Bioindication value of tar spot on maple trees in industrial areas: the case of Ostrava region, the Czech Republic

Abstract

Rhytisma acerinum is considered to be a bioindicator of air quality and therefore the occurrence of tar spot corresponding with the level of site pollution can be used as a tool for estimation of environmental pollution. The aim of this study was to assess the bioindication value of individual maple taxa. The research was established on fieldwork in the City of Ostrava (Czech Republic) and on the investigation of 1,247 trees. Four main habitat types were selected according to assumed (high or low) levels of air pollution and type of vegetation and land use. Different occurrence of symptoms of fungal pathogen in different categories of vegetation was found. Our analysis provides evidence that trees with lower diameter at breast height (DBH) suffered from higher infestation of tar spot. Airborne dust (PM10) was identified as the air pollutant with the significant negative effect on stroma occurrence. Our results also reveal that infestation of maple leaves was significantly affected by cultivar. Therefore the most susceptible taxa to tar spot (Acer pseudoplatanus, A. pseudoplatanus ‘Atropurpureum’, A. platanoides ‘Cleveland’, A. platanoides ‘Globosum’) can be the best candidates for monitoring air pollution.