摘要

Delayed fluorescence (DF) excitation spectrometry was examined as a proxy for phytoplankton activity in comparison to pulse-amplitude-modulated (PAM) fluorometry and dissolved oxygen (DO) evolution. During several day-night cycles, the three target variables were monitored simultaneously, together with pH, temperature and photosynthetically active irradiance in an exponentially growing Chlorella population exposed to natural light conditions. It was found that during a diel cycle prompt and DF signals corresponded to each other and were negatively correlated to the light intensity, with maximum values during night and vice versa. The DF signal showed a strong linear relationship with the quantum yield of photosystem II. Our findings thus suggest that, in addition to the continuous monitoring of active chlorophyll of different taxonomical groups, DF excitation spectrometry also carries the potential to continuously monitor the quantum yields and relative electron transport rates in natural phytoplankton assemblages.

  • 出版日期2010-2