33 research outputs found

    The Legacy of the Past Logging: How Forest Structure Affects Different Facets of Understory Plant Diversity in Abandoned Coppice Forests

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    Predicting how biodiversity affects ecosystem functioning requires a multifaceted approach based on the partitioning of diversity into its taxonomic and functional facets and thus redundancy. Here, we investigated how species richness (S), functional diversity (FD) and functional redundancy (FR) are affected by forest structure. Sixty-eight abandoned coppice-with-standards plots were selected in two mountain areas of the Apennine chain. We performed linear models to quantify the influence of structural parameters on S, FD and FR of clonal traits. Each diversity facet was affected differently by structural parameters, suggesting a complex interweaving of processes that influence the understory layer. Namely, tree layer density influences S, the height of the standards affects the lateral spread and persistence of clonal growth organs, and diameter of standards affects the FD of the number of clonal offspring. Opposite relationships compared to FD was found for the FR, suggesting how clonal traits play a key role in species assemblage. The observation that structural parameters exert opposite impact on FR seems to indicate a counterbalance effect on ecosystem stability. Multifaceted approaches yield a better understanding of relationship between forest structure and understory, and this knowledge can be exploited to formulate indications for more sustainable management practices

    Higher levels of protection do not consistently improve habitat quality: Insights from Mediterranean and Alpine shrublands

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    Protected areas are recognized as a crucial tool to mitigate ongoing trends of biodiversity loss. The effect of different levels of protection and their subsequent conservation efficiency remains, however, largely unexplored. To fill this gap, we present here an integrated approach that combines taxonomic analysis based on typical species to evaluate habitat quality and functional analysis based on plant traits to define habitat structure and functions. We focused on shrubland habitats across levels of protection in two different biogeographical areas. We found that habitat quality does not change linearly with levels of protection. Furthermore, the increase in habitat quality is characterized by a homogenization of habitat structure and functions, mostly driven by an increase in typical species. Our study suggests the level of protection afforded by protected areas is not necessarily indicative of their quality. A combined taxonomic and functional approach in protected areas can offer a thorough appraisal of habitat quality

    Prevalence, frequency, adverse events, and reasons for analgesic use in youth athletes:A systematic review and meta-analysis of 44,381 athletes

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    Objectives : To identify the prevalence, frequency, adverse effects, and reasons for analgesic use in youth athletes. Design : Systematic review and meta-analysis. Methods : Systematic searches in Embase, Medline, and SPORT-Discus from inception to September 2021, screening of reference lists, and citation tracking were performed to identify observational studies including athletes aged 15–24 years and reporting data on prevalence and/or frequency of analgesic use. Study quality was assessed using the Newcastle-Ottawa Scale. Random-effect proportion meta-analyses, stratified by type of analgesic medication and prevalence measure, estimated the prevalence of analgesic use. Data on usage frequency, adverse events, and reasons for analgesic use was synthesized narratively. Results : Forty-nine studies were included (44,381 athletes), of which 19 were good/high quality. Seven categories of analgesics were identified across 10 prevalence time-points. Meta-analyses suggested common use of NSAIDs (point prevalence 48 % [95 % CI 23 % to 73 %], in-season prevalence 92 % [95 % CI 88 % to 95 %]). The lowest prevalence was found for use of local anesthetic injections within the previous 12 months (2 % [95 % CI 1 % to 3 %]). Seven to 50 % of athletes reported weekly analgesics use. The proportion of adverse events ranged from 3.3 % to 19.2 %. Reasons for using analgesics included treatment of sports-related pain or injury, to treat illness, and to enhance performance. Conclusions : Analgesics are commonly used in youth athletes, but estimates vary depending on type of analgesic and prevalence measure. As the majority of studies were of poor methodological quality, future high-quality research should include prospective data collection of analgesic use to understand consumption trajectories

    Multiple drivers of functional diversity in temperate forest understories: Climate, soil, and forest structure effects

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    In macroecology, shifting from coarse- to local-scale explanatory factors is crucial for understanding how global change impacts functional diversity (FD). Plants possess diverse traits allowing them to differentially respond across a spectrum of environmental conditions. We aim to assess how macro- to microclimate, stand-scale measured soil properties, forest structure, and management type, influence forest understorey FD at the macroecological scale. Our study covers Italian forests, using thirteen predictors categorized into climate, soil, forest structure, and management. We analyzed five traits (i.e., specific leaf area, plant size, seed mass, belowground bud bank size, and clonal lateral spread) capturing independent functional dimensions to calculate the standardized effect size of functional diversity (SES-FD) for all traits (multi-trait) and for single traits. Multiple regression models were applied to assess the effect of predictors on SES-FD. We revealed that climate, soil, and forest structure significantly drive SES-FD of specific leaf area, plant size, seed mass, and bud bank. Forest management had a limited effect only. However, differences emerged between herbaceous and woody growth forms of the understorey layer, with herbaceous species mainly responding to climate and soil features, while woody species were mainly affected by forest structure. Future warmer and more seasonal climate could reduce the diversity of resource economics, plant size, and persistence strategies of the forest understorey. Soil eutrophication and acidification may impact the diversity of regeneration strategies; canopy closure affects the diversity of above- and belowground traits, with a larger effect on woody species. Multifunctional approaches are vital to disentangle the effect of global changes on functional diversity since independent functional specialization axes are modulated by different drivers

