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Soil hosts key components of terrestrial biodiversity providing essential services to the below- and above-ground ecosystems. The worldwide retreat of glaciers is exposing new deglaciated terrains, offering a unique opportunity to understand the development of soil ecosystems under a changing climate. Many studies have investigated how biotic communities change after deglaciation, but protists have often been overlooked despite their key role in multiple ecosystem functions. Here, we aim to understand how protist communities develop along glacier forelands, describing their successional trajectories. Protist communities were characterized in 1251 soil samples from 46 glacier forelands across four continents. We used environmental DNA metabarcoding to identify the Molecular Operational Taxonomic Units (MOTUs) of protists based on a universal eukaryotic marker. The detected MOTUs were combined with information on multiple traits to assess how the functional diversity and composition of protist communities vary through time. Immediately after glacier retreat, protist communities are like those of polar and high-altitude habitats, with consumers being the dominant trophic group, followed by a relevant presence of phototrophs, while parasites were underrepresented. Over the succession, we detected an increase in taxonomic and functional diversity, but some highly specialized groups (e.g. phototrophic algae) declined. The use of a trait-based approach allowed us to identify distinct successional patterns depending on functional groups. Through the functional characterization of a crucial but understudied component of soil biotic communities, our study added one of the final pieces needed to predict how soil ecosystems will develop in the rapidly changing environment of glacier forelands., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Glaciers host a variety of cold-adapted taxa, many of which have not yet been described. Interactions among glacier organisms are even less clear. Understanding ecological interactions is crucial to unravelling the functioning of glacier ecosystems, particularly in light of current glacier retreat. Through a review of the existing literature, we aim to provide a first overview of the biodiversity, primary production, trophic networks, and matter flow of a glacier ecosystem. We use the Forni Glacier (Central Italian Alps) - one of the best studied alpine glaciers in the world - as a model system for our literature review and integrate additional original data. We reveal the importance of allochthonous organic matter inputs, of Cyanobacteria and eukaryotic green algae in primary production, and the key role of springtails (Vertagopus glacialis) on the glacier surface in sustaining populations of two apex terrestrial predators: Nebria castanea (Coleoptera: Carabidae) and Pardosa saturatior (Araneae: Lycosidae). The cryophilic tardigrade Cryobiotus klebelsbergi is the apex consumer in cryoconite holes. This short food web highlights the fragility of nodes represented by invertebrates, contrasting with structured microbial communities in all glacier habitats. Although further research is necessary to quantify the ecological interactions of glacier organisms, this review summarises and integrates existing knowledge about the ecological processes on alpine glaciers and supports the importance of glacier-adapted organisms in providing ecosystem services., (© 2024 The Author(s). Biological Reviews published by John Wiley & Sons Ltd on behalf of Cambridge Philosophical Society.)

The global retreat of glaciers is dramatically altering mountain and high-latitude landscapes, with new ecosystems developing from apparently barren substrates 1-4 . The study of these emerging ecosystems is critical to understanding how climate change interacts with microhabitat and biotic communities and determines the future of ice-free terrains 1,5 . Here, using a comprehensive characterization of ecosystems (soil properties, microclimate, productivity and biodiversity by environmental DNA metabarcoding 6 ) across 46 proglacial landscapes worldwide, we found that all the environmental properties change with time since glaciers retreated, and that temperature modulates the accumulation of soil nutrients. The richness of bacteria, fungi, plants and animals increases with time since deglaciation, but their temporal patterns differ. Microorganisms colonized most rapidly in the first decades after glacier retreat, whereas most macroorganisms took longer. Increased habitat suitability, growing complexity of biotic interactions and temporal colonization all contribute to the increase in biodiversity over time. These processes also modify community composition for all the groups of organisms. Plant communities show positive links with all other biodiversity components and have a key role in ecosystem development. These unifying patterns provide new insights into the early dynamics of deglaciated terrains and highlight the need for integrated surveillance of their multiple environmental properties 5 ., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

The development of terrestrial ecosystems depends greatly on plant mutualists such as mycorrhizal fungi. The global retreat of glaciers exposes nutrient-poor substrates in extreme environments and provides a unique opportunity to study early successions of mycorrhizal fungi by assessing their dynamics and drivers. We combined environmental DNA metabarcoding and measurements of local conditions to assess the succession of mycorrhizal communities during soil development in 46 glacier forelands around the globe, testing whether dynamics and drivers differ between mycorrhizal types. Mycorrhizal fungi colonized deglaciated areas very quickly (< 10 yr), with arbuscular mycorrhizal fungi tending to become more diverse through time compared to ectomycorrhizal fungi. Both alpha- and beta-diversity of arbuscular mycorrhizal fungi were significantly related to time since glacier retreat and plant communities, while microclimate and primary productivity were more important for ectomycorrhizal fungi. The richness and composition of mycorrhizal communities were also significantly explained by soil chemistry, highlighting the importance of microhabitat for community dynamics. The acceleration of ice melt and the modifications of microclimate forecasted by climate change scenarios are expected to impact the diversity of mycorrhizal partners. These changes could alter the interactions underlying biotic colonization and belowground-aboveground linkages, with multifaceted impacts on soil development and associated ecological processes., (© 2024 The Authors. New Phytologist © 2024 New Phytologist Foundation.)

