Frost drought in conifers at the alpine timberline: xylem dysfunction and adaptations.

  title={Frost drought in conifers at the alpine timberline: xylem dysfunction and adaptations.},
  author={Stefan Mayr and Uwe G Hacke and P. E. Schmid and Franziska Schwienbacher and Andreas Gruber},
  volume={87 12},
Drought stress can cause xylem embolism in trees when the water potential (psi) in the xylem falls below specific vulnerability thresholds. At the alpine timberline, frost drought is known to cause excessive winter embolism unless xylem vulnerability or transpiration is sufficiently reduced to avoid critical psi. We compared annual courses of psi and embolism in Picea abies, Pinus cembra, Pinus mugo, Larix decidua, and Juniperus communis growing at the timberline vs. low altitude. In addition… 

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