Table of Contents
International Scholarly Research Notices
Volume 2014, Article ID 427194, 6 pages
http://dx.doi.org/10.1155/2014/427194
Research Article

Complementary N Uptake Strategies between Tree Species in Tropical Rainforest

1INRA, UMR Ecologie des Forêts de Guyane, Campus Agronomique, BP 709, 97387 Kourou Cedex, French Guiana
2UMR Botanique et Bioinformatique de l’Architecture des Plantes (AMAP), TA A51/ PS2, 34398 Montpellier Cedex 5, France
3UR Dynamique des Forets Naturelles, TA C-37/D, Campus International de Baillarguet, 34398 Montpellier Cedex 5, France
4Solicaz, c/o Guyane Technopole, 16 bis rue du 14 Juillet, 97 300 Cayenne, French Guiana

Received 12 June 2014; Accepted 18 August 2014; Published 29 October 2014

Academic Editor: Diederik Van Tuinen

Copyright © 2014 J. C. Roggy et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Within tree communities, the differential use of soil N mineral resources, a key factor in ecosystem functioning, may reflect functional complementarity, a major mechanism that could explain species coexistence in tropical rainforests. Eperua falcata and Dicorynia guianensis, two abundant species cooccurring in rainforests of French Guiana, were chosen as representative of two functional groups with complementary N uptake strategies (contrasting leaf δ15N signatures related to the δ15N of their soil N source, or ). The objectives were to investigate if these strategies occurred under contrasted soil N resources in sites with distinct geological substrates representative of the coastal rainforests. Results showed that species displayed contrasting leaf δ15N signatures on both substrates, confirming their complementary N uptake strategy. Consequently, their leaf 15N can be used to trace the presence of inorganic N-forms in soils ( and ) and thus to indicate the capacity of soils to provide each of these two N sources to the plant community.