Anne-Marie Domenach

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Cross-species analyses of plant functional traits have shed light on factors contributing to differences in performance and distribution, but to date most studies have focused on either leaves or stems. We extend these tissue-specific analyses of functional strategy towards a whole-plant approach by integrating data on functional traits for 13 448 leaves(More)
Annual N2-fixation in virgin forest ecosystems has been measured using a15N natural abundance (δ15N) procedure. This method was compared to a15N labelled fertilizer isotopic dilution method. For young alders (5–6 years old), δ15N of leaves gave results in good agreement with the isotopic dilution of fertilizer method. Since δ15N variability was expected(More)
Symbioses between the root nodule-forming, nitrogen-fixing actinomycete Frankia and its angiospermous host plants are important in the nitrogen economies of numerous terrestrial ecosystems. Molecular characterization of Frankia strains using polymerase chain reaction/restriction fragment length polymorphism (PCR/RFLP) analyses of the 16S rRNA-ITS gene and(More)
Functional aspects of biodiversity were investigated in a lowland tropical rainforest in French Guyana (5°2′N, annual precipitation 2200 mm). We assessed leaf δ15N as a presumptive indicator of symbiotic N2 fixation, and leaf and wood cellulose δ13C as an indicator of leaf intrinsic water-use efficiency (CO2 assimilation rate/leaf conductance for water(More)
Three15N isotopic dilution methods (15N natural abundance, labelled mineral fertilizer, and organic matter) were used to determine the proportion of N derived from different available sources in seedlines ofAlnus glutinosa andPopulus nigra planted together or in monoculture under natural climatic conditions. The proportion of N derived from N2 fixation in(More)
The suitability of the natural 15N abundance and of total N concentration of leaves as indicators of the type of plant N nutrition in a rain forest of French Guiana were tested. Leaf samples from primary legume species, non-legumes (pioneer species) and from the non-N2-fixing species Dicorynia guianensis were analyzed. Both δ15N and total leaf N varied(More)
The nifD-K intergenic spacer (IGS) of ArI3 and ACoN24d were found to have a length 265 and 199 nucleotides, respectively. They are markedly less conserved than the two neighbouring genes and have, in some instances, a repeated structure reminiscent of an insertion event. The repeated sequence and the IGSs have no detectable homology with sequences in DNA(More)
Field experiments about denitrification and nitrification processes have been performed in a wet savanna of West Africa (Lamto, Côte d'Ivoire). Two scales have been chosen: (i) a topographic gradient including the main forest and savanna environments; (ii) a soil profile taking into account roots and fauna effects. Denitrifying potential activity was only(More)
Two methods of N transfer between plants—by litter decomposition and root-to-root exchange—were examined in mixed plantations of N-fixing and non-fixing trees. Nitrogen transfers from decaying litters were measured by placing 15N-labelled litters from four actinorhizal tree species around shoots of containerized Prunus avium. Nitrogen transfers by(More)
Phenylacetic hopanetetrol is a Frankia specific lipid present in vesicles. Phenylacetic acid (PAA) is known as an auxinomimetic, exhibiting the same effect on plant growth as indole acetic acid (IAA). We hypothesize that PAA, only bound by an ester link to the hopanetetrol basic unit, would be easily released and could thus play a role in nodule formation.(More)