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Dr. Bill BauerleEcophysiology and Plant Stress Physiology

213 Shepardson
970-491-4088 office





Research Interests:

I am interested in physiological characteristics of woody plants that ameliorate the effects of drought and thermal stress – two climate change factors that could alter the biodiversity of the U.S. terrestrial ecosystem over the course of this century. I take into account secondary stresses such as elevated temperature, because multiple stresses interact to alter plant carbon and water exchange. I work from the whole-plant level down to the molecular level in order to investigate genetic variation and quantify genotype specific drought and heat tolerance strategies. The results of this work are multifaceted: 1) to learn how physiological processes are integrated into water use and growth responses, 2) to explain the mechanisms by which multiple water stress interactions influence long-lived perennials, and 3) to predict the intrinsic physiological responses of woody perennials to water deficit.

I draw on the results of my water stress physiology research program to develop spatially explicit physiologically- and genetically-constrained models. Process modeling allows me to scale the research findings from the molecular to the ecosystem level. The biologically based modeling is an integrated component of my research program where the focus of the effort is on water and thermal abiotic stress and their respective interactions. Thus, by linking genetic predisposition with mechanistic models, I quantify ecosystem-atmosphere energy exchange and net primary production at the intraspecific level. The technique is well suited to confront the challenges in predicting the effect of water stress on genetically diverse managed landscape tree species, ecotypes, and genotypes.


Courses I Teach:

HORT 476 – Environmental Plant Stress Physiology

HORT 576 – Advanced Environmental  Plant Stress Physiology


Curriculum Vitae

Dr. Bauerle's Publications

Stinziano, J.R., W.L. Bauerle, and D.A. Way. 2019. Modelled net carbon gain responses to climate change in boreal trees: Impacts of photosynthetic parameter selection and acclimation. Global Change Biology,


Miner G.L. and W.L. Bauerle 2019. Seasonal responses of photosynthetic parameters in maize and sunflower and their relationship with leaf functional traits. Plant, Cell and Environment,


Stinziano J.R., D.A. Way, and W.L. Bauerle. 2018. Improving models of photosynthetic thermal acclimation: which parameters are most important and how many should be modified? Global Change Biology, 24, 1580-1598.


Sanow J.E., S.R. Fassnacht, D.J. Kamin, G,.A. Sexstone, W.L. Bauerle, and I. Oprea. 2018. Geometric versus anemometric surface roughness for a shallow accumulating snowpack. Geosciences, 8(12), 463.


Cavaleri, M.A., A.P. Coble, M.G. Ryan, W.L. Bauerle, H.W. Loescher, and S.F. Oberbauer. 2017. Tropical rainforest carbon sink declines during El Niño as a result of reduced photosynthesis and increased respiration rates. New Phytologist, 216:136–149. DOI: 10.1111/nph.14724


Miner, G.L. and W.L. Bauerle. 2017. Seasonal variability of the parameters of the Ball–Berry model of stomatal conductance in maize (Zea mays L.) and sunflower (Helianthus annuus L.) under well-watered and water-stressed conditions. Plant, Cell & Environment, 40:1874–1886. DOI: 10.1111/pce.12990


Hu, H., G.G. Wang, W.L. Bauerle, R.J. Klos. 2017. Drought impact on forest regeneration in the Southeast USA. Ecosphere, 8(4): e01772. 10.1002/ecs2.1772


Miner, G.L., W.L. Bauerle and D.D. Baldocchi. 2017. Estimating the sensitivity of stomatal conductance to photosynthesis: a review. Plant, Cell & Environment, 40:1214–1238. DOI: 10.1111/pce.12871


Barnard, D.M. and W.L. Bauerle. 2016. Seasonal variation in canopy aerodynamics and the sensitivity of transpiration estimates to wind velocity in broadleaved deciduous species. Journal of Hydrometeorology,


Becker, S.R., P.F. Byrne. S.D. Reid, W.L. Bauerle, J.K. McKay, S.D. Haley. 2016. Root traits contributing to drought tolerance of synthetic hexaploid wheat in a greenhouse study. Euphytica, 207:213-224.


Ali A.A., C. Xu, A. Rogers, N.G. McDowell, B.E. Medlyn, R.A. Fisher, S.D. Wullschleger, P.B. Reich, J.A. Vrugt, W.L. Bauerle, L.S. Santiago, and C.J. Wilson. 2015. Global scale environmental control of plant photosynthetic capacity. Ecological Applications, 25:2349-2365.


