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The main goal of this study was to use stable carbon isotopic composition of bulk peat sampled in Tăul Mare-Bardău peat bog, Maramureş Mountains, as a tool to provide paleoclimatic information over the middle and late Holocene in this region. A peat core of 3.60 m was sampled for δ13C analysis, and bulk peat samples were analyzed by isotope ratio mass spectrometry (IRMS) method. δ13C values reveal a maximum variation of 4.69‰ along a 3.6-m-long peat core. We examined the vertical variation of δ13C bulk peat and concluded that several factors could contribute to up core trends of δ13C. Four intervals of climatic variability could be related with variations of δ13C values between ~6800 cal. yr BP and present: two wet periods (around 2800 and 545 cal. yr BP) and two dry periods (6760 and 1430 cal. yr BP). We concluded that variability in the δ13C of bulk peat profile could be influenced most heavily by the water availability, which in turn is related to the amount of precipitation at the time. Four intervals of δ13C variations of the peat sequence between 225 and 25 cm can be related with generally accepted intervals of climatic variability that have occurred within the last 2000–2500 years (‘Roman Warm Period’ (RWP), ‘Dark Age Cold Period’ (DACP), ‘Medieval Warm Period’ (MWP) and ‘Little Ice Age’ (LIA)). The climate was probably of warm–cold alternations, as revealed in our peat core by δ13C variations between 2800 cal. yr BP and present. The δ13C values of the peat profile showed two positive signals at 40 and 225 cm depth and two negative signals at 105 and 350 cm depth. We suggest that these could also represent a change in vegetation at the time.

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.

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This paper presents a study concerning the isotopic fingerprint ((18)O and (13)C) of some wines prepared from relevant Romanian grape varieties (e.g. Feteasca Alba (FA), Feteasca Regala (FR) and Cabernet Sauvignon (CS)) obtained in different vintage years (2002, 2003, 2004, 2007 and 2008). These wines were obtained from different vineyards having a significant role in the wine market: Cotesti, Tohani, Stefanesti, Aiud, Cotnari, Bucium, Murfatlar, Bujoru, Dragasani and Valea Calugareasca. Several observations related to the dependence of isotope ratios on geographical origin and climatic conditions were drawn. The authentic wines obtained from the FA grape variety from six different vineyards showed δ(18)O values in the range of+3.28 (Cotesti region - 45 °38'N/27 °04'E) to-2.60 ‰ (Aiud region - 46 °19'N/23 °45'E). The δ(13)C values were very similar for all the samples with an average of about-26 ‰. The difference between the δ(18)O values was due to the different climatic zones, which have an influence on the δ(18)O values of wine water. For the wine variety CS obtained from the Dealu Mare-Tohani vineyard, production years 2003 and 2004, a greater difference in the δ(18)O values of wine water ranging from 1.89 (in 2004) to 5.35 ‰ (in 2003) was noted. This difference is explained by the different mean annual temperatures in 2003 and 2004.