Hydrostatic constraints on morphological exploitation of light in tall Sequoia sempervirens trees

@article{Ishii2008HydrostaticCO,
  title={Hydrostatic constraints on morphological exploitation of light in tall Sequoia sempervirens trees},
  author={Hiroaki T. Ishii and Gregory M. Jennings and Stephen C. Sillett and George W. Koch},
  journal={Oecologia},
  year={2008},
  volume={156},
  pages={751-763}
}
We studied changes in morphological and physiological characteristics of leaves and shoots along a height gradient in Sequoia sempervirens, the tallest tree species on Earth, to investigate whether morphological and physiological acclimation to the vertical light gradient was constrained by hydrostatic limitation in the upper crown. Bulk leaf water potential (Ψ) decreased linearly and light availability increased exponentially with increasing height in the crown. During the wet season, Ψ was… 

Physiological consequences of height-related morphological variation in Sequoia sempervirens foliage.

Relationships between foliar morphology and gas exchange characteristics as they vary with height within and among crowns of Sequoia sempervirens D. Don trees are examined, suggesting a transition from light to water relations as the primary determinant of morphology with increasing height.

The hydrostatic gradient, not light availability, drives height-related variation in Sequoia sempervirens (Cupressaceae) leaf anatomy.

That variation in leaf structure may be caused more by gravity than by light calls into question use of the terms "sun" and "shade" to describe leaves at the tops and bottoms of tall tree crowns.

Physiological and morphological acclimation to height in cupressoid leaves of 100-year-old Chamaecyparis obtusa

It is inferred that transfusion tissue flanking the leaf vein, which was more developed in the treetop leaves, contributes to water-stress acclimation and maintenance of leaf hydraulic conductance by facilitating osmotic adjustment of leaf water potential and efficient water transport from xylem to mesophyll.

Leaf acclimation to light availability supports rapid growth in tall Picea sitchensis trees

Anatomical investigations spanning the height gradient in tall tree crowns build the understanding of mechanisms underlying among-species variation in growth rates, life spans, and potential responses to climate change.

Hydraulic constraints modify optimal photosynthetic profiles in giant sequoia trees

It is found that leaf N and photosynthesis capacity do not follow the vertical light gradient, supporting the hypothesis that increasing limitations on water transport capacity with height modify photosynthetic optimization in tall trees.

Vertical gradients in foliar physiology of tall Picea sitchensis trees.

The use of fog, dew, and rain deposits on leaves and shifts in leaf structure to conserve and possibly enhance photosynthetic capacity likely contribute to the rapid growth rates measured in P. sitchensis trees in northwestern California.

Pushing the limits to tree height: could foliar water storage compensate for hydraulic constraints in Sequoia sempervirens?

Evidence is shown of foliar water storage as a mechanism that could partially compensate for hydraulic constraints and sustain turgor for both photosynthesis and height growth in Sequoia sempervirens, the tallest species.

Coping with gravity: the foliar water relations of giant sequoia

A collection of foliar traits allows giant sequoia to routinely, but safely, operate close to its turgor loss point, and suggests that gravity plays a major role in the water relations of Earth's largest tree species.

Investigating within-canopy variation of functional traits and cellular structure of sugar maple (Acer saccharum) leaves

Investigating the response of leaf functional traits to light availability, height, and leaf water potential in an Acer saccharum forest to tease apart the influence of light and hydraulic limitations suggests leaves acclimate.

Effects of height on treetop transpiration and stomatal conductance in coast redwood (Sequoia sempervirens).

It is confirmed that increasing tree height reduces gas exchange of treetop foliage and thereby contributes to lower carbon assimilation and height growth rates as S. sempervirens approaches maximum height.
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