Barnard D.M. and W.L. Bauerle. 2015. Species-specific irrigation scheduling with a spatially explicit biophysical model: A comparison to substrate moisture sensing with insight into simplified physiological parameterization. Agricultural and Forest Meteorology, 214-215:48-59.


Reuning G.A., W.L. Bauerle, J.L. Mullen, J.K. McKay. 2015. Combining quantitative trait loci analysis with physiological models to predict genotype specific transpiration rates. Plant, Cell and Environment, 38:710-717.


Bauerle, W.L., A.B. Daniels, and D.M. Barnard. 2014. Carbon and water flux responses to physiology by environment interactions: A sensitivity analysis of variation in climate on photosynthetic and stomatal parameters. Climate Dynamics, 42:2539-2554.


Stoy, P.C., A.M. Trowbridge, and W.L. Bauerle. 2014. Controls on seasonal patterns of maximum ecosystem carbon uptake and canopy-scale photosynthetic light response: contributions from both temperature and photoperiod. Photosynthesis Research, 119: 49-64.


Lea-Cox, J.D., W.L. Bauerle, M.W. van Iersel, G.F. Kantor, T.L. Bauerle, E. Lichtenberg, D.M. King, and L. Crawford. 2013. Advancing wireless sensor networks for irrigation management of ornamental crops: An overview. HortTechnology, 23:717-724.


Bauerle, T.L. W.L. Bauerle, M. Goebel, and D.M. Barnard. 2013. Root system distribution influences substrate moisture measurements in containerized ornamental tree species HortTechnology, 23:754-759.


Fletcher, R.S., J.L. Mullen, S. Yoder, W.L Bauerle, G. Reuning, S. Sen, E. Meyer, T.E. Juenger, and J.K. McKay. 2013. Development of a next-generation NIL library in Arabidopsis thaliana for dissecting complex traits. BMC Genomics,14:655.


Barnard, D.M. and W.L. Bauerle. 2013. The implications of minimum stomatal conductance on modeling water flux in forest canopies. Journal of Geophysical Research: Biogeosciences, 118, 1322-1333. DOI 10.1002/jgrg.20112.


Gspaltl, M., W.L. Bauerle, D. Binkley, and H. Sterba. 2013. Leaf area and light use efficiency patterns of Norway spruce under different thinning regimes and age classes. Forest Ecology and Management, 288:49-59. pdf

Campoe, O., J.L. Stape, Y. Nouvello, J-P., W.L. Bauerle, D. Binkley, and G. Le Maire. 2013. Stem production, light absorption and light use efficiency between dominant and non-dominant trees of Eucalyptus grandis across a productivity gradient in Brazil. Forest Ecology and Management, 288:14-20. pdf

Bauerle, W.L., R. Oren, D.A. Way, S.S. Qian, P.C. Stoy, P.E. Thornton, J.D. Bowden, F.M. Hoffman, and R.F. Reynolds. 2012. Photoperiodic regulation of the seasonal pattern of photosynthetic capacity and the implications for carbon cycling. Proceedings of the National Academy of Sciences of the United States of America, 109:8612-8617. pdf

Daniels, A.B., D.M. Barnard, P.L. Chapman, and W.L. Bauerle. 2012. Optimizing substrate moisture measurements in containerized nurseries. HortScience, 47:98-104. pdf

Bauerle, T.L., M. Centinari, and W.L. Bauerle. 2011. Shifts in xylem vessel diameter and embolisms in grafted apple trees of differing rootstock growth potential in response to drought. Planta, 234:1045-1054. pdf

Bauerle, W.L. and J.D. Bowden. 2011. Separating foliar physiology from morphology reveals the relative roles of vertically structured transpiration factors within red maple crowns and limitations of larger scale models. Journal of Experimental Botany, 62:4295-4307. pdf

Bauerle, W.L. and J.D. Bowden. 2011. Predicting transpiration response to climate change: Insights on physiological and morphological interactions that modulate water exchange from leaves to canopies. HortScience, 46:163-166. pdf

Lea-Cox, J.D., C. Zhao, D.S. Ross, T.E. Bilderback, J.R. Harris, S.D. Day, C.X. Hong, T.H. Yeager, R.C. Beeson, W.L. Bauerle, A.G. Ristvey, M. Lorscheider, S. Dickinson, J.M. Ruter. 2010. A nursery and greenhouse online knowledge center: Learning opportunities for sustainable practice. HortTechnology, 20:509-517. pdf

