
Project begins in spring.
The SERC canopy project is an effort to understand the biota, environment, and ecology of the poorly known forest canopy habitat. The principal objective of this program is to understand the influence of the canopy in mediating the exchange of material and energy between the forest and the lower atmosphere, and in controlling forest microclimate and biotic habitats in vegetation. We are especially concerned with the influence of canopy structure in controlling such interactions. Other studies have focused on the forest hydrological cycle, aqueous nutrient cycling, the distribution of visible and ultraviolet light, the estimation of dry deposition to the canopy and pollutant impacts on processes of material exchange. Ongoing studies involve remote sensing of canopy internal and external structure, canopy structural changes during forest development and human modification, the sun leaf - shade leaf gradient, and the microenvironments of forest gaps.