The mechanisms underlying plant succession remain highly debated. Due to the local scope of most studies, we lack a global quantification of the relative importance of species addition 'versus' replacement. We assessed the role of these processes in the variation (β-diversity) of plant communities colonizing the forelands of 46 retreating glaciers worldwide, using both environmental DNA and traditional surveys. Our findings indicate that addition and replacement concur in determining community changes in deglaciated sites, but their relative importance varied over time. Taxa addition dominated immediately after glacier retreat, as expected in harsh environments, while replacement became more important for late-successional communities. These changes were aligned with total β-diversity changes, which were more pronounced between early-successional communities than between late-successional communities (>50 yr since glacier retreat). Despite the complexity of community assembly during plant succession, the observed global pattern suggests a generalized shift from the dominance of facilitation and/or stochastic processes in early-successional communities to a predominance of competition later on., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

Traces from bodies can be of various nature, for example of biological or inorganic origin. Some of these historically have received more consideration than others in forensic practice. Samplings of gunshot residues or biological fluid traces are commonly standardized, whereas macroscopically invisible environmental traces are usually ignored. This paper simulated the interaction between a cadaver and a crime scene by placing skin samples on the ground of five different workplaces and inside the trunk of a car. Traces on samples were then investigated through different approaches: the naked eye, episcopic microscope, Scanning Electron Microscopy (SEM) with Energy-dispersive X-ray spectroscopy (EDX) and Energy Dispersive X-Ray Fluorescence (ED-XRF). The purpose is to provide the forensic scientist with the awareness of the value of debris on skin and then to highlight implications for forensic investigations. Results demonstrated that even naked eye observation can reveal useful trace materials, for defining the possible surrounding environment. As a next step, the episcopic microscope can increase the number of visible particulates and their analysis. In parallel, the ED-XRF spectroscopy can be useful to add a first chemical composition to the morphological data. Finally, the SEM-EDX analysis on small samples can provide the greatest morphological detail and the most complete chemical analysis, although limited, like the previous technique, to inorganic matrices. The analysis of debris on the skin, even with the difficulties due to the presence of contaminants, can provide information on the environments involved in criminal events that can add to the investigation framework., (© 2023. The Author(s).)

The worldwide retreat of glaciers is causing a faster than ever increase in ice-free areas that are leading to the emergence of new ecosystems. Understanding the dynamics of these environments is critical to predicting the consequences of climate change on mountains and at high latitudes. Climatic differences between regions of the world could modulate the emergence of biodiversity and functionality after glacier retreat, yet global tests of this hypothesis are lacking. Nematodes are the most abundant soil animals, with keystone roles in ecosystem functioning, but the lack of global-scale studies limits our understanding of how the taxonomic and functional diversity of nematodes changes during the colonization of proglacial landscapes. We used environmental DNA metabarcoding to characterize nematode communities of 48 glacier forelands from five continents. We assessed how different facets of biodiversity change with the age of deglaciated terrains and tested the hypothesis that colonization patterns are different across forelands with different climatic conditions. Nematodes colonized ice-free areas almost immediately. Both taxonomic and functional richness quickly increased over time, but the increase in nematode diversity was modulated by climate, so that colonization started earlier in forelands with mild summer temperatures. Colder forelands initially hosted poor communities, but the colonization rate then accelerated, eventually leveling biodiversity differences between climatic regimes in the long term. Immediately after glacier retreat, communities were dominated by colonizer taxa with short generation time and r-ecological strategy but community composition shifted through time, with increased frequency of more persister taxa with K-ecological strategy. These changes mostly occurred through the addition of new traits instead of their replacement during succession. The effects of local climate on nematode colonization led to heterogeneous but predictable patterns around the world that likely affect soil communities and overall ecosystem development., (© 2023 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Ice-free areas are expanding worldwide due to dramatic glacier shrinkage and are undergoing rapid colonization by multiple lifeforms, thus representing key environments to study ecosystem development. It has been proposed that the colonization dynamics of deglaciated terrains is different between surface and deep soils but that the heterogeneity between communities inhabiting surface and deep soils decreases through time. Nevertheless, tests of this hypothesis remain scarce, and it is unclear whether patterns are consistent among different taxonomic groups. Here, we used environmental DNA metabarcoding to test whether community diversity and composition of six groups (Eukaryota, Bacteria, Mycota, Collembola, Insecta, and Oligochaeta) differ between the surface (0-5 cm) and deeper (7.5-20 cm) soil at different stages of development and across five Alpine glaciers. Taxonomic diversity increased with time since glacier retreat and with soil evolution. The pattern was consistent across groups and soil depths. For Eukaryota and Mycota, alpha-diversity was highest at the surface. Time since glacier retreat explained more variation of community composition than depth. Beta-diversity between surface and deep layers decreased with time since glacier retreat, supporting the hypothesis that the first 20 cm of soil tends to homogenize through time. Several molecular operational taxonomic units of bacteria and fungi were significant indicators of specific depths and/or soil development stages, confirming the strong functional variation of microbial communities through time and depth. The complexity of community patterns highlights the importance of integrating information from multiple taxonomic groups to unravel community variation in response to ongoing global changes., (© 2022 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

