Isotopic fingerprint of the middle Olt River basin, Romania

Abstract

One of the most important tributaries of the Danube River in Romania, the Olt River, was characterized in its middle catchment in terms of the isotopic composition using continuous flow-isotope ratio mass spectrometry (CF-IRMS). Throughout a period of 10 months, from November 2010 to August 2011, water samples from the Olt River and its more important tributaries were collected in order to investigate the seasonal and spatial isotope patterns of the basin waters. The results revealed a significant difference between the Olt River and its tributaries, by the fact that the Olt River waters show smaller seasonal variations in the stable isotopic composition and are more depleted in (18)O and (2)H. The waters present an overall enrichment in heavy isotopes during the warm seasons.

Using stable isotopes in tracing contaminant sources in an industrial area: A case study on the hydrological basin of the Olt River, Romania

“…The regression line associated with the basin water δ 2 H = 7.87 δ 18 O + 7.16 (R 2 = 0.691, p b 0.0001) (basin water line or BWL) was found to be close to the Local Meteoric Water Line (LMWL), but more enriched (situated on a lower slope). The results are similar with previous studies of the area (Popescu et al, 2014).…”

“…The Local Meteoric Water Line (LMWL) for the study area, δ 2 H = 7.98 δ 18 O + 9.82; R 2 = 0.975 (Popescu et al, 2014), was updated ( Fig. 2) with monthly isotopic mean data until October 2013, to δ 2 H = 8.04 δ 18 O + 9.79; R 2 = 0.982.…”

“…Current research focuses mainly on identifying pollution sources and determining the contributions of these sources (Peterson et al, 2001;Setzinger et al, 2002;Master et al, 2003;Segal-Rozenhaimer et al, 2004;Reinhardt et al, 2006;Nestler et al, 2011;Kanduc et al, 2012;Widory et al, 2013). As for isotopic investigations on the rivers in Romania, there are several published studies (Cuna et al, 2001;Costinel et al, 2009;Vremera et al, 2011;Butiuc-Keul et al, 2012), some with emphasis on the use of tritium as a tracer in the environment (Varlam et al, 2010;Faurescu et al, 2011), only few regarding the Olt River (Dinu et al, 2000;Popescu et al, 2014) and none on the subject of pollution source identification using the δ 15 N fingerprint. For this reason, the paper investigates the sources and transformations of inorganic nitrogen compounds (nitrate, nitrite and ammonium) in the middle Olt River basin, near the industrial area of Ramnicu Valcea, by applying a combination of physico-chemical and isotopic techniques, to determine if there are major industrial nitrogen releases in the environment.…”

A Fugacity Based Model for the Assessment of Pollutant Dynamic Evolution of VOCS and BTEX in the Olt River Basin (Romania)

“…As is known, concentrations to adsorbed substances are usually expressed as the amount of solute (sorbent) adsorbed per unit mass. K P is defined by units of L/kg and K SW is related to the density of sorbent ρS in l g/L (or g/cm 3 or mg/m 3 ) as follows: Fugacity (Z) for biotic phase (fish) (22) ρB equals the numerical density of water and can be ignored. It should be recalled, however, in cases where K BW is defined on a dry weight basis (not wet mass), or the concentration in specific tissues such as fat.…”

“…Starting from measured values of the investigated pollutants in environmental compartment [22][23][24][25][26] water the transfer of these hazardous pollutants in sediment, biota and air was achieved by modeling. To validate the model, also the measured values obtained for sediment samples were used, as these types of evidence have been worked as real samples in the laboratory.…”