INTERCALIBRATION OF PHYTOPLANKTON INVESTIGATIONS
Phytoplankton estimation and biomass determination are routine procedures in many lake monitoring i programmes, but there are often methodical difterences in the way the different investigators perform these analyses. We present here the results from a Danish inrercalibration on phytoplankton investigations in lakes. The aim was to assess the uncertainty in connection with phytoplankton investigations and to elaborate common guidelines for determination and biomass estimation. The intercalibration showed that the determination ofmost phytoplankton species was satisfactory. In most cases the determination of the genus-level was consistent while the determination of species-level varied considerably. “Complete abstract not presented.” Key words: phytoplankton, intercalibrarion, lake monitoring, biomass, blue-green algae, ultrasound, sonication.