Journal Article

Root structure-function relationships in 74 species: evidence of a root economics spectrum related to carbon economy

Guangxi University [Nanning] (GXU), Picon-Cochard, Catherine, Birouste, Marine, Unité de recherche sur l'Ecosystème Prairial (UREP) ; Institut National de la Recherche Agronomique (INRA), Vrignon-Brenas, Sylvain, Ghestem, Murielle, Centre d’Ecologie Fonctionnelle et Evolutive (CEFE) ; Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE) ; Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [Occitanie])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), State Key Lab Conservat & Utilizat Subtrop Agrobi ; Guangxi University [Nanning] (GXU), Cao, Kun-Fang, Stokes, Alexia, Osman, Normaniza, Botanique et Modélisation de l'Architecture des

2016

Overview

Although fine roots are important components of the global carbon cycle, there is limited understanding of root structure-function relationships among species. We determined whether root respiration rate and decomposability, two key processes driving carbon cycling but always studied separately, varied with root morphological and chemical traits, in a coordinated way that would demonstrate the existence of a root economics spectrum (RES). Twelve traits were measured on fine roots (diameter 2mm) of 74 species (31 graminoids and 43 herbaceous and dwarf shrub eudicots) collected in three biomes. The findings of this study support the existence of a RES representing an axis of trait variation in which root respiration was positively correlated to nitrogen concentration and specific root length and negatively correlated to the root dry matter content, lignin:nitrogen ratio and the remaining mass after decomposition. This pattern of traits was highly consistent within graminoids but less consistent within eudicots, as a result of an uncoupling between decomposability and morphology, and of heterogeneity of individual roots of eudicots within the fine-root pool. The positive relationship found between root respiration and decomposability is essential for a better understanding of vegetation-soil feedbacks and for improving terrestrial biosphere models predicting the consequences of plant community changes for carbon cycling.

• Publisher: Wiley,CCSD,New Phytologist Trust,Wiley Subscription Services, Inc
• Subject: Biosphere / carbon / Carbon - metabolism / Carbon cycle / Cell Respiration / correlation / Dry matter / dry matter content / Economics / economics spectrum / ecosystems / Environmental Sciences / eudicots / fine roots / fine‐root traits / Global Changes / graminoids / Heterogeneity / lignin / Linear Models / Nitrogen / nitrogen content / Plant communities / plant diversity / Plant Roots - anatomy & histology / Plant Roots - physiology / prediction / Principal Component Analysis / Respiration / respiratory rate / root decomposability / root respiration / Roots / shrubs / Species Specificity / structure-activity relationships
• ISBN: 0003742867000