A system for measuring phytoplankton photosynthesis in a defined light field with an oxygen electrode

Abstract

A system is described for the precise continuous measurement of oxygen consumption and photo-synthetic oxygen evolution in a well defined light field with a polarographic oxygen electrode. The procedure uses a parallel light beam to irradiate samples, a relatively short pathlength and temperature regulation. Maximal sensitivity of the O 2 -mcasurement is 1.4 μmol O 2 /mV at 20°C. The O 2 -chamber and the O 2 -amplifier are presented in full detail together with a typical recorder tracing of a photosynthesis-irradiance curve.