From past to future: impact of climate change on range shifts and genetic diversity patterns of circumboreal plants

Ada Wróblewska,Paweł Mirski

doi:10.1007/s10113-017-1208-3

Abstract

Climate change is projected to influence the genetic resources of plant species. Recent research has examined genetic diversity patterns under current climate conditions, with little attention to the future genetic consequences for species. In this study, we combined ecological niche modeling and population genetic approaches to project future changes in genetic diversity using plastid and nuclear DNA and reconstructed distribution patterns of three circumboreal plants (Chamaedaphne calyculata, Linnaea borealis ssp. borealis, and Pedicularis sceptrum-carolinum ssp. sceptrum-carolinum) in the last glacial maximum. We found that circumboreal plants could potentially lose their geographic ranges in the future (2070; 35–52% in RCP 4.5 (representative concentration pathways), 37–53% in RCP 6.0, and 56–69% in RCP 8.5), only slightly compensated by a predicted range gain of 18–33% (across the three RCPs). It is expected that future genetic diversity level could remain similar or lower than the present level. On the other hand, the homogeneity of the genetic background—a lack of admixture and domination of one gene pool in most populations of C. calyculata and L. borealis ssp. borealis—was predicted to become more pronounced in the future. Combining the paleoecological niche modeling and genetic data revealed, more precisely, the climate refugia for circumboreal plants in the Alps, central Asia, Beringia, and southern North America and the macrorefugia more restricted to the northern part of Eurasia and North America, reaching the arctic zone.

Highlights

Life-history traits, population dynamics, and natural or human impacts have been widely discussed as major determinants of intraspecific genetic diversity (e.g., Loveless and Hamrick 1984; Hamrick and Godt 1989; Barrett and Husband 1990; Young et al 1996; Gitzendanner and Soltis 2000; Nybom 2004; Jump and Peñuelas 2006; Parmesan 2006; Bizoux and Mahy 2007)
Our investigation suggests that the geographic range and genetic diversity patterns of circumboreal plant taxa will respond in different ways under future climate warming
We did not incorporate such features in the ecological niche models (ENMs), leading to overestimation of the future plant distributions as well as to incongruity between the empirical and modeled spatial genetic structures. Despite these uncertainties and the positing of assumptions that can rather increase the putative loss of genetic diversity in species (Alsos et al 2012), our results demonstrate the usefulness of combining ENMs and molecular genetic analyses to forecast spatial patterns of genetic diversity

Summary

Introduction

Life-history traits, population dynamics, and natural or human impacts (e.g., isolation, fragmentation, and climate changes) have been widely discussed as major determinants of intraspecific genetic diversity (e.g., Loveless and Hamrick 1984; Hamrick and Godt 1989; Barrett and Husband 1990; Young et al 1996; Gitzendanner and Soltis 2000; Nybom 2004; Jump and Peñuelas 2006; Parmesan 2006; Bizoux and Mahy 2007). Surveys of genetic diversity under current climate conditions have a rich history in the literature, potential future impacts on the genetic diversity of species are rarely examined (Alsos et al 2009; Thomassen et al 2010; Beatty and Provan 2011; Collevatti et al 2011; Alsos et al 2012; Jay et al 2012; Eidesen et al 2013; Temunovic et al 2013; Steane et al 2014). Northern plant species could be more severely threatened than other species by recent and future climate change (Thuiller et al 2005; Parmesan 2006). Arctic-alpine/alpine species are more sensitive than circumboreal species to potential loss of climatically suitable areas, because they are adapted to colder climates than the latter

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Conclusion