Climate warming may increase the frequency of cold-adapted haplotypes in alpine plants

Modelling of climate-driven range shifts commonly treats species as ecologically homogeneous units. However, many species show intraspecific variation of climatic niches and theory predicts that such variation may lead to counterintuitive eco-evolutionary dynamics. Here, we incorporate assumed intraspecific niche variation into a dynamic range model and explore possible consequences for six high-mountain plant species of the European Alps under scenarios of twenty-first century climate warming. At the species level, the results indicate massive range loss independent of intraspecific variation. At the intraspecific level, the model predicts a decrease in the frequency of warm-adapted haplotypes in five species. The latter effect is probably driven by a combination of leading-edge colonization and priority effects within the species’ elevational range and was weakest when leading-edge expansion was constrained by mountain topography The resulting maladaptation may additionally increase the risk that alpine plants face from shrinkage of their ranges in a warming climate.

Are Temperate Alpine Plants With Distinct Phenology More Vulnerable to Extraordinary Climate Events Than Their Continuously Flowering Relatives in Tropical Mountains?

Alpine plants are perceived as some of the most vulnerable to extinction due to the global climate change. We expected that their life history strategies depend, among others, on the latitude they live in: those growing in temperate regions are likely to have a distinct phenology with short seasonal peaks, while tropical alpine plants can potentially exploit favorable year-round growing conditions and different individuals within a population may flower at different times of the year. In species, whose flowering is synchronized into short seasonal peaks, extraordinary climate events, which may become stronger and more frequent with climate change, can potentially destroy reproductive organs of all synchronized individuals. This may result in reducing fitness or even extinction of such species. We studied field populations of five groups of closely related Andean alpine plant species to test our expectations on their latitude-dependent synchronization of flowering. Our results confirmed these expectations: (i) Tropical alpine species were least synchronized and flowering peaks of different individuals in their populations were distributed across many months. Thus, in tropical alpine species, if an extraordinary event happens, only some individuals are affected and other members of the population successfully reproduce in other parts of the long season. (ii) Higher synchronicity in flowering of temperate and subtropical alpine plants resulted even in some of these species using only a part of the short growing season to reproduce, which increases their vulnerability to extraordinary climatic events. However, we did not find any unique pattern valid for all species, groups and regions. The diversity in flowering phenology (i.e., different levels of seasonality and synchronicity) that we found increases the likelihood of plants successfully coping with climate change.

Not so ancient: Misclassification of alpine plants biases the dating of the evolution of alpine biota in the Himalaya-Tibet Orogen

Ding et al. (Science 2020) proposed that the extant lineages of the alpine flora of the Tibet Himalaya Hengduan region emerged by the early Oligocene. We argue that these results are based on misclassifying high montane taxa as alpine and that their data support alpine habitats only at about 7.5 mio years before present.

Distribution of alpine endemic plants of northern Asia: a dataset

We describe a dataset providing information on the geographic distribution of northern Asian endemic alpine plants. It was obtained by digitising maps from the atlas “Endemic alpine plants of Northern Asia”. Northern Asia includes numerous mountain ranges which may have served as refugia during the Pleistocene ice ages, but there have been no studies that analysed this question. We suggest that this dataset can be applied for better understanding of the alpine endemism in northern Asia. The dataset includes 13709 species distribution records, representing 211 species from 31 families and 106 genera. Each record provides data regarding the distribution of an individual species. These data provide a foundation for studying northern Asia's endemic alpine species and conducting research on the factors concerning their distribution.

Adventitious rooting in response to long-term cold: a possible mechanism of clonal growth in alpine perennials

Arctic alpine species experience extended periods of cold and unpredictable conditions during flowering. Thus, often, alpine plants use both sexual and asexual means of reproduction to maximise fitness and ensure reproductive success. We used the arctic alpine perennial Arabis alpina to explore the role of prolonged cold exposure on adventitious rooting. We exposed plants to 4°C for different durations and scored the presence of adventitious roots on the main stem and axillary branches. Our physiological studies demonstrated that the presence of adventitious roots positively correlates with increased duration of exposure to cold treatment, with 21 weeks at 4 °C saturating the effect of cold on adventitious rooting. On the main stem adventitious roots developed in specific internodes. Transcriptomic and histological studies indicated that adventitious roots in A. alpina stems are initiated during cold exposure and emerge after plants experience growth promoting conditions. The emergence of the adventitious root primordia correlates with an increase in auxin response and free endogenous auxin in the stems. Our results highlight the role of low temperature during clonal growth in alpine plants and provide insights on the molecular mechanisms involved at different stages of adventitious rooting.