Ecological preferences of charophytes in Serbia in relation to habitat type and other aquatic macrophytes

The study presented is an attempt to explain variance in charophyte presence for the territory of Serbia by using several environmental parameters and to find a connection between certain species of charophytes and aquatic macrophytes found growing with them. Environmental parameters used were habitat type, water depth, altitude and four bioclimatic parameters extracted from the WorldClim set of global climate layers. The data used are an outcome of gathering all available literature and herbarium data on charophytes in Serbia ending with the first decade of twenty-first century, and were not systematically collected for the purpose of this study. Of 22 analyzed charophytes, 8 of them are in endangered and 4 in vulnerable IUCN threat categories for the Balkan region. The analyses performed were indicator species analysis (ISA), canonical correspondence analysis (CCA) and partial canonical correspondence analysis (pCCA). ISA distinguished four species of Charophyta as indicators of specific habitat types. Percentages of variance explained were 18.98% and 19.91% for CCA and pCCA, respectively. Depth and altitude were shown to be the most significant environmental factors explaining charophyte occurrence.