TY - JOUR
T1 - Physiology, morphology, and ozone uptake of leaves of black cherry seedlings, saplings, and canopy trees
AU - Fredericksen, T. S.
AU - Joyce, B. J.
AU - Skelly, J. M.
AU - Steiner, K. C.
AU - Kolb, T. E.
AU - Kouterick, K. B.
AU - Savage, J. E.
AU - Snyder, K. R.
N1 - Funding Information:
Although the research described in this article has been funded wholly or in part by the US Environmental Protection Agency agreement CR82041 7-Ol -0, it has not been subjected to the Agency’s review and therefore does not necessarily reflect the views of the Agency, and no official endorsement should be inferred.
Funding Information:
This study was funded by the United States Environmental Protection Agency cooperative agreement CR82041 7-O1 -O with additional cooperation from the Pennsylvania Department of Environmental Resources, Bureau of Forestry Region No. 9, Penelec Corporation, GPU, and the Pennsylvania Conservation Corps. The authors thank Paul Augustine and Lee Warren of PDER for their support of this study. The authors also thank Jon Ferdinand, Steve Luetke, David O’Toole,
Copyright:
Copyright 2015 Elsevier B.V., All rights reserved.
PY - 1995
Y1 - 1995
N2 - Patterns of ozone uptake were related to physiological, morphological, and phenological characteristics of different-sized black cherry trees (Prunus serotina Ehrh.) at a site in central Pennsylvania. Calculated ozone uptake differed among open-grown seedlings, forest gap saplings, and canopy trees and between leaves in the upper and lower crown of saplings and canopy trees. On an instantaneous basis, seedling leaves had the greatest ozone uptake rates of all tree size classes due to greater stomatal conductance and higher concentrations of ozone in their local environment. A pattern of higher stomatal conductance of seedlings was consistent with higher incident photosynthetically-active radiation, stomatal density, and predawn xylem water potentials for seedlings relative to larger trees. However, seedlings displayed an indeterminate pattern of shoot growth, with the majority of their leaves produced after shoot growth had ceased for canopy and sapling trees. Full leaf expansion occurred by mid-June for sapling and canopy trees. Because many of their leaves were exposed to ozone for only part of the growing season, seedlings had a lower relative exposure over the course of the growing season, and subsequently lower cumulative uptake, of ozone than canopy trees and a level of uptake similar to upper canopy leaves of saplings. Visible injury symptoms were not always correlated with patterns in ozone uptake. Visible symptoms were more apparent on seedling leaves in concurrence with their high instantaneous uptake rates. However, visible injury was more prevalent on leaves in the lower versus upper crown of canopy trees and saplings, even though lower crown leaves had less ozone uptake. Lower crown leaves may be more sensitive to ozone per unit uptake than upper crown leaves because of their morphology. In addition, the lower net carbon uptake of lower crown leaves may limit repair and anti-oxidant defense processes.
AB - Patterns of ozone uptake were related to physiological, morphological, and phenological characteristics of different-sized black cherry trees (Prunus serotina Ehrh.) at a site in central Pennsylvania. Calculated ozone uptake differed among open-grown seedlings, forest gap saplings, and canopy trees and between leaves in the upper and lower crown of saplings and canopy trees. On an instantaneous basis, seedling leaves had the greatest ozone uptake rates of all tree size classes due to greater stomatal conductance and higher concentrations of ozone in their local environment. A pattern of higher stomatal conductance of seedlings was consistent with higher incident photosynthetically-active radiation, stomatal density, and predawn xylem water potentials for seedlings relative to larger trees. However, seedlings displayed an indeterminate pattern of shoot growth, with the majority of their leaves produced after shoot growth had ceased for canopy and sapling trees. Full leaf expansion occurred by mid-June for sapling and canopy trees. Because many of their leaves were exposed to ozone for only part of the growing season, seedlings had a lower relative exposure over the course of the growing season, and subsequently lower cumulative uptake, of ozone than canopy trees and a level of uptake similar to upper canopy leaves of saplings. Visible injury symptoms were not always correlated with patterns in ozone uptake. Visible symptoms were more apparent on seedling leaves in concurrence with their high instantaneous uptake rates. However, visible injury was more prevalent on leaves in the lower versus upper crown of canopy trees and saplings, even though lower crown leaves had less ozone uptake. Lower crown leaves may be more sensitive to ozone per unit uptake than upper crown leaves because of their morphology. In addition, the lower net carbon uptake of lower crown leaves may limit repair and anti-oxidant defense processes.
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U2 - 10.1016/0269-7491(94)00077-Q
DO - 10.1016/0269-7491(94)00077-Q
M3 - Article
C2 - 15091517
AN - SCOPUS:0029066537
SN - 0269-7491
VL - 89
SP - 273
EP - 283
JO - Environmental Pollution
JF - Environmental Pollution
IS - 3
ER -