Download Measuring photosynthetic activity with Imaging

Measuring photosynthetic activity with Imaging-PAM
Photosynthetic organisms contain chlorophyll, a photosynthetic pigment in the
chloroplasts, absorbing photons of light to be used for photosynthetic energy. A
method to study the photosynthetic activity of photosynthetic organisms is
chlorophyll-fluorescence. This method is a sensitive technique to measure chlorophyll
fluorescence in all physiologically relevant stages in a non-destructive way. The
chlorophyll measuring technique is based on the first law of thermodynamics; the sum
of energy from photosynthetic energy conservation (photochemistry, fluorescence and
heat dissipation) must be equal to one. Both fluorescence and heat dissipation is
measured by the measuring technique and thereby information of chemical energy can
be optained.
At the division of Building materials we study biological growth on rendered façades.
Besides mould and (most) bacteria, which can not do photosynthesis, all other
organisms growing on façades are photosynthetic; algae, lichens and mosses. Algae
have for example only a positive energy balance during a few hours after sunrise.
Before that it is to dark (no photosynthesis) and after a few hours in sunlight they
dessicate (neither photosynthesis or respiration). We are therefore interested to study
variations in the photosynthetic activity for different organisms growing on different
façades on for instance on daily basis at different seasons or during night and day, and
at the same time monitoring climatic variables.
Status: Ongoing
Duration: Continous, started 2009
Financing: Fysiografiska Sällskapet i Lund.
Contact: Sanne johansson, M.Sc., Ph.D.,
Building Materials, Lund University
P.O.Box 118, SE-221 00 Lund, Sweden
Phone: +46 46 222 31 00