Ecological analysis of large floristic and plant-sociological datasets – opportunities and limitations

Abstract

Understanding co-occurrence and ecological affinities of plant species is essential in vegetation and landscape ecology. In a case study, we analysed distribution records with high data density of all commonly occurring tree and shrub species of Crete (Greece) with offshore islands. We present the ecological range of widespread and more range-restricted species in the Mediterranean area, visualising their affinities for macroclimate, topoclimate and geology by means of an ecological heatmap. Complete linkage classification of combined ecological spectra revealed groups of generalist species with broad ecological amplitude, groups related to zonal vegetation and chiefly dependent on elevation, and species of azonal vegetation grouped mainly by topography and substrates. Species and ecological groups with high affinity may be indicative of (a combination of) site features. Our re-evaluation of plant distribution records links plant geographical and ecological information, and thereby complements expert habitat and species assessments. Our case study provides deeper understanding of ecological patterns, and at the same time allows for comparison and extrapolation to other biomes.