Index of Atmospheric Purity reflects the ecological conditions better than the environmental pollution in the Carpathian forests

Abstract

Abstract The Index of Atmospheric Purity (IAP) is a popular tool used for the assessment of air quality in polluted urban areas, on the basis of phytosociological data of epiphytic lichen communities. We hypothesized that this indicator could also be used in less polluted forest areas to determine the quality of ecological conditions for lichens. The aim of the present study was to verify the use of IAP method in the assessment of environmental pollution, and alternatively for the assessment of general ecological conditions in protected mountain forests of Gorce National Park (Polish Western Carpathians) based on the epiphytic lichen biota associated with Picea abies. The spatial distribution of IAP values on monitored sites in GNP was compared with: 1) spatial distribution of accumulated sulfur, nitrogen, selected heavy metals, and total heavy metals in Hypogymnia physodes thalli in 1993 and 2018 (30 sites), 2) mean ecological indicator values characterizing species requirements for light (L), substrate reaction (R) and nutrients (N), in 1993, 2013 and 2018 (33 sites). Generalized linear model and redundancy analysis were performed for disclosing most influencing factors affecting lichen communities. The study revealed a few negligible relationships between IAP values and accumulation of such elements as Ni, Mn, Cd, and Cr in both monitoring periods. Simultaneously, IAP can be useful for the identification of forest areas with a high degree of naturalness.