Constraining the response of carbon dynamics in the terrestrial system to climate warming are crucial for improved model-based predictions.
We aim to significantly improve our knowledge of terrestrial carbon dynamics in karst environments and their response, in particular of organic carbon reservoirs deep down in the karst, to climate variability. This goal will be obtained by combining novel information on C-cycling in contemporary karst systems with information on past C-cycle dynamics from speleothems:
- Investigating C dynamics in cave environments, in particular the size and role of present-day deep organic carbon (OC) in karst systems through extensive C monitoring. This will cover regular sampling of cave air and air outside the cave, soil air, drip water, soil leachate, karst CO2, and recent cave carbonates. Additionally, organic carbon along soil profiles from above the cave will be investigated. We will perform analyses of CO2 concentrations (where applicable) as well as δ13C and 14C signature on a monthly basis during two years. Contemporaneous speleothems will be analyzed using the novel LA-AMS Laser ablation mass spectrometry … technique.
- Understanding how speleothems record surface (vegetation) and subsurface (soil, karst) C cycling to investigate the response of terrestrial ecosystems, especially of the deep OC reservoir, to past climate shifts. For this, we will perform spatially resolved 14C analyses on speleothems covering past rapid climate shifts (< 25 ka BP Mit "ka BP" sind "Tausend Jahre vor 1950" gemeint. Das "BP" steht für "before present", was in der Paläoklima-Wissenschaft als 1950 festgelegt wurde. "11.000 ka BP" bedeuted also 11 Tausend Jahre vor 1950, oder unter Verwendung unseres gewohnten Kalenders: 9050 v. Chr.).