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Florian Zellweger David Coomes Jonathan Lenoir Leen Depauw Sybryn L. Maes Monika Wulf Keith J. Kirby Jrg Brunet Martin Kopecký Frantiek Mli Wolfgang Schmidt Steffi Heinrichs Jan den Ouden Bogdan Jaroszewicz Gauthier Buyse Fabien Spicher Kris Verheyen Pieter De Frenne 《Global Ecology and Biogeography》2019,28(12):1774-1786
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Jacqueline S. Lima Liliana Ballesteros‐Mejia Matheus S. Lima‐Ribeiro Rosane G. Collevatti 《Global Change Biology》2017,23(11):4639-4650
The high rates of future climatic changes, compared with the rates reported for past changes, may hamper species adaptation to new climates or the tracking of suitable conditions, resulting in significant loss of genetic diversity. Trees are dominant species in many biomes and because they are long‐lived, they may not be able to cope with ongoing climatic changes. Here, we coupled ecological niche modelling (ENM) and genetic simulations to forecast the effects of climatic changes on the genetic diversity and the structure of genetic clusters. Genetic simulations were conditioned to climatic variables and restricted to plant dispersal and establishment. We used a Neotropical savanna tree as species model that shows a preference for hot and drier climates, but with low temperature seasonality. The ENM predicts a decreasing range size along the more severe future climatic scenario. Additionally, genetic diversity and allelic richness also decrease with range retraction and climatic genetic clusters are lost for both future scenarios, which will lead genetic variability to homogenize throughout the landscape. Besides, climatic genetic clusters will spatially reconfigure on the landscape following displacements of climatic conditions. Our findings indicate that climate change effects will challenge population adaptation to new environmental conditions because of the displacement of genetic ancestry clusters from their optimal conditions. 相似文献
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S. Dewan P. De Frenne O. Leroux I. Nijs K. Vander Mijnsbrugge K. Verheyen 《Plant biology (Stuttgart, Germany)》2020,22(Z1):113-122
- Plants are known to respond to warming temperatures. Few studies, however, have included the temperature experienced by the parent plant in the experimental design, in spite of the importance of this factor for population dynamics.
- We investigated the phenological and growth responses of seedlings of two key temperate tree species (Fagus sylvatica and Quercus robur) to spatiotemporal temperature variation during the reproductive period (parental generation) and experimental warming of the offspring. To this end, we sampled oak and beech seedlings of different ages (1–5 years) from isolated mother trees and planted the seedlings in a common garden.
- Warming of the seedlings advanced bud burst in both species. In oak seedlings, higher temperatures experienced by mother trees during the reproductive period delayed bud burst in control conditions, but advanced bud burst in heated seedlings. In beech seedlings, bud burst timing advanced both with increasing temperatures during the reproductive period of the parents and with experimental warming of the seedlings. Relative diameter growth was enhanced in control oak seedlings but decreased with warming when the mother plant experienced higher temperatures during the reproductive period.
- Overall, oak displayed more plastic responses to temperatures than beech. Our results emphasise that temperature during the reproductive period can be a potential determinant of tree responses to climate change.
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Populations at the edge of species distributions are especially vulnerable to climate change. Genetic changes as well as modification of their population structure are expected as reactions to global warming. Atlantic salmon ( Salmo salar ) inhabiting south France has been chosen as a model for studying the effect of global warming in marginal populations during the last 15 years. Increased gene flow between neighboring populations and dichotomy of maturation age between sexes have been identified as two main population changes significantly associated with high values of the North Atlantic Oscillation index, a global climate indicator. Although occurrence of isolated populations in each river (or even tributary) is a paradigm for this species, at least in northern areas, increased gene flow between rivers is forecasted as long as climate warming increases, favoring metapopulations at regional level. 相似文献
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O. ROGER ANDERSON 《The Journal of eukaryotic microbiology》2010,57(2):218-219
ABSTRACT. High latitude microbial communities, incurring increased global warming, are a potential major source of respiratory CO2 contributing to an enhanced greenhouse effect. Data on respiration and microbial density are presented for a moist, high tussock site compared with a low, water saturated site. The density of bacteria and eukaryotic microbes was nearly equivalent at both sites and potentially could yield substantial release of respiratory CO2 with continued warming. Respiratory rates for soil from the high site were greater than the low. The Q10 of 2.4 for the high tussock sample was approximately 1.3 × that of the low site sample (Q10 of 1.7). 相似文献