Application of bryophytes and lichens in the bioindicative assessment of the vertical differentiation of forest ecosystem habitat conditions on the example of windthrowns in the Kampinos National Park

Ecological indicator values (EIV) are a commonly used tool for assessing habitat conditions in various ecosystems. They are relatively rarely used for the analysis of epiphytic communities, which results from objective difficulties in the study of this group of organisms in full height gradient on settled trees. Windthrows provide a rare opportunity to fully analyse the biota diversity of epiphytic bryophytes and lichens. The aim of the study was to determine and compare the EIV variability for bryophytes and lichens in the vertical gradient, from terrestrial to different epiphytic exposures. The fieldworks were carried out on two windthrow areas in the Kampinos National Park (central Poland). A set of floristic lists was prepared within five distinguished parts of trees (trunk base, lower trunk, upper trunk, lower crown and upper crown) and three parts of their uproots (pit, bottom root plate and top root plate) for three species (oak, birch, pine). Ten individuals of each tree species were selected. The average values of five ecological indicator values (light, temperature, continentality, humidity and acidity) were calculated within the examined parts of trees and their uproots. The significance of differences between bryophyte and lichen EIV within same parts of trees and their uproots was checked using Wilcoxon paired test. The significance of differences of EIV calculated for bryophytes and lichens pulled together between distinguished tree and uproot parts were checked with Kruskal−Wallis or Mann−Whitney tests. Ordination of researched parts in terms of their EIV was carried out using NMDS method. The values of individual EIV obtained with the use of bryophytes and lichens for the examined parts of trees and their uproots differed significantly in most cases. The values of temperature and continentality in most cases were significantly higher for lichen, which may indicate the need for additional calibration of these indicators for these groups of organisms. The use of both groups of organisms in bioindication has increased the quantity and quality of available ecological information. The research confirmed the usefulness of ecological indicator values as a tool for analysing general habitat conditions in forest ecosystems