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Intraspecific morphological variation of organisms is known to be influenced by several factors, but the role of habitat availability has been scarcely investigated. Studying bird wing morphology is ideal to explore this topic, given the usually rapid response of birds to environmental changes, but other factors such as sexual dimorphism, habitat structure, climate and elevation need to be considered. Here, we investigated the effects of habitat availability, local climate and elevation on the wing morphology of a high-elevation specialist bird (Montifringilla nivalis), while accounting for sexual dimorphism. We hypothesized that birds relying on less extended suitable areas around their breeding sites show wing traits allowing a more energy-efficient flight, given their need of more frequent and longer movements to find foraging areas in the post-breeding period and the longer dispersal distances. We also expected that individuals breeding at higher elevations show wings traits allowing higher flight efficiency, given the higher hypoxia risk. We derived wing traits (isometric size, pointedness and concavity) by measuring primary feathers of individuals from 7 breeding sites in the European Alps, and we obtained habitat availability from detailed habitat suitability maps. Consistently with the need for a more energy-efficient flight, birds relying on less extended suitable habitat showed larger and more concave wings, and individuals breeding at higher elevations showed more concave wings. Local climate had a less clear effect. The observed patterns may result from local adaptations and could represent one of the ways mountain birds cope with the harsh and unpredictable environment they inhabit.

Aim: To provide the first syntaxonomic, plot-based classification of the dry grasslands and thorn-cushion communities in Armenia. Study area: Armenia. Methods: We sampled 111 vegetation plots (10 m2) and recorded environmental and structural parameters. We collected additional 487 relevés from surrounding countries for a broad-scale comparison. We used modified TWINSPAN to derive a syntaxonomic classification system, whose units were then compared among each other regarding species composition, structure, site conditions and distribution. Results: The classification of Armenian vegetation plots resulted in a 12-cluster solution. Unsupervised classification of the broad-scale dataset yielded five main groups, which were used for the high-level syntaxonomic assignments of the Armenian data. We assigned about half of the plots of the Armenian dataset to the Festuco-Brometea, while the remaining represented a potential new class, preliminarily called “Ziziphora tenuior-Stipa arabica grasslands”. Most of the syntaxa below class level are new to science, therefore we provide formal descriptions of three orders (Plantagini atratae-Bromopsietalia variegatae, Onobrychido transcaucasicae-Stipetalia pulcherrimae, Cousinio brachypterae-Stipetalia arabicae), four alliances (Acantholimono caryophyllacei-Stipion holosericeae, Artemision fragrantis, Onobrychido michauxii-Stipion capillatae, Onobrychido transcaucasicae-Stipion pulcherrimae) and six associations. We found significant differences in the topographic, climatic and soil characteristics, and structural parameters, species life forms and distribution range types between the grassland types at different syntaxonomic levels. The mean species richness was 47.3 (vascular plants: 46.8, bryophytes: 0.4, lichens: 0.1). Conclusions: We found remarkable differences of the Armenian dry grasslands from the previously known units and described most of the higher syntaxa and all the associations as new to science. Our study provides arguments for a potential new class of Ziziphora tenuior-Stipa arabica grasslands separate both from the Euro-Siberian Festuco-Brometea and the Anatolian Astragalo-Brometea. Finally, we found plot scale richness of vascular plants clearly above the Palaearctic average of dry grasslands and that of non-vascular plants clearly below, which calls for further biodiversity analyses. Taxonomic reference: Euro+Med (2023) for vascular plants, Hodgetts et al. (2020) for bryophytes, Nimis et al. (2018) for lichens except for Xanthoparmelia camtschadalis (Ach.) Hale. Abbreviations: EDGG = Eurasian Dry Grassland Group; DCA = detrended correspondence analysis; ICPN = International Code of Phytosociological Nomenclature (Theurillat et al. 2021); TWINSPAN = two-way indicator species analysis.

Der Anbau von Arznei- und Gewürzpflanzen zeichnet sich in der Regel durch vielfältige Anbaukulturen auf relativ kleinen Flächen aus. Dies gilt insbesondere für Südtirol, wo diese Kulturen hauptsächlich von kleinen Betrieben im Berggebiet angebaut werden. Dieser kleinflächige Anbau von Arznei- und Gewürzpflanzen lässt vermuten, dass die Betriebe einen hohen ökologischen Wert haben. Es gibt wenige Studien zur Erfassung der Biodiversität im Anbau von Arznei- und Gewürzpflanzen. Daher wurden in dieser Arbeit Kräuteranbau-Betriebe als Lebensraum für blütenbesuchende Arthropoden untersucht. An drei Untersuchungsstandorten wurden im Jahr 2021 jeweils an drei Terminen Farbschalen zur Sammlung von Arthropoden verwendet. Kräuteranbau-Betriebe stellten sich als ein wertvoller Lebensraum für verschiedene Arthropoden heraus. Insgesamt wurden 12.570 Individuen mit den Farbschalen gesammelt. Insbesondere Wildbienen waren mit 10 % des regionalen Artenpools sehr artenreich. Auch potenzielle Schädlinge, wie zum Beispiel Blattläuse, waren sehr häufig anzutreffen, wobei natürliche Feinde, wie zum Beispiel Parasitoide, ebenfalls zahlreich vertreten waren. Insgesamt können Kräuteranbaubetriebe als strukturreiche Oasen für Arthropoden fungieren und sich somit auf einer breiteren Skala positiv auf die Biodiversität auswirken.

