The aim of the study was to determine the still not completely described microbiome associated with the aquatic fern Azolla filiculoides. During the experiment, 58 microbial isolates (43 epiphytes and 15 endophytes) with different morphologies were obtained. We successfully identified 85% of microorganisms and assigned them to 9 bacterial genera: Achromobacter, Bacillus, Microbacterium, Delftia, Agrobacterium, and Alcaligenes (epiphytes) as well as Bacillus, Staphylococcus, Micrococcus, and Acinetobacter (endophytes). We also studied an A. filiculoides cyanobiont originally classified as Anabaena azollae; however, the analysis of its morphological traits suggests that this should be renamed as Trichormus azollae. Finally, the potential of the representatives of the identified microbial genera to synthesize plant growth-promoting substances such as indole-3-acetic acid (IAA), cellulase and protease enzymes, siderophores and phosphorus (P) and their potential of utilization thereof were checked. Delftia sp. AzoEpi7 was the only one from all the identified genera exhibiting the ability to synthesize all the studied growth promoters; thus, it was recommended as the most beneficial bacteria in the studied microbiome. The other three potentially advantageous isolates (Micrococcus sp. AzoEndo14, Agrobacterium sp. AzoEpi25 and Bacillus sp. AzoEndo3) displayed 5 parameters: IAA (excluding Bacillus sp. AzoEndo3), cellulase, protease, siderophores (excluding Micrococcus sp. AzoEndo14), as well as mineralization and solubilization of P (excluding Agrobacterium sp. AzoEpi25).

In recent years, there has been an increasing interest in the ecology of algal species Gonyostomum semen (Ehr.) Diesing, as it is often referred as an invasive species and a climate change indicator. Like many other flagellates, the species has the ability to active swimming, therefore it is often found unevenly distributed in the water column. Although there are several studies focused on the species vertical distribution (VD) and its diurnal changes, there is no general agreement about the causes and mechanisms of the phenomenon. In this paper, we analyzed G. semen VD in three stratified humic lakes in the new area of its spread in Central Europe, aiming to determine the common pattern of this phenomenon as well as to search any relationship with chemical and biotic factors. The results of this investigation showed that VD of the alga during the day varied among three lakes and that Gonyostomum migrated upward in the morning and downward in the afternoon, but it could stay in deep, anoxic and dark layers through most of the diurnal cycle. The analysis of chemical factors revealed that phosphate retrieval from deeper layers is probably not a key driver of the alga uneven VD and its migrations. Diurnal observations showed that three dominating zooplankton species (Asplanchna priodonta, Ceriodaphnia quadrangula, and Eudiaptomus graciloides) changed their vertical position in parallel to Gonyostomum. We have suggested in conclusions that the pattern of G. semen VD in temperate stratified lakes is not universal, but rather depends on particular lake conditions, including phosphate content and light climate. Since the zooplankton VD could play a regulating role in the alga behavior, further research in this field would be of great help in understanding this invasive alga ecology.

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Burnout is a phenomenon experienced by an increasing number of people at turning points in their careers. One of the groups exposed to burnout syndrome are academic teachers. The aim of this study was to characterize art therapy as a method to prevent burnout. Creative workshops conducted among academic teachers working at universities were analyzed. It was confirmed that creative activities with elements of art therapy have a positive effect on their emotions. The respondents experienced a sense of competence, self-worth, and unity with the group. Art therapy can become an effective method of burnout prevention.