Journal cover Journal topic
Biogeosciences An interactive open-access journal of the European Geosciences Union
Journal topic
Discussion papers
https://doi.org/10.5194/bgd-9-9711-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/bgd-9-9711-2012
© Author(s) 2012. This work is distributed under
the Creative Commons Attribution 3.0 License.

Research article 31 Jul 2012

Research article | 31 Jul 2012

Review status
This discussion paper is a preprint. A revision of the manuscript for further review has not been submitted.

Tracing biogeochemical processes and pollution sources with stable isotopes in river systems: Kamniška Bistrica, North Slovenia

T. Kanduč1, M. Šturm1, S. Žigon1, and J. McIntosh2 T. Kanduč et al.
  • 1Department of Environmental Sciences, Jožef Stefan Institute, Jamova cesta 39, Ljubljana 1000, Slovenia
  • 2University of Arizona, Department of Hydrology and Water Resources, 1133 E. James E., Rogers Way, Tucson, AZ, USA

Abstract. Biogeochemical processes were investigated in the Kamniška Bistrica River (Slovenia), which represents an ideal natural laboratory for studying pollution sources in catchments with high weathering capacity. The Kamniška Bistrica River water chemistry is dominated by HCO3, Ca2+, and Mg2+ and Ca2+/Mg2+ molar ratios indicate that calcite weathering is the major source of solutes to the river system. The Kamniška Bistrica River and its tributaries are oversaturated with respect to calcite and dolomite. pCO2 concentrations were on average up to 25 times over atmospheric values. δ18O values in river water ranged from −10.4 to −7.7‰ and plotted near the local meteoric water line, δ13CDIC values ranged from −12.7 to −2.7‰, controlled by biogeochemical processes in the catchment and within the stream; carbon dissolution is the most important biogeochemical process affecting carbon isotopes in the upstream portions of the catchment, while carbon dissolution and organic matter degradation control carbon isotope signatures downstream. Contributions of DIC from various biogeochemical processes were determined using steady state equations for different sampling seasons at the mouth of the Kamniška Bistrica River; results indicate that: (1) 1.9 to 2.2% of DIC came from exchange with atmospheric CO2, (2) 0 to 27.5% of DIC came from degradation of organic matter, (3) 25.4 to 41.5% of DIC came from dissolution of carbonates, and (4) 33 to 85% of DIC came from tributaries. δ15N values of nitrate ranged from −5.2‰ at the headwater spring to 9.8‰ in the lower reaches. Higher δ15N values in the lower reaches of the river suggest anthropogenic pollution from agricultural activity.

T. Kanduč et al.
Interactive discussion
Status: closed (peer review stopped)
Status: closed (peer review stopped)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
Interactive discussion
Status: closed (peer review stopped)
Status: closed (peer review stopped)
AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment
Printer-friendly Version - Printer-friendly version Supplement - Supplement
T. Kanduč et al.
Viewed  
Total article views: 927 (including HTML, PDF, and XML)
HTML PDF XML Total BibTeX EndNote
503 370 54 927 11 16
  • HTML: 503
  • PDF: 370
  • XML: 54
  • Total: 927
  • BibTeX: 11
  • EndNote: 16
Views and downloads (calculated since 01 Feb 2013)
Cumulative views and downloads (calculated since 01 Feb 2013)
Cited  
Saved  
Discussed  
No discussed metrics found.
Latest update: 18 Dec 2018
Publications Copernicus
Download
Citation
Share