Interannual variability of ecosystem iso/anisohydry is regulated by environmental dryness

Genghong Wu; Kaiyu Guan; Yan Li; Kimberly A Novick; Xue Feng; Nate G McDowell; Alexandra G Konings; Sally E Thompson; John S Kimball; Martin G De Kauwe; Elizabeth A Ainsworth; Chongya Jiang

doi:10.1111/nph.17040

Interannual variability of ecosystem iso/anisohydry is regulated by environmental dryness

New Phytol. 2021 Mar;229(5):2562-2575. doi: 10.1111/nph.17040. Epub 2020 Dec 3.

Authors

Genghong Wu¹, Kaiyu Guan^{1

2}, Yan Li³, Kimberly A Novick⁴, Xue Feng⁵, Nate G McDowell⁶, Alexandra G Konings⁷, Sally E Thompson^{8

9}, John S Kimball¹⁰, Martin G De Kauwe^{11

12

13}, Elizabeth A Ainsworth^{14

15}, Chongya Jiang¹

Affiliations

¹ College of Agricultural, Consumer and Environmental Sciences, University of Illinois at Urbana Champaign, Urbana, IL, 61801, USA.
² National Center for Supercomputing Applications, University of Illinois at Urbana Champaign, Champaign, IL, 61820, USA.
³ State Key Laboratory of Earth Surface Processes and Resources Ecology, Faculty of Geographical Science, Beijing Normal University, Beijing, 100875, China.
⁴ O'Neill School of Public and Environmental Affairs, Indiana University Bloomington, Bloomington, IN, 47405, USA.
⁵ Department of Civil, Environmental, and Geo-Engineering, University of Minnesota, Minneapolis, MN, 55455, USA.
⁶ Earth Systems Science Division, Pacific Northwest National Laboratory, Richland, WA, 99352, USA.
⁷ Department of Earth System Science, Stanford University, Stanford, CA, 94305, USA.
⁸ Department of Civil and Environmental Engineering, University of California Berkeley, Berkeley, CA, 94720, USA.
⁹ Department of Civil, Environmental and Mining Engineering, University of Western Australia, Crawley, WA, 6009, Australia.
¹⁰ Numerical Terra dynamic Simulation Group, College of Forestry & Conservation, University of Montana, Missoula, MT, 59812, USA.
¹¹ ARC Australia Centre of Excellence for Climate Extremes, Sydney, NSW, 2052, Australia.
¹² Climate Change Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia.
¹³ Evolution and Ecology Research Centre, University of New South Wales, Sydney, NSW, 2052, Australia.
¹⁴ Department of Plant Biology, University of Illinois at Urbana Champaign, Urbana, IL, 61801, USA.
¹⁵ USDA ARS Global Change and Photosynthesis Research Unit, Urbana, IL, 61801, USA.

PMID: 33118166
DOI: 10.1111/nph.17040

Abstract

●Plants are characterized by the iso/anisohydry continuum depending on how they regulate leaf water potential (Ψ_L ). However, how iso/anisohydry changes over time in response to year-to-year variations in environmental dryness and how such responses vary across different regions remains poorly characterized. ●We investigated how dryness, represented by aridity index, affects the interannual variability of ecosystem iso/anisohydry at the regional scale, estimated using satellite microwave vegetation optical depth (VOD) observations. This ecosystem-level analysis was further complemented with published field observations of species-level Ψ_L . ●We found different behaviors in the directionality and sensitivity of isohydricity (σ) with respect to the interannual variation of dryness in different ecosystems. These behaviors can largely be differentiated by the average dryness of the ecosystem itself: in mesic ecosystems, σ decreases in drier years with a higher sensitivity to dryness; in xeric ecosystems, σ increases in drier years with a lower sensitivity to dryness. These results were supported by the species-level synthesis. ●Our study suggests that how plants adjust their water use across years - as revealed by their interannual variability in isohydricity - depends on the dryness of plants' living environment. This finding advances our understanding of plant responses to drought at regional scales.

Keywords: anisohydry; dryness; interannual variability; isohydry; leaf water potential; vegetation optical depth (VOD).

Publication types

Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Droughts*
Ecosystem*
Plant Leaves
Plants
Water

Substances

Water