In this section
@article{Lloyd:1995:10.1071/PP9950987,
author = {Lloyd, J and Wong, SC and Styles, JM and Batten, D and Priddle, R and Turnbull, C and Mcconchie, CA},
doi = {10.1071/PP9950987},
journal = {Australian Journal of Plant Physiology},
pages = {987--1000},
title = {Measuring and Modelling Whole-Tree Gas Exchange},
url = {http://dx.doi.org/10.1071/PP9950987},
volume = {22},
year = {1995}
}
TY - JOUR
AB - <P>Diurnal patterns of CO<sub>2</sub> and water vapour exchange were determined for <I>Macadamia integrifolia</I> and <I>Litchi chinensis</I> trees enclosed in whole-tree gas exchange chambers at Alstonville, New South Wales (28.5ºS) during October and November 1991. Whole-tree gas exchange responses to photon irradiance (I), ambient partial pressure of CO<sub>2</sub> (Ca) and vapour pressure deficit (D) were similar to those normally observed for individual leaves. Nevertheless, at a given I (above approximately 500 μmol quanta m<sup>-2</sup>, s<sup>-1</sup>) stomatal conductances (g<sub>s</sub>) and CO<sub>2</sub> assimilation rates (A) were higher under overcast, as opposed to clear sky conditions. This difference was maintained even when A and g<sub>s</sub> were examined as a function of sun angle. Combined with a simple light interception model, nested quadratic equations combining stomatal responses and biochemical characteristics of individual leaves were found to provide excellent descriptions of the gas exchange responses of the isolated trees. This indicates a close to optimal partitioning of photosynthetic machinery throughout the canopy. From the whole-tree gas exchange model it was found that higher A and g<sub>s</sub> under overcast conditions are attributable to both lower T<sub>1</sub> and D as well as to a more uniform distribution of irradiance across the canopy surface.
AU - Lloyd,J
AU - Wong,SC
AU - Styles,JM
AU - Batten,D
AU - Priddle,R
AU - Turnbull,C
AU - Mcconchie,CA
DO - 10.1071/PP9950987
EP - 1000
PY - 1995///
SP - 987
TI - Measuring and Modelling Whole-Tree Gas Exchange
T2 - Australian Journal of Plant Physiology
UR - http://dx.doi.org/10.1071/PP9950987
UR - http://www.publish.csiro.au/paper/PP9950987
VL - 22
ER -
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