Micromycetes populating limestone and red brick surfaces of the Novodevichii Convent masonry

Qualitative and quantitative characteristics of the microscopic fungal comp lex developing on deteriorating limestone and red brick masonry of the Novo devichii Convent, Moscow, were determined. The abundance and temporal occur rence rate analyses revealed micromycete species most common in these habit ats. These species were found to share the capacity to grow under oligotrop hic and alkaline conditions. First, the stone surface can be gradually colo nized by oligotrophic fungi (mainly dark-colored ones, synthesizing melanin pigments), which are not very aggressive towards the substrate, and also b y the more aggressive Alternaria and Ulocladium, which acidify the medium. When the organic substrate is available in ample quantities, the number of fast-growing species actively producing acids (such as Penicillium, Aspergi llus, etc.) increases markedly. In laboratory experiments, these fungi were shown to develop and form spores on limestone, and the rate of limestone d egradation was calculated for conditions of optimal humidity and temperatur e and the absence of additional nutrients.