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Population Genomics of a Cosmopolitan Weed Provides Insights Into Its Local Adaptation and Recent Demographic HistoryNARA Subscribed
Invasive plant species present a growing ecological and economic challenge, and often adapt rapidly to their novel environments through complex demographic and evolutionary processes. Invasion genomics offers powerful tools to disentangle these processes, but most studies rely on geographically narrow sampling across native and non‐native ranges. Erigeron canadensis is a cosmopolitan weed native to North America that has succe...
Widespread Shrubification on European Mountain SummitsNARA Subscribed
Shrubs are expanding across the cold ecosystems of our planet with potentially profound consequences for their biodiversity and functioning. However, evidence is still strongly biased towards the Arctic tundra, while a large‐scale assessment of shrub expansion in alpine areas above the elevational treeline is missing so far. Here we quantified shrub cover changes over the past two decades in 576 permanent plots of 1 m 2 spread...
Coral reef development is influenced by a wide variety of factors, including temperature, salinity, nutrient concentrations, and carbonate chemistry. Studies focusing on physicochemical drivers of coral reef distribution and composition in the Eastern Tropical Pacific (ETP) are scarce, and carbonate chemistry and nutrient data for this region are limited. This study measured coral reef composition and physicochemical parameter...
Molecular Footprints of Quaternary Climate Fluctuations in the Circumpolar Tundra Shrub Dwarf BirchNARA Subscribed
The Arctic tundra biome is undergoing rapid shrub expansion (‘shrubification’) in response to anthropogenic climate change. During the previous ~2.6 million years, glacial cycles caused substantial shifts in Arctic vegetation, leading to changes in species' distributions, abundance and connectivity, which have left lasting impacts on the genetic structure of modern populations. Examining how shrubs responded to past climate ch...
Biogeographic Patterns of Soil Microbial Biomass in Alpine Ecosystems Depend on Local Rather Than Regional DriversNARA Subscribed
Aim Conflicting distribution patterns of soil microbes along the elevation gradient in alpine ecosystems have been suggested based on observations from individual mountains. There remains a lack of biogeographical studies spanning multiple latitudes and climate zones, a scale appropriate to reveal general ecological patterns of soil microbial biomass (SMB) for alpine ecosystems. We conducted a large‐scale sampling campaign alo...
Growth dynamics and climate sensitivities in alpine cushion plants: insights from Silene acaulis in the Swiss AlpsNARA Subscribed
Understanding alpine plants’ growth dynamics and responses to warming is essential for predicting climate change impacts on mountain ecosystems. Here, we examine growth determinants in the alpine cushion plant Silene acaulis in the Swiss Alps, exploring ontogeny, elevation, and climate influences. We collected 40 Silene individuals and 159 individuals from 38 co-occurring alpine species across 2200–3130 m elevations in the Swi...
Motivation Here, we make available a second version of the BioTIME database, which compiles records of abundance estimates for species in sample events of ecological assemblages through time. The updated version expands version 1.0 of the database by doubling the number of studies and includes substantial additional curation to the taxonomic accuracy of the records, as well as the metadata. Moreover, we now provide an R packag...
Long‐term phenological data in alpine regions are often limited to a few locations and thus, little is known about climate‐change‐induced plant phenological shifts above the treeline. Because plant growth initiation in seasonally snow‐covered regions is largely driven by snowmelt timing and local temperature, it is essential to simultaneously track phenological shifts, snowmelt, and near‐ground temperatures. In this study, we...
Tundra Vegetation Community Type, Not Microclimate, Controls Asynchrony of Above‐ and Below‐Ground PhenologyNARA Subscribed
The below‐ground growing season often extends beyond the above‐ground growing season in tundra ecosystems and as the climate warms, shifts in growing seasons are expected. However, we do not yet know to what extent, when and where asynchrony in above‐ and below‐ground phenology occurs and whether variation is driven by local vegetation communities or spatial variation in microclimate. Here, we combined above‐ and below‐ground...
Synchrony and Tail‐Dependent Synchrony Have Different Effects on Stability of Terrestrial and Freshwater CommunitiesNARA Subscribed
Aim Global change can impact the stability of biological communities by affecting species richness and synchrony. While most studies focus on terrestrial ecosystems, our research includes both terrestrial and aquatic realms. Previous works measure overall community synchrony as co‐variation among co‐occurring species, ignoring the tail dependence—when species fluctuate together at extreme abundance levels. We used community ti...
