WATER COLUMN STRATIFICATION, PHYTOPLANKTON DIVERSITY AND CONSEQUENCES FOR RESOURCE USE AND PRODUCTIVITY

Stratification of water columns determines the general availability of light and nutrients for phytoplankton growth. However, seasonal stratification can be affected and disturbed by aseasonal effects. Hence, disturbances of water column stratification imply disturbances for phytoplankton dynamics since it causes alterations in the relative supply of light and nutrients. According to ecological theory, the frequency of disturbance strongly affects the diversity of biological communities. Whether disturbances increase or decrease the diversity of a community depends on productivity and resource supply rate. However, this important interaction between disturbances and nutrient supply rate is seldom considered investigating effects of disturbance on plankton communities. Our experiments will result in a first data set showing how phytoplankton species diversity, resource use efficiency and carbon production are linked within stratification disturbance in a marine phytoplankton community and how ciliates and zooplankton communities are influenced by these stratification disturbances.