cu: Povezava med jamskimi minerali in termalnimi vodami bogatimi z žveplovodikom v dolini Cerne (JZ Romunija) V dolini Cerne, na jugoza�odu Romunije, je bilo v jurski� in kredni� apnenci� oblikovano več kot 100 jam. Za jame v tej regiji so izstopajoče tri značilnosti: prisotnost veliki� količin izločene sadre, veliko guana in visoka jamska temperatura. Visoko temperaturne anomalije niso značilne za običajno jamsko okolje. V določeni� jama�, v nižji� deli� doline Cerne, ponekod temperatura doseže 40ºC. Ta situacija je posledica prisotnosti termalni� vod, ki tečejo skozi jamo ali se nabirajo v bazeni� ter vroči� par, ki se dvigajo iz globin skozi razpoke. Posledica našteti� posebnosti so izjemni pogoji v jamskem okolju, ki dovoljujejo izločanje niza redki� mineralov. Ta študija predstavlja rezultate preiskav 57 vzorcev z rentgensko difrakcijo, geokemijo, Fourierjevo-transformacijsko infrardečo spektroskopijo in elektronsko mikroskopijo z namenom, da povežemo prisotnost jamski� mineralov z verjetnimi �ipogenimi speleogenetskimi procesi. Tukaj dokumentiramo prisotnost dvaindvajseti� sekundarni� jamski� mineralov, med katerimi je prisotnost apjonita in tamarugita prvič zabeležena v okolju jame razvite v apnenci�. Minerali pripadajo trem različnim združbam: s prevladujočimi sulfati (Diana Cave), s prevladujočimi fosfati (Adam S�aft), in sulfatno-fosfatno-nitratno bogata združba (Great Sălitrari Cave). Dodatna merjenja izotopov (δ34S) izvedena na sulfatni� kapniki�, so prispevala dodatne informacije o izvoru mineralov in jam. Ključne besede: jamski minerali, termalne vode, stabilni izotopi, �ipogena speleogeneza, dolina Cerne, Romunija.

ABSTRACT. In the Cerna Valley basin, located southwest of the Southern Carpathians and upstream from the confluence of Cerna with Belareca, an aquifer complex has developed. The basin is strongly influenced by hydrogeothermal phenomena, acting within two major geological structures, the Cerna Syncline and the Cerna Graben. The complex consists mainly of Jurassic and Cretaceous carbonate rocks, as well as the upper part of the Cerna Granite that is highly fractured, tectonically sunken into the graben. The geothermal investigations have shown the existence of some areas with values of the geothermal gradient falling into the 110-200ºC/km interval, and temperatures of 13.8-16ºC at the depth of 30 m. The zone with the maximal flux intensity is situated between the Băile Herculane railway station and the Crucea Ghizelei Well, an area where 24 sources (10 wells and 14 springs) are known. The geothermal anomaly is also extended to the south (Topleţ), north (Mehadia) and NE (Piatra Puşcată), a fact, which is stressed by the existence of hypothermal springs with low mineralization. The physical-chemical parameters of the sources show a strong N-S variability. At the entire thermo-mineral reservoir scale, the temperature of the water sources, the total mineralization, and the H 2 S quantity are increasing from the north to the south, and the pH and natural radioactivity are following the same trend.

The purpose of this study was to examine the sensitivity, in a field situation, of the hyporheic fauna to pollution by heavy metals and also to test the use of oxidative stress enzymes produced by this fauna as a sensitive indicator of oxidative stress generated by chemical contamination. This was done by surveying the patterns of distribution, structure, and composition of hyporheic invertebrate communities in one of the most polluted rivers in Romania. Twelve permanent sampling stations with differing water qualities were established along a 180 km transect of the Arieş River. Data on hyporheic invertebrate abundance and richness, chemistry of the surface and hyporheic water and interstitial suspended particles were analyzed via multifactorial analyses. In the downstream, more polluted stations, epigean species were less abundant and hyporheic communities, especially macrocrustaceans and oligochetes, became dominant. The higher levels of hyporheic invertebrate biodiversity in the moderately polluted stations compared to highly polluted, and the increase of the number of some hyporheos (especially macrocrustaceans) in the moderately polluted stations, suggested that the hyporheic fauna was more tolerant of heavy metal pollution than the surface water fauna of the area. However, the different richness and abundance of hyporheic fauna in sites of similar water chemistry suggested that additional factors, such as sediment structure are shaping the spatial distribution of hyporheic fauna. Strong correlations between superoxide dismutase (SOD) activity in pooled tissues extracts and some chemical parameters suggest that oxidative stress enzymes may prove to be sensitive indicators of chemical pollution in hyporheic zones.

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