Understanding genetic diversity of relict forests. Linking long-term isolation legacies and current habitat fragmentation in Abies pinsapo Boiss

FOREST ECOLOGY AND MANAGEMENT

卷:461

Article

Cobo-Simon, Irene^1,2  Mendez-Cea, Belen²  Jump, Alistair S.³  Seco, Jose¹  Javier Gallego, Francisco²  Carlos Linares, Juan¹ 

[1] Univ Pablo de Olavide, Dept Sistemas Fis Quim & Nat, Seville 41013, Spain

[2] Univ Complutense Madrid, Fac CC Biol, Dept Genet Fisiol & Microbiol, Unidad Genet, E-28040 Madrid, Spain

[3] Univ Stirling, Fac Nat Sci, Biol & Environm Sci, Stirling FK9 4LA, Scotland

关键词: Land-use legacy;    Adaptive management;    Circum-mediterranean firs;    Conservation genetics;    Microsatellite marker;    Genetic diversity;    Genetic differentiation;    Population genetics;   

DOI  :  10.1016/j.foreco.2020.117947

来源: Elsevier

【 摘 要 】

Increasing variability and uncertainty regarding future climate provide new challenges for the conservation of endangered tree species. For example, threat status can be impacted by genetic diversity, where forest trees show reduced geographic range size, isolated populations and fragmented distribution. We place the conservation insights of population genetic structure in a climate change context, using as experimental system a relict drought-sensitive fir (Abies pinsapo Boiss.). Nuclear (nSSR, ISSR) and chloroplast (cpSSR) markers were analysed to investigate the extent to that A. pinsapo evidences ongoing genetic erosion, isolation and divergent genetic diversity, among populations, elevations and cohorts (young, adult and old trees). We obtained contrasting patterns among chloroplast and nuclear markers. Based on cpSSRs, the highest genetic distances were found in the western portion of the distribution, while based on both nSSRs and ISSRs, differentiation appeared in the eastern portion of the distribution. Evidence for bottlenecks and genetic drift were found in all the studied populations, as well as low among-population genetic differentiation. Land use legacies e.g. impacting current forest structural diversity might be related to observed genetic diversity. No evidence of demographic genetic erosion among cohorts were found. Conservation efforts should focus on reducing the probability of occurrence of stochastic events such as fires and habitat loss due to human impacts or climate change to maximise A. pinsapo population sizes. Further research on adaptive potential should focus on identifying active genetic management strategies that might improve adaptation to future climates in such endangered relict species.

【 授权许可】

Free