The concept of POSER (Plankton Observation with Simultaneous Enclosures in Rosfjorden)

Abstract
Enclosures with diameters of 0.75 and 1.0 m and depths to 40 m were used to investigate the phytoplankton spring bloom in southern Norway. Development of natural plankton populations was analyzed in parallel experiments supplemented by monocultures of the main phytoplankton species and in pollution experiments using Hg and Ekofisk oil. A brief account is presented of pre-investigations and enclosure design, and the objectives of POSER are outlined.