Flow characteristics of intermittent rivers in Slovakia

Abstract

Abstract Flow characteristics of intermittent rivers in Slovakia. Intermittent rivers are rivers that cease to fl ow, i.e. temporary, ephemeral, seasonal, and episodic rivers. Analysis of hydrological regime of such rivers is pivotal in assessment of water resources because changes in fl ow characteristics of such rivers may affect neighboring catchments or the entire region through changes in water supply reservoirs such as lakes, wetlands and mosses. Recently, an increasing number of intermittent rivers and ephemeral streams (IRES) and an elongation of the zero- -fl ow events has been observed in Europe due to climatic changes and anthropogenic influence. Intermittent rives in Slovakia were studied in the paper using statistical methods. The characteristics of the zero-fl ow period, of duration of the longest annual zero-fl ow event and of timing of such events were derived. The circular statistics were helpful in recognition of the dates of occurrence of such events. The comparative analysis between catchments was performed. The variability in precipitation and evapotranspiration and the increasing temperature were identified as the possible drivers of the fl ow intermittence in these catchments. The research was performed within the COST Action SMIRES (Science and Management of Intermittent Rivers & Ephemeral Streams).