Can we see differences between the C activities of urban (Zagreb) and rural (Cvetković) sites (central Croatia)?

Radiocarbon (ΔC) was measured for four years (2019-2022) in Zagreb (Croatia) and in Cvetković village near Jastrebarsko (Zagreb County, Croatia) to see whether there are differences between the city site and the rural one because of the fossil fuel combustion. The δC was measured as grab samples once in a month in period December 2020-November 2022. The bomb-produced C has been globally distributed across the planet, but the combustion of fossil fuels that do not contain C causes a local effect of lowering ΔC.

Carbon isotope fractionation in karst aquatic mosses.

Radiocarbon activity (aC) and C composition (C) were measured in hygrophyte and mesophyte (land) mosses collected in the natural habitat of the Plitvice Lakes and along the Zrmanja and Krupa Rivers (typical continental and Mediterranean climates, respectively), Croatia. aC and C values of mosses, of atmospheric CO and dissolved inorganic carbon (DIC) were compared with contemporary data and with data from 30 years ago at the Plitvice Lakes when C activity of atmospheric CO was ∼30% higher. A positive correlation between aC and C was observed for all data reflecting the change of carbon isotopic composition in DIC along the water flows and in atmospheric CO regardless of the climatic regions and historic period.

Carbon isotopic composition (δ(13)C and (14)C activity) of plant samples in the vicinity of the Slovene nuclear power plant.

δ(13)C values of various plants (apples, wheat, and maize) collected in the vicinity of the Krško Nuclear Power Plant (Slovenia) during 2008 and 2009 were determined. By measuring dried samples and their carbonized counterparts we showed that no significant isotopic fractionation occurs during the carbonization phase of the sample preparation process in the laboratory. The measured δ(13)C values of the plants were used for δ(13)C correction of their measured (14)C activities.

Note on the spring region of Gacka River (Croatia).

We present the first results of a study of the Gacka River spring area, an important Croatian drinking water resource. Stable isotope data (obtained at the Stable Isotope Laboratory SILab in Rijeka) are used in combination with hydrological and meteorological data. The delta18O values give information on the mean catchment altitudes of the three main springs of Gacka River (Majerovo vrelo, Tonkovica vrelo and Pecina).

Stable isotope composition of daily and monthly precipitation in Zagreb.

Stable isotopic compositions (delta2H and delta18O) of daily precipitation collected in the period from October 2002 to March 2003 and monthly precipitation in the period from 2001 to 2003, as well as the corresponding meteorological data (temperature, amount of precipitation), all collected in Zagreb, Croatia, are presented. delta2H and delta18O values, both daily and monthly, show large variations due to large temperature variations and the different origin of the air masses. Variations are larger for daily samples than for composite monthly samples.