Reżim wydajności wybranych źródeł Austrii, Czech, Niemiec i Polski

The long-term characteristics of the discharge regime in European springs are not well known yet. In presenting the springs, stress should be laid on their discharge variability and seasonality. The paper presents mean monthly discharges in 86 springs from four countries: Austria, the Czech Republic, Germany and Poland, measured over a period of several years. The analyses were based on discharge variability coefficients (V R, CV) and Markham's seasonality parameters: seasonality index and time of concentration. The results were interpreted with reference to three basic types of hydrogeological outflows: in karst, fissure and porous springs. The regime of most investigated springs is complex (57% of all springs), and nival supply clearly dominates over precipitation supply (49% vs.8 %). Nival supply dominates also among the springs with simple regimes, as a culmination of the discharge in 35% of these outflows was observed in the spring months. In the karst spring, characterized by higher seasonal discharge, it occurs on average about three weeks later than in the fissure springs. The seasonality index of the porous outflows is several times lower, and the discharge concentration time occurs at the beginning of May. Seasonal spring discharge wasfound to be correlated with the spring elevation; the discharge of springs located at higher elevations is characterized by greater seasonal variability and later concentration date.