Volume 48 (2019): Issue 2 (June 2019)

Chamaepinnularia thermophila is a small and poorly known diatom species. After the first description from a hot spring in Guadalupe in 1952, its presence appeared to be limited to a few other springs of the French Antilles. The objective of this study is to report new information on aspects of taxonomy, distribution and ecology of this species. Accurate analysis under light and scanning electron microscope of the material collected on different substrates (cobbles, macrophytes and fine sediments) from a thermo-mineral spring of Sardinia (Italy) allowed us to document the first record of the species in the Mediterranean area. Furthermore, the comparison with Navicula tongatensis from Hustedt's original material, carried out because of their similarity, revealed identical morphological characteristics suggesting their consequent synonymy. Based on the information available in the literature and our data, C. thermophila is a rare species present mainly in tropical areas, in thermal springs with alkaline pH, medium to high conductivity and low to moderate nutrient content. The occurrence of the species at sites with very different environmental characteristics seems unusual, but it could indicate a broader ecological range. This study contributes to the standardization of the nomenclature used for this species so far and provides the first framework on its global geographic distribution and ecology.

The hydroxyproline content in Crangon crangon tissues from the Gulf of Gdansk (southern Baltic) was determined in males, non-ovigerous females and ovigerous females, depending on the individual body length, the study area (two profiles: Gdynia and Sopot) and the depth of occurrence. Individuals were collected and analyzed from April to August 2008. The research on the migratory species C. crangon indicates that the area and depth of its occurrence do not significantly affect the level of hydroxyproline in the tissues of this animal (p > 0.05). However, certain trends have been observed. Hydroxyproline participates in various life processes of C. crangon and its level in the tissues is significantly correlated with the sex of animals (p < 0.05). In males, hydroxyproline plays a major role in the body growth. Moreover, water temperature significantly affects the hydroxyproline content in males of different body sizes. Ovigerous females use hydroxyproline in the reproductive process. In non-ovigerous females, hydroxyproline participates both in the growth of organisms and in the reproductive period. Hydroxyproline can be an indicator of the collagen level, as well as an important factor in physiological processes.

Bioindication of organic pollution and seawater quality was carried out for the first time in the western part of the Sea of Azov on the basis of species composition and quantitative characteristics of microphytobenthos. A total of 229 algal samples were collected at 17 sites over the period of 2005-2014 on three different substrates in three areas under study: Sivash Gulf, the Kerch Strait and Cape Kazantip. In total, 200 taxa of algae were found, which belong to six taxonomic divisions with a predominance of diatoms. Among those, 108 taxa are indicators of substrate, water temperature, salinity, water pH, trophic state, the type of nutrition and organic pollution of water. It has been shown that the most active self-purification of water takes place in communities on stony substrates. The largest number of algae species (50%) occurs in the cleanest waters of the Kazantip Nature Reserve (Water Quality Classes I–II). The species composition of organic pollution indicators in Sivash Gulf corresponds to waters of Classes III–IV, which are more polluted than those of the Kerch Strait and Cape Kazantip. All the studied areas of the Sea of Azov are cleaner compared to some waters of the Eastern Mediterranean and the Sea of Japan.

The family of Bacillariaceae Ehrenberg is a group of well-known raphid diatoms, associated with water quality. Our current knowledge of the species diversity of this group in Turkey is still incomplete. There are three river basins in the Kütahya region in Turkey, located in the eastern part of the country, including the Gediz, Sakarya and Susurluk basins, thus the region is rich in lotic waters. We present each taxon based on our observations of specimens collected in the Kütahya region. A total of 53 sites were surveyed in this study and a total of 65 taxa from Bacillariaceae were identified. Of these 65 taxa, 15 are recognized as the first records for Turkey. For each taxon, we indicate the reference(s) used for its identification. To facilitate the identification by others working on the Turkish freshwater diatom flora, we also present dimensions of the taxa identified, the distribution of each taxon in the Kütahya region, the distribution of each taxon in Turkey as well as one or more figures for each taxon.