Understanding the main drivers of biodiversity loss in Europe's agricultural landscapes has been a research priority in the last decades. One of the most important factors promoting biodiversity in farmed landscapes is habitat heterogeneity, which has often proved crucial for avian species and communities. Birds are highly sensitive to environmental changes and make use of a broad range of ecological niches, thus being exceptionally sensitive to the loss of habitat heterogeneity. Remote sensing data are particularly suited to quantify habitat heterogeneity at fine scales over relatively large extents, allowing to consider how different measures of heterogeneity may affect biotic communities at a regional scale. Here, we used airborne LiDAR (Light Detection And Ranging) and satellite multispectral data to derive vegetation canopy height and primary productivity for 118 sites in complex agricultural landscapes in a region in the Central Alps. We computed different bird diversity indices and classified bird species into guilds according to specific traits to analyse the relationship between avian communities and different facets of habitat heterogeneity. Results confirmed that habitat heterogeneity is essential in shaping rich and diverse bird communities, and it is particularly important for several farmland birds. By comparing the effects of canopy height, primary productivity, and specific vegetation features (e.g., cover of grassland, shrub, and tree layers), we showed how different habitat characteristics as well as landscape heterogeneity affected bird richness, diversity, functional entropy, and trait patterns. Landscape and height heterogeneity, estimated by NDVI and LiDAR Rao's Q indices, strongly influenced all response variables, for example, high NDVI values promoted species diversity and ground-understory nesters, and shrub layer was important for ground-understory nesters and forest specialists. Finally, we provide recommendations for conservation practices and mitigation measures to improve bird diversity in agricultural landscapes.

Anti-CD20 therapies decrease the humoral response to SARS-CoV-2 immunization. We aimed to determine the extent of the humoral response to SARS-CoV-2 antigens in correlation with peripheral B-cell dynamics among patients with central nervous system inflammatory disorders treated with anti-CD20 medications. We retrospectively included patients receiving anti-CD20 therapy after antigen contact who were divided into responders (>7 binding antibody units (BAU)/mL) and non-responders (n = 34, non-responders n = 37, recall cohort n = 9). The B-cell counts among responders were significantly higher compared to non-responders (mean 1012 cells/µL ± SD 105 vs. mean 17 cells/µL ± SD 47; p < 0.001). Despite very low B-cell counts (mean 9 cells/µL ± SD 20), humoral response was preserved among the recall cohort (mean 1653 BAU/mL ± SD 2250.1) and did not differ significantly from responders (mean 735 BAU/mL ± SD 1529.9; p = 0.14). Our data suggest that peripheral B cells are required to generate antibodies to neo-antigens but not for a recall response during anti-CD20 therapy. Evaluation of B-cell counts and pre-existing SARS-CoV-2 antibodies might serve as biomarkers for estimating the immune competence to mount a humoral response to SARS-CoV-2 antigens.

The morphology of bird wings is subject to a variety of selective pressures, including migration, predation, habitat structure and sexual selection. Variation in wing morphology also occurs at the intraspecific and intrapopulation level, and can be related to sex, age, migration strategy and environmental factors. The relationship between environment and intraspecific variation in wing morphology is still poorly understood. In this work, we studied the relationship between wing morphology and breeding environment in a high‐elevation specialist bird, the water pipit Anthus spinoletta. We calculated wing isometric size, pointedness and convexity of 84 birds mist‐netted at breeding sites in year 2021 in the European Alps. We then searched for associations between these traits and potentially relevant breeding site characteristics (vegetation structure, elevation, latitude). For all wing traits, sex and one or more environmental factors best explained the variation, with environmental factors explaining between 3 and 8% of the variation. Wing size was negatively related to tree cover and wing convexity was negatively related to bush cover. Elevation contributed to explain variation in wing pointedness, but the direction of its effect was unclear. The negative relationship between wing size and tree cover could be due to intraspecific competition, i.e. to the relegation of smaller winged low‐quality individuals in marginal grassland areas. Higher wing convexity could improve predator escape ability in areas with scarce protecting vegetation, with possible effects on habitat choice. These findings represent one of the few demonstrated cases of wing morphology–environment relationships at the intraspecific level.

Mountain ecosystems play an important role globally as centers of biodiversity and in providing ecosystem services to lowland populations, but are influenced by multiple global change drivers such as climate change, nitrogen deposition, or altered disturbance regimes. As global change is accelerating and the consequences for humans and nature are intensifying, there is an increasing demand for understanding and predicting the impacts and implications of global change on mountain ecosystems. Manipulation experiments are one of the major tools for testing the causal impacts of global change and establishing a mechanistic understanding of how these changes may transform the global biota from single organisms to entire ecosystems. Over the past three decades, hundreds of such experiments have been conducted in mountainous regions worldwide. To strengthen the experimental evidence for the possible ecological consequences of global change, we systematically reviewed the literature on global change experiments in mountains. We first investigated the spread of manipulation experiments to test the effects of different global change drivers on key biological and ecological processes from the organism to the ecosystem level. We then examined and discussed the balance of evidence regarding the impact of these global change drivers on biological and ecological processes, and outlined the possible consequences for mountain ecosystems. Finally, we identified research gaps and proposed future directions for global change research in mountain environments. Among the major drivers, temperature was manipulated most frequently, generally showing consistent strong impacts between biological and ecosystem processes, functional groups, and habitat types. There is also strong evidence suggesting that changes in water and nutrient availability have a direct impact on the life history and functioning of mountain organisms. Despite these important findings, there are several gaps that require urgent attention. These include experiments testing adult trees in tropical and boreal regions, assessing animal responses and biotic interactions, and investigating aquatic environments and soil systems more extensively. A broader approach that integrates experimental data with field observations and relies on international collaboration through coordinated experiments could help address these gaps and provide a more consistent and robust picture of the impacts of global change on mountain ecosystems. [ABSTRACT FROM AUTHOR]