Transport in a coordinated soil-root-xylem-phloem leaf system
Date
2018-09
Journal Title
Journal ISSN
Volume Title
Repository Usage Stats
views
downloads
Citation Stats
Abstract
© 2018 Elsevier Ltd Links between the carbon and water economies of plants are coupled by combining the biochemical demand for atmospheric CO2with gas transfer through stomates, liquid water transport in the soil-xylem hydraulic system and sucrose export in the phloem. We formulated a model to predict stomatal conductance (gs), consistent with the maximum energy circulation concept of Lotka and Odum, by maximizing the sucrose flux out of photosynthesizing leaves. The proposed modeling approach recovers all prior results derived from stomatal optimization theories and profit-maximization arguments for the xylem hydraulic system aimed at predicting gs. The novel features of this approach are its ability to 1) predict the price of losing water in carbon units using xylem and phloem properties (i.e., the marginal water use efficiency) and 2) explain why water molecules become more expensive to exchange for CO2molecules when soil moisture becomes limiting or when plants acclimate to new elevated atmospheric CO2concentration. On short time-scales (sub-daily), predicted gsunder many environmental stimuli were consistent with measurements reported in the literature, including a general sensitivity of gsto vapor pressure deficit and leaf water potential. During progressive droughts, differences in the coordination among the leaf, xylem, and phloem functioning determine the isohydric-to-anisohydric behavior among plants.
Type
Department
Description
Provenance
Subjects
Citation
Permalink
Published Version (Please cite this version)
Publication Info
Huang, CW, JC Domec, S Palmroth, WT Pockman, ME Litvak and GG Katul (2018). Transport in a coordinated soil-root-xylem-phloem leaf system. Advances in Water Resources, 119. pp. 1–16. 10.1016/j.advwatres.2018.06.002 Retrieved from https://hdl.handle.net/10161/17324.
This is constructed from limited available data and may be imprecise. To cite this article, please review & use the official citation provided by the journal.
Collections
Scholars@Duke

Jean Christophe Domec
Bordeaux Sciences Agro in FRANCE (primary appointment)
Discovery of knowledge in Plant water relations, ecosystem ecology and ecohydrology, with special focus on: - Long-distance water transport under future climate; - Drought tolerance and avoidance; - Patterns of changes in structural and functional traits within individual plants. My goal as a researcher is to improve the fundamental science understanding of how plants and terrestrial ecosystems respond to climate changes, and to provide tree breeders with policy-relevant information. I have carried out research on interactions between soil water and plant water use in contrasting ecosystems, in cooperation with scientists at Bordeaux Sciences Agro in FRANCE (primary appointment), Duke University, Oregon State University, and the USDA Forest Service, Southern Global Change Program, recently renamed EFETAC (Eastern Forest Environmental Threat Assessment Center).

Sari Palmroth
Dr. Palmroth's research focuses on the effects of resource availability and climatic variability on carbon uptake and allocation of individual shoots, trees and forest ecosystems. She studies ecophysiological processes in trees from leaf to stand scales, with special emphasis on conifers. In particular, Dr. Palmroth is interested in the radiative transfer in forest canopies, how the radiation regime is affected by conifer shoot structure, and what the feedbacks are between availability of solar energy and allocation on carbon and nitrogen within canopies. She is also interested in how the carbon fixed in photosynthesis is allocated between above and belowground pools and what are the possible interaction effects on the allocation of the availabilities of nutrients and water and the level of atmospheric [CO2].

Gabriel G. Katul
Gabriel G. Katul received his B.E. degree in 1988 at the American University of Beirut (Beirut, Lebanon), his M.S. degree in 1990 at Oregon State University (Corvallis, OR) and his Ph.D degree in 1993 at the University of California in Davis (Davis, CA). He currently holds a distinguished Professorship in Hydrology and Micrometeorology at the Department of Civil and Environmental Engineering at Duke University (Durham, NC). He was a visiting fellow at University of Virginia (USA) in 1997, the Commonwealth Science and Industrial Research Organization (Australia) in 2002, the University of Helsinki (Finland) in 2009, the FulBright-Italy Distinguished Fellow at Politecnico di Torino (Italy) in 2010, the École polytechnique fédérale de Lausanne (Switzerland) in 2013, Nagoya University (Japan) in 2014, University of Helsinki (Finland) in 2017, the Karlsruher Institute for Technology (Germany) in 2017, Princeton University (USA) in 2020, and CzechGlobe (Brno - Czech Republic) in 2023. He received several honorary awards, including the inspirational teaching award by the students of the School of the Environment at Duke University (in 1994 and 1996), an honorary certificate by La Seccion de Agrofisica de la Sociedad Cubana de Fisica in Habana (in 1998), the Macelwane medal and became thereafter a fellow of the American Geophysical Union (in 2002), the editor’s citation for excellence in refereeing from the American Geophysical Union (in 2008), the Hydrologic Science Award from the American Geophysical Union (in 2012), the John Dalton medal from the European Geosciences Union (in 2018), the Outstanding Achievements in Biometeorology Award from the American Meteorological Society (in 2021) and later became an elected fellow of the American Meteorological Society (in 2024), and the recipient of the American Meteorological Society hydrologic science medal (in 2025). Katul was elected to the National Academy of Engineering (in 2023) for his contributions in eco-hydrology and environmental fluid mechanics. He served as the Secretary General for the Hydrologic Science Section at the American Geophysical Union (2006-2008). His research focuses on micro-meteorology and near-surface hydrology with emphasis on heat, momentum, carbon dioxide, water vapor, ozone, particulate matter (including aerosols, pollen, and seeds) and water transport in the soil-plant-atmosphere system as well as their implications to a plethora of hydrological, ecological, atmospheric and climate change related problems.
Unless otherwise indicated, scholarly articles published by Duke faculty members are made available here with a CC-BY-NC (Creative Commons Attribution Non-Commercial) license, as enabled by the Duke Open Access Policy. If you wish to use the materials in ways not already permitted under CC-BY-NC, please consult the copyright owner. Other materials are made available here through the author’s grant of a non-exclusive license to make their work openly accessible.