Binkley, D., J.L. Stape, W.L. Bauerle, and M.G. Ryan. 2010. Explaining growth of individual trees: Light interception and efficiency of light use by Eucalyptus at four sites in Brazil. Forest Ecology and Management, 259:1704-1713. pdf

Bauerle, W.L., J.D. Bowden, G.G. Wang, and M.A. Shahba. 2009. Exploring the importance of within-canopy spatial temperature variation on transpiration predictions. Journal of Experimental Botany, 60:3665-3676. pdf

Reynolds, R.F., W.L. Bauerle, and Y. Wang. 2009. Simulating carbon dioxide exchange rates of deciduous tree species: evidence for a general pattern in biochemical changes and water stress response. Annals of Botany, 104:775-784. pdf

Shahba, M.A. and W.L. Bauerle. 2009. Growth temperature modulates the spatial variability of leaf morphology and chemical elements within crowns of climatically divergent Acer rubrum genotypes. Tree Physiology, 29:869-877. pdf

Klos, R.J., G.G. Wang, W.L. Bauerle, and J.R. Rieck, 2009. Drought impact on forest growth and mortality in the southeast USA: an analysis using Forest Health and Monitoring data. Ecological Applications, 19:699-708. pdf

Bauerle, T.L., D.R. Smart, W.L. Bauerle, C. Stockert, and D.M. Eissenstat, 2008. Root foraging in response to heterogeneous soil moisture in two grapevines that differ in potential growth rate. New Phytologist, 179: 857-866. pdf

Bowden, J.D. and W. L. Bauerle, 2008. Measuring and modeling the variation in species-specific transpiration in temperate deciduous hardwoods. Tree Physiology, 28:1675–1683. pdf

Wang, Y., W.L. Bauerle, and R.F. Reynolds. 2008. Predicting the growth of deciduous tree species in response to water stress: FVS-BGC model parameterization, application, and evaluation. Ecological Modelling, 217:139–147. pdf

Bauerle, W.L., J.D. Bowden, and G.G. Wang. 2007. The influence of temperature on within-canopy acclimation and variation in leaf photosynthesis and respiration: Spatial acclimation to microclimate gradients among thermally divergent Acer rubrum L. genotypes. Journal of Experimental Botany, 58:3285-3298. pdf

Weston, D.J., W.L. Bauerle, G.A. Swire-Clark, B.D. Moore, and W.V. Baird. 2007. Characterization of Rubisco activase from thermally contrasting genotypes of Acer rubrum L. (Aceraceae). American Journal of Botany, 94:926-934. pdf

Weston, D.J. and W.L. Bauerle. 2007. Inhibition and acclimation of C3 photosynthesis to moderate heat: A perspective from thermally contrasting genotypes of Acer rubrum L. (red maple). Tree Physiology, 27:1083-1092. pdf

Thomas, C.N., W.L. Bauerle, T.O. Owino, J.P. Chastain, and S.J. Klaine. 2007. Influence of brick air scrubber by-product on growth and development of corn and hybrid poplar. Bioresource Technology, 98:1085-1094. pdf

Cermak, J., J. Kucera, W.L. Bauerle, N. Phillips, and T.M. Hinckley. 2007. Tree water storage and its diurnal dynamics related to sap flow and changes of stem volume in old-growth Douglas-fir trees. Tree Physiology, 27:181-198. pdf

Bauerle, W.L., G.G. Wang, J.D. Bowden, and C.M. Hong. 2006. An analysis of ecophysiological responses to drought in American chestnut. Annals of Forest Science, 63:833-842. pdf

Baldwin, C.M., H. Liu, L.B. McCarty, W.L. Bauerle, and J.E. Toler. 2006. Response of six bermudagrass cultivars to different irrigation intervals. HortTechnology, 16:466-470. pdf

Wang, G.G., W.L. Bauerle, and B.T. Mudder. 2006. Effects of light acclimation on the photosynthesis, growth, and biomass allocation in American chestnut seedlings. Forest Ecology and Management, 226:173-180. pdf

Baldwin, C.M., H. Liu, L.B. McCarty, W.L. Bauerle, and J.E. Toler. 2006. Effects of Trinexapac-Ethyl on the salinity tolerance of two ultradwarf bermudagrass cultivars. HortScience, 41:808-814. pdf