The surveying of European Union (EU) Annex I habitat "8110 - Siliceous scree of the montane to snow levels (Androsacetalia alpinae and Galeopsietalia ladani)" is generally executed by humans. However, robots could increase human monitoring capabilities. To this end, we collected information on this habitat employing the quadrupedal robot ANYmal C. These data include videos of eight different typical or early warning species. Additionally, data on four relevés are provided. These consist, for instance, of the robot state, and videos and pictures collected to evaluate the habitat conservation status. The aim of this dataset is to help researchers in a variety of fields. For instance, information on plant species collected by the robot can be utilized to develop new procedures and new metrics to assess the habitat conservation status or to train neural networks for plant classification. On the other hand, engineers can use robot state information to validate their algorithms. This database is publicly available in the provided Zenodo repository., (© 2023. The Author(s).)

Landscapes nearby glaciers are disproportionally affected by climate change, but we lack detailed information on microclimate variations that can modulate the impacts of global warming on proglacial ecosystems and their biodiversity. Here, we use near-subsurface soil temperatures in 175 stations from polar, equatorial and alpine glacier forelands to generate high-resolution temperature reconstructions, assess spatial variability in microclimate change from 2001 to 2020, and estimate whether microclimate heterogeneity might buffer the severity of warming trends. Temporal changes in microclimate are tightly linked to broad-scale conditions, but the rate of local warming shows great spatial heterogeneity, with faster warming nearby glaciers and during the warm season, and an extension of the snow-free season. Still, most of the fine-scale spatial variability of microclimate is one-to-ten times larger than the temporal change experienced during the past 20 years, indicating the potential for microclimate to buffer climate change, possibly allowing organisms to withstand, at least temporarily, the effects of warming., (© 2023. Springer Nature Limited.)

Pollen tubes are tip-growing cells that create safe routes to convey sperm cells to the embryo sac for double fertilization. Recent studies have purified and biochemically characterized detergent-insoluble membranes from tobacco pollen tubes. These microdomains, called lipid rafts, are rich in sterols and sphingolipids and are involved in cell polarization in organisms evolutionarily distant, such as fungi and mammals. The presence of actin in tobacco pollen tube detergent-insoluble membranes and the preferential distribution of these domains on the apical plasma membrane encouraged us to formulate the intriguing hypothesis that sterols and sphingolipids could be a "trait d'union" between actin dynamics and polarized secretion at the tip. To unravel the role of sterols and sphingolipids in tobacco pollen tube growth, we used squalestatin and myriocin, inhibitors of sterol and sphingolipid biosynthesis, respectively, to determine whether lipid modifications affect actin fringe morphology and dynamics, leading to changes in clear zone organization and cell wall deposition, thus suggesting a role played by these lipids in successful fertilization.

In mountain ecosystems, climate change can cause spatiotemporal shifts, impacting the composition of communities and altering fundamental biotic interactions, such as those involving flower-visiting arthropods. On of the main problems in assessing the effects of climate change on arthropods in these environments is the lack of baseline data. In particular, the arthropod communities on early flowering high-altitude plants are poorly investigated, although the early season is a critical moment for possible mismatches. In this study, we characterised the flower-visiting arthropod community on the early flowering high-altitude Alpine plant, Androsace brevis (Primulaceae). In addition, we tested the effect of abiotic factors (temperature and wind speed) and other variables (time, i.e., hour of the day, and number of flowers per plant) on the occurrence, abundance, and diversity of this community. A. brevis is a vulnerable endemic species growing in the Central Alps above 2000 m asl and flowering for a very short period immediately after snowmelt, thus representing a possible focal plant for arthropods in this particular moment of the season. Diptera and Hymenoptera were the main flower visitors, and three major features of the community emerged: an evident predominance of anthomyiid flies among Diptera, a rare presence of bees, and a relevant share of parasitoid wasps. Temperature and time (hour of the day), but not wind speed and number of flowers per plant, affected the flower visitors' activity. Our study contributes to (1) defining the composition of high-altitude Alpine flower-visiting arthropod communities in the early season, (2) establishing how these communities are affected by environmental variables, and (3) setting the stage for future evaluation of climate change effects on flower-visiting arthropods in high-altitude environments in the early season.

