Marine Palynologie

dinoflagellate cyst ecology

Dinoflagellates form a main phytoplankton group in seas and oceans. They are responsible for a major part of harmful algal blooms that can have large impact on economic activities and health. Notably if the blooms are formed by species that are able to produce toxins. As part of their life cycle they can produce resting cysts that can form a seed bank in sediments. The morphology of these resting cysts is species specific and the cyst association in marine sediments reflects the upper water species composition.

This makes them an excellent tool to reconstruct past upper ocean environments at times of deposition.

But:

What is the risk of future harmful blooms if cyst of bloom forming and toxic species form a seed bank in sediments?

Which species can be used to make reconstructions of past upper ocean environments based on the cyst association of marine sediment archives

To answer these question we need detailed information about the ecology of cyst forming dinoflagellates.

We gain this information by studying the production, transport, preservation and distribution of dinoflagellate cysts in modern marine ecosystems.

For instance:

We studied the relationship between cyst production and environmental parameters such as upwelling intensity, durst input, wind speed and direction over the last 20 years in the Cape Blanc upwelling system (Roza et al., 2024)

We studied the production, transport and preservation of dinoflagellate cysts in the upwelling systems off the Iberian peninsula and Northwest Africa (Garcia-Moreiras et al., 2023, 2024)

We studied the export flux of dinoflagellate cysts in active upwelling cells and upwelling filaments of the Canary Current upwelling system (Zonneveld et al., 2022)

Cited publications

Roza, S.E.V., Versteegh, G.J.M., Pospelova, V. Zonneveld, K.A.F. (2024). Environmental control of interannual and seasonal variability in dinoflagellate cyst export flux over 18 years in the Cape Blanc upwelling region (Mauritania). Frontiers in Marine Science, 11, https://doi.org/10.3389/fmars.2024.1284425

García-Moreiras, I Hatherly, M., Zonneveld, K., Dubert, J., Nolasco, R.^,Santos, A.I.^,Oliveira, A., Moita, T., Oliveira, P.B., Magalhães, J.M._,Amorim. A. New physical and biological evidence of lateral transport affecting dinoflagellate cyst distribution in the benthic nepheloid layer along a land-sea transect off Figueira da Foz (Atlantic Iberian margin). Frontiers in Marine Science, https://doi.org/10.3389/fmars.2023.1270343.

Garcia-Moreiras, I., Amorim, A, Zonneveld, K.A.F. (2024). Transport and preservation of calcareous and organic-walled dinoflagellate cysts off Cape Blanc (NW Africa) in relation to nepheloid layers. Marine Environmental Research 199, https://doi.org/10.1016/j.marenvres.2024.106577

Zonneveld, K.A.F., Grotheer, H., Versteegh, G.J.M. (2022). Dinoflagellate cysts production, excystment and transport in the upwelling off Cape Blanc (NW Africa). Frontiers in Marine Science, 10.3389/fmars.2022.915755.