Stable Isotope Ecohydrological Research of the Critical Zone

Investigations of the Earth’s critical zone, from the top of the trees down to the saturated subsurface, has revealed new understandings of the role of biota in the water cycle. Stable isotopes of water have been key for studying critical-zone science and ecohydrological processes because of their utility in quantifying and tracing fluxes across pools and subjects. Stable isotopes have revealed new understandings of the linkages between ecosystems, soils, and the storage and transport of water through the subsurface, which ultimately determines its partitioning among evaporation, transpiration, runoff and groundwater recharge fluxes. As technologies improve, modelling and analytical frameworks evolve, and our body of knowledge grows, applications of stable isotopes in critical-zone ecohydrological research have diversified.

This Research Topic is intended to showcase applications of stable isotopes in studying ecohydrological processes occurring in the critical zone. We invite all types of contributions, including commentaries, reviews, and original research. Work on any topic using stable isotopes to study the terrestrial water cycle is encouraged, including research on these example topics:
• Root water uptake
• Within-plant transport
• Surface-atmosphere interactions
• Soil water infiltration, mixing and percolation processes;
• Leaf gas exchange and water use efficiency
• Evapotranspiration partitioning
• Methodological developments.

We hope to attract work using innovative approaches, including observations, manipulations, labelling, environmental proxies, and simulation models. Last but perhaps foremost, we encourage submissions using measurements from regions and settings that are typically under-represented in environmental isotope research.