SBIR-STTR Award

We propose to develop an active fluorometer using a contained light source for rapid measurements of primary productivity of marine phytoplankton in situ. The fluorometer can be used as a water profiling instrument on board ship, or as a self-contained device on moored or drifting buoys. The instrument will enable precise estimates of ocean primary productivity, better understanding of environmental factors limiting carbon fixation in the ocean, and calibration of airborne/satellite color ocean sensors. The instrument will stimulate Photosystem II of marine phytoplankton in the absorption band of 410-490 nm by a series of flashes. Using high energy, high repetition rate flashes, the phytoplankton fluorescence response, monitored at 685 nm, will be a function of the absorption cross section of Photosystem II, the turnover time of photosynthetic apparatus, and current photosynthetic rate underambient irradiance. We will investigate several methods of generating the excitation signal such as xenon flashlamps, blue light emitting diodes (LED's), or frequency doubled, solid-state lasers. Based on a choice of the excitation source, we will design a bench model of the fluorometer and test our experimental protocol in laboratory conditions using several species of marine phytoplankton. Successful completion of this program will lead to development of a submersible version of the fluorometer, and further efforts toward commercialization of the instrument.The proposed fluorometer, besides measuring the chlorophyll concentration, will measure primary productivity, characterize photosynthetic parameters of phytoplankton, and determine the nutrient/contamination status of a given body of water. Because of these capabilities, it will complement or replace the standard profiling fluorometer currently used on oceanographic research vessels. This type of instrument will be in high demand for EOS and NASA supported research programs as a means of providing ground truth data for algorithm development.oceanography, primary productivity, photosynthesis, fluorescenceSTATUS: Phase I Only

___(NOTE: Note: no official Abstract exists of this Phase II projects. Abstract is modified by idi from relevant Phase I data. The specific Phase II work statement and objectives may differ)___ We propose to develop an active fluorometer using a contained light source for rapid measurements of primary productivity of marine phytoplankton in situ. The fluorometer can be used as a water profiling instrument on board ship, or as a self-contained device on moored or drifting buoys. The instrument will enable precise estimates of ocean primary productivity, better understanding of environmental factors limiting carbon fixation in the ocean, and calibration of airborne/satellite color ocean sensors. The instrument will stimulate Photosystem II of marine phytoplankton in the absorption band of 410-490 nm by a series of flashes. Using high energy, high repetition rate flashes, the phytoplankton fluorescence response, monitored at 685 nm, will be a function of the absorption cross section of Photosystem II, the turnover time of photosynthetic apparatus, and current photosynthetic rate underambient irradiance. We will investigate several methods of generating the excitation signal such as xenon flashlamps, blue light emitting diodes (LED's), or frequency doubled, solid-state lasers. Based on a choice of the excitation source, we will design a bench model of the fluorometer and test our experimental protocol in laboratory conditions using several species of marine phytoplankton. Successful completion of this program will lead to development of a submersible version of the fluorometer, and further efforts toward commercialization of the instrument.The proposed fluorometer, besides measuring the chlorophyll concentration, will measure primary productivity, characterize photosynthetic parameters of phytoplankton, and determine the nutrient/contamination status of a given body of water. Because of these capabilities, it will complement or replace the standard profiling fluorometer currently used on oceanographic research vessels. This type of instrument will be in high demand for EOS and NASA supported research programs as a means of providing ground truth data for algorithm development.oceanography, primary productivity, photosynthesis, fluorescenceSTATUS: Phase I Only