Water status dynamics and drought tolerance of juvenile European beech, Douglas fir and Norway spruce trees as dependent on neighborhood and nitrogen supply

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Sharath S. Paligi - , University of Göttingen (Author)
  • Jens Lichter - , University of Göttingen (Author)
  • Martyna Kotowska - , University of Göttingen, Macquarie University (Author)
  • Rebecca L. Schwutke - , University of Göttingen (Author)
  • Michela Audisio - , University of Göttingen (Author)
  • Klara Mrak - , University of Göttingen (Author)
  • Alice Penanhoat - , University of Göttingen (Author)
  • Bernhard Schuldt - , Chair of Forest Botany, TUD Dresden University of Technology (Author)
  • Dietrich Hertel - , University of Göttingen (Author)
  • Christoph Leuschner - , University of Göttingen (Author)

Abstract

To increase the resilience of forests to drought and other hazards, foresters are increasingly planting mixed stands. This requires knowledge about the drought response of tree species in pure and mixed-culture neighborhoods. In addition, drought frequently interacts with continued atmospheric nitrogen (N) deposition. To disentangle these factors for European beech, Norway spruce and Douglas fir, we conducted a replicated 3-factorial sapling growth experiment with three moisture levels, (high, medium, and low), two N levels (high and ambient), and pure and mixed-culture neighborhoods. We measured biomass, stomatal conductance (GS), shoot water potential (at predawn: PD, midday, and turgor loss point: TLP), branch xylem embolism resistance (50) and minimum epidermal conductance (Gmin). The three species differed most with respect to Gmin (10-fold higher in beech than in the conifers), hydroscape area (larger in beech), and the time elapsed to reach stomatal closure (TGS90) and TLP (TTLP; shorter in beech), while 50 and TLP were remarkably similar. Neighborhood (pure vs mixed-culture) influenced biomass production, water status and hydraulic traits, notably GS (higher in Douglas fir, but lower in spruce and beech, in mixtures than pure culture), hydraulic safety margin (smaller for beech in mixtures), and TGS90 and TTLP (shorter for spruce in mixture). High N generally increased GS, but no consistent N effects on leaf water status and hydraulic traits were detected, suggesting that neighbor identity had a larger effect on plant water relations than N availability. We conclude that both tree neighborhood and N availability modulate the drought response of beech, spruce, and Douglas fir. Species mixing can alleviate the drought stress of some species, but often by disadvantaging other species. Thus, our study suggests that stabilizing and building resilience of production forests against a drier and warmer climate may depend primarily on the right species choice; species mixing can support the agenda.

Details

Original languageEnglish
Article numbertpae044
JournalTree physiology
Volume44
Issue number5
Publication statusPublished - 1 May 2024
Peer-reviewedYes

External IDs

PubMed 38662576
ORCID /0000-0003-4738-5289/work/167217472

Keywords

Sustainable Development Goals

ASJC Scopus subject areas

Keywords

  • 3-factorial experiment, desiccation tolerance, embolism resistance, mixed forest, monoculture, turgor loss point