Open AccessPast climatic refugia and landscape resistance explain spatial genetic structure in Oriental beech in the South Caucasus
Author(s) -
Sękiewicz Katarzyna,
Danelia Irina,
Farzaliyev Vahid,
Gholizadeh Hamid,
Iszkuło Grzegorz,
Naqinezhad Alireza,
Ramezani Elias,
Thomas Peter A.,
Tomaszewski Dominik,
Walas Łukasz,
Dering Monika
Publication year - 2022
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.9320
Subject(s) - genetic structure , beech , genetic diversity , range (aeronautics) , ecology , context (archaeology) , resistance (ecology) , climate change , environmental change , species distribution , habitat , geography , adaptation (eye) , biology , population , materials science , demography , archaeology , neuroscience , sociology , composite material
Predicting species‐level effects of climatic changes requires unraveling the factors affecting the spatial genetic composition. However, disentangling the relative contribution of historical and contemporary drivers is challenging. By applying landscape genetics and species distribution modeling, we investigated processes that shaped the neutral genetic structure of Oriental beech ( Fagus orientalis ), aiming to assess the potential risks involved due to possible future distribution changes in the species. Using nuclear microsatellites, we analyze 32 natural populations from the Georgia and Azerbaijan (South Caucasus). We found that the species colonization history is the most important driver of the genetic pattern. The detected west–east gradient of genetic differentiation corresponds strictly to the Colchis and Hyrcanian glacial refugia. A significant signal of associations to environmental variables suggests that the distinct genetic composition of the Azerbaijan and Hyrcanian stands might also be structured by the local climate. Oriental beech retains an overall high diversity; however, in the context of projected habitat loss, its genetic resources might be greatly impoverished. The most affected are the Azerbaijan and Hyrcanian populations, for which the detected genetic impoverishment may enhance their vulnerability to environmental change. Given the adaptive potential of range‐edge populations, the loss of these populations may ultimately affect the specie's adaptation, and thus the stability and resilience of forest ecosystems in the Caucasus ecoregion. Our study is the first approximation of the potential risks involved, inducing far‐reaching conclusions about the need of maintaining the genetic resources of Oriental beech for a species' capacity to cope with environmental change.