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  • The sensitivity of reconstructed carbon dioxide concentrations to stomatal preparation methods using a leaf gas exchange model
Title: The sensitivity of reconstructed carbon dioxide concentrations to stomatal preparation methods using a leaf gas exchange model
Abstract PremiseMechanistic models using stomatal traits and leaf carbon isotope ratios to reconstruct atmospheric carbon dioxide (CO2) concentrations (ca) are important to understand the Phanerozoic paleoclimate. However, methods for preparing leaf cuticles to measure stomatal traits have not been standardized. MethodsThree people measured the stomatal density and index, guard cell length, guard cell pair width, and pore length of leaves from the sameGinkgo biloba,Quercus alba, andZingiber miogaleaves growing at known CO2levels using four preparation methods: fluorescence on cleared leaves, nail polish, dental putty on fresh leaves, and dental putty on dried leaves. ResultsThere are significant differences between trait measurements from each method. Modeledcacalculations are less sensitive to method than individual traits; however, the choice of assumed carbon isotope fractionation also impacted the accuracy of the results. DiscussionWe show that there is not a significant difference betweencaestimates made using any of the four methods. Further study is needed on the fractionation due to carboxylation of ribulose bisphosphate (RuBP) in individual plant species before use as a paleo‐CO2barometer and to refine estimates based upon widely applied taxa (e.g.,Ginkgo). Finally, we recommend that morphological measurements be made by multiple observers to reduce the effect of individual observational biases.  more » « less
Award ID(s):
1949151
PAR ID:
10655157
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley
Date Published:
Journal Name:
Applications in Plant Sciences
Volume:
13
Issue:
1
ISSN:
2168-0450
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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