Understanding the dynamics of the terrestrial carbon cycle is essential for developing strategies to reduce atmospheric carbon dioxide concentrations and mitigate global warming. Although this topic is extensively studied, key uncertainties remain—particularly regarding the temporal dynamics of the carbon cycle and how long carbon persists in terrestrial ecosystems after assimilation. Addressing these gaps is critical for a deeper understanding of carbon cycle processes.
The temporal dimension of the carbon cycle emerges from how carbon moves through ecosystems. Carbon enters via photosynthesis and is initially allocated to fast-cycling pools, where much of it is rapidly returned to the atmosphere. Only a fraction is gradually transferred to slow-cycling soil pools, where it can persist for years to centuries. The efficiency of this transfer depends on plant allocation strategies, microbial processing, soil properties, and climate.
This session explores how carbon isotopic tracers improve our understanding of carbon accumulation, transfer, and retention over time. Stable carbon isotopes (δ¹³C) trace recent carbon assimilation and allocation (from hours to days), while radiocarbon (∆¹⁴C) provides insights into carbon age and persistence over years to centuries.
We welcome contributions that use natural and induced carbon tracers—both stable and radioactive isotopes—across in situ and laboratory experiments, as well as modeling approaches. Studies investigating carbon allocation, transfer among pools, and retention in different terrestrial pools are encouraged, including those aiming to understand the variables driving the temporal dynamics of these processes. All types of terrestrial ecosystems and spatial scales are welcome.
By bringing together recent advances in the use of carbon isotopes, this session aims to enhance understanding of the temporal dynamics of carbon in terrestrial ecosystems and identify key knowledge gaps under ongoing environmental change.