The movement of these two coastal forms can be divergent/converge

The movement of these two coastal forms can be divergent/convergent (25–35% of all cases analysed) or consistent in the onshore/offshore direction (25–40%). These observations have shown that the dynamics of the shoreline is significantly greater than that of the dune toe. The velocity of shoreline

displacement, averaged over the time between two consecutive shoreline measurements at Lubiatowo, attains respective values of about 0.4 and 0.7 m day−1 for accumulation and erosion. A more intensive shoreline retreat, well in excess of 1 m day−1, may result in the short term from high daily wave energy values. The analysis has revealed a quantity of about 50 kJ m−1, dividing shore evolution into accumulation and erosion. This value can be treated as a rough boundary for all seasons except winter, when a nearshore ice cover PD0325901 datasheet Selleckchem Epacadostat and an ice berm often form along the shoreline. The latter is a seasonal,

natural seawall protecting the beach and dune from wave impact. The shoreline in winter may therefore remain stable despite the storm events occurring in this season. Time scales are crucial in any assessment of changes to the shoreline and dune toe, as well as in analyses of the correlations between these evolutionary processes. In general, the spread of these correlations for various cross-shore profiles is smaller for long-term (25 year) observations. The stability criterion assumed for a shoreline-dune system such as the one discussed here is a beach width of 40–50 m. Of course,

DOK2 during short-lived extreme events, these values may fluctuate very considerably, sometimes by as much as 50–60%. For a typical dissipative shore such as this section of the southern Baltic coast, the destruction of dune systems implies threats to the hinterland. The climatic changes observed in recent decades, namely, global warming, can reduce the intensity and duration of winter ice phenomena, making the Baltic shores less resilient to storm attacks. The lack of a seasonal nearshore ice cover and ice berm at the shoreline, together with increased storminess, will certainly increase the vulnerability of the coast to erosion. “
“Dinoflagellates constitute the major phytoplankton group in marine environments with harmful species, causing red tides and shellfish poisonings in coastal areas (de Vernal & Marret 2007). The life cycle of many dinoflagellates consists of an asexual vegetative phase, with production by binary fission, and a sexual phase, involving reproduction by gamete fusion (Pfiester & Anderson 1987). Sexual reproduction yields a motile cell, the zygote, which can either return to the vegetative stage or become a hypnozygote, or resting cyst, which is unable to swim and sinks to the bottom sediments (Figueroa et al. 2007). Cysts can remain viable in sediments for 5–10 years or longer (Anderson et al. 1995).

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