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Accueil du site → Doctorat → Espagne → 2021 → Selective pressures of climate change in drought-sensitive relict forests. Genetic responses in Abies pinsapo and Cedrus atlantica to a shifting environment

Universidad Complutense de Madrid (2021)

Selective pressures of climate change in drought-sensitive relict forests. Genetic responses in Abies pinsapo and Cedrus atlantica to a shifting environment

Cobo Simón, Irene

Titre : Selective pressures of climate change in drought-sensitive relict forests. Genetic responses in Abies pinsapo and Cedrus atlantica to a shifting environment

Presiones selectivas del cambio climático sobre bosques relictos sensibles a la sequía. Respuestas genéticas de Abies pinsapo y Cedrus atlantica a un entorno cambiante

Auteur : Cobo Simón, Irene

Université de soutenance : Universidad Complutense de Madrid

Grade : Doctoral Tesis 2021

Résumé
Increasing variability and uncertainty regarding future climate provide new challenges for understanding species adaptive capacity. Trees are especially concerning given their lower evolutionary rates and ecological importance. Thus, the knowledge of their intraspecific genetic diversity is crucial to predict the possible evolutionary consequences of global climate change and its long-term effects on biodiversity. Furthermore, since drought stress is among the first limitations for plants facing a changing climate, understanding the underlying mechanisms involved in drought stress response/resilience in trees constitutes one of the most valuable research objectives in evolutionary ecology. Relict species constitute reliable models given their reduced geographic range size, isolation and usually fragmented distribution, which subject them to many shifting genetic processes. Moreover, despite these theoretically limitant genetic characteristics for adaptation, empirical evidence frequently shows a lack of decreased fitness (Hampe and Jump 2011). A possible explanation can be that many of them originated from populations that overcome the cold stages of the Quaternary. Therefore, they might contain key genetic variants in ecologically relevant traits (Crawford 2008, Kawecki 2008, Hampe and Jump 2011). A particularly interesting group are those that now inhabit at southern locations since they can be potentially preadapted to environmental conditions expected in future in more northerly central areas in the future (Hampe and Petit, 2005). Here, we attempted to test the effect of these processes in the genetic diversity and genetic structure of trees, as well as determining their evolutionary potential under a climate change scenario, by using as experimental models two southern relict and climate changethreatened conifers, located in altitudinal ecotones and sharing a biogeographic origin : the Southernomost european fir (Abies pinsapo Boiss.), endemic to Southern Spain, and the Atlas cedar (Cedrus atlantica), endemic to Northern Morocco...

Mots clés  : Climate change, Drought-sensitive relict forests, Abies pinsapo, Cedrus atlantica ; Cambio climático, Bosques relictos sensibles a la sequía, Abies pinsapo, Cedrus atlantica

Présentation

Page publiée le 11 février 2022