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Natura 2000 is a European network of protected sites that should enable natural habitats to be maintained or restored at a favorable conservation status. Progress toward this objective must be periodically reported by states members of the European Union. We investigated how forest management plans might provide data to support the reporting. The study was done in the forests of the Dolomites and Venetian Prealps, Italy. Here, about 200 forest management plans, divided into several forest compartments, have been drawn up and revised every 10–15 years. Stand structure variables were retrieved from past (OR, 1970–1980) and more recent revisions (NR, 2000–2010) of 331 forest compartments ranging between 0.35 and 53.1 ha. In the beech and spruce forest habitat types (coded 9130 and 9410 in Annex I of the Directive 92/43/EEC, respectively), we found an increase from OR to NR in the density of large trees (from 32 to 46/ha and from 31 to 50/ha, respectively for the two habitats), basal area (from 27.3 to 31.5 m2/ha and from 31 to 34.5 m2/ha), mean diameter (from 34.1 to 36.2 cm and from 33.9 to 36 cm) and Gini index (from 0.35 to 0.37 and from 0.33 to 0.36). Pursuant to the Directive 92/43/EEC, the conservation status of these two habitat types should be taken as “favorable” with regards to the criterion related to the habitats’ specific structure and functions that are necessary for its long-term maintenance. We conclude that forest management plans provide a great portion of the information needed for assessing and monitoring the conservation status of forest habitat types in the Natura 2000 framework.

Human effects on the water economy of the river systems are currently well documented at the worldwide scale, impacting a range of ecosystem services. In this perspective article, we discuss the findings of recent papers that under different intensities of human disturbance have coupled the analyses of riverine geomorphological and plant community patterns. The discussion is carried out within the historical framework of past and current methods of sampling and analysing the river geomorphology and the plant communities along cross-sectional profiles. The research has been conducted along three major gravel-bed rivers of the south-eastern Italian Alps: Brenta, Piave, and Tagliamento. The collated and summarised results here demonstrate the existence of a strong relationship between the woody species variance that can be explained by geomorphologic patterns and human disturbance intensity. The less disturbed river has an intermediate value of species variance that can be explained by geomorphology, the intermediate-disturbed river has the highest value, and the highly disturbed river has the lowest value. Then, we proposed an interpretation key and an adaptation of the intermediate disturbance hypothesis, which reads as: “in rivers, the greatest influence of geomorphic properties on vegetation occurs in the moderate or middle ranges of a human disturbance gradient”. We argue that the “influence of the geomorphic properties on vegetation” is assessed through the species constrained variance through an ordination analysis, such as that which is explained here. The most recent collection techniques based on field survey and remote sensing are making it increasingly easy and accurate to study of the trends of geomorphic and plant community variables throughout time and space. Thus, we encourage that researchers should check whether and how our observation is conserved through different groups of taxa and intensities of natural and human disturbance.

Summary The Natura 2000 network, the pillar of biodiversity conservation in Europe, still shows some knowledge gaps after almost 30 years since its implementation. As birds are a taxonomic group that is underrepresented in the literature related to Natura 2000 compared to their importance in the EU Directives, this review investigated the characteristics of the scientific research dedicated to birds in relation to Natura 2000. This review focused on 169 peer-reviewed articles covering a period of 25 years (1995–2019). Most studies were set within single Natura 2000 site or regions within countries, and concerned terrestrial habitats, particularly wetlands. The terrestrial Mediterranean biogeographical region and marine Atlantic region had the greatest number of publications, while Spain, Italy, and France were the countries with the highest number of reviewed articles. The number of publications was correlated to Natura 2000 coverage at both country and biogeographical region level. Bird species were studied mainly at a community or single-species level and most publications studied distribution and occurrence of the bird species of interest, while very few assessed the conservation status of the species. Only a few articles set within Natura 2000 sites addressed the issues of habitat suitability for birds or the effectiveness of conservation efforts. Both Annex I and non-Annex I bird species were examined in the literature, with most species having decreasing population trends at the European scale. Future research on bird conservation and Natura 2000 should focus on marine ecosystems as well as habitats that have received less attention despite their important role in a changing future (alpine and urban types). Moreover, future studies should encompass larger spatial scales and those species for which status and trends are still not thoroughly investigated. Finally, it would be important to enhance research efforts on the conservation status and effectiveness in relation to the network.

