A novel submersible phytoplankton fluorometer with multi-wavelength light emitting diode array as excitation source

Monitoring of different phytoplankton biomass is an important task for environmental management. Here, a novel submersible phytoplankton fluorometer which use light emitting diode (LED) array as excitation source is presented. Six LEDs of different wavelength are included in the excitation LED-array, the maximal emission wavelength are 380nm, 450nm,520nm,570nm,590nm and 610nm. By means of pulse excitation of different LED, fluorescence of Chl-a in different phytoplankton cells is collected and recorded. Comparing to excitation fluorescence spectral and using multivariate linear regression, chlorophyll-a content of different spectral group phytoplankton can be retrieved. With temperature and pressure probe, information of water temperature and depth also can be recorded. Consequently, the submersible phytoplankton fluorometer can used to measure chlorophyll-a content of different spectral groups phytoplankton in vitro and in situ. Potential application of the submersible phytoplankton fluorometer in environment monitoring is further elucidated.