The time series of two continuously operating gas monitoring stations at Old ri ssk a and Nov y Kostel located along seismoactive faults in the epicentral area of the NW Bohemian swarm earthquakes (Czech Republic) are compared with water level fluctuations in two boreholes positioned along these faults and with gas flux variations of a mofette at the Soos mofette field at 9 km distance. The seasonal trend of the monitored CO 2 concentration with a maximum in November and a minimum in March/April is governed by groundwater temperatures, superimposed in spring by soil temperatures. CO 2 concentration variations identified at Old ri ssk a are also reflected in gas flux variations in the Soos mofette and/or water level fluctuations of two boreholes. Variations in the gas monitoring recordings of station at Nov y Kostel are also linked with variations at Old ri ssk a. In all data sets, diurnal variations generated by earth tides occur, reflecting a daily stress -fault permeability cycle. Additional stress interferes with this cycle. Significant, abrupt changes are attributed to geodynamic processes linked with seismic events, as revealed by local seismicity or by the transient of waves of a strong remote earthquake. Simultaneous variations of the gas concentrations in the Nov y Kostel area and in the gas flux in the Soos point to an interconnected hydraulic conductive fault systems present in the northern part of the Cheb Basin. Sharp falls in gas concentration, during or subsequent to, earthquake swarms may reflect fault compression associated with impeded gas migration. However, gas variations also occur in periods without seismic activity, indicating changes in fault permeability were caused by local aseismic fault movements, as revealed by events with opposite trends in the gas recordings at Old ri ssk a, Nov y Kostel and the Soos. Therefore, a mathematical approach to establish a correlation between seismicity and gas geochemical variations is not possible.
The western part of the Bohemian Massif (West-Bohemia/Vogtland region at the Czech-German border) is characterized by relatively frequent intraplate earthquake swarms and by other manifestations of present-day geodynamic activity. During the strong earthquake swarm at the turn of the years 1985 and 1986, significant changes in mineral spring parameters were observed at the spa of Františkovy Lázně. In this study, we present all available data on the mineral springs parameters, and we discuss them in terms of relations to seismic activity. Some changes in discharge were very distinct, amounting up to 40%, and had a co-seismic character. The changes in temperature were less noticeable, but preceded the beginning of the swarm by several months. Some hydrological changes persisted for nearly two years after the earthquake swarm. The character of the observed changes seems to support the hypothesis on an injection of mantle fluids, in particular of CO 2 , as the main triggering mechanism of the earthquake swarm and the main cause of discharge anomalies.
Landscape classification of Central Europe was carried out in order to define the spatial framework of environmentally homogeneous typological units. The output of such a classification would be used for further assessment of ecosystem services within the focus region. Classification was based on the cluster analysis of principal components, derived from a set of abiotic data-climatic and terrain variables and a soil database. Seven specific landscape types were defined within Central Europe. Regional distribution and environmental characteristics of particular units are described.
Since 1989 slope movements and movements of tectonic origin have been monitored in three pseudocarst localities in Polická vrchovina. Monitoring has allowed to detect more or less distinct manifestations of slope movement activity in the majority of observing points. A detailed geomorphological analysis has shown time variability of the mechanism of slope movements. Presence of movements of tectonic origin hasn't been proved.
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