Thomas, C.N., W.L. Bauerle, J.P. Chastain, T.O. Owino, K.P. Moore, and S.J. Klaine. 2006. Effects of scrubber by-product-stabilized dairy lagoon sludge on growth and physiological response of Sunflower (Helianthus annuus L.). Chemosphere, 64:152-160. pdf

Wang, G.G., S. Chhin, and W.L. Bauerle. 2006. Effect of natural atmospheric CO2 fertilization suggested by open-grown white spruce in a dry environment. Global Change Biology, 12:601-610. pdf

Bauerle, W.L., W.W. Inman, and J.B. Dudley. 2006. Leaf abscisic acid accumulation in response to substrate water content: Linking leaf gas exchange regulation with leaf abscisic acid concentration. Journal of the American Society for Horticulture Science, 131:295-301. pdf

Wang, G.G. and W.L. Bauerle. 2006. Effects of light intensity on the growth and energy balance of Photosystem II electron transport in Quercus alba seedlings. Annals of Forest Science, 63:111-118. pdf

Bauerle, W.L., D.J. Timlin, Ya.A. Pachepsky, and S. Anantharamu. 2006. Adaptation of the biological simulation model MAESTRA for use in a generic user interface. Agronomy Journal, 98:220-228. pdf

Wang, G.G., D.H. Van Lear, and W.L. Bauerle. 2005. Effects of prescribed fires on first-year establishment of white oak (Quercus alba L.) seedlings in the Upper Piedmont of South Carolina, USA. Forest Ecology and Management, 213:328-337. pdf

Baldwin, C.M., H. Liu, L.B. McCarty, W.L. Bauerle, and J.E. Toler. 2005. Aluminum tolerance of ten warm-season turfgrasses. International Turfgrass Society Research Journal, 10:811-817. pdf

Bauerle, W.L. and J.D. Bowden. 2004. A fiber-optic-based system for integrating photosynthetically active radiation in plant canopies. HortScience, 39:1027-1029. pdf

Bauerle, W.L., J.E. Toler, and G.G. Wang. 2004. The stomatal conductance of Acer rubrum L. ecotypes under varying soil and atmospheric water conditions: Predicting stomatal responses with an abscisic acid-based model. Tree Physiology, 24:805-811. pdf

Bauerle, W.L., J.D. Bowden, M.F. McLeod, and J.E. Toler. 2004. Modeling intracrown and intracanopy interactions in red maple: Assessment of light transfer on carbon dioxide and water vapor exchange. Tree Physiology, 24:589-597. pdf

Bauerle, W.L., D.J. Weston, J.D. Bowden, J.B. Dudley, and J.E. Toler. 2004. Leaf absorptance of photosynthetically active radiation in relation to chlorophyll meter estimates among woody plant species. Scientia Horticulturae, 101:169-178. pdf

Bauerle, W.L., T. H. Whitlow, T.L. Setter, and F.M. Vermeylen. 2004. Abscisic acid synthesis in Acer rubrum L. leaves—A vapor pressure deficit mediated response. Journal of the American Society for Horticulture Science, 129:182-187. pdf

Bauerle, W.L., T. H. Whitlow, T.L. Setter, T.L. Bauerle, and F.M. Vermeylen. 2003. Ecophysiology of Acer rubrum L. seedlings from contrasting hydrologic habitats: Growth, gas exchange, tissue water relations, abscisic acid, and carbon isotope discrimination. Tree Physiology, 23:841-850. pdf

Bauerle, W.L., J.B. Dudley, and L.W. Grimes. 2003. Genotypic variability in photosynthesis, water use, and light absorption among red and Freeman maple cultivars in response to drought stress. Journal of the American Society for Horticulture Science, 128:327-332. pdf

Bauerle, W.L., C.J. Post, M.E. McLeod, J.B. Dudley, and J.E. Toler. 2002. Measurement and modeling of the transpiration of a temperate red maple container nursery. Agricultural and Forest Meteorology, 114:45-57. pdf

Bauerle, W.L., T.H. Whitlow, C.R. Pollock, and E.A. Frongillo. 2002. A laser-diode-based system for measuring sap flow by the heat-pulse method. Agricultural and Forest Meteorology, 110:275-284. pdf

Bauerle, W.L., T.M. Hinckley, J. Cermak, J. Kucera, and K. Bible. 1999. The canopy water relations of old growth Douglas-fir trees. Trees ‘Structure and Function’, 13:211-217. pdf

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