According to the European Landscape Convention (ELC), a landscape means “an area, as perceived by people, whose character is the result of the action and interaction of natural and/or human factors”. Therefore, both human actions and natural processes play a role in shaping the landscape, which is, by this definition, ever changing. “Protecting” the landscape therefore means understanding, accepting and preserving such agents of change that have created it. Conversely, protective measures should not be designed to “freeze time”, nor to restore natural or human-influenced landscape features that have long ceased to exist. These basic concepts, delineated 20 years ago in Florence, are met in some parts of Italy by a dubious interpretation. Landscape protection agencies (Soprintendenze Archeologia Belle Arti e Paesaggio) seem to be oriented towards stopping or limiting the traditional activities that have shaped the current Italian forest landscape, with the purpose of increasing the forest cover for “aesthetic” reasons. Such narrow view contradicts the aims of the ELC and of the related national rules and mechanisms of landscape conservation.

Sustainably managed non-native trees deliver economic and societal benefits with limited risk of spread to adjoining areas. However, some plantations have launched invasions that cause substantial damage to biodiversity and ecosystem services, while others pose substantial threats of causing such impacts. The challenge is to maximise the benefits of non-native trees, while minimising negative impacts and preserving future benefits and options. A workshop was held in 2019 to develop global guidelines for the sustainable use of non-native trees, using the Council of Europe – Bern Convention Code of Conduct on Invasive Alien Trees as a starting point. The global guidelines consist of eight recommendations: 1) Use native trees, or non-invasive non-native trees, in preference to invasive non-native trees; 2) Be aware of and comply with international, national, and regional regulations concerning non-native trees; 3) Be aware of the risk of invasion and consider global change trends; 4) Design and adopt tailored practices for plantation site selection and silvicultural management; 5) Promote and implement early detection and rapid response programmes; 6) Design and adopt tailored practices for invasive non-native tree control, habitat restoration, and for dealing with highly modified ecosystems; 7) Engage with stakeholders on the risks posed by invasive non-native trees, the impacts caused, and the options for management; and 8) Develop and support global networks, collaborative research, and information sharing on native and non-native trees. The global guidelines are a first step towards building global consensus on the precautions that should be taken when introducing and planting non-native trees. They are voluntary and are intended to complement statutory requirements under international and national legislation. The application of the global guidelines and the achievement of their goals will help to conserve forest biodiversity, ensure sustainable forestry, and contribute to the achievement of several Sustainable Development Goals of the United Nations linked with forest biodiversity.

One of the implementing decrees of the Italian national forest law no. 34 of 2018 deals with the interventions to be set in the woodlands protected by the art. 136 of the national landscape and cultural heritage code (legislative decree no. 42 of 2004) and considered in compliance with the provisions of the landscape protection measures. The present commentary provides a basis for analysing the impact that the implementing decree could have and make suggestions for writing the decree. The commentary reviews the meaning of the various types of landscape use constraints, giving concrete examples and analyzing them with a focus on forest management. It presents an example framework of the interventions that could be the subject of the decree. Finally, it provides a summary of the key points to be addressed for the preparation of the decree.