Hair can retain important biological traces for forensic investigations. Forensic scientists are used to looking for such traces on clothing and skin of victims, however, when decomposition kicks in and all that remains of the victims is the skeleton, hair may be the only tissue representing the surface of the body at the time of a crime on which biological traces of an aggressor may have been left and still be detectable. Given the lack of research on this topic, this pilot study aims to assess the capacity of hair to retain semen and blood in hair, and the possibility to detect these fluids with well-known techniques and to obtain a useful genetic profile even when exposed to environmental conditions (Open Natural Environment (woods), Open Man Made Environment (urban)) for three months. Results showed that both traces were always visible and detectable with almost all techniques in the Control Environment, while in the two open environments some difficulties arose. However, biomolecular analysis was effective up to three months on both fluids in the Natural Environment and up to two months and one week respectively on blood and semen in the Man Made Environment. The Combur Test, OBTI, and Luminol were effective on blood up to three months in both environments while Sperm-HY-Liter and observation of cellular components were effective on semen up to at least 1 month and PSA testing was positive up to 1 week in both environments. The present work can be considered an encouraging starting point for the analysis of biological traces on hair in forensic contexts, regardless of the PMI, since blood and semen related to a crime may survive., (Copyright © 2021 The Chartered Society of Forensic Sciences. Published by Elsevier B.V. All rights reserved.)

When dealing with complex crimes such as rape and assault, every trace takes on an essential role. The hands are often the only means of defence and offence for the victim as well as a frequent area of contact with the environment; fingernails of a victim are a well-known possible source of DNA of the aggressor; nevertheless, they are more rarely treated as an area of interest for non-genetic material, particularly on living victims. The hyponychium, because of its physiological protective function, lends itself ideally to retaining different kinds of traces representative of an environment or various products and substrates that could shed light on the environment and objects involved in the event. We therefore tested how far this capability of the hyponychium could go by simulating the dynamics of contamination of the nail through scratching on different substrates (brick and mortar, painted wood, ivy leaves, cotton and woollen fabric, soil) and persistence of any contaminant at different time intervals. We have thus shown how these traces may remain in the living for up to 24 h after the event using inexpensive and non-destructive techniques such as the episcopic and optical microscope., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

It is commonly accepted that crime scene recovery and recording are key moments of any judicial inspection in which investigators must decide on the correct strategies to put into place. Complex outdoor scenarios, presenting partially or entirely skeletonised remains, can benefit more than others by the intervention of environmental specialists (forensic anthropologists, archaeologists, entomologists and botanists). These experts are capable of singling out, correctly recording and recovering environmental evidence that can lead to a more comprehensive reconstruction of a given criminal episode. If human remains are discovered in an outdoor scenario, the on-site presence of a botanist will guarantee a correct approach to the identification, recording and recovery of any botanical evidence. If an on-site botanist is not available, the operators must be capable of both the botanical evaluation of a scene and the implementation of correct botanical sampling protocols.The following collection of unusual case histories that aim at underlining the efficacy of forensic botany will examine the determination of post mortem or the post depositional interval, evidence for a victim's post mortem transfer, evidence for the identification of a primary crime scene and evidence for the identification of a victim's dismemberment site. In another two cases, one, we will illustrate the important role that forensic botany played in the discrimination between botanical material used to voluntarily conceal a victim and vegetation that had grown naturally above a disposal site, whereas the other will highlight the protocols implemented for the identification of a murder weapon.

Aldrovanda vesiculosa (Droseraceae) is a rare aquatic carnivorous plant, distributed in Europe, Asia, Africa, and Australia. Aldrovanda populations can flower prolifically under favourable conditions, but seed set is very limited. We studied the structure of Aldrovanda pollen collected from flowers in different developmental stages (opened and non-opened anthers) from both European and Australian populations to elucidate pollination traits and the basis of poor seed set on the basis of microscopic observation of pollen and anther structure. Microscopic analyses of Aldrovanda pollen showed that this plant has pollen arranged in tetrads like other species in the Droseraceae family. In hydrated pollen, cytoplasmic protrusions originate from pores located along the equatorial wall of monads, and can develop into pollen tubes. Interestingly, pollen development from microspores occurs in open anthers, suggesting a delay of the developmental stages. In addition, pollen development displays altered sperm cell formation and precocious pollen germination. Precocious germination may characterize recalcitrant pollen, which naturally do not undergo dehydration before anthesis and remain partially hydrated, particularly in aquatic and wetland plants. These alterations of male gametophyte development could affect fertilization processes, and be the reason for the low reproductive capability of Aldrovanda observed both in the field and in cultures. Generally, reduced pollen longevity and very quick germination are considered an adaptation to aquatic or wet environments.

