Biodiversity of benthic diatom flora in the coastal zone of Puck Bay (southern Baltic Sea): a case study of the Hel Peninsula

Abstract

The paper presents the results of the analysis of diatoms from surface sediments (stones, sands) and macroflora (seagrass, macroalgae) collected at 16 sampling sites located along the inner coastal zone of Puck Bay (southern Baltic Sea) along the Hel Peninsula. The main diatom species of epilithon, epipsammon and epiphyton were characterized with respect to their autecological preferences (habitat, salinity, trophic status, saprobity). Three groups of diatoms were distinguished with respect to the type of substrate based on the results of benthic flora analysis: diatoms (i) of one type of substrate, (ii) of two types and (iii) those occurring on all types of substrates. Moreover, the distribution of benthic diatom communities indicates ecological differences in the study area. Marine and brackish-water species were observed in large numbers in the coastal zone of the Outer Puck Bay, whereas freshwater flora occurred with a higher frequency in the coastal zone of the Puck Lagoon. The content of polysaprobionts and of α-mesosaprobionts indicates that the region of the Hel Tip is highly eutrophicated and very polluted. The coast in the vicinity of Kuznica is less polluted, whereas the best environmental conditions are found in the Jurata–Jastarnia region, as evidenced by the frequency of diatoms that are β-mesosaprobionts.

Distribution and bioavailability of mercury in the surface sediments of the Baltic Sea

“…It is also an important source of nutrition for consumers with flexible feeding strategy, especially in winter when availability of food is limited (Zaborska et al 2018;Ziółkowska et al 2018). In the coastal areas of the Baltic Sea, sedimentary organic matter is abundant with plankton or diatom detritus (Jędruch et al 2017;Winogradow and Pempowiak 2018;Witak et al 2020), while in the areas with the large benthic vegetation, the sediments also contained a lot of degraded vascular plants and macroalgal detritus (Jankowska et al 2018;Ziółkowska et al 2018). In the depositional areas of the Baltic Sea, such as Gdańsk Deep or Gotland Deep, the contribution of the autochthonous organic matter decreases in favour of terrestrial matter, especially in the deeper layers of the sediments (Szczepańska et al 2012;Winogradow and Pempkowiak 2018).…”

Biodiversity of the benthic diatom flora in the coastal zone of the Gulf of Gdańsk: a case study of the Gdynia–Sopot transect

“…In addition, the identified diatoms were classified with respect to their autoecological preferences, including microhabitat, salinity, trophic and saprobic status, which was completed based on OMNIDIA 6.08 software. All details of ecological groupings were presented by Witak et al (2020). In the case of some marine and brackish water species, trophic and saprobic preferences are irrelevant.…”

“…A valuable macroalga occurring along Kępa Redłowska is Zostera marina Linnaeus, which is the only species of seagrass observed in the Baltic Sea. This species is often found in the northern part of Puck Bay along the Hel Peninsula (Kruk-Dowgiałło & Opioła 2001;Witak et al 2020). Until the late 1950s, Zostera marina was an important component of the underwater meadows.…”

“…Previous studies usually focused on diatoms preserved in the sediments in different parts of the Gulf of Gdańsk. The diatom research in the coastal zone of the Gulf of Gdańsk was used to determine the degree of water organic pollution (Bogaczewicz-Adamczak et al 2001;Zgrundo & Bogaczewicz-Adamczak 2004) and to investigate diatom preferences with respect to habitat (Witak et al 2020). An important aspect of many diatom studies is to determine the degree of anthropogenic eutrophication.…”

“…The latest research on species diversity of epilithon, epipsammon and epiphyton was conducted in the inner coastal zone of the Hel Peninsula (Witak et al 2020). That study has shown that diatom taphocoenoses are represented by species that prefer one type of microhabitat: epilithon is characterized by the presence of Denticula creticola (Østrup) Lange-Bertalot & Krammer and Diatoma tenuis C. Agardh, the epipsammic community contained Catenula adhaerens and Navicula germanopolonica Witkowski & Lange-Bertalot, while epiphyton was represented by Cocconeis pediculus Ehrenberg, Gomphonema olivaceum (Hornemann) Ehrenberg and Mastogloia pumila (Grunow) Cleve.…”