The Limited Legacy of Post-Glacial Recolonization in the Floristic Patterns of the European Alps

Compared to species turnover, patterns of phylogenetic turnover provide extra information about the spatial structure of biodiversity, for example providing more informative comparisons between the biota of sites which share no species. To harness this information for broad‐scale spatial analysis, we present phylo‐GDM, a technique for interpolating the spatial structure of phylogenetic turnover between sampled locations in relation to environment, based on generalised dissimilarity modelling (GDM).Using a database of over 150 000 location records for 114 myobatrachid frog species in Australia, linked to a species‐level phylogeny inferred from 2467 base pairs of mitochondrial DNA, we calculated species and phylogenetic turnover between pairs of sites. We show how phylogenetic turnover extended the range of informative comparison of compositional turnover to more biologically and environmentally dissimilar sites. We generated GDM models which predict species and phylogenetic turnover across Australia, and tested the fit of models for different ages within the phylogeny to find the phylogenetic tree depth at which the relationship to current day environment is greatest. We also incorporated explanatory variables based on biogeographic patterns, to represent broad‐scale turnover resulting from divergent evolutionary histories. We found that while the predictive power of our models was lower for full phylogenetic turnover than for species turnover, models based on the more recent components of the phylogeny (closer to the tips) outperformed species models and full phylogenetic models.Phylo‐GDM has considerable potential as a method for incorporating phylogenetic relationships into biodiversity analyses in ways not previously possible. Because phylogenies do not require named taxa, phylo‐GDM may also provide a means of including lineages with poorly resolved taxonomy (e.g. from metagenomic sequencing) into biodiversity planning and phylogeographic analysis.

The analysis of regional scale patterns of diversity allows insights into the processes that have shaped modern biodiversity at the macro‐scale. Previous analyses studying biogeographic regionalisation across different high‐level taxa have shown similar trends at a global scale. However, incorporating phylogenetic methods when comparing biogeographic regionalisation between subgroups facilitates identification of mechanisms leading to the biogeographic distribution of specific taxa. We analysed the spatial trends of phylogenetic diversity and phylogenetic endemism of 325 species of New World bats, using updated range maps of the modern distributions. These analyses showed phylogeographic signals that reflect the different evolutionary histories of these families. Zoogeographical zones were detected based on range‐weighted phylogenetic turnover. Values of high phylogenetic diversity and endemism were distributed differently across families, suggesting niche conservatism, but a general latitudinal trend of diversity was evident across taxa. Overall, two main bioregions were shared across New World bat taxa (Nearctic and Neotropical), with two additional subregions (Andean and La Platan). We found strong support for an additional transitional zone in the Pacific coast of South America for Emballonuridae and Molossidae. Differences in regionalisation across families indicate that niche conservatism, in situ diversification and dispersal ability are major drivers for the regionalisation of New World bats, within a dual‐centre of diversification scenario. We also found strong inter‐familial support for an independent Caribbean biogeographic region.

AimRange shift is a relatively well‐understood response to climate change, but our ability to predict shifts is limited. Two factors that may cause variation in range shifts across species are dispersal ability and varying rates of climate change through time and across space. Here, we assess patterns of range shifts during the late Quaternary and estimate how the velocity of climate change and the dispersal ability of a species affect the magnitude of species range shifts in response to climate change.LocationNorth America.MethodsWe hindcast species distribution models for 122 North American mammals to five times over the past 17,000 years and forecast them to two future times given two emissions scenarios. Generalized additive models were constructed to quantify the importance of dispersal ability and the velocity of temperature and precipitation in determining the magnitude of range shift expected for individual species.ResultsHindcasted and forecasted ranges demonstrate the variety of responses to climate change. In general, species shifted their ranges in a northerly direction (NW, N, NE) regardless of the type of climate change (i.e., warming vs. cooling). The highest rates of range shifts during the past occurred during periods of relatively rapid climate change (Last Glacial Maximum/Bølling‐Allerød and Bølling‐Allerød/Younger Dryas transitions). Rates of range shifts for the future are projected to be significantly higher than any of the past intervals. The velocity of climate change is significantly associated with the magnitude of range shifts during climate transitions that occur over longer time‐scales, while maximum dispersal distance is important during periods of rapid climate change.Main ConclusionsOur results suggest that both the dispersal ability and the velocity of climate change are significantly associated with species’ range shifts. However, the importance of these two factors is context‐dependent and depends on the interaction of the rate of climate change and the length of time over which the change occurs.

