Ecology of Extant Dinoflagellate Cysts

In this article, we will discuss Ecology of Extant Dinoflagellate Cysts. So, let’s get started.

Ecology of Extant Dinoflagellate Cysts

Like dinoflagellates, their cysts are found in all aquatic environments and occur even in regions with a seasonal sea-ice cover (e.g., Dale, 1996; Matthiessen et al., 2005; Mertens et al., 2012; Zonneveld et al., 2013). In general, diversity is highest in shallow marine settings (continental shelf and rise) and decreases toward the poles as a function of annual mean sea-surface temperature (Chen et al., 2011). Apart from changes in assemblage composition in relation to environmental gradients, cyst morphology (e.g., process morphology and length) may be affected by environmental stress such as temperature and salinity variability (Dale, 1996; Rochon et al., 2009; Jansson et al., 2014). The assemblage composition generally depends on both water mass properties and surface water circulation pattern. Application of multivariate ordination methods (canonical correspondence, detrended correspondence, and regression analysis) on regional and global data sets confirms a relationship to different physical (e.g., mean annual and seasonal surface temperature, salinity, upwelling intensity, sea-ice cover), biological (e.g., chlorophyll-a concentration, primary productivity), and chemical (e.g., phosphate, nitrate, and bottom water oxygen concentration) water mass properties. Ecological preferences are relatively well defined for a number of extant species (Zonneveld et al., 2013). The sensitivity for nutrient availability makes them ideal to identify areas of high productivity such as polynyas and upwelling regions and also of human-induced pollution and
eutrophication if these signals can be differentiated from climate change (Dale, 2009). Biogeographic distributions of assemblages on regional and hemispheric scale have been widely used to develop transfer functions (using primarily the modern analogue technique) in order to quantitatively reconstruct sea-surface temperature and salinity, seasonal extent of sea-ice cover, and primary productivity in Quaternary sediments (e.g., de Vernal and Marret, 2007; de Vernal et al., 2007; Bonnet et al., 2012).