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GLERL 2001 Milestone Reports
GOAL: SUSTAIN HEALTHY COASTS
OBJECTIVE 2: Promote Clean Coastal Water to Sustain Living Marine Resources and to Ensure Safe Recreation, Healthy Seafood, and Economic Vitality
PM: Number of coastal and Great Lake states provided with improved predictive capabilities and understanding of coastal processes.
Milestone: Single Cell Measurements of Important Phytoplankton Processes
Scientist: G. L. Fahnenstiel
Purpose: Blooms of single algal species are a common problem throughout the world. Moreover, these blooms, particularly harmful algal blooms (HABs), appear to be increasing worldwide. Because most limnological and oceanographic measurements are made on whole algal communities, they often lack the necessary discrimination to determine the causes of single species algal blooms. As part of two large NOAA programs (EEGLE and ECOHAB), we were able to develop and refine several techniques to provide critical measurements of important phytoplankton processes at the single cell level. These techniques, combined with other existing techniques, will allow us to determine the autoecology of bloom- forming algae.
Efforts: To date, we have developed three techniques to provide measurements of important phytoplankton processes at the single cell level. The first, and probably most important, is a microphotometric technique to measure light absorption characteristics of single cells. This technique will allow us to examine competitive abilities in light utilization as a mechanism contributing to bloom formation. The other two techniques relate to determining the nutrient status of phosphorus limited cells. The first one is single cell alkaline phosphatase activity, which is simply an adaptation of the popular community measurement. The second technique was the determination of poly-phosphate bodies in individual cells.
Customers: All people interested in the causes of algal blooms
Significance: Utilizing the microphotometric technique,
we were able to demonstrate that the success of diatoms during
the spring
isothermal mixed period was due in large part to their superior
light utilization. Similarly, the red-tide algae (G.
breve) appears to have a
competitive advantage for utilizing available light after the
initial development of a bloom. This competitive advantage
appears to be one of
the reasons for the persistence of red-tide blooms.
Success: To date all three techniques have been applied to autoecological studies in Lake Michigan and the Gulf of Mexico. Three papers have already been published using these techniques, and we anticipate that many more will follow.
Next Step: Besides the further development of these
three techniques, our future research is directed to integrating
these measurements with
other single cell measurements of photosynthesis and growth in
order to compare photosynthetic and growth of different species
under natural
conditions. This will allow us to determine the role of
autotrophic processes in any specific bloom.
Last updated: July 9, 2002 mbl