The validity of optimal leaf traits modelled on environmental conditions.

The ratio of leaf intercellular to ambient CO2 (χ) is modulated by stomatal conductance (gs ). These quantities link carbon (C) assimilation with transpiration, and along with photosynthetic capacities (Vcmax and Jmax ) are required to model terrestrial C uptake. We use optimization criteria based on the growth environment to generate predicted values of photosynthetic and water-use efficiency traits and test these against a unique dataset. Leaf gas-exchange parameters and carbon isotope discrimination were analysed in relation to local climate across a continental network of study sites. Sun-exposed leaves of 50 species at seven sites were measured in contrasting seasons. Values of χ predicted from growth temperature and vapour pressure deficit were closely correlated to ratios derived from C isotope (δ13 C) measurements. Correlations were stronger in the growing season. Predicted values of photosynthetic traits, including carboxylation capacity (Vcmax ), derived from δ13 C, growth temperature and solar radiation, showed meaningful agreement with inferred values derived from gas-exchange measurements. Between-site differences in water-use efficiency were, however, only weakly linked to the plant's growth environment and did not show seasonal variation. These results support the general hypothesis that many key parameters required by Earth system models are adaptive and predictable from plants' growth environments.

[1]  M. Hutchinson,et al.  A continental-scale assessment of variability in leaf traits: within species, across sites and between seasons , 2018 .

[2]  Mesophyll conductance does not contribute to greater photosynthetic rate per unit nitrogen in temperate compared with tropical evergreen wet-forest tree leaves. , 2018, The New phytologist.

[3]  D. Eamus,et al.  Variation in bulk‐leaf 13C discrimination, leaf traits and water‐use efficiency–trait relationships along a continental‐scale climate gradient in Australia , 2018, Global change biology.

[4]  R. Dewar,et al.  New insights into the covariation of stomatal, mesophyll and hydraulic conductances from optimization models incorporating nonstomatal limitations to photosynthesis. , 2018, The New phytologist.

[5]  A. Arneth,et al.  How do leaf and ecosystem measures of water-use efficiency compare? , 2017, The New phytologist.

[6]  C. Peng,et al.  Towards a universal model for carbon dioxide uptake by plants , 2017, Nature Plants.

[7]  C. Peng,et al.  Photosynthetic responses to altitude: an explanation based on optimality principles. , 2017, The New phytologist.

[8]  Patrick Breheny,et al.  Visualization of Regression Models Using visreg , 2017, R J..

[9]  N. McDowell,et al.  Pragmatic hydraulic theory predicts stomatal responses to climatic water deficits. , 2016, The New phytologist.

[10]  Jeffrey P. Walker,et al.  An introduction to the Australian and New Zealand flux tower network - OzFlux , 2016 .

[11]  Stephen W Pacala,et al.  Optimal stomatal behavior with competition for water and risk of hydraulic impairment , 2016, Proceedings of the National Academy of Sciences.

[12]  Tim Wardlaw,et al.  The Australian SuperSite Network: A continental, long-term terrestrial ecosystem observatory. , 2016, The Science of the total environment.

[13]  P. Meir,et al.  A test of the 'one-point method' for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis. , 2016, The New phytologist.

[14]  S. Sjögersten,et al.  Ecosystem feedbacks from subarctic wetlands : vegetative and atmospheric CO2 controls on greenhouse gas emissions , 2016 .

[15]  Andrew J. Lowe,et al.  Leaf nitrogen from first principles: field evidence for adaptive variation with climate , 2016 .

[16]  Ashehad A. Ali,et al.  Global-scale environmental control of plant photosynthetic capacity. , 2015, Ecological applications : a publication of the Ecological Society of America.

[17]  R. Duursma.  Plantecophys - An R Package for Analysing and Modelling Leaf Gas Exchange Data , 2015, PloS one.

[18]  Joseph R. Stinziano,et al.  Non-structural carbohydrates in woody plants compared among laboratories. , 2015, Tree physiology.

[19]  I. C. Prentice,et al.  Optimal stomatal behaviour around the world , 2015 .

[20]  Susanne von Caemmerer,et al.  Temperature responses of mesophyll conductance differ greatly between species. , 2015, Plant, cell & environment.

[21]  I. Prentice,et al.  Reliable, robust and realistic: the three R's of next-generation land-surface modelling , 2014 .

[22]  G. Farquhar,et al.  Advances in measurements and models of photosynthetic carbon isotope discrimination in C3 plants. , 2014, Plant, cell & environment.

[23]  I. C. Prentice,et al.  Balancing the costs of carbon gain and water transport: testing a new theoretical framework for plant functional ecology. , 2014, Ecology letters.

[24]  Alistair Rogers,et al.  The use and misuse of Vc,max in Earth System Models , 2014, Photosynthesis Research.

[25]  N. Boulain,et al.  Carbon and water fluxes in an arid-zone acacia savanna woodland: An analyses of seasonal patterns and responses to rainfall events , 2013 .

[26]  I. Prentice,et al.  The optimal stomatal response to atmospheric CO2 concentration: Alternative solutions, alternative interpretations , 2013 .

[27]  Klaus Winter,et al.  Environmental and physiological determinants of carbon isotope discrimination in terrestrial plants. , 2013, The New phytologist.

[28]  Ian J. Wright,et al.  Impacts of trait variation through observed trait–climate relationships on performance of an Earth system model: a conceptual analysis , 2012 .

[29]  G. Farquhar,et al.  Ternary effects on the gas exchange of isotopologues of carbon dioxide. , 2012, Plant, cell & environment.

[30]  Pierre Martre,et al.  The Coordination of Leaf Photosynthesis Links C and N Fluxes in C3 Plant Species , 2012, PloS one.

