Hidrológiai Közlöny 1931 (11. évfolyam)

Gedeon Tihamér: Hidrológiai megfigyelések a Vértes-hegység délkeleti részéből

128 Dr. Rezső Maucha evaporation can take place. The formation of the crust cannot be explained by slow evaporation of the water. The equilibrium of such solutions may, howewer, be very labile. As Tillmanns and Heublein stated

2 the water can only hold Ca, Mg and HCO3 ions in solution if it contains at the same time a given quantity of free CO2. This is called as equilibrium COaj Now this water contains no free CO2, thus the labile equilibrium if the dissolved calcium carbonate is disturbed on the water surface and the formation of the crust can be explained without any evaporation. If the amount of free CO2 exceeds the equilibrium amount, the excess is called aggressive CO2, since it dissolves solid lime or magnesium carbonates. Only the samples IV. and V. contained aggressive CO2. The lack of aggressive CO2 is a preliminary condition to the formation of stalagmites since waters containing aggressive CO2 dissolve calcium carbonate instead of precipitating it. For oecological and biological reasons it is important to know how much is the content on materials which are wanted to the biological process of nutriment. These consist of organic matters, further of ammonia, nitrite, nitrate, phosphate and iron. The data of my examination show that the waters of Cave Aggtelek contain very little organic matter belonging therefore to the type of oligotrophic waters. The same conclusion can be drawn of the data of the content on proteid ammonia (i. e. the N content of proteid-like matter decomposed by a treatment with potassium persulfate according to Winkler). Table I. contains the data of proteid N content. The content on proteids may be obtained by multiplying them with 6.25. The results are as follows: I. II. III. IV. V. VI. Free CO

2 Sample 0.009 0.010 0.010 0.009 0.046 4.444 grams pro liter As only about 50% of proteids is decomposed by the treatment with potassium persulfate, these numbers show about half the quantity of proteids contained by the waters. The organic matter content of the waters is smaller than that of surface eutrophic waters. Organic life is, however, possible within the Cave although the most important factor of autotrophic nutriment, the light is totally excluded. The organic matters get partly by allochthon means into the Cave, but another part of them is formed without doubt autotrophically within the Cave. The coenobia of the Cave are thus nourished partly by the Cave itself.