Central European pine bogs changing along an altitudinal gradient.

Vegetation analyses (phytosociological relevés) of 20 peat bogs arranged along an altitudinal gradient in the southern part of the Czech Republic, Central Europe, revealed relationships between vegetation and environmental gradients. Six of the peat bogs were investigated in detail. The bogs were dominated by Pinus rotundata, a species endemic to Central Europe, and its hybridogenous populations with P. mugo (the hybrid is called P. ×pseudopumilio), with increasing proportions of the latter at higher altitudes. Data were processed using indirect (DCA) and direct (CCA) gradient analyses. Environmental variables (depth of the water table, mean and minimum temperatures, precipitation, pH, conductivity, NH4 and PO4 concentrations, total P, but not total N nor NO3 concentration), as well as biotic characteristics of the sites, such as species composition, and growth form of the dominant pines, were closely correlated with altitude. Woody species, herbs and bryophytes responded to the altitude similarly. Results also indicated the unique characteristics of each bog.