Ten years of changes in hydrology and vegetation in montane mires of temperate zone in Central Europe (Šumava National Park).

Because of their extreme environment and vulnerability, mires are well able to reflect the ongoing climate change. Northern mires are presently being studied intensively from this point of view. But little is known about the effect of climate change on peatlands in temperate zone. Monitoring of mires in sensitive montane regions of continental Europe can provide valuable information in this regard. This article uses more than 10 years of data from our monitoring to show hydrological and vegetation changes in well-preserved mountain mires. Primary attention has been paid to mire hydrology, especially the water table and its fluctuations, and vegetation, as they are among the key drivers for carbon cycling and ecological processes in peatlands. The results presented reveal a decreasing mean water table level in the studied mires, particularly in ombrotrophic bogs where their distinct microtopographic features show different responses. Minerotrophic fens well supplied by upwelling groundwater present a more hydrologically stable picture. Changes in mire vegetation were also found, the most significant shifts recorded being among wet microtopographic features related to open bog expanses (sedge hollows, lawns). For example, the cover of Warnstorfia fluitans and sedges (mainly Carex limosa) was considerably reduced. In contrast, the vegetation of hummocks (representing the drier end of the moisture gradient) proved to be relatively stable, including the species composition of Sphagnum mosses. [ABSTRACT FROM AUTHOR]