Plant science has been more and more utilized in forensic investigation, although its full potential is still to be reached. Plant macroremains are a powerful tool to link a body or other evidence back to a primary crime scene as they can provide detailed information about its previous ecological and geographic location. However, plant macroremains are often poorly preserved and difficult to identify, as diagnostic elements are seldom present within the assemblage occurring on the scene. Plant fragments most likely to be found are those exposed to the environment and resistant to degradation. The bark of woody plants meets these requirements but the possibility of its identification at species level from small fragments is not known. Starting from a real homicide case, where bark splinters were found on the victim, we aimed to assess the forensic potential of bark identification from small fragments like those likely to occur on a crime scene. Two identification keys were prepared for 16 common lowland tree species from Northern Italy; one key used all the available anatomical traits, the second only those from the outer bark. The second key was not able to discriminate some couples of species unambiguously, but could identify the bark fragments of the homicide as Robinia pseudoacacia, as confirmed from direct comparison with a reference sample. Bark fragments deserve to be included into the macroremains to be analyzed during an investigation, but small samples could easily lack diagnostic traits, and the building of a reference collection should be encouraged., Competing Interests: Declaration of Competing Interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Despite the rising interest in biotic interactions in mountain ecosystems, little is known about high-altitude flower-visiting arthropods. In particular, since the research in these environment can be limited or undermined by harsh conditions and logistical difficulties, it is mandatory to develop effective approaches that maximize possibilities to gather high-quality data. Here we compared two different methods, manual sampling and video observations, to investigate the interactions between the high-mountain arthropod community and flowers of Androsace brevis (Primulaceae), a vulnerable endemic alpine species with a short flowering period occurring in early season. We manually sampled flower-visiting arthropods according to the timed-observations method and recorded their activity on video. We assessed differences and effectiveness of the two approaches to estimate flower-visiting arthropod diversity and to identify potential taxa involved in A. brevis pollination. Both methods proved to be effective and comparable in describing the diversity of flower visitors at a high taxonomic level. However, with manual sampling we were able to obtain a fine taxonomic resolution for sampled arthropods and to evaluate which taxa actually carry A. brevis pollen, while video observations were less invasive and allowed us to assess arthropod behavior and to spot rare taxa. By combining the data obtained with these two approaches we could accurately identify flower-visiting arthropods, characterize their behavior, and hypothesize a role of Hymenoptera Apoidea and Diptera Brachycera in A. brevis pollination. Therefore, we propose integrating the two approaches as a powerful instrument to unravel interactions between flowering plants and associated fauna that can provide crucial information for the conservation of vulnerable environments such as high-mountain ecosystems.

Invasive alien plants are a major threat to biodiversity and they contribute to the unfavourable conservation status of habitats of interest to the European Community. In order to favour implementation of European Union Regulation no. 1143/2014 on invasive alien species, the Italian Society of Vegetation Science carried out a large survey led by a task force of 49 contributors with expertise in vegetation across all the Italian administrative regions. The survey summed up the knowledge on impact mechanisms of invasive alien plants in Italy and their outcomes on plant communities and the EU habitats of Community Interest, in accordance with Directive no. 92/43/EEC. The survey covered 241 alien plant species reported as having deleterious ecological impacts. The data collected illustrate the current state of the art, highlight the main gaps in knowledge, and suggest topics to be further investigated. In particular, the survey underlined competition as being the main mechanism of ecological impact on plant communities and Natura 2000 habitats. Of the 241 species, only Ailanthus altissima was found to exert an ecological impact on plant communities and Natura 2000 habitats in all Italian regions; while a further 20 species impact up to ten out of the 20 Italian administrative regions. Our data indicate that 84 out of 132 Natura 2000 Habitats (64%) are subjected to some degree of impact by invasive alien plants. Freshwater habitats and natural and semi-natural grassland formations were impacted by the highest number of alien species, followed by coastal sand dunes and inland dunes, and forests. Although not exhaustive, this research is the first example of nationwide evaluation of the ecological impacts of invasive alien plants on plant communities and Natura 2000 Habitats., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

As glaciers retreat, their forelands represent "natural laboratories" for the study of primary succession. This review describes how certain arthropods conquer pristine ground and develop food webs before the establishment of vascular plants. Based on soil samples, pitfall traps, fallout and sticky traps, gut content studies, and some unpublished data, we compare early arthropod succession on glacial forelands of northern Europe (Iceland, Norway including Svalbard, and Sweden) and of the Alps (Austria, Italy). While macroarthropod predators like ground beetles (Coleoptera: Carabidae), harvestmen (Arachnida: Opiliones), and spiders (Arachnida: Araneae) have usually been considered as pioneers, assumed to feed on airborne prey, this review explains a different pattern. Here, we highlight that springtails (Collembola), probably feeding on biofilm made up of algae or cyanobacteria, are super-pioneers, even at high altitudes and under arctic conditions. We also point out that macroarthropod predators can use locally available prey, such as springtails or non-biting midges (Diptera: Chironomidae). Pioneer arthropod communities vary under different biogeographical and climatic conditions. Two pioneer food webs, from northern Europe and the Alps, respectively, differed in structure and function. However, certain genera and orders were common to both. Generalists and specialists live together in a pioneer community. Cold-adapted specialists are threatened by glacier melting., Competing Interests: The authors declare no conflict of interest.

Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives., (© 2019 The Authors. Global Change Biology published by John Wiley & Sons Ltd.)

Fine regulation of exocytosis and endocytosis plays a basic role in pollen tube growth. Excess plasma membrane secreted during pollen tube elongation is known to be retrieved by endocytosis and partially reused in secretory pathways through the Golgi apparatus. Dissection of endocytosis has enabled distinct degradation pathways to be identified in tobacco pollen tubes and has shown that microtubules influence the transport of plasma membrane internalized in the tip region to vacuoles. Here, we used different drugs affecting the polymerization state of microtubules together with SYP21, a marker of prevacuolar compartments, to characterize trafficking of prevacuolar compartments in Nicotiana tabacum pollen tubes. Ultrastructural and biochemical analysis showed that microtubules bind SYP21-positive microsomes. Transient transformation of pollen tubes with LAT52-YFP-SYP21 revealed that microtubules play a key role in the delivery of prevacuolar compartments to tubular vacuoles., (© 2018 The Authors.)

