Distribution of Taraxacum microspecies along soil property gradients in salt and brackish meadows on the Polish Baltic coast

Abstract

The vegetation of protected salt meadows along the Baltic coast is fairly well known; however, dandelions have been so far treated as a collective species. The aim of our study was to examine the microspecies diversity of the genus Taraxacum in Polish salt and brackish coastal meadows and to analyse soil property preferences of the dandelion microspecies identified. In addition, we analysed the relations between soil properties and vegetation patterns in dandelion-supporting coastal meadows (by canonical correspondence analysis). The salt and brackish meadows along the Polish Baltic coast we visited were found to support a total of 27 dandelion microspecies representing 5 sections. Analysis of vegetation patterns showed all the soil parameters (C:N ratio, organic matter content, pH, concentration of Mg, P, K, electrolytic conductivity of the saturated soil extract ECe) to explain 32.07% of the total variance in the species data. The maximum abundance of most dandelion microspecies was associated with the highest soil fertility, moderate pH values and organic matter content, and with the lowest magnesium content and soil salinity. The exceptions were T. latissimum, T. stenoglossum, T. pulchrifolium and T. lucidum the occurrence of which was related to the lowest soil fertility and the highest salinity. In addition, several microspecies (T. leptodon, T. gentile, T. haematicum, T. fusciflorum and T. balticum) were observed at moderate C:N ratios and ECe. Four other microspecies (T. infestum, T. cordatum, T. hamatum, T. sertatum) occurred at the lowest pH and organic matter content. The information obtained increases the still insufficient body of knowledge on ecological spectra of
individual dandelion microspecies, hence their potential indicator properties.