[31]  U. Niinemets.  Optimization of foliage photosynthetic capacity in tree canopies: towards identifying missing constraints. , 2012, Tree physiology.

[32]  D. Tissue,et al.  Impacts of drought on leaf respiration in darkness and light in Eucalyptus saligna exposed to industrial-age atmospheric CO₂ and growth temperature. , 2011, The New phytologist.

[33]  Paolo De Angelis,et al.  Reconciling the optimal and empirical approaches to modelling stomatal conductance , 2011 .

[34]  W. Brand,et al.  Optimisation of photosynthetic carbon gain and within-canopy gradients of associated foliar traits for Amazon forest trees , 2010 .

[35]  T. Feldpausch,et al.  Co-limitation of photosynthetic capacity by nitrogen and phosphorus in West Africa woodlands. , 2010, Plant, cell & environment.

[36]  G. Katul,et al.  A stomatal optimization theory to describe the effects of atmospheric CO2 on leaf photosynthesis and transpiration. , 2010, Annals of botany.

[37]  J. Flexas,et al.  Role of mesophyll diffusion conductance in constraining potential photosynthetic productivity in the field. , 2009, Journal of experimental botany.

[38]  M. Hutchinson,et al.  Development and Testing of Canada-Wide Interpolated Spatial Models of Daily Minimum–Maximum Temperature and Precipitation for 1961–2003 , 2008 .

[39]  Jaume Flexas,et al.  Mesophyll conductance to CO2: current knowledge and future prospects. , 2008, Plant, cell & environment.

[40]  Howard Griffiths,et al.  Carbon isotopes and water use efficiency: sense and sensitivity , 2008, Oecologia.

[41]  Peter B Reich,et al.  Predicting leaf physiology from simple plant and climate attributes: a global GLOPNET analysis. , 2007, Ecological applications : a publication of the Ecological Society of America.

[42]  Jens Kattge,et al.  Temperature acclimation in a biochemical model of photosynthesis: a reanalysis of data from 36 species. , 2007, Plant, cell & environment.

[43]  P. Reich,et al.  Assessing the generality of global leaf trait relationships. , 2005, The New phytologist.

[44]  K. Kitajima,et al.  Variation in crown light utilization characteristics among tropical canopy trees. , 2004, Annals of botany.

[45]  L. Santiago,et al.  A Test of Gas Exchange Measurements on Excised Canopy Branches of Ten Tropical Tree Species , 2003, Photosynthetica (Praha).

[46]  John R. Evans,et al.  The kinetics of ribulose-1,5-bisphosphate carboxylase/oxygenase in vivo inferred from measurements of photosynthesis in leaves of transgenic tobacco , 1994, Planta.

[47]  James F. Reynolds,et al.  Coordination theory of leaf nitrogen distribution in a canopy , 1993, Oecologia.

[48]  J. Berry,et al.  A biochemical model of photosynthetic CO2 assimilation in leaves of C3 species , 1980, Planta.

[49]  Denis Loustau,et al.  Temperature response of parameters of a biochemically based model of photosynthesis. II. A review of experimental data , 2002 .

[50]  Graham D. Farquhar,et al.  Challenges and Opportunities of the Optimality Approach in Plant Ecology , 2002 .

[51]  Carl J. Bernacchi,et al.  Improved temperature response functions for models of Rubisco‐limited photosynthesis , 2001 .

[52]  L. Hutley,et al.  Dry season conditions determine wet season water use in the wet-tropical savannas of northern Australia. , 2000, Tree physiology.

[53]  D. Eamus,et al.  Optimization Theory Of Stomatal Behaviour - Ii. Stomatal Responses Of Several Tree Species Of North Australia To Changes In Light, Soil And Atmospheric Water Content And Temperature , 1999 .

[54]  John R. Evans,et al.  Photosynthetic nitrogen-use efficiency of species that differ inherently in specific leaf area , 1998, Oecologia.

[55]  J. Ehleringer,et al.  Interseasonal comparison of CO2 concentrations, isotopic composition, and carbon dynamics in an Amazonian rainforest (French Guiana) , 1997, Oecologia.

[56]  S. von Caemmerer,et al.  Carbon Dioxide Diffusion inside Leaves , 1996, Plant physiology.

[57]  E. Schulze,et al.  Relationships among Maximum Stomatal Conductance, Ecosystem Surface Conductance, Carbon Assimilation Rate, and Plant Nitrogen Nutrition: A Global Ecology Scaling Exercise , 1994 .

[58]  Stan D. Wullschleger,et al.  Biochemical Limitations to Carbon Assimilation in C3 Plants—A Retrospective Analysis of the A/Ci Curves from 109 Species , 1993 .

[59]  G. Collatz,et al.  Physiological and environmental regulation of stomatal conductance, photosynthesis and transpiration: a model that includes a laminar boundary layer , 1991 .

[60]  J. Read,et al.  Comparative studies in Nothofagus (Fagaceae). I : Leaf carbon isotope discrimination , 1991 .

[61]  J. Lloyd.  Modelling Stomatal Responses to Environment in Macadamia integrifolia , 1991 .

[62]  J. Ehleringer,et al.  Carbon Isotope Discrimination and Photosynthesis , 1989 .

[63]  Robert W. Pearcy,et al.  Plant Physiological Ecology , 1989, Springer Netherlands.

[64]  Graham D. Farquhar,et al.  On the Relationship Between Carbon Isotope Discrimination and the Intercellular Carbon Dioxide Concentration in Leaves , 1982 .

[65]  I. R. Cowan,et al.  Stomatal conductance correlates with photosynthetic capacity , 1979, Nature.

[66]  C. M. Britton,et al.  Relationships of photosynthetically active radiation and shortwave irradiance , 1976 .