Asexual taxa often have larger ranges than their sexual progenitors, particularly in areas affected by Pleistocene glaciations. The reasons given for this 'geographical parthenogenesis' are contentious, with expansion of the ecological niche or colonisation advantages of uniparental reproduction assumed most important in case of plants. Here, we parameterized a spread model for the alpine buttercup Ranunculus kuepferi and reconstructed the joint Holocene range expansion of its sexual and apomictic cytotype across the European Alps under different simulation settings. We found that, rather than niche broadening or a higher migration rate, a shift of the apomict's niche towards colder conditions per se was crucial as it facilitated overcoming of topographical barriers, a factor likely relevant for many alpine apomicts. More generally, our simulations suggest potentially strong interacting effects of niche differentiation and reproductive modes on range formation of related sexual and asexual taxa arising from their differential sensitivity to minority cytotype disadvantage., (© 2018 The Authors. Ecology Letters published by CNRS and John Wiley & Sons Ltd.)

The increasing use of phylogenetic methods in community ecology recognizes that accumulated evolutionary differences among species mirror, to some extent, ecological processes. The scope of this work is thus to propose a new method for the measurement of community-level phylogenetic redundancy, which takes into account the branching pattern of the underlying phylogeny. Like for functional redundancy, a measure of phylogenetic redundancy can be described as a normalized measure in the range (0-1) that relates the observed community-level phylogenetic diversity to the value of a hypothetical assemblage with the same abundance distribution of the focal community in which all species had independent evolution. Therefore, phylogenetic redundancy can be interpreted as the diversity decrease that is obtained by taking into account the evolutionary relationships among species in the calculation of diversity. The behavior of the proposed method, for which we provide a simple R function called 'phyloredundancy', was evaluated with published data on Alpine plant communities along a primary succession on a glacier foreland in northern Italy. As shown by our results, the method accounts for the length of shared branches in the phylogeny, producing a coherent framework for describing the evolutionary relationships within a species assemblage. Being based on classical diversity measures, which have been used in ecology for decades, it also has a great potential for future research in phylogenetic community ecology.

Tobacco seeds show a coat-imposed dormancy in which the seed envelope tissues (testa and endosperm) impose a physical constraint on the radicle protrusion. The germination-limiting process is represented by the endosperm rupture which is induced by cell-wall weakening. Transgenic tobacco seeds, obtained by insertion of exogenous genes codifying for seed-based oral vaccines (F18 and VT2eB), showed retarded germination with respect to the wild type and modified the expression of endogenous proteins. Morphological and proteomic analyses of wild type and transgenic seeds revealed new insights into factors influencing seed germination. Our data showed that the interference of exogenous DNA influences the germination rather than the dormancy release, by modifying the maturation process. Dry seeds of F18 and VT2eB transgenic lines accumulated a higher amount of reserve and stress-related proteins with respect to the wild type. Moreover, the storage proteins accumulated in tobacco F18 and VT2eB dry seeds have structural properties that do not enable the early limited proteolysis observed in the wild type. Morphological observations by electron and light microscopy revealed a retarded mobilization of the storage material from protein and lipid bodies in transgenic seeds, thus impairing water imbibition and embryo elongation. In addition, both F18 and VT2eB dry seeds are more rounded than the wild type. Both the morphological and biochemical characteristics of transgenic seeds mimic the seed persistent profile, in which their roundness enables them to be buried in the soil, while the higher content of storage material enables the hypocotyl to elongate more and the cotyledons to emerge.

Tree mortality is a key factor influencing forest functions and dynamics, but our understanding of the mechanisms leading to mortality and the associated changes in tree growth rates are still limited. We compiled a new pan-continental tree-ring width database from sites where both dead and living trees were sampled (2970 dead and 4224 living trees from 190 sites, including 36 species), and compared early and recent growth rates between trees that died and those that survived a given mortality event. We observed a decrease in radial growth before death in ca. 84% of the mortality events. The extent and duration of these reductions were highly variable (1-100 years in 96% of events) due to the complex interactions among study species and the source(s) of mortality. Strong and long-lasting declines were found for gymnosperms, shade- and drought-tolerant species, and trees that died from competition. Angiosperms and trees that died due to biotic attacks (especially bark-beetles) typically showed relatively small and short-term growth reductions. Our analysis did not highlight any universal trade-off between early growth and tree longevity within a species, although this result may also reflect high variability in sampling design among sites. The intersite and interspecific variability in growth patterns before mortality provides valuable information on the nature of the mortality process, which is consistent with our understanding of the physiological mechanisms leading to mortality. Abrupt changes in growth immediately before death can be associated with generalized hydraulic failure and/or bark-beetle attack, while long-term decrease in growth may be associated with a gradual decline in hydraulic performance coupled with depletion in carbon reserves. Our results imply that growth-based mortality algorithms may be a powerful tool for predicting gymnosperm mortality induced by chronic stress, but not necessarily so for angiosperms and in case of intense drought or bark-beetle outbreaks., (© 2016 John Wiley & Sons Ltd.)