Aim: To propose a Finite Mixture Model (FMM) as an additional approach for classifying large datasets of georeferenced vegetation plots from complex vegetation systems. Study area: The Italian peninsula including the two main islands (Sicily and Sardinia), but excluding the Alps and the Po plain. Methods: We used a database of 5,593 georeferenced plots and 1,586 vascular species of forest vegetation, created in TURBOVEG by storing published and unpublished phytosociological plots collected over the last 30 years. The plots were classified according to species composition and environmental variables using a FMM. Classification results were compared with those obtained by TWINSPAN algorithm. Groups were characterized in terms of ecological parameters, dominant and diagnostic species using the fidelity coefficient. Interpretation of resulting forest vegetation types was supported by a predictive map, produced using discriminant functions on environmental predictors, and by a non‐metric multidimensional scaling ordination. Results: FMM clustering obtained 24 groups that were compared with those from TWINSPAN, and similarities were found only at a higher classification level corresponding to the main orders of the Italian broadleaf forest vegetation: Fagetalia sylvaticae, Carpinetalia betuli, Quercetalia pubescenti-petraeae and Quercetalia ilicis. At lower syntaxonomic level, these 24 groups were referred to alliances and sub-alliances. Conclusions: Despite a greater computational complexity, FMM appears to be an effective alternative to the traditional classification methods through the incorporation of modelling in the classificatory process. This allows classification of both the co-occurrence of species and environmental factors so that groups are identified not only on their species composition, as in the case of TWINSPAN, but also on their specific environmental niche. Taxonomic reference: Conti et al. (2005). Abbreviations: CLM = Community-level models; FMM = Finite Mixture Model; NMDS = non‐metric multidimensional scaling.

Capacity development is essential for the effective management of protected areas and for achieving successful biodiversity conservation. European Natura 2000 sites form an extensive network of protected areas and developing the capacity of staff at all levels is a priority that will positively influence the appropriate implementation of conservation actions. In this study we identify the main challenges and potential solutions to developing the skills, knowledge and tools required for effective Natura 2000 site management. Our findings are based on a case study of the European project LIFE e-Natura2000.edu, which focuses on capacity development in practical biodiversity conservation and management through integrated and blended learning experiences (i.e. a combination of face-to-face and virtual teaching). We illustrate the main elements for successfully building capacity within a variety of knowledge and experience backgrounds and operating levels related to the management of Natura 2000 sites. Multifaceted, blended learning approaches are key to tackling the various needs of Natura 2000 managers in terms of skills, knowledge and tools.

Many forest tree species have been moved outside their native range to provide goods and services elsewhere, but some of them have become invasive, causing negative impacts on biodiversity and human activities. The assessment and knowledge on the degree and scale to which forest ecosystems are invaded by non-native trees is of paramount importance for tailored policies and strategies aiming at forest conservation. By analyzing main databases and literature and applying a four-level scale of invasion (not currently invaded and with low invasibility; potentially invasible; moderately invaded; massively invaded), we assessed the current and potential occurrence of twenty-five invasive non-native trees across forest ecosystems in Italy. Vulnerability to invasion substantially differed across forest categories, with riparian forests being particularly vulnerable to invasion. Acacia dealbata, Juglans nigra, Populus × canadensis and Prunus laurocerasus invaded a relatively small number of forest categories but showed their potential to widen their impact on others. Furthermore, some non-native species showed a recent increase of their invasive status in Italy. This study identified the Italian forest categories and non-native tree species that deserve primary attention, and can support proper management and allocation of funding to protect forests from the spread of invasive tree species.

Forests host most terrestrial biodiversity and their sustainable management is crucial to halt biodiversity loss. Although scientific evidence indicates that sustainable forest management (SFM) should be assessed by monitoring multi-taxon biodiversity, most current SFM criteria and indicators account only for trees or consider indirect biodiversity proxies. Several projects performed multi-taxon sampling to investigate the effects of forest management on biodiversity, but the large variability of their sampling approaches hampers the identification of general trends, and limits broad-scale inference for designing SFM. Here we address the need of common sampling protocols for forest structure and multi-taxon biodiversity to be used at broad spatial scales. We established a network of researchers involved in 41 projects on forest multi-taxon biodiversity across 13 European countries. The network data structure comprised the assessment of at least three taxa, and the measurement of forest stand structure in the same plots or stands. We mapped the sampling approaches to multi-taxon biodiversity, standing trees and deadwood, and used this overview to provide operational answers to two simple, yet crucial, questions: what to sample? How to sample? The most commonly sampled taxonomic groups are vascular plants (83% of datasets), beetles (80%), lichens (66%), birds (66%), fungi (61%), bryophytes (49%). They cover different forest structures and habitats, with a limited focus on soil, litter and forest canopy. Notwithstanding the common goal of assessing forest management effects on biodiversity, sampling approaches differed widely within and among taxonomic groups. Differences derive from sampling units (plots size, use of stand vs. plot scale), and from the focus on different substrates or functional groups of organisms. Sampling methods for standing trees and lying deadwood were relatively homogeneous and focused on volume calculations, but with a great variability in sampling units and diameter thresholds. We developed a handbook of sampling methods (SI 3) aimed at the greatest possible comparability across taxonomic groups and studies as a basis for European-wide biodiversity monitoring programs, robust understanding of biodiversity response to forest structure and management, and the identification of direct indicators of SFM., This review was funded by the EU Framework Programme Horizon 2020 through the COST Association: COST Action CA18207: BOTTOMSUP- Biodiversity Of Temperate forest Taxa Orienting Management Sustainability by Unifying Perspectives.

