SPRINGS WITH CALCAREOUS TUFA IN THE VALLEY OF THE JAMNE CREEK IN GORCE

The study gives a detail characteristic of a hard water springs habitat with the communities of Cratoneurion commutati (habitat code of Nature 2000: 7220), localized within Nature 2000 protected area Ostoja Gorczanska PLH120018, in an upper part of the valley of Jamne creek. The vegetation is described along with the main habitat parameters, namely: altitude, exposition, slope gradient, insolation, type of bedrock, water flow regime and the spring outflow efficiency. The temperature, pH, electrical conductivity were measured in the field, the concentra tions of Ca and Mg in spring water were measured by Atomic Absorption Spectroscopy (AAS). The investigated headwater areas are small (0.7–80 m 2 ) and highly differentiated by the intensity of calcareous tufa precipitation and the degree of plant cover development.