Aim: Emerging polyploids may depend on environmental niche shifts for successful establishment. Using the alpine plant Ranunculus kuepferi as a model system, we explore the niche shift hypothesis at different spatial resolutions and in contrasting parts of the species range., Location: European Alps., Methods: We sampled 12 individuals from each of 102 populations of R. kuepferi across the Alps, determined their ploidy levels, derived coarse-grain (100 × 100 m) environmental descriptors for all sampling sites by downscaling WorldClim maps, and calculated fine-scale environmental descriptors (2 × 2 m) from indicator values of the vegetation accompanying the sampled individuals. Both coarse and fine-scale variables were further computed for 8239 vegetation plots from across the Alps. Subsequently, we compared niche optima and breadths of diploid and tetraploid cytotypes by combining principal components analysis and kernel smoothing procedures. Comparisons were done separately for coarse and fine-grain data sets and for sympatric, allopatric and the total set of populations., Results: All comparisons indicate that the niches of the two cytotypes differ in optima and/or breadths, but results vary in important details. The whole-range analysis suggests differentiation along the temperature gradient to be most important. However, sympatric comparisons indicate that this climatic shift was not a direct response to competition with diploid ancestors. Moreover, fine-grained analyses demonstrate niche contraction of tetraploids, especially in the sympatric range, that goes undetected with coarse-grained data., Main Conclusions: Although the niche optima of the two cytotypes differ, separation along ecological gradients was probably less decisive for polyploid establishment than a shift towards facultative apomixis, a particularly effective strategy to avoid minority cytotype exclusion. In addition, our results suggest that coarse-grained analyses overestimate niche breadths of widely distributed taxa. Niche comparison analyses should hence be conducted at environmental data resolutions appropriate for the organism and question under study.

The identification of red blood cells on both skeletal human remains and decomposed corpses is of remarkable importance in forensic sciences, irrespective of its diagnostic value; their presence is often perplexing and difficult to interpret especially when in the context of decomposition and taphonomical variables. Some clinical research has focused on the morphological changes of red blood cells over time by scanning electron microscopy (SEM), but no research has investigated whether botanical structures can be confused for red blood cells. Since some literature has recently presumed the detection of erythrocyte-like cells on skeletal remains (even ancient) as surely erythrocytes, and most have never taken into consideration the chance of an origin different from blood, such as botanical, the present study aims at verifying the possibility of confusion between erythrocytes and botanical cells by applying SEM analysis and at highlighting the pitfalls in this particular issue through a test submitted to pathologists and natural scientists asked to discriminate between red blood cells and different vegetal structures (60 images obtained by SEM analysis). The results showed that although there are diagnostic features useful in identifying red blood cells from botanical structures, some spores resulted very similar to decaying red blood cells, which calls for attention and great caution when studying decomposed human remains.

Polarized organization of the cytoplasm of growing pollen tubes is maintained by coordinated function of actin filaments (AFs) and microtubules (MTs). AFs convey post-Golgi secretory vesicles to the tip where some fuse with specific domains of the plasma membrane (PM). Secretory activity is balanced by PM retrieval that maintains cell membrane economy and regulates the polarized composition of the PM, by dividing lipids/proteins between the shank and the tip. Although AFs play a key role in PM internalization in the shank, the role of MTs in exo-endocytosis needs to be characterized. The present results show that integrity of the MT cytoskeleton is necessary to control exo-endocytosis events in the tip. MT polymerization plays a role in promoting PM invagination in the apex of tobacco pollen tubes since nocodazole affected PM internalization in the tip and subsequent migration of endocytic vesicles from the apex for degradation. MT depolymerization in the apex and shank was associated with misallocation of a significantly greater amount of internalized PM to the Golgi apparatus and its early recycling to the secretory pathway. Fluorescence Recovery After Photobleaching (FRAP) experiments also showed that MT depolymerization in the tip region influenced the rate of exocytosis in the central domain of the apical PM.

The estimation of the postmortem interval (PMI) is still one of the most challenging issues in forensic investigations, especially in cases in which advanced transformative phenomena have taken place. The dating of skeletal remains is even more difficult and sometimes only a rough determination of the PMI is possible. Recent studies suggest that plant analysis can provide a reliable estimation for skeletal remains dating, when traditional techniques are not applicable. Forensic Botany is a relatively recent discipline that includes many subdisciplines such as Palynology, Anatomy, Dendrochronology, Limnology, Systematic, Ecology, and Molecular Biology. In a recent study, Cardoso et al. (Int J Legal Med 2010;124:451) used botanical evidence for the first time to establish the PMI of human skeletal remains found in a forested area of northern Portugal from the growth rate of mosses and shrub roots. The present paper deals with a case in which the study of the growth rate of the bryophyte Leptodyctium riparium (Hedw.) Warnst, was used in estimating the PMI of some human skeletal remains that were found in a wooded area near Perugia, in Central Italy., (© 2012 American Academy of Forensic Sciences.)

