The investigation presents the assessment of species composition and structure of microbiota communities in the Otap Head Cave. Species were identified using standard approaches and cultivation methods. The abundance of algae and cyanobacteria was estimated applying the 5-point Brown-Blank scale. Biodiversity of biofouling communities was revealed. Cyanobacteria were the dominant group of phototrophs colonizing the cave wall and water streams. The most frequently documented cyanobacteria were species from genera Chroococcus, Gloeocapsa, Oscillatoria, and Phormidium. Among micromycetes prevailed Ascomycetes (genera Aspergillus, Penicillum, Trichoderma). The development of so-called lampenflora around artificial lights was not observed. The presence of sulphate-reducing and sulphur-oxidizing bacteria was detected, which possibly indicates that a small circulation of sulphur occurs in the cave at present time.

The biodiversity of the entrance zones of the Montenegro caves is barely studied, therefore the purpose of this study was to assess the biodiversity of several caves in Montenegro. The samples of phototrophs were taken from various substrates of the entrance zone of 7 caves in July 2017. A total of 87 species of phototrophs were identified, including 64 species of algae and Cyanobacteria, and 21 species of Bryophyta. Comparison of biodiversity was carried out using Jacquard and Shorygin indices. The prevalence of cyanobacteria in the algal flora and the dominance of green algae were revealed. The composition of the phototrophic communities was influenced mainly by the morphology of the entrance zones, not by the spatial proximity of the studied caves.

The authors have studied the composition of micromycetes of rocks and sediments of the Kinderlinskaya (Kinderle) Cave, which is located in the Republic of Bashkortostan. The cave is a multitiered system of galleries and gates with a length of 7900 meters. The air temperature in the cave ranges from 4 to 8 °C, and the air humidity amounts to 60-100%. The study was conducted between 2011 and 2014 and included a total of 50 sites in the cave and 80 soil samples from the surface. Sampling took place in different seasons in the cave, on the surface directly above the cave and in the water intake area of the cavity. To determine the species composition of micromycetes, use was made of a set of standard environments and extracts from cave substrates. The micromycetes were cultivated in a wide range of temperatures in order to isolate the largest number of species. A part of the inoculation seeding was carried out directly in the cave. As a result, 109 species of micromycetes were identified. All kinds of fungi detected in the surface soil were found in the cave as well. During the study, the researchers observed an increase in the number of species in the samples, which could be caused by an anthropogenic impact. It was revealed that the rudiments of micromycetes came from the surface into the cave with water currents. Species diversity of fungi is the greatest in areas rich in organic matter, including that of an anthropogenic origin. The conducted clean-up efforts did not contribute to any reduction in the diversity of micromycete species in the cave. Species with a high incidence rate in the cave, in the surface soil above the cave and in the water intake zone were all different.