Life after disturbance (II): the intermediate disturbance hypothesis explains genetic variation in forest gaps dominated by Virola michelii Heckel (Myristicaceae) - AgroParisTech Access content directly
Journal Articles Annals of Forest Science Year : 2015

Life after disturbance (II): the intermediate disturbance hypothesis explains genetic variation in forest gaps dominated by Virola michelii Heckel (Myristicaceae)

Abstract

Key message: Genetic diversity appears to be unaffected by disturbance in a stand of the light-demanding Neotropical treeV. michelii. Although spatial genetic structure is modified in post-disturbance cohorts, mixing of seeds from different mother trees in canopy gaps appears to efficiently maintain genetic admixture. Context: The interplay between genetic and demographic processes has major consequences on population viability. Population size affects demographic trends, while genetic diversity insures viability by reducing risks of inbreeding depression and by maintaining adaptive potential. Yet, the consequences of increases in census size (as opposed to effective size) on genetic diversity of forest populations are poorly known. Aims: We have studied the structure of genetic diversity in populations of saplings of the light-responsive tree, Virola michelii (Myristicaceae, the nutmeg family), in two plots having undergone different levels of canopy-gap opening disturbance. This allowed us to test the “intermediate disturbance” hypothesis, which generally applies to species diversity, at the intra-specific scale. Methods: Levels and distribution of genetic diversity were compared between plots and between life stages. Sapling parentage was analysed to infer each adult tree’s contribution to regeneration. Results: Genetic diversity was higher, and spatial genetic structure was stronger in the post-disturbance than in the control seedling population. Parentage analysis suggested that a limited number of parents contributed to most of the regeneration, but that efficient mixing of their progeny may have enhanced the diversity of saplings occupying canopy gaps. Conclusion: A mixture of demo-genetic processes may contribute to maintain genetic diversity in spite of, or possibly due to, ecosystem disturbance in V. michelii.
Fichier principal
Vignette du fichier
art_10.1007_s13595-015-0508-3-1_{869D58F4-272C-491F-A903-DAD6CDBDC042}.pdf (613.27 Ko) Télécharger le fichier
Origin : Explicit agreement for this submission
Loading...

Dates and versions

hal-01502942 , version 1 (26-09-2017)

Licence

Copyright

Identifiers

Cite

Ivan Scotti, William Montaigne, Klára Cseke, Stephane Traissac. Life after disturbance (II): the intermediate disturbance hypothesis explains genetic variation in forest gaps dominated by Virola michelii Heckel (Myristicaceae). Annals of Forest Science, 2015, 72 (8), pp.1035 - 1042. ⟨10.1007/s13595-015-0508-3⟩. ⟨hal-01502942⟩
424 View
196 Download

Altmetric

Share

Gmail Facebook Twitter LinkedIn More