Identification of biofilm composition covering lime-based materials

Abstract

This paper aims at identification of biofilms composition taken from lime and lime-cement plasters. The samples of plasters were exposed to natural weathering for more than three years to weather conditions of Prague as a representative of Central European continental climate. After biofilms sampling, they were cultivated using specific nutrient solutions and analysed using various types of microscopes. It was found, that the plasters were covered mostly by green algae (Hematococcus pluvialis, Klebsormidium sp., Trebouxiophyceae, Chlorophyceae and Chlorellaceae), cyanobacteria (Nostoc, Anabaena, Leptolyngbya, Phormidium, Plectonema, Synechococcales and Oscillatoriale), moulds (Aspergillus niger, Alternaria) and moss (Ceratodon purpureus). Possible influence of these organisms on hygrothermal behaviour of the base materials is subsequently discussed.