As vegetation and soil jointly regulate whole-ecosystem processes, differential sensitivity and magnitude of their carbon and nitrogen responses to environmental perturbations may have implications for the functioning of tundra ecosystems. In this study, we addressed sensitivity and magnitude of short-term carbon and nitrogen responses of vascular plants, mosses, and soil to simulated goose disturbance and warming across three habitats that differ in soil moisture in a high-Arctic ecosystem in Svalbard.
Though the system’s total carbon and nitrogen contents were relatively resistant to both perturbations, the three studied ecosystem compartments still differed in their chemical responses (vascular plants > soil > mosses), and such differential sensitivity was further exacerbated by their different responses across habitats (mesic > moist > wet).
These findings highlight the potential for environmental perturbations to have small, yet differential short-term impacts on the carbon and nitrogen contents of vascular plants, mosses, and soil, both within and between tundra-habitats. They also imply that assessments of a single ecosystem compartment in a given context cannot be extrapolated to the whole ecosystem, suggesting that addressing vegetation and soil chemical responses in different habitats can advance our predictive capability of how the biogeochemistry of tundra ecosystems respond to environmental changes.
Reference: Petit Bon, M., Böhner, H., Bråthen, K. A., Ravolainen, V. T., and Jónsdóttir, I. S.. 2021. Variable responses of carbon and nitrogen contents in vegetation and soil to herbivory and warming in high-Arctic tundra. Ecosphere 12( 9):e03746. https://doi.org/10.1002/ecs2.3746
Text: Matteo Petit Bon, Czech Academy of Sciences.
Picture: Pink-footed geese after their arrival in Svalbard (Photo: Matteo Petit-Bon).