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.

Spatial and seasonal variations in the stable C isotope composition of dissolved inorganic carbon and in physico-chemical water parameters in the Plitvice Lakes system.

Plitvice Lakes waters were collected at 14 sampling points, including springs, tributaries and lakes, for the period 2002-2007. The results of the physical and chemical conditions of calcite precipitation as well as the δ(13)C values of dissolved inorganic carbon (DIC) were used to study the processes influencing calcite precipitation. Significant differences between spring, lake and stream waters as well as changes in the downstream direction were observed.

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.

Distribution of hydrogen, oxygen and carbon isotopes in the atmosphere of Croatia and Slovenia.

Monitoring of isotope distribution in the atmosphere included isotopes 2H, 3H and 18O in precipitation, and 13C and 14C in atmospheric CO2. This paper presents the results of atmospheric monitoring over Croatia and Slovenia overt the last few years. Monthly precipitations in Zagreb and Ljubljana had been collected since 1976 and 1981, respectively.