Biogeochemistry of some selected Slovenian rivers (Kamniška Bistrica, Idrijca and Sava in Slovenia): insights into river water geochemistry, stable carbon isotopes and weathering material flows
AbstractReview of biogeochemical processes studied in three Slovenian rivers (River Kamniška Bistrica, River Sava in Slovenia and River Idrijca), which represent an ideal natural laboratory for studying biogeochemical processes and anthropogenic impacts in catchments with high weathering capacity is presented. The River Kamniška Bistrica, the River Sava in Slovenia and the River Idrijca water chemistry is dominated by HCO3-, Ca2+ and Mg2+, and Ca2+/Mg2+ molar ratios indicate that calcite/dolomite weathering is the major source of ions to the river System. The Kamniška Bistrica River, the River Sava and River Idrijca and its tributaries are oversaturated with respect to calcite and dolomite. pCO2 concentrations were on average up to 25 times over atmospheric values for River Kamniška Bistrica, 20 times for River Sava and 13 times over atmospheric values for River Idrijca. δ13CDIC values ranged from -12.7 to -2.7 ‰ in River Kamniška Bistrica, from -12.7 to -6.3 ‰ in River Sava in Slovenia, from -10.8 to -6.6 ‰ in River Idrijca, respectively. In all investigated rivers we found out that carbonate dissolution is the most important biogeochemical process affecting carbon isotopes in the upstream portions of the catchment, while carbonate dissolution and organic matter degradation control carbon isotope signatures downstream, except for River Idrijca where both processes contribute equally from source to outflow to River Soča.
How to Cite
Kanduč, T., Kocman, D., & Verbovšek, T. (2017). Biogeochemistry of some selected Slovenian rivers (Kamniška Bistrica, Idrijca and Sava in Slovenia): insights into river water geochemistry, stable carbon isotopes and weathering material flows. Geologija, 60(1), 9–26. https://doi.org/10.5474/geologija.2017.001