Pollen tube growth depends on the integrity of the actin cytoskeleton that regulates cytoplasmic streaming and secretion. To clarify whether actin also plays a role in pollen tube endocytosis, Latrunculin B (LatB) was employed in internalisation experiments with tobacco pollen tubes, using the lipophilic dye FM4-64 and charged nanogold. Time-lapse analysis and dissection of endocytosis allowed us to identify internalisation pathways with different sensitivity to LatB. Co-localisation experiments and ultrastructural observations using positively charged nanogold revealed that LatB significantly inhibited endocytosis in the pollen tube shank, affecting internalisation of the plasma membrane (PM) recycled for secretion, as well as that conveyed to vacuoles. In contrast, endocytosis of negatively charged nanogold in the tip, which is also conveyed to vacuoles, was not influenced. Experiments of fluorescence recovery after photobleaching (FRAP) of the apical and subapical PM revealed domains with different rates of fluorescence recovery and showed that these differences depend on the actin cytoskeleton integrity. These results show the presence of distinct degradation pathways by demonstrating that actin-dependent and actin-indepedent endocytosis both operate in pollen tubes, internalising tracts of PM to be recycled and broken down. Intriguingly, although most studies concentrate on exocytosis and distension in the apex, the present paper shows that uncharacterised, actin-dependent secretory activity occurs in the shank of pollen tubes., (© 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.)

The burial of a body can affect plant communities through mechanical disturbance and nutrient balance alteration. We performed an experimental trial using five swine carcasses buried in an open site in Italy. Vegetation dynamics was monitored recording monthly every plant individual on a regular sampling grid during 1 year on the graves, on an empty control grave, and on an undisturbed plot. Plant species composition and cover were significantly different between the disturbed and the undisturbed plots. Disturbed plots showed the increase in ruderal species and the reduction in stress-tolerant ones. Graves and the control grave could not be distinguished from each other. Disturbance was the main factor affecting plant cover, while the presence of a buried body did not affect vegetation dynamics. However, disturbance could be easily detected; the functional approach seems promising for the identification of dynamic patterns to be used in different biogeographic and ecological contexts., (© 2012 American Academy of Forensic Sciences.)

The seasonal and spatial variability of polychlorinated biphenyls (PCBs) in vegetation and cow milk was studied in a high altitude pasture in the Alps (1900 m a.s.l.). PCB contamination in vegetation shows a concentration peak in June, which is mainly interpreted as the consequence of a temporary PCB enrichment of the air layer above the ground due to net emission fluxes from the soil. A three compartment dynamic model was developed to test this hypothesis. The North/South enrichment factor in the vegetation was 1.5-1.6 for penta- and hexa-substituted congeners and 1.7 for hepta- and octa-PCBs, according to the effect of temperature on compounds having higher K(oa) values. Milk concentrations followed the vegetation seasonal trend. The congener abundance in milk is in agreement with the biotransformation susceptibility, absorption efficiency and residence time of the different congeners in dairy cows., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

* The past and present occurrence of insect disturbance on white spruce (Picea glauca) trees was evaluated at their northern range limit on the eastern coast of Hudson Bay, and its effects on tree growth and population dynamics studied. * Three sites were sampled along an altitudinal gradient. Ring-width chronologies and stem analysis were used to evaluate tree growth. The occurrence of holes in the bark, of resin pockets and blue-stain fungi, and ring-width evidence for growth releases were used to assess the impact of bark beetle. * The white spruce population was established at these sites in the 17th century. Since their establishment, the spruce trees have developed a tree growth form, except at the uppermost site, where severe growth suppression occurred in the 19th century. Bark beetle and blue-stain fungi occurred with different timing and intensity. Their highest occurrence, associated with high mortality rates, was at the lowest site in the late 20th century. In the uppermost sites, biotic disturbance has occurred since the 18th century, associated with evidence for mechanical disturbance. * The simultaneous arrival of white spruce in the area resulted in a synchronous onset of spruce beetle activity driven by tree ageing. Unfavourable climatic conditions affected tree growth severely in the most exposed sites.

Positively charged nanogold was used as a probe to trace the internalization of plasma membrane (PM) domains carrying negatively charged residues at an ultrastructural level. The probe revealed distinct endocytic pathways within tobacco protoplasts and allowed the morphology of the organelles involved in endocytosis to be characterized in great detail. Putative early endosomes with a tubulo-vesicular structure, similar to that observed in animal cells, are described and a new compartment, characterized by interconnected vesicles, was identified as a late endosome using the Arabidopsis anti-syntaxin family Syp-21 antibody. Endocytosis dissection using Brefeldin A (BFA), pulse chase, temperature- and energy-dependent experiments combined with quantitative analysis of nanogold particles in different compartments, suggested that recycling to the PM predominated with respect to degradation. Further experiments using ikarugamycin (IKA), an inhibitor of clathrin-dependent endocytosis, and negatively charged nanogold confirmed that distinct endocytic pathways coexist in tobacco protoplasts.