Fine‐scale species distribution changes in a mixed oak stand over two successive generations

• DOI: 10.1111/nph.14561
• Publication Date: 2017-04-26T13:07:48Z
• Authors: Laura Truffaut; Emilie Chancerel; Alexis Ducousso; Jean Luc Dupouey; Vincent Badeau; François Ehrenmann; Antoine Kremer
• Keywords: 0106 biological sciences; 570; demography; polymorphisme des nucléotides simples; [SDV]Life Sciences [q-bio]; Population Dynamics; Environment; Polymorphism, Single Nucleotide; 01 natural sciences; Quercus; Species Specificity; approche diachronique; Inbreeding; hybridization; pedunculate oak; 580; Reproduction; sessile oak; 15. Life on land; DNA Fingerprinting; Single nucleotide polymorphism; recruitment; quercus petraea; admixture; regeneration phase; Hybridization, Genetic; changement environnemental; hybridation; quercus robur

Summary

Large‐scale tree distribution changes have received considerable attention but underlying demo‐genetic mechanisms are less well documented. We used a diachronic approach to track species shifts in a mixed oak stand (Quercus petraea–Quercus robur) at a fine spatiotemporal scale. Species assignment was made using single nucleotide polymorphism (SNP) fingerprints employing clustering and parentage analysis. Mating patterns and reproductive success were assessed by parentage analysis. Plot‐based inventories of soil parameters and sapling densities provided ecological and demographic information, respectively. Sapling density and reproductive success was higher in Q. petraea than in Q. robur, and were correlated with a spatial expansion of Q. petraea (50% to 67% of the area). Admixed trees resulting from hybridization and backcrossing between the two species were more frequent under the Q. robur canopy. We suspect that species’ differential responses to ongoing environmental changes and interspecific competition are the predominant factors accounting for the recruitment success of Q. petraea, while human interference, differential reproduction and hybridization (and backcrossings) are probably of more limited importance. We anticipate in mixed Q. petraea–Q. robur stands, under current ongoing environmental change, that these processes will be enhanced, at least in the western part of the distribution of the two species.