Mercury enters the body of seabirds in its most toxic organic form, i.e. methylmercury, mainly via the alimentary tract. Inside the body, mercury is transformed into less toxic forms and accumulates in the internal organs. The process of mercury removal from the body, most effective during the formation of new feathers and claws, is beneficial for the bird. The presented research was undertaken on account of the high affinity of mercury to keratin – a protein that forms feathers and claws – to compare the concentration levels (Hg_TOT) in these structures and to assess their contribution to the purification of the body of herring gulls (Larus argentatus) Bird feathers are the only epidermal structure that is extensively described in the literature, whereas the claws have so far been poorly researched.

The study has shown that mercury in claws is built in as effectively as in feathers, and the obtained concentrations were within a wide range of 127.2–5341.5 ng Hg_TOT g^–1 of dry weight. In addition, the concentrations of total mercury accumulated in the claws were a better reflection of Hg levels in internal organs compared to feathers.

Mollusk species associated with Cystoseira barbata were examined in the Sea of Marmara in 2012 at 14 sampling sites with a depth ranging from 0.2 to 0.5 m. A total of 18 468 specimens belonging to three classes (Polyplacophora, Gastropoda and Bivalvia) and 30 species were identified. Alvania mamillata Risso, 1826 is a new record for the marine mollusk fauna of the Sea of Marmara. The number of species at the sampling sites varied from 2 to 11 (400 cm^–2), the density ranged between 758 and 63 083 ind. m^–2, and wet weight between 0.4 and 34.3 g m^–2. Gastropoda were the richest class, represented by 22 species and 7611 individuals. The families Rissoidae, Mytilidae and Pyramidellidae were represented by the largest number of species. The most dominant mollusk species in C. barbata facies were Mytilaster minimus (Poli, 1795) (37.77%), Rissoa splendida Eichwald, 1830 (27.20%), Mytilaster lineatus (Gmelin, 1791) (18.69%) and Bittium reticulatum (da Costa, 1778) (6.89%). However, the mollusks R. splendida (86%), M. lineatus (71%), M. minimus (69%) and Steromphala adansonii (Payraudeau, 1826) (67%) were characterized by the highest values of the frequency index. Canonical correspondence analysis showed that the main factors affecting the assemblages of mollusks were the content of total nitrogen, the maximum thallus height, algal wet weight and temperature

Three ex situ pore water sampling procedures (I – rhizon samplers, II – centrifugation of sediment subsamples collected from different sediment depths without core sectioning, III – core sectioning and centrifugation of sediment sections) were compared to indicate factors that may affect concentrations of pore water constituents (ammonia and sulfides). The methods were selected and modified in such a way as to determine how the concentrations are affected by different factors related to sampling procedures, e.g. contact with atmospheric air, filtration and sediment core disturbance. They were tested on nine sediment cores collected at one site in the southern Baltic Sea. The concentration of ammonia in pore water from centrifuged sediment sections was significantly higher compared to pore water extracted by rhizons – probably due to the impact of changing pH. The factor with the greatest impact on the H₂S/HS^– concentration in the analyzed pore water was the contact with atmospheric air and/or the extrusion of sediments from a core liner. Rhizons proved to be the best option for sampling pore waters analyzed for H₂S/HS^– and NH₄⁺/NH₃. In the case of H₂S/HS^– we noticed the smallest loss of the analyzed constituents. For ammonia, the centrifugation of the whole sediment sections was likely to cause interferences in the indophenol blue method.

The operation of offshore wind turbines and electricity transmission through submarine cables over long distances generate electromagnetic or static magnetic fields (depending on the technical solution) that may modify the natural geomagnetic field and cause induced electric and electromagnetic fields in the water. The present study synthesizes the current knowledge and speculates on the possible environmental impact of electrical energy transfer based on the example of the Polish Marine Areas (southern Baltic Sea). We review the possible effects of the electrical energy induction and transfer against the existing and planned wind turbine installations. Furthermore, we consider different cable design variants as a way of environmental impact mitigation. Possible impacts of induced magnetic fields on marine organisms and, consequently, on the ecosystem functioning are also addressed.