A brief report on the international congress on Plutarch held online in September 2021.

A large sample of more than 1500 individuals of scavenging Amphipoda from fur seal carcass was studied. Six species have been identified. The two most abundant species, Abyssorchomene plebs and Waldeckia obesa, are sublittoral, necrophagous amphipods that could attack the carcass when submerged in the sea. After stranding on the beach they became an attractive food source for birds eating not only the seal tissues but also the scavenging amphipods. The species composition of the present sample as well as earlier data on Antarctic tern stomach content and baited traps taken in the same area and at the same time agreed quite well. These observations confirm the expectation that Antarctic tern feeds on necrophagous amphipods picked out from carcasses stranding on the sea shore.

This paper presents new records of stenothoids from the Scotia Arc (West Antarctic). Altogether twenty species were recorded, two of which are reported in the West Antarctic for the first time. In addition, two species are here recorded for the first time since their description. New data on distribution are supplemented by taxonomical remarks on the collected species.

Underwater steel structures require periodic maintenance. In the case of vessels, anti-corrosion works are carried out in the shipyard, where very good conditions for applying organic protective coatings can be provided. Very good surface preparation can be obtained by the use of abrasive blasting. The well-prepared metal surface is free from impurities (particularly inorganic salts). Suitable conditions for the application and renovation of coatings are also ensured (creating appropriate climatic conditions, drying the air, setting the appropriate air temperature). However, there are underwater constructions that cannot be transferred above the water level and, therefore, their conservation against corrosion can take place only under the surface of the water, which significantly hinders the execution of renovation works. In this work, protective coatings for underwater application were tested. The application of coatings on selected steel surfaces over and under the water was carried out. Physico-mechanical and electrochemical tests were carried out in order to assess the quality of the obtained corrosion protection. The possible difficulties faced when applying coatings in marine conditions were discussed.

The paper reports the study of the complexation processes in aqueous solution of α-CD and DMSO. Cyclodextrins (CDs) (sometimes called cycloamyloses) are cyclic oligosaccharides formed by glucose units interconnected by α-(1,4) linkages; α-CD is one of three the most common CDs. It consists of six glucopyranose units. The speed of ultrasonic waves has been measured by the resonance method on ResoscanTM System apparatus. Some collateral data, such as density and heat capacity of the system, have also been measured. On the basis of the experimental data the excess adiabatic compressibility was determined. The extremes of the excess adiabatic compressibility function for different mixture compositions allowed us to establish the composition of molecular complexes formed in the solution. The obtained results suggest the formation of the α-CD with DMSO inclusion complexes with chemical stoichiometric ratio value of 1:1.

The study was aimed at analyzing patterns of abundance and diversity of macrozoobenthic communities along a depth gradient in the Admiralty Bay, a semi-enclosed basin located in a rapidly changing region of the western Antarctic Peninsula. The study concerns primarily the Polychaeta and Amphipoda, the taxonomic richness and diversity of both groups being analyzed at different taxonomic levels (species, genus and family). Such an analysis, which uses a basic surrogacy measure (low taxonomic resolution) can be very useful in future monitoring programs of the Admiralty Bay. The analysis was based on 35 samples collected in the summer seasons of 1984/85 and 1985/86, with a Tvärminne sampler (within the 7–30 m depth range) and an 0.1 m2 van Veen grab (deeper areas) along a transect with the depth changing from 7 to 502 m. The total macrozoobenthos abundance was found to decrease with depth, from 1581 ± 730 ind./0.1 m2 within the 7–30 m to as few as 384 ± 145 ind./0.1 m2 at 400–500 m. The number of phyla per sample was observed to increase along the depth gradient of 7–30 to 200–300 m but was substantially reduced in the deepest sublittoral (400–500 m). The results showed large differences between amphipods and polychaetes in their respective depth-related biodiversity changes. On the other hand, the diversity metrics used (Pielou’s evenness, Shannon-Wiener index, number of species per sample, number of genera per sample, number of families per sample) at different taxonomic levels within each group produced similar patterns, demonstrating the usefulness of surrogacy in studies of Antarctic fjords.

Corrosion of water distribution system is a significant issue causing problems with quality, safety and continuity of distribution. The changes of corrosion rates of the water distribution systems in Cracow made of carbon steel were investigated by analysis of online corrosion monitoring system results. Corrosion rates were determined using the linear polarization method. The impact of rain, temperatures, conductivity, dissolved oxygen content on corrosion rate were characterized. The corrosivity of different water sources like mountain water, underground water or river water were indicated. The possible actions for reducing corrosion losses were characterized. Results show that pollution of the environment in the form of acid rain and runoff from agriculture as well as the type of the source water has significant influence on corrosion of water distribution system. Corrosion monitoring system gives possibility of controlling corrosion rate by mixing waters from different sources in the way to obtain less corrosive mixture (see Fig. 8).