The monitoring of environmental policies in Europe has taken place since the 1980s and still remains a challenge for decision- and policy-making. For forests, it is concretized through the publication of a State Of Europe’s Forests every five years, the last report just been released. However, the process lacks a clear analytical framework and appears limited to orient and truly assess sustainable management of European forests. We classified the 34 quantitative sustainable forest management indicators in the Driver-Pressure-State-Impact-Response (DPSIR) framework to analyse gaps in the process. In addition, we classified biodiversity-related indicators in the simpler Pressure-State-Response (PSR) framework. We showed that most of the sustainable forest management indicators assess the state of European forests, but almost half could be classified in another DPSIR category. For biodiversity, most indicators describe pressures, while direct taxonomic state indicators are very few. Our expert-based classification show that sustainable forest management indicators are unbalanced regarding the DPSIR framework. However, completing this framework with other indicators would help to have a better view and more relevant tools for decision-making. The results for biodiversity were comparable, but we showed that some indicators from other criteria than the one dedicated to biodiversity could also help understanding threats and actions concerning it. Such classification helps in the decision process, but is not sufficient to fully support policy initiative. In particular, the next step would be to better understand the links between DPSIR and PSR categories.

Forest stand structure can be described through stand structural parameters as well as using stand structural indices. However, to date, there is still much uncertainty regarding how stand structural indices and parameters are intercorrelated. The analysis of correlation can guide their selection in research applications and forest management, avoiding redundancies and loss of time during data collection. In this study, using a sample of forest stands belonging to three forest types of the southeastern Italian Alps, we explored the correlation among stand structural indices, and then we checked the relationships between stand structural indices and stand structural parameters. The results indicate that the stand structural indices vary among the sampled forest types. Moreover, the correlation among stand structural indices indicates that some of them are strongly intercorrelated and, thus, they can give redundant information. Strong correlations have been found between the Shannon index and the Mingling index, between the Gini index and the Diameter differentiation index, and between size dominance indices. Correlations between stand structural indices and stand structural parameters were weak, and, therefore, we cannot recommend the exclusive use of stand structural indices as alternative to the common stand structural parameters. Instead, the combined use of stand structural indices and parameters can be a robust solution for describing forest stand structure.

The Natura 2000 network of protected sites is the pillar of biodiversity conservation in Europe. Although the Natura 2000 network directly addresses birds, these have shown worrying declining trends. It is therefore crucial to assess the potential contribution of Natura 2000 conservation measures. In this paper, we use a replicable method to model bird trends in the period 2000–2015 and the effects of Natura 2000 protection, across land cover classes, on regional abundances and local species richness and diversity. We model bird trends in Veneto, a North-Eastern Italian Region with areas among the richest in bird species in Italy. Bird data were derived from the national breeding bird monitoring scheme. Breeding birds showed declining trends at the regional level, confirming national and continental trends, particularly on agricultural and natural areas. The land cover class, rather than Natura 2000, mostly influenced population trends; however, it was possible to observe slightly higher estimates of species richness and diversity in Natura 2000 sites. Despite the absolute higher estimates of richness and diversity over the investigated period, farmland and woodland bird species had steeper declining trends inside Natura 2000 than outside, matching the values of the areas outside the network at the end of the survey period. We conclude that the Natura 2000 network capacity to buffer biodiversity loss and act as a species-pool for non-protected areas is decreasing over time, mainly with regards to farmland and woodland birds. Natura 2000 implementation must be improved: conservation objectives and measures, management, and monitoring should be better integrated into existing plans and funding should be made more efficiently available for Natura 2000.

