Dataset Information

Non-structural carbohydrate dynamics associated with drought-induced die-off in woody species of a shrubland community.

ABSTRACT:

Background and aims

The relationship between plant carbon economy and drought responses of co-occurring woody species can be assessed by comparing carbohydrate (C) dynamics following drought and rain periods, relating these dynamics to species' functional traits. We studied nine woody species coexisting in a continental Mediterranean shrubland that experienced severe drought effects followed by rain.

Methods

We measured total non-structural carbohydrates (NSC) and soluble sugars (SS) in roots and stems during drought and after an autumn rain pulse in plants exhibiting leaf loss and in undefoliated ones. We explored whether their dynamics were related to foliage recovery and functional traits (height [H], specific leaf area [SLA], wood density [WD]).

Key results

During drought, NSC concentrations were overall lower in stems and roots of plants experiencing leaf loss, while SS decreases were smaller. Roots had higher NSC concentrations than stems. After the rain, NSC concentrations continued to decrease, while SS increased. Green foliage recovered after rain, particularly in plants previously experiencing higher leaf loss, independently of NSC concentrations during drought. Species with lower WD tended to have more SS during drought and lower SS increases after rain. In low-WD species, plants with severe leaf loss had lower NSC relative to undefoliated ones. No significant relationship was found between H or SLA and C content or dynamics.

Conclusions

Our community-level study reveals that, while responses were species-specific, C stocks overall diminished in plants affected by prolonged drought and did not increase after a pulse of seasonal rain. Dynamics were faster for SS than NSC. We found limited depletion of SS, consistent with their role in basal metabolic, transport and signalling functions. In a scenario of increased drought under climate change, NSC stocks in woody plants are expected to decrease differentially in coexisting species, with potential implications for their adaptive abilities and community dynamics.

SUBMITTER: Lloret F

PROVIDER: S-EPMC6007552 | biostudies-literature | 2018 Jun

REPOSITORIES: biostudies-literature

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Publications

Non-structural carbohydrate dynamics associated with drought-induced die-off in woody species of a shrubland community.

Lloret Francisco F Sapes Gerard G Rosas Teresa T Galiano Lucía L Saura-Mas Sandra S Sala Anna A Martínez-Vilalta Jordi J

Annals of botany 20180601 7

<h4>Background and aims</h4>The relationship between plant carbon economy and drought responses of co-occurring woody species can be assessed by comparing carbohydrate (C) dynamics following drought and rain periods, relating these dynamics to species' functional traits. We studied nine woody species coexisting in a continental Mediterranean shrubland that experienced severe drought effects followed by rain.<h4>Methods</h4>We measured total non-structural carbohydrates (NSC) and soluble sugars ( ...[more]

PMID: 29893878

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Dataset Information

Non-structural carbohydrate dynamics associated with drought-induced die-off in woody species of a shrubland community.

Background and aims

Methods

Key results

Conclusions

Publications

Non-structural carbohydrate dynamics associated with drought-induced die-off in woody species of a shrubland community.

Similar Datasets

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