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Title: Hydraulic variability of tropical forests is largely independent of water availability
Abstract Tropical rainforest woody plants have been thought to have uniformly low resistance to hydraulic failure and to function near the edge of their hydraulic safety margin (HSM), making these ecosystems vulnerable to drought; however, this may not be the case. Using data collected at 30 tropical forest sites for three key traits associated with drought tolerance, we show that site‐level hydraulic diversity of leaf turgor loss point, resistance to embolism (P50), and HSMs is high across tropical forests and largely independent of water availability. Species with high HSMs (>1 MPa) and low P50values (< −2 MPa) are common across the wet and dry tropics. This high site‐level hydraulic diversity, largely decoupled from water stress, could influence which species are favoured and become dominant under a drying climate. High hydraulic diversity could also make these ecosystems more resilient to variable rainfall regimes.  more » « less
Award ID(s):
1831952
PAR ID:
10484392
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
Ecology Letters
Date Published:
Journal Name:
Ecology Letters
Volume:
26
Issue:
11
ISSN:
1461-023X
Page Range / eLocation ID:
1829 to 1839
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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