Linking human impacts to community processes in terrestrial and freshwater ecosystemsNARA Subscribed
Human impacts such as habitat loss, climate change and biological invasions are radically altering biodiversity, with greater effects projected into the future. Evidence suggests human impacts may differ substantially between terrestrial and freshwater ecosystems, but the reasons for these differences are poorly understood. We propose an integrative approach to explain these differences by linking impacts to four fundamental p...
Background Walking is the preferred therapy for peripheral arterial disease in early stage. An effect of walking exercise is the increase of blood flow and fluid shear stress, leading, triggered by arteriogenesis, to the formation of collateral blood vessels. Circulating micro-RNA may act as an important information transmitter in this process. We investigated the acute effects of a single bout of 1) aerobic walking with moder...
Global maps of soil temperatureNARA Subscribed
Research in global change ecology relies heavily on global climatic grids derived from estimates of air temperature in open areas at around 2 m above the ground. These climatic grids do not reflect conditions below vegetation canopies and near the ground surface, where critical ecosystem functions occur and most terrestrial species reside. Here, we provide global maps of soil temperature and bioclimatic variables at a 1‐km 2 r...
Species turnover is ubiquitous. However, it remains unknown whether certain types of species are consistently gained or lost across different habitats. Here, we analysed the trajectories of 1827 plant species over time intervals of up to 78 years at 141 sites across mountain summits, forests, and lowland grasslands in Europe. We found, albeit with relatively small effect sizes, displacements of smaller‐ by larger‐ranged specie...
Purpose Physical activity is associated with altered levels of circulating microRNAs (ci-miRNAs). Changes in miRNA expression have great potential to modulate biological pathways of skeletal muscle hypertrophy and metabolism. This study was designed to determine whether the profile of ci-miRNAs is altered after different approaches of endurance exercise. Methods Eighteen healthy volunteers (aged 24 ± 3 years) participated this...
A common soil temperature threshold for the upper limit of alpine grasslands in European mountainsNARA Subscribed
While climatic research about treeline has a long history, the climatic conditions corresponding to the upper limit of closed alpine grasslands remain poorly understood. Here, we propose a climatic definition for this limit, the ‘grassline’, in analogy to the treeline, which is based on the growing season length and the soil temperature. Eighty-seven mountain summits across ten European mountain ranges, covering three biomes (...
SoilTemp: A global database of near‐surface temperatureNARA Subscribed
Current analyses and predictions of spatially explicit patterns and processes in ecology most often rely on climate data interpolated from standardized weather stations. This interpolated climate data represents long‐term average thermal conditions at coarse spatial resolutions only. Hence, many climate‐forcing factors that operate at fine spatiotemporal resolutions are overlooked. This is particularly important in relation to...
Motivation The Tundra Trait Team (TTT) database includes field‐based measurements of key traits related to plant form and function at multiple sites across the tundra biome. This dataset can be used to address theoretical questions about plant strategy and trade‐offs, trait–environment relationships and environmental filtering, and trait variation across spatial scales, to validate satellite data, and to inform Earth system mo...
Motivation The BioTIME database contains raw data on species identities and abundances in ecological assemblages through time. These data enable users to calculate temporal trends in biodiversity within and amongst assemblages using a broad range of metrics. BioTIME is being developed as a community‐led open‐source database of biodiversity time series. Our goal is to accelerate and facilitate quantitative analysis of temporal...
Greater temperature sensitivity of plant phenology at colder sites: implications for convergence across northern latitudesNARA Subscribed
Warmer temperatures are accelerating the phenology of organisms around the world. Temperature sensitivity of phenology might be greater in colder, higher latitude sites than in warmer regions, in part because small changes in temperature constitute greater relative changes in thermal balance at colder sites. To test this hypothesis, we examined up to 20 years of phenology data for 47 tundra plant species at 18 high‐latitude si...
Soil warming opens the nitrogen cycle at the alpine treelineNARA Subscribed
Climate warming may alter ecosystem nitrogen (N) cycling by accelerating N transformations in the soil, and changes may be especially pronounced in cold regions characterized by N‐poor ecosystems. We investigated N dynamics across the plant–soil continuum during 6 years of experimental soil warming (2007–2012; +4 °C) at a Swiss high‐elevation treeline site (Stillberg, Davos; 2180 m a.s.l.) featuring Larix decidua and Pinus unc...