Activity 2: Pelagic habitat: using the plankton communities to address properly the status of pelagic habitat and relevant spatio-temporal scales and pressures.

For the work in Activity 2, a suitable set of plankton assemblage data is essential to allow the development of assessment systems. There is no shortage of plankton data from water samples in the Mediterranean MSs that include also long-term series and valuable research data, although there may arise some accessibility problems. Nevertheless, the direct comparability of the data is sometimes limited by differences in sampling methods, levels of taxonomic identification and taxa enumeration methods, especially for zooplankton. 

At this Activity, the available MSs official data and other research data will be used, combined in case studies’ testing. Another advancement is offered by the use of Sentinel satellite data whose data product related to phytoplankton functional groups is worth exploring. The effort in Activity 2 will fuel the connection of the MSFD to Barcelona convention in the frame of IMAP’s Biodiversity Ecological Objective (EO1). This is referring to the state of pelagic habitat in two common indicators (Habitat distributional range and Condition of the habitat’s typical species and communities). To assure maximum consistency also with other Regional Sea Conventions (RSCs), the work done for D1C6 in HELCOM and OSPAR areas will be revised, and possible connections explored. The scope of the activity is, therefore, to explore the use of different components of the plankton assemblage (phytoplankton and zooplankton) to assess the biodiversity status, to set threshold values for those components in relation to ecologically relevant assessment areas, and to improve the coherence of GES definition for the MSFD next implementation cycle across the Mediterranean. 

The work in Activity 2 will be organized into three tasks, of which the first two will be dedicated to two main plankton groups, phytoplankton and zooplankton, while the third will serve to canalize the work from these into case studies and to merge and harmonize both plankton components towards a holistic assessment system and definition of GES. Although the work in phytoplankton and zooplankton tasks will have a very similar structure, the purpose of the two separated tasks is operative: to allow the formation of a working group of experts focused on the aspects that are peculiar for different plankton groups. Through the third task, both working groups of experts form a larger Think Tank of pelagic habitat specialists that will find the synergies between D1 and D4.