Insights into agricultural influences and weathering processes from major ion patterns

Journal article


Publication Details

Author(s): van Geldern R, Schulte P, Mader M, Baier A, Barth J, Juhlke T, Lee K
Journal: Hydrological Processes
Publisher: WILEY
Publication year: 2018
Volume: 32
Journal issue: 7
Pages range: 891-903
ISSN: 0885-6087


Abstract

Karst areas and their catchments pose a great challenge for protection because fast conduit flow results in low natural attenuation of anthropogenic contaminants. Studies of the hydrochemistry of karst sources and river solutes are an important tool for securing and managing water resources. A study of the geochemical downriver evolution of the Wiesent River and its tributaries, located in a typical karst terrain, revealed unexpected downstream decreases of nitrate with maximum mean values of 30mg/L at the source to minimum values of 18mg/L near the river mouth. This trend persisted over the length of the river even though increased agricultural activities are evident in the downstream section of the catchment. This pattern is caused by fertilizer inputs via diffusive and fast conduits flow from karst lithology in the upstream area that may have reached the river's source even from beyond the hydrological catchment boundaries. Further downstream, these influences became diluted by tributary inputs that drain subcatchments dominated by claystone and sandstone lithologies that increased potassium and sulphate concentrations. Our findings indicate that bedrock geology remains the dominant control on the major ion chemistry of the Wiesent River and that agricultural influences are strongest near the headwaters despite increased land use further downstream, due to long-term storage and accumulation in karst aquifers. This feature may not be unique to the Wiesent River system, as carbonates cover significant portions of the Earth's surface and subsequent work in other river systems could establish whether such patterns are ubiquitous worldwide.


FAU Authors / FAU Editors

Baier, Alfons Dr.
Lehrstuhl für Angewandte Geologie
Barth, Johannes Prof.
Lehrstuhl für Angewandte Geologie
Juhlke, Tobias
Lehrstuhl für Angewandte Geologie
Lee, Kern Dr.
Lehrstuhl für Angewandte Geologie
Mader, Michael
Lehrstuhl für Angewandte Geologie
Schulte, Peter Dr.
Lehrstuhl für Theoretische Philosophie
van Geldern, Robert PD Dr.
Lehrstuhl für Angewandte Geologie


Additional Organisation
Geozentrum Nordbayern
Lehrstuhl für Angewandte Geologie


How to cite

APA:
van Geldern, R., Schulte, P., Mader, M., Baier, A., Barth, J., Juhlke, T., & Lee, K. (2018). Insights into agricultural influences and weathering processes from major ion patterns. Hydrological Processes, 32(7), 891-903. https://dx.doi.org/10.1002/hyp.11461

MLA:
van Geldern, Robert, et al. "Insights into agricultural influences and weathering processes from major ion patterns." Hydrological Processes 32.7 (2018): 891-903.

BibTeX: 

Last updated on 2018-10-08 at 23:09