@Article{Bonal_etal2011,
author="Bonal, D.
and Ponton, S.
and Le Thiec, D.
and Richard, B.
and Ningre, N.
and Herault, B.
and Ogee, J.
and Gonzalez, S.
and Pignal, M.
and Sabatier, D.
and Guehl, J.M.",
title="Leaf functional response to increasing atmospheric CO(2) concentrations over the last century in two northern Amazonian tree species: a historical delta(13)C and delta(18)O approach using herbarium samples",
journal="Plant Cell and Environment",
year="2011",
publisher="Wiley-Blackwell",
volume="34",
number="8",
pages="1332--1344",
optkeywords="carbon isotope composition",
optkeywords="environmental change",
optkeywords="herbarium",
optkeywords="oxygen isotope composition",
optkeywords="photosynthesis",
optkeywords="stomata",
optkeywords="tropical rainforests",
abstract="We assessed the extent of recent environmental changes on leaf morphological (stomatal density, stomatal surface, leaf mass per unit area) and physiological traits (carbon isotope composition, delta(13)C(leaf), and discrimination, Delta(13)C(leaf), oxygen isotope composition, delta(18)O(leaf)) of two tropical rainforest species (Dicorynia guianensis; Humiria balsamifera) that are abundant in the Guiana shield (Northern Amazonia). Leaf samples were collected in different international herbariums to cover a 200 year time-period (1790-2004) and the whole Guiana shield. Using models describing carbon and oxygen isotope fractionations during photosynthesis, different scenarios of change in intercellular CO(2) concentrations inside the leaf (C(i)), stomatal conductance (g), and photosynthesis (A) were tested in order to understand leaf physiological response to increasing air CO(2) concentrations (C(a)). Our results confirmed that both species displayed physiological response to changing C(a). For both species, we observed a decrease of about 1.7\% in delta(13)C(leaf) since 1950, without significant change in Delta(13)C(leaf) and leaf morphological traits. Furthermore, there was no clear change in delta(18)O(leaf) for Humiria over this period. Our simulation approach revealed that an increase in A, rather than a decrease in g, explained the observed trends for these tropical rainforest species, allowing them to maintain a constant ratio of C(i)/C(a).",
optnote="WOS:000292698900010",
optnote="exported from refbase (http://php.ecofog.gf/refbase/show.php?record=330), last updated on Thu, 28 Jul 2011 18:16:04 -0300",
issn="0140-7791"
}