    Drivers of growth and establishment of the invasive plant Rumex acetosella within Andean fallow systems

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    Intensification of crop rotations and associated agricultural practices are reducing the capacity of traditional fallows to restore soil fertility and provide forage in Andean cropping systems. While the implementation of improved fallows offers great promise to enhance forage provision and maintain soil productivity, effects of these practices on the establishment of problematic weeds, including non-native plant species, remain poorly understood. To address this knowledge gap, we studied: i) how biotic and abiotic environmental factors influence the establishment and productivity of weeds in traditional fallows; and ii) to what extent improved fallows can help control weedy vegetation in smallholder rotations of the high Andes. Specifically, in this research, we focused on the invasive plant species Rumex acetosella L., which is a common concern of farmers throughout the central Peruvian Andes. We leveraged a multi-site, participatory research trial established in 2017 across eight communities in the region to understand the main drivers of R. acetosella presence and productivity. We used a total of 82 sites, each with paired treatments of traditional fallow (control with natural revegetation) and improved fallow (seeded with Vicia sativa L. and Avena sativa L.). Prior to treatment establishment we measured soil texture, pH, soil organic matter content as well as exchangeable macro-nutrients. Vegetation data was recorded in each treatment and divided into four categories: 1) A. sativa, 2) V. sativa, 3) R. acetosella, and 4) other weeds, and weighed to determine the relative biomass contribution of each. From these data, we calculated an index for R. acetosella pressure, weed pressure, and forage productivity. Our findings indicate that improved fallows greatly suppress weedy vegetation relative to unmanaged controls, including the invasive R. acetosella. Multivariate analyses suggested that R. acetosella abundance was associated with the presence of other non-planted weeds and predictors of soil fertility. The mean R. acetosella index in improved fallows was significantly lower compared to traditional fallows. We found R. acetosella biomass to be greater at lower productivity sites, i.e., those at higher elevations with cooler climates and sites with less fertile soils. Our findings indicate that if the fallow portion of a rotation is kept productive via adequate soil fertility inputs, the biomass of weeds, including the alien R. acetosella, is dramatically reduced

    Intraspecific variability of leaf form and function across habitat types

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    : Trait-based ecology has already revealed main independent axes of trait variation defining trait spaces that summarize plant adaptive strategies, but often ignoring intraspecific trait variability (ITV). By using empirical ITV-level data for two independent dimensions of leaf form and function and 167 species across five habitat types (coastal dunes, forests, grasslands, heathlands, wetlands) in the Italian peninsula, we found that ITV: (i) rotated the axes of trait variation that define the trait space; (ii) increased the variance explained by these axes and (iii) affected the functional structure of the target trait space. However, the magnitude of these effects was rather small and depended on the trait and habitat type. Our results reinforce the idea that ITV is context-dependent, calling for careful extrapolations of ITV patterns across traits and spatial scales. Importantly, our study provides a framework that can be used to start integrating ITV into trait space analyses

    Shedding light on typical species : implications for habitat monitoring

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    Habitat monitoring in Europe is regulated by Article 17 of the Habitats Directive, which suggests the use of typical species to assess habitat conservation status. Yet, the Directive uses the term “typical” species but does not provide a definition, either for its use in reporting or for its use in impact assessments. To address the issue, an online workshop was organized by the Italian Society for Vegetation Science (SISV) to shed light on the diversity of perspectives regarding the different concepts of typical species, and to discuss the possible implications for habitat monitoring. To this aim, we inquired 73 people with a very different degree of expertise in the field of vegetation science by means of a tailored survey composed of six questions. We analysed the data using Pearson's Chi-squared test to verify that the answers diverged from a random distribution and checked the effect of the degree of experience of the surveyees on the results. We found that most of the surveyees agreed on the use of the phytosociological method for habitat monitoring and of the diagnostic and characteristic species to evaluate the structural and functional conservation status of habitats. With this contribution, we shed light on the meaning of “typical” species in the context of habitat monitoring

    Plant–environment interactions through a functional traits perspective: a review of Italian studies

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    Italy is among the European countries with the greatest plant diversity due to both a great environmental heterogeneity and a long history of man–environment interactions. Trait-based approaches to ecological studies have developed greatly over recent decades worldwide, although several issues concerning the relationships between plant functional traits and the environment still lack sufficient empirical evaluation. To draw insights on the association between plant functional traits and direct and indirect human and natural pressures on the environmental drivers, this article summarizes the existing knowledge on this topic by reviewing the results of studies performed in Italy adopting a functional trait approach on vascular plants, bryophytes and lichens. Although we recorded trait measurements for 1418 taxa, our review highlighted some major gaps in plant traits knowledge: Mediterranean ecosystems are poorly represented; traits related to belowground organs are still overlooked; traits measurements for bryophytes and lichens are lacking. Finally, intraspecific variation has been little studied at community level so far. We conclude by highlighting the need for approaches evaluating trait–environment relationship at large spatial and temporal scales and the need of a more effective contribution to online databases to tie more firmly Italian researchers to international scientific networks on plant traits

