Hydraulic failure and tree size linked with canopy die-back in eucalypt forest during extreme drought

Hydraulic failure and tree size linked with canopy die-back in eucalypt forest during extreme drought

© 2021 The Authors New Phytologist © 2021 New Phytologist Foundation.

Bibliographische Detailangaben
Veröffentlicht in:The New phytologist. - 1979. - 230(2021), 4 vom: 25. Mai, Seite 1354-1365
1. Verfasser: Nolan, Rachael H (VerfasserIn)
Weitere Verfasser: Gauthey, Alice, Losso, Adriano, Medlyn, Belinda E, Smith, Rhiannon, Chhajed, Shubham S, Fuller, Kathryn, Song, Magnolia, Li, Xine, Beaumont, Linda J, Boer, Matthias M, Wright, Ian J, Choat, Brendan
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:The New phytologist
Schlagworte:Journal Article Research Support, Non-U.S. Gov't Eucalyptus cavitation drought hydraulic failure mortality tree size water potential xylem embolism mehr... Water 059QF0KO0R
Beschreibung
Zusammenfassung:© 2021 The Authors New Phytologist © 2021 New Phytologist Foundation.
Eastern Australia was subject to its hottest and driest year on record in 2019. This extreme drought resulted in massive canopy die-back in eucalypt forests. The role of hydraulic failure and tree size on canopy die-back in three eucalypt tree species during this drought was examined. We measured pre-dawn and midday leaf water potential (Ψleaf ), per cent loss of stem hydraulic conductivity and quantified hydraulic vulnerability to drought-induced xylem embolism. Tree size and tree health was also surveyed. Trees with most, or all, of their foliage dead exhibited high rates of native embolism (78-100%). This is in contrast to trees with partial canopy die-back (30-70% canopy die-back: 72-78% native embolism), or relatively healthy trees (little evidence of canopy die-back: 25-31% native embolism). Midday Ψleaf was significantly more negative in trees exhibiting partial canopy die-back (-2.7 to -6.3 MPa), compared with relatively healthy trees (-2.1 to -4.5 MPa). In two of the species the majority of individuals showing complete canopy die-back were in the small size classes. Our results indicate that hydraulic failure is strongly associated with canopy die-back during drought in eucalypt forests. Our study provides valuable field data to help constrain models predicting mortality risk
Beschreibung:Date Completed 14.05.2021
Date Revised 23.08.2023
published: Print-Electronic
Citation Status MEDLINE
ISSN:1469-8137
DOI:10.1111/nph.17298