AimCross‐taxonomic congruence in biodiversity patterns is key to understanding the main drivers of community structure, for biogeographical regionalization and to guide conservation. We aim to map the patterns of phylogenetic turnover and disentangle the geographical and environmental factors that drive the phylogenetic composition of distinct faunal assemblages.LocationThe Cerrado savannas of South America.TaxaReptiles and amphibians.MethodsWe measured the proportion of phylogenetic branches shared among sites (i.e. phylogenetic turnover) using presence‐absence matrices for all species in the Cerrado and for endemics only, including only well‐sampled localities from previously compiled inventories. We then tested whether phylogenetic turnover is different from null expectations based on taxonomic turnover. We used generalized dissimilarity modelling (GDM) to test whether geography, topography, soil or climate best explain phylogenetic turnover. Finally, we mapped the observed and the GDM‐predicted clustering of phylogenetic turnover to assess geographical congruence between reptiles and amphibians.ResultsFor all reptiles, geographical distance is the most important factor explaining phylogenetic turnover, whereas for endemic reptiles and amphibians, in general, a set of climatic variables and relief roughness are more important. We did not find any significant correlation between the phylogenetic turnover of reptiles and amphibians, as evidenced by non‐congruent phylogenetic clustering and by different responses to geographical and environmental gradients.Main conclusionsThe different relationships of phylogenetic turnover of reptiles and amphibians to geographical and environmental distances have ultimately shaped the phylogenetic regionalization of these two groups. This incongruence indicates the differential importance of niche filtering, dispersal limitation and the influence of neighbouring biomes in the regionalization of different groups of organisms. Therefore, diversity patterns of one group should ideally not be used as a surrogate to map general patterns or to understand the drivers of diversity of other co‐occurring groups. Thus, conservation efforts need to be designed and implemented for each organismal group.

Influence of climate stability on endemism of the vascular plants of the Chihuahuan Desert

Recent climate warming has been much faster in the Arctic than in the rest of the world, and is expected to accelerate in the future. These rapid changes will affect arctic biodiversity, threaten certain species and shift their distribution ranges. With a focus on dispersal abilities, we here aim to better understand the dynamics of plant species distributions over the next century, and how these changes may impact the composition and distribution of biomes across the terrestrial Arctic. We developed climate-driven species distribution models (SDM) to predict the emerging climate niches for 1174 plant species under different climate scenarios. The model was parameterized using field observations stored in the Global Biodiversity Information Facility database (GBIF) and temperature and bioclimatic variables from the CHELSA climate data set. Trait-based dispersal rates were assigned to each species according to Lososová et al. (2023) and were implemented and used to predict future habitat with a distance-based probability over time. Our results indicated that given the dispersal constraints, only 15 % of the emerging climate niche would be in reach for colonization of plant species until 2100. Characteristic “boreal forest”-biomes were predicted to gain area while the "tundra"-biome became squeezed between the “boreal forest”-biomes and the sea. The “Palearctic boreal forest”-biome was predicted to colonize more area while the "Nearctic boreal forest"-biome showed the largest spatial displacement to the north. The species composition of the vegetation biomes was predicted to change over time and habitat suitability declined overall. We find that the response of arctic plant species to climate change is not simply a straight migration towards the north but rather a complex interaction of different mechanisms leading to altered distribution ranges. The differences in species’ dispersal abilities could lead to compositional changes within the biomes, which can subsequently result in biome shifts from tundra to boreal forest. Extinction lag and establishment lag might substantially delay the predicted range shifts. For future studies, we recommend to include dispersal constraints as we could show that they substantially impact species distributions.