    Thirty years of ecological research at the Gran Sasso d’Italia LTER site: climate change in action

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    Since 1986, vegetation monitoring of alpine plant communities has been performed at the Gran Sasso d’Italia LTER site (https://deims.org/c0738b00-854c-418f-8d4f-69b03486e9fd) in the Central Apennines, through phytosociological relevés and abundance and coverage estimation of the vascular flora at fine scale. The monitoring activities for abiotic parameters regard air and soil temperatures, rainfall, snowfall and snow cover persistence. A comparative analysis of changes in species composition, life forms, life strategies and morpho-functional types allowed recognition of dynamical processes (fluctuation and degeneration) and an increase in stress- and drought-tolerant and ruderal species, probably linked to a general process of climate change. A trend of variation forced by increasing drought was recorded in high-mountain plant communities, normally within a dynamic fluctuation process. There has been a 50–80% change in species composition with respect to the total number of species observed over the years. Whereas the total number of species has increased in all communities, in high-mountain mesic grassland 20% of sensitive species have completely disappeared. Early signs of a degeneration process were already discernible after seven years: such signs are more evident in snow-dependent communities, with a quantitative increase in more thermophilic and drought-tolerant species and a parallel decrease in more mesic, cryophilic and competitive species. In particular, the following phenomena have been recorded in high-mountain mesic grassland, in agreement with predicted or observed phenomena in other Alpine or Arctic areas: (a) coverage increase (or appearance) of ruderal and stress- and drought-tolerant species; (b) coverage decrease (or disappearance) of cryophilic, mesic and competitive species. These short-term changes could lead, in the medium- or long-term, to a disgregation process affecting the high elevation plant communities of the Apennines (including the local extinction of most of the cold-adapted species), due to their very low resilience. The phenomena described may be linked to the observed climate change which occurred during the last century (in particular in the last 50 years) in the Apennines, consisting mainly, in the mountains, of a strong reduction in the duration of snow-cover and an increase in mean and minimum annual temperatures

    Taxonomical, coenological and functional approach to analyse the effect of multi-year mowing on sub-Mediterranean invaded grasslands

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    The cessation of semi-extensive farming or underutilization of grasslands is leading to vegetation changes throughout Europe, as well as in semi-natural sub-Mediterranean mountains. At the community level, these changes foster the invasion of unpalatable tall grasses, mostly with competitive stress-tolerant strategies, affecting species diversity and decreasing the nutrient value of pastures ecosystem. In the Italian peninsula, two perennial species of Brachypodium are fostered by grazing cessation or by a livestock pressure below the theoretical carrying capacity of pasture: B. rupestre (Host) Roem. et Schult. in the sub-Mediterranean hills and low mountains, and B. genuense (DC.) Roem. et Schult. over 1300–1400 m a.s.l. These species can spread over a wide range of abiotic conditions, shifting their strategy thanks to their high intraspecific trait plasticity. Consequently, finding proper management practices to restore invaded grasslands is an important issue to preserve their biodiversity and economic value. This research was aimed to understand the effect of multi-annual mowing events on the recovery of a grassland community invaded by Brachypodium rupestre. In particular, we analysed the effects on taxonomic diversity, coenological composition, and trait composition (space occupation strategies, vegetative propagation, presence of storage organs, and flower- ing phenology) at the plant community level, and changes in B. rupestre traits. The study site was located next to the “Montagna di Torricchio” Natural Reserve (central Apennines) undergrazed since at least 30 years. We fenced one homogeneous area of 2 ha invaded by B. rupestre: half of the surface was mown twice a year since 2010, and hay and litter were removed after each mowing event; the other half was unmown and used as a control. Species cover (%) was recorded in 30 random plots (0.5 m × 0.5 m) in late June, before the start of the experiment and in the following six years. We collected also data on B. rupestre traits in mown and unmown areas (plant height, leaf area, leaf dry mass, seed mass, hypogeogenous rhizome dry matter content, and aboveground phytomass), and calculated Specific Leaf Area. B. rupestre cover and aboveground phytomass strongly decreased over time; species richness and transformed Shannon and Gini-Simpson indices increased, while Shannon’s evenness showed fluctuations. Fringe habitat and successional species, indicators of ongoing dynamic processes, decreased in cover, along with caespitose species, grasses, and species with rhizomes and runners as vegetative propagation modes. The cover of species that are typical of managed grasslands increased, as well as that of rosulate species, species with compact shoots with innovation buds at the axil of basal leaves, and species flowering in mid-late summer. The resulting species composition was consistent with that of central Apennines’ managed pastures. B. rupestre Specific Leaf Area did not show a significant trend, while both leaf area and leaf dry mass, as well as plant height and seed mass, decreased. These results suggest that B. rupestre reduces the amount of dry matter (e.g. structural and storage carbohydrates) inside the rhizomes and the investment in growth (horizontally and vertically) and in sexual reproduction. In summary, recurring mowing twice a year could represent the proper management practice to restore invaded grasslands, enhancing species diversity
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