The Mycobiota of Library Books in Russia

Numerous studies of microorganisms isolated from the surface of cultural heritage objects, including library documents, are regularly carried out in different countries. Although the micromycete composition in each case varies, some species are constantly isolated. The structure of micromycete communities that inhabit library documents was studied in 57 cities of Russia located in seven federal districts (Northwestern, Central, Southern, Volga, Ural, Siberian, and Far Eastern). Micromycetes of 95 species from 32 genera were isolated and identified. The mycobiota of the library documents represented by Ascomycota has more than 90% of the species richness; Mucoromycota make up 3-9% and Basidiomycota, 3-4%. The Aspergillaceae family was the leading family: it accounted for 48.5-67.3% of the total species richness. In all regions, species diversity is moderate: the Shannon index ranged from 2.7 to 3.3. The Mcintosh species richness index is high everywhere (48-126), except in the Ural district (15.3). The McIntosh (0.76-0.84) and Pielow (0.80-0.91) dominance indices indicate a high level of species evenness in the mycobiota. The obtained values demonstrate the stability the document mycobiota in libraries from different regions. Significant species similarity between the districts was revealed by calculation of binary coefficients: the Jaccard coefficient was from 0.44 to 0.60; the Sørensen's qualitative measure of similarity was from 0.63 to 0.75; the quantitative similarity measure of Sørensen was from 0.44 to 0.71, and Morisita-Horn was from 0.66 to 1.0. The groups of dominant species in different regions are quite similar. The study of the ecological diversity of mycobiota on library books demonstrated the moderate diversity and the stability of the community. A high degree of similarity of taxonomic structures was established regardless of the climate conditions of the regions. Cosmopolitans characterized by high frequency of occurrence formed the major core of the library book mycobiota: Alternaria alternata, Aspergillus niger, Cladosporium cladosporioides, Mucor plumbeus, and Penicillium aurantiogriseum.