Rogozin et al. (2026) Water, carbon, and light use efficiencies in an old hemiboreal coniferous forest: nine-year patterns under hydroclimatic variability

Identification

• Journal: Biogeosciences
• Year: 2026
• Date: 2026-09-07
• Authors: Svyatoslav Rogozin, Alisa Krasnova, Ülo Mander, Kaido Soosaar
• DOI: 10.5194/bg-23-6149-2026

Research Groups

• Institute of Ecology & Earth Sciences, University of Tartu, Estonia
• Estonian Environment Agency

Short Summary

This study investigates the long-term dynamics and environmental controls of water (WUE), carbon (CUE), and light use efficiencies (LUE) in an old hemiboreal coniferous forest over nine consecutive growing seasons (2016–2024). The results reveal differentiated sensitivities of ecosystem efficiencies to atmospheric drying, with CUE being the most variable metric and reflecting shifts in the balance between carbon uptake and respiratory losses.

Objective

• To quantify WUE, CUE, and LUE across nine growing seasons (2016–2024)
• To examine their daily and growing-season variations and to determine the main environmental drivers controlling these changes

Study Configuration

• Spatial Scale: Eddy covariance measurements from an old upland hemiboreal coniferous forest in southern Estonia
• Temporal Scale: Nine consecutive growing seasons (2016–2024)

Methodology and Data

• Models used: EddyPro 7.0.9 software for flux calculation, REddyProc R package for carbon flux partitioning
• Data sources: Eddy covariance measurements from the Soontaga forest research station in southern Estonia

Main Results

• WUE remained generally stable across years, with only one deviating growing season (2022) linked to intensified carbon uptake over a shorter season length
• CUE exhibited pronounced variability among growing seasons, driven primarily by changes in net ecosystem production and respiration dynamics
• LUE was remarkably stable and showed no indication of age-related decline

Contributions

• This study provides new insight into the functional stability and potential thresholds of hemiboreal coniferous forests undergoing climate change
• The results reveal differentiated sensitivities of ecosystem efficiencies to atmospheric drying, with CUE being the most variable metric and reflecting shifts in the balance between carbon uptake and respiratory losses

Funding

• This research was funded by the Estonian Research Council (grant number 9385) and the European Regional Development Fund (project number 2014-2020.4.01.15-0011).

Citation

@article{Rogozin2026Water,
  author = {Rogozin, Svyatoslav and Krasnova, Alisa and Mander, Ülo and Soosaar, Kaido},
  title = {Water, carbon, and light use efficiencies in an old hemiboreal coniferous forest: nine-year patterns under hydroclimatic variability},
  journal = {Biogeosciences},
  year = {2026},
  doi = {10.5194/bg-23-6149-2026},
  url = {https://doi.org/10.5194/bg-23-6149-2026}
}