2010/01/01 by Jens Fohlmeister, J Fohlmeister, Andrea Schröder‐Ritzrau +11
Earth and Planetary Sciences · #Geology and Paleoclimatology Research #Groundwater and Isotope Geochemistry #Karst Systems and Hydrogeology
paper · pdf · doi:10.1017/s0033822200056289
openalex publication_date 2010/01/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/23
14 C and δ 13 C values of C-containing species in cave drip waters are mainly controlled by the C isotope composition of karst rock and soil air, as well as by soil carbon dynamics, in particular the amount of soil CO 2 in the unsaturated soil zone and the process of calcite dissolution. Here, we investigate soil carbon dynamics by analyzing the 14 C activity and δ 13 C values of C dissolved in cave drip water. Monthly over a 2-yr period, we collected drip water from 2 drip sites, one fast and one relatively slow, within the shallow Grotta di Ernesto Cave (NE Italy). The 14 C data reveal a pronounced annual cycle. In contrast, the δ 13 C values do not show an annual pattern and only small interannual variability compared to the δ 13 C values of soil waters. The annual 14 C drip-water cycle is a function of drip-rate variability, soil moisture, and ultimately hydrology.