Study of mineral water resources from the Eastern Carpathians using stable isotopes.

The Eastern Carpathians contain many mineral water springs that feed famous Romanian health resorts such as Borsec, Biborteni and Vatra Dornei. These waters have been used for their different therapeutic effects. In this work, mineral and spring waters from these Romanian regions were investigated by means of chemical and isotopic (deltaD and delta(18)O) analyses in order to understand the recharge mechanisms and also to determine their origins. Most of the investigated springs are of meteoric origin, having the average deuterium content of the local meteoric water. The higher (18)O content with respect to the Meteoric Water Line (MWL) indicated an exchange reaction with crystalline igneous rocks at depth and with other rocks that the water encounters on its journey back to the surface.

Effects of natural environmental factors on delta13C of lichens.

This preliminary study was designed to determine the extent to which the carbon isotope ratio in four species of lichens was influenced by such features as humidity, rainfall, radioactivity, and air quality. The sampling sites were selected to be at a great distance from any pollution. At the time of sampling, field data (temperature, relative humidity, average monthly precipitation, and radioactivity) were recorded. delta(13)C in whole lichen specimens were determined using standard mass spectrometric techniques with a standard deviation of+/-0.3 per thousand. We have found a weak but negative correlation between delta(13)C and relative humidity, and a positive correlation between delta(13)C and average monthly precipitation at the studied sites. The effects were minor, of the order of 1.5 per thousand for all the lichens. We have examined the correlation between (137)Cs activity concentration of the studied lichens and delta(13)C of these lichens, and we have suggested that fixation of radiocesium does not alter photosynthesis rate. There was a delta(13)C variation with the altitude gradient with less negative delta(13)C values at higher altitude. It is possible that this difference is caused by the ozone and occurred at the high elevations.