Within-Population Genetic Structure in Beech (Fagus sylvatica L.) Stands Characterized by Different Disturbance Histories: Does Forest Management Simplify Population Substructure?

Abstract

The fine-scale assessment of both spatially and non-spatially distributed genetic variation is crucial to preserve forest genetic resources through appropriate forest management. Cryptic within-population genetic structure may be more common than previously thought in forest tree populations, which has strong implications for the potential of forests to adapt to environmental change. The present study was aimed at comparing within-population genetic structure in European beech (Fagus sylvatica L.) plots experiencing different disturbance levels. Five plot pairs made up by disturbed and undisturbed plots having the same biogeographic history were sampled throughout Europe. Overall, 1298 individuals were analyzed using four highly polymorphic nuclear microsatellite markers (SSRs). Bayesian clustering within plots identified 3 to 11 genetic clusters (within-plot θ ST ranged from 0.025 to 0.124). The proportion of within-population genetic variation due to genetic substructuring (F CluPlot = 0.067) was higher than the differentiation among the 10 plots (F PlotTot = 0.045). Focusing on the comparison between managed and unmanaged plots, disturbance mostly explains differences in the complexity of within-population genetic structure, determining a reduction of the number of genetic clusters present in a standardized area. Our results show that: i) genetic substructuring needs to be investigated when studying the within-population genetic structure in forest tree populations, and ii) indices describing subtle characteristics of the within-population genetic structure are good candidates for providing early signals of the consequences of forest management, and of disturbance events in general.

Genetic Insights into Ecological Succession from Oak- (Quercus robur L.) to Beech- (Fagus sylvatica L.) Dominated Forest Stands

“…Forest management may affect genetic diversity (Rajendra et al, 2014) and several studies were focused on the effect of forest management on genetic diversity (Buiteveld et al, 2007;Piotti et al, 2013;Ratnam et al, 2014;Westergren et al, 2015). However, in order to monitor the impacts of forest management and climate changes on genetic diversity of forest trees, intact populations not affected by human activities are needed to serve as a reference autochthonous populations.…”

“…Other authors (Rajendra et al, 2014;Westergren et al, 2015;Kempf and Konnert, 2016) observed relatively low levels of inbreeding. Apparently, when F is is estimated along with accounting for the presence of null alleles, the levels of inbreeding in beech are usually found to be insignificant (Piotti et al, 2013;Pluess and Maattanen, 2013).…”

Genetic Diversity of the Black Mangrove Avicennia germinans (L.) Stearn in Northwestern Mexico

“…Changes in coastal lagoons in Sinaloa, Mexico have been associated mostly with aquaculture, agriculture, livestock and urban development [6]. Human-driven perturbations affect population demography that in turn could potentially lead to reductions in species genetic diversity and changes in patterns of genetic structure [7][8][9]. These disturbances could represent a real threat for the long term ability of species to respond if adaptive genetic traits are lacking [10].…”

An assessment of genetic diversity following natural regeneration of Sorbus torminalis in the Forest District of Jamy (northern Poland)

“…This finding is similar to the results obtained in the studies of spatial genetic structure generated by random events (eg. : Epperson et al 2001;Vekemans and Hardy 2004;Piotti et al 2013). We did not find clear differences between the DBH (age) groups: F st was close to zero and they had very similar observed heterozygosities (Tab.…”