Understanding and explaining the use of green spaces and forests is challenging for sustainable urban planning. In recent years there has been increasing demand for novel approaches to investigate urban green infrastructure by capitalizing on large databases from existing citizen science tools. In this study, we analyzed iNaturalist data to perform an assessment of the intentional use of these urban spaces for their value and to understand the main drivers. We retrieved the total number of observations obtained across a set of 672 European cities and focused on reporting from mapped green areas and forests. We used two separate multivariate explanatory models to investigate which factors explained variations in the number of observations for green areas and forests. We found a relatively heterogeneous use of these two urban green spaces. Gross domestic product was important in explaining the number of visits. Availability and accessibility also had positive relationships with the use of green areas and forests in cities, respectively. This study paves the way for better integration of citizen science data in assessing cultural services provided by urban green infrastructure and therefore in supporting the evaluation of spatial planning policies for the sustainable development of urban areas.

There are few better study ecosystems than forests to reveal global insights into the patterns and processes associated with biological invasions. Forests range from single species stands to some of the most biodiverse terrestrial ecosystems and are managed for a wide variety of environmental, social and economic values in myriad ways with equally contrasting intensity of effort. There are no forests left on the planet that are untouched by global environmental change. The impacts of non-native species invasions and anthropogenic climate change act individually and synergistically to drive considerable change in the direct and indirect interactions between species in these ecosystems. If we are to improve our management of non-native species, as well as conserve forest habitats worldwide, there is merit in bringing together contrasting examples to improve our understanding. Here we provide an overview of non-native species invasions in forest ecosystems using broad to fine scale examples to illustrate key patterns and highlight priority areas for future research. Our aim is to represent complex human interactions with the invasion phenomenon through the use of emblematic species groups (plants, pathogens and insects) and forest ecosystems (temperate and tropical). Specific attention is also given to the active management of the tree component because such management could be either the major factor of disturbance favouring non-native species spread or, conversely, the only way to prevent further invasions, which could happen without proactive mitigation.

Thirty-two trace elements were examined in the tree rings of downy oak to evaluate the pollution levels close to a cement plant isolated in a rural context and an industrial area where multiple sources of air pollution are or were present. Tree cores were collected from trees growing 1 km from both the cement plant and the industrial area that are located 8 km from each other. The analysis of the trace elements was performed on annual tree rings from 1990 to 2016 using laser ablation inductively coupled plasma mass spectrometry. Trace elements Cs, Mg, Mn, S and Zn reflected the emission history of the cement plant. Their values have increased since early 2000s, when the cement plant started its activity. However, the lack of significant trends of pollutants in the tree rings from the industrial area and the possible effect of translocation and volatility of some elements left open questions. The very weak changes of the other trace elements in the period 1990-2016 suggest those elements do not mark any additional effect of the industrial activity on the background pollution. The results confirm that downy oak trees growing close to isolated industrial plants must be considered a pollution forest archive accessible through dendrochemistry. © 2021 Springer Nature Switzerland AG, Environmental Science and Pollution Research, 28 (38), ISSN:0944-1344, ISSN:1614-7499

The Bakonjo have long practiced an agroforestry system of cultivation on the Ugandan slopes of the Rwenzori Mountain range. All terrain above 1600–2200 m has been strictly protected for many years because it is part of a national park. As a trade-off, the landscapes outside the park have been largely deforested. In the meantime, tourist numbers have increased. In Ruboni, a village of 1200 people, the closest to the eastern gate of the park, we interviewed a random sample of 51 residents aged >14 to understand how they perceived the landscape, park and tourism. Cultivated features were not essential to describe the place of residence, in contrast to natural features and human engineered devices. Cultivated and natural elements were judged as beautiful. Even if the inhabitants did not like human engineered facilities, they welcomed their improvement. The origin of native and non-native plants was not consistently recