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Title: Topsoil depth substantially influences the responses to drought of the foliar metabolomes of Mediterranean forests

Abstract

Soils provide physical support, water, and nutrients to terrestrial plants. Upper soil layers are crucial for forest dynamics, especially under drought conditions, because many biological processes occur there and provide support, water and nutrients to terrestrial plants. We postulated that tree size and overall plant function manifested in the metabolome composition, the total set of metabolites, were dependent on the depth of upper soil layers and on water availability. We sampled leaves for stoichiometric and metabolomic analyses once per season from differently sized Quercus ilex trees under natural and experimental drought conditions as projected for the coming decades. Different sized trees had different metabolomes and plots with shallower soils had smaller trees. Soil moisture of the upper soil did not explain the tree size and smaller trees did not show higher concentrations of biomarker metabolites related to drought stress. However, the impact of drought treatment on metabolomes was higher in smaller trees in shallower soils. Our results suggested that tree size was more dependent on the depth of the upper soil layers, which indirectly affect the metabolomes of the trees, than on the moisture content of the upper soil layers. Metabolomic profiling of Q. ilex supported the premise that watermore » availability in the upper soil layers was not necessarily correlated with tree size. The higher impact of drought on trees growing in shallower soils nevertheless indicates a higher vulnerability of small trees to the future increase in frequency, intensity, and duration of drought projected for the Mediterranean Basin and other areas. Metabolomics has proven to be an excellent tool detecting significant metabolic changes among differently sized individuals of the same species and it improves our understanding of the connection between plant metabolomes and environmental variables such as soil depth and moisture content.« less

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States). Environmental Molecular Sciences Lab. (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1324909
Report Number(s):
PNNL-SA-117183
Journal ID: ISSN 1433-8319; 48729; KP1704020
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Perspectives in Plant Ecology, Evolution and Systematics; Journal Volume: 21; Journal Issue: C
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; Environmental Molecular Sciences Laboratory

Citation Formats

Rivas-Ubach, Albert, Barbeta, Adrià, Sardans, Jordi, Guenther, Alex, Ogaya, Romà, Oravec, Michal, Urban, Otmar, and Peñuelas, Josep. Topsoil depth substantially influences the responses to drought of the foliar metabolomes of Mediterranean forests. United States: N. p., 2016. Web. doi:10.1016/j.ppees.2016.06.001.
Rivas-Ubach, Albert, Barbeta, Adrià, Sardans, Jordi, Guenther, Alex, Ogaya, Romà, Oravec, Michal, Urban, Otmar, & Peñuelas, Josep. Topsoil depth substantially influences the responses to drought of the foliar metabolomes of Mediterranean forests. United States. doi:10.1016/j.ppees.2016.06.001.
Rivas-Ubach, Albert, Barbeta, Adrià, Sardans, Jordi, Guenther, Alex, Ogaya, Romà, Oravec, Michal, Urban, Otmar, and Peñuelas, Josep. 2016. "Topsoil depth substantially influences the responses to drought of the foliar metabolomes of Mediterranean forests". United States. doi:10.1016/j.ppees.2016.06.001.
@article{osti_1324909,
title = {Topsoil depth substantially influences the responses to drought of the foliar metabolomes of Mediterranean forests},
author = {Rivas-Ubach, Albert and Barbeta, Adrià and Sardans, Jordi and Guenther, Alex and Ogaya, Romà and Oravec, Michal and Urban, Otmar and Peñuelas, Josep},
abstractNote = {Soils provide physical support, water, and nutrients to terrestrial plants. Upper soil layers are crucial for forest dynamics, especially under drought conditions, because many biological processes occur there and provide support, water and nutrients to terrestrial plants. We postulated that tree size and overall plant function manifested in the metabolome composition, the total set of metabolites, were dependent on the depth of upper soil layers and on water availability. We sampled leaves for stoichiometric and metabolomic analyses once per season from differently sized Quercus ilex trees under natural and experimental drought conditions as projected for the coming decades. Different sized trees had different metabolomes and plots with shallower soils had smaller trees. Soil moisture of the upper soil did not explain the tree size and smaller trees did not show higher concentrations of biomarker metabolites related to drought stress. However, the impact of drought treatment on metabolomes was higher in smaller trees in shallower soils. Our results suggested that tree size was more dependent on the depth of the upper soil layers, which indirectly affect the metabolomes of the trees, than on the moisture content of the upper soil layers. Metabolomic profiling of Q. ilex supported the premise that water availability in the upper soil layers was not necessarily correlated with tree size. The higher impact of drought on trees growing in shallower soils nevertheless indicates a higher vulnerability of small trees to the future increase in frequency, intensity, and duration of drought projected for the Mediterranean Basin and other areas. Metabolomics has proven to be an excellent tool detecting significant metabolic changes among differently sized individuals of the same species and it improves our understanding of the connection between plant metabolomes and environmental variables such as soil depth and moisture content.},
doi = {10.1016/j.ppees.2016.06.001},
journal = {Perspectives in Plant Ecology, Evolution and Systematics},
number = C,
volume = 21,
place = {United States},
year = 2016,
month = 8
}
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