Alpine riverine ecosystems are highly sensitive to climate change and anthropogenic pressures, yet they provide critical ecosystem services, including downstream water resources. Glacier-fed streams, such as the Saldur/Saldura stream in the Italian Central-Eastern Alps, are particularly vulnerable due to their dependence on snow and glacier melt. The Saldur/Saldura catchment (ca. 100 km²), one of the driest areas of the Alps and part of an LTSER platform, is a unique study area due to its dry conditions, low anthropogenic stressors, and the presence of a glacier that sustains the hydrology of this inner-Alpine valley. Since 2010, a long-term biomonitoring program has been assessing the effects of climate and anthropogenic factors - specifically the construction of a small run-of-river (ROR) hydropower plant in 2015 - on stream macroinvertebrate communities. Monthly monitoring during the snow-free period (April-September/October) was initially conducted at three altitudinal sampling sites and was expanded to six sites after the construction of the ROR hydropower plant. This high-resolution temporal dataset allowed us to analyse the spatial and temporal dynamics of macroinvertebrate assemblages in response to natural and anthropogenic drivers. Our findings provide insights into the key dynamics shaping macroinvertebrate communities, highlighting the predominant influence of seasonal melting processes driven by snow and glacier dynamics on their structural and taxonomic characteristics. Increased runoff during peak melt periods corresponds to a decrease in faunal density, taxa richness and functional diversity. Longitudinal gradients also emerged, with taxa distribution patterns reflecting variations in temperature, discharge, and suspended sediment load along the stream. We also observed that seasonal glacial melt dynamics appeared to overshadow the potential impacts of hydropower operations, suggesting that the Saldur/Saldura stream's hydrology and benthic communities remain primarily shaped by climatic drivers. This study highlights the value of long-term, high-resolution monitoring in disentangling the complex interplay between natural processes and anthropogenic factors in sensitive Alpine ecosystems. By combining long-term biomonitoring approaches with advanced statistical analyses, our work demonstrates the resilience of glacier-fed stream macroinvertebrate communities to localised human impacts, while emphasising their vulnerability to climate-induced changes in glacier and snowmelt dynamics. The results contribute to a broader understanding of the ecological implications of small hydropower plants in low-impacted valleys and highlight the importance of sustained monitoring efforts for effective management, conservation and future water scarcity scenarios in Alpine regions.

BackgroundWildfires play a key role in shaping Mediterranean landscapes and ecosystems and in impacting species dynamics. Numerous studies have investigated the wildfire occurrences and the influence of their drivers in many countries of the Mediterranean Basin. However, in this regard, no studies have attempted to compare different Mediterranean regions, which may appear similar under many aspects. In response to this gap, climatic, topographic, anthropic, and landscape drivers were analyzed and compared to assess the patterns of fire ignition points in terms of fire occurrence and frequency in Catalonia (Spain), Sardinia, and Apulia (Italy). Therefore, the objectives of the study were to (1) assess fire ignition occurrence in terms of probability and frequency, (2) compare the main drivers affecting fire occurrence, and (3) produce fire probability and frequency maps for each region.ResultsIn pursuit of the above, the probability of fire ignition occurrence and frequency was mapped using Negative Binomial Hurdle models, while the models’ performances were evaluated using several metrics (AUC, prediction accuracy, RMSE, and the Pearson correlation coefficient). The results showed an inverse correlation between distance from infrastructures (i.e., urban roads and areas) and the occurrence of fires in all three study regions. This relationship became more significant when the frequency of fire ignition points was assessed. Moreover, a positive correlation was found between fire occurrence and landscape drivers according to region. The land cover classes more significantly affected were forest, agriculture, and grassland for Catalonia, Sardinia, and Apulia, respectively.ConclusionsCompared to the climatic, topographic, and landscape drivers, anthropic activity significantly influences fire ignition and frequency in all three regions. When the distance from urban roads and areas decreases, the probability of fire ignition occurrence and frequency increases. Consequently, it is essential to implement long- to medium-term intervention plans to reduce the proximity between potential ignition points and fuels. In this perspective, the present study provides an applicable decision-making tool to improve wildfire prevention strategies at the European level in an area like the Mediterranean Basin where a profuse number of wildfires take place.

The separate and combined effects of different drivers of change to water fluxes and resources on land (CWOL) remain difficult to distinguish and largely unknown, particularly at a global scale. Our study analyzes CWOL during the period 1901–2008, based on available hydroclimatic data for up to 859 hydrological basins. We develop a worldwide spectrum of change magnitudes and directions in Budyko space, from which we distinguish climate and landscape drivers of CWOL. We find that landscape drivers (e.g., changes in land and water use, water storage or water phase) are needed to explain CWOL in at least 74% of the basins studied. The water change effects of such landscape drivers are mostly opposite to those of atmospheric climate change. The change spectrum approach we developed provides a useful tool for quantifying and visualizing CWOL and for distinguishing the effects of climate and landscape drivers across regions and scales.

Climate change generally requires species to migrate northward or to higher elevation to maintain constant climate conditions, but migration requirement and migration capacity of individual species can vary greatly. Individual populations of species occupy different positions in the landscape that determine their required range shift to maintain similar climate, and likewise the migration capacity depends on habitat connectivity. Here, we demonstrate an approach to quantifying species vulnerabilities to climate change for 419 rare vascular plants in Alberta, Canada, based on a multivariate velocity of climate change metric, local habitat fragmentation, and migration capacity. Climate change velocities indicated that future migration requirements ranged from 1 to 5 km/year in topographically complex landscapes, such as the Alberta Foothills and Rocky Mountains. In contrast, migration requirements to maintain constant climate in relatively flat Boreal Plains, Parkland, and Grassland ranged from 4 to 8 km/year. Habitat fragmentation was also highest in these flat regions, particularly the Parkland Natural Region. Of the 419 rare vascular plants assessed, 36 were globally threatened (G1–G3 ranking). Three globally threatened species were ranked as extremely vulnerable and five species as highly vulnerable to the interactions among climate change velocity, habitat fragmentation, and migration capacity. Incorporating dispersal characteristics and habitat fragmentation with local patterns in climate change velocity improves the assessment of climate change threats to species and may be applied to guide monitoring efforts or conservation actions.

Epiphytic communities offer an original framework to disentangle the contributions of environmental filters, biotic interactions and dispersal limitations to community structure at fine spatial scales. We determine here whether variations in light, microclimatic conditions and host tree size affect the variation in species composition and phylogenetic structure of epiphytic bryophyte communities, and hence, assess the contribution of environmental filtering, phylogenetic constraints and competition to community assembly. A canopy crane giving access to 1.1 ha of tropical rainforest in Yunnan (China) was employed to record hourly light and microclimatic conditions from 54 dataloggers and epiphytic bryophyte communities from 408 plots. Generalized Dissimilarity Modelling was implemented to analyse the relationship between taxonomic and phylogenetic turnover among epiphytic communities, host‐tree characteristics and microclimatic variation. Within‐tree vertical turnover of bryophyte communities was significantly about 30% higher than horizontal turnover among‐trees. Thus, the sharp vertical variations in microclimatic conditions from tree base to canopy are more important than differences in age, reflecting the likelihood of colonization, area, and habitat conditions between young and old trees, in shaping the composition of epiphytic bryophyte communities. Our models, to which microclimatic factors contributed most (83–98%), accounted for 33% and 18% of the variation in vertical turnover in mosses and liverworts, respectively. Phylogenetic turnover shifted from significantly negative or non‐significant within communities to significantly positive among communities, and was slightly, but significantly, correlated with microclimatic variation. These patterns highlight the crucial role of microclimates in determining the composition and phylogenetic structure of epiphytic communities. Synthesis. The mostly non‐significant phylogenetic turnover observed within communities does not support the idea that competition plays an important role in epiphytic bryophytes. Instead, microclimatic variation is the main driver of community composition and phylogenetic structure, evidencing the role of phylogenetic niche conservatism in community assembly.

Summary Understanding changes of biodiversity across the landscape underlies biogeography and ecology and is important in land management and conservation. Measures of species and phylogenetic turnover used to estimate the rate of change of assemblages between sets of locations are more often influenced by wide‐ranging taxa. Transition zones between regions that are associated with range‐restricted taxa can be obscured by wide‐ranging taxa that span them. We present a set of new range‐weighted metrics of taxon and phylogenetic turnover, as modifications of conventional metrics, where the range‐restricted components of the assemblages are assigned greater weight in the calculations. We show how these metrics are derived from weighted endemism and phylogenetic endemism and demonstrate their properties using a continent‐wide data set of Australian Acacia. The range‐weighted metrics result in better delineated transition zones between regions, in that the rate of turnover is steeper than with conventional turnover measures. These metrics provide important complementary information for the interpretation of spatial turnover patterns derived from conventional turnover metrics. Additionally, the phylogenetic variant incorporates information about phylogenetic relatedness while also not saturating at high values of turnover, thus remaining useful for comparisons over greater distances than conventional turnover metrics.

Soil, climate, and landscape drivers of base cation concentrations in green stormwater infrastructure soils

Overview: An Outline of Europe's Alpine Areas.- A Bioclimatic Characterisation of Europe's Alpine Areas.- The High Mountain Vegetation of: the Scandes.- The High Mountain Vegetation of Scotland.- Vegetation of the Giant Mountains, Central Europe.- The Alpine Vegetation of the Alps.- The Alpine Flora and Vegetation of the South-Eastern Carpathians.- The High Mountain Flora and Vegetation of the Apennines and the Italian Alps.- The Vegetation of the Alpine Zone in the Pyrenees.- High Mountain Vegetation of the Caucasus Region.- The Vegetation of the Corsican High Mountains.- The High Mountain Vegetation of the Balkan Peninsula.- Overview: Patterns in Diversity.- TAxonomic Diversity of Vascular Plants in the European Alpine Areas.- Patterns in the Plant Species Richness of European High Mountain Vegetation.- Altitude Ranges and Spatial Patterns of Alpine Plants in Northern Europe.- Vascular Plant and Bryophyte Diversity Along Elevational Gradients in the Alps.- Assessing the Long-term Dynamics of Endemic Plants at Summit Habitats.- Mapping Alpine Vegetation.- A GIS Assessment of Alpine Biodiversity at a Range of Scales.- Overview: Invertebrate Diversity in Europe's Alpine Regions.- The Geographical Distribution of High Mountain Macrolepidoptera in Europe.- High Altitude Invertebrate Diversity in the Ural Mountains.- The Diversity of High Altitude Arachnids (Araneae. Opiliones, Pseudoscorpiones) in the Alps.- Patterns of Butterfly Diversity Above the Timberline in the Italian Alps and Apennines.- Diversity Patterns of Carabids in the Alps and the Apennines.- Overview: Alpine Vertebrates.- Breeding Bird Assemblages and Habitat Use of Alpine Areas in Scotland.- Rodents in the European Alps: Population Ecology and Potential Impacts on Ecosystems.- Large Herbivores in Continental European Alpine Ecosystems: Current Status and Challenges for the Future.- Diversity of Alpine Vertebrates in the Pyrenees and Sierra Nevada, Spain.- The Impacts of Vertebrate Grazers onVegetation in Eurpean High Mountains.- Overview: Alpine Vegetation Dynamics and Climate Change - a Synthesis of Long-term Studies and Observations.- Long-term Changes in Alpine Plant Communities in Norway and Finland.- Vegetation Dynamcis at the Treeline Ecotone in the Ural Highlands, Russia.- Recent Increases in Summit Flora Caused by Warming in the Alps.- The Piz Linard - Europe's Oldest Mountain Vegetation Study Site.- Alpine Biodiversity in Space and Time: A Synthesis

Island systems have long played a central role in the development of ecology and evolutionary biology. However, while many empirical studies suggest species differ in vital biogeographic rates, such as dispersal abilities, quantitative methods have had difficulty incorporating such differences into analyses of whole‐assemblages. In particular, differences in dispersal abilities among species can cause variation in the spatial clustering and localization of species distributions. Here, we develop a single, hierarchical Bayes, assemblage‐wide model of 252 bird species distributions on the islands of northern Melanesia and use it to investigate a) whether dispersal limitation structures bird assemblages across the archipelago, b) whether species differ in dispersal ability, and c) test the hypothesis that wing aspect ratio, a trait linked to flight efficiency, predicts differences inferred by the model. Consistent with island biogeographic theory, we found that individual species were more likely to occur on islands with greater area, and on islands near to other islands where the species also occurred. However, species showed wide variation in the importance and spatial scale of these clustering effects. The importance of clustering in distributions was greater for species with low wing aspect ratios, and the spatial scale of clustering was also smaller for low aspect ratio species. These findings suggest that the spatial configuration of islands interacts with species dispersal ability to affect contemporary distributions, and that these species differences are detectable in occurrence patterns. More generally, our study demonstrates a quantitative, hierarchical approach that can be used to model the influence of dispersal heterogeneity in diverse assemblages and test hypotheses for how traits drive dispersal differences, providing a framework for deconstructing ecological assemblages and their drivers.