Premium
Quantifying vulnerability to embolism in tropical trees and lianas using five methods: can discrepancies be explained by xylem structural traits?
Author(s) -
Chen YaJun,
Maenpuen Phisamai,
Zhang YongJiang,
Barai Kallol,
Katabuchi Masatoshi,
Gao Hui,
Kaewkamol Sasiwimol,
Tao LianBin,
Zhang JiaoLin
Publication year - 2021
Publication title -
new phytologist
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.742
H-Index - 244
eISSN - 1469-8137
pISSN - 0028-646X
DOI - 10.1111/nph.16927
Subject(s) - xylem , liana , drought stress , environmental science , shrinkage , soil science , materials science , biological system , biomedical engineering , horticulture , biology , botany , medicine , composite material
Summary Vulnerability curves (VCs) describe the loss of hydraulic conductance against increasing xylem tension, providing valuable insights about the response of plant water transport to water stress. Techniques to construct VCs have been developed and modified continuously, but controversies continue. We compared VCs constructed using the bench‐top dehydration (BD), air‐injection‐flow (AI), pneumatic‐air‐discharge (PAD), optical (OP) and X‐ray‐computed microtomography (MicroCT) methods for tropical trees and lianas with contrasting vessel lengths. The PAD method generated highly vulnerable VCs, the AI method intermediate VCs, whereas the BD, OP and MicroCT methods produced comparable and more resistant VCs. Vessel‐length and diameter accounted for the overestimation ratio of vulnerability estimated using the AI but not the PAD method. Compared with directly measured midday embolism levels, the PAD and AI methods substantially overestimated embolism, whereas the BD, MicroCT and OP methods provided more reasonable estimations. Cut‐open vessels, uncertainties in maximum air volume estimations, sample‐length effects, tissue cracks and shrinkage together may impede the reliability of the PAD method. In conclusion, we validate the BD, OP and MicroCT methods for tropical plants, whereas the PAD and AI need further mechanistic testing. Therefore, applications of VCs in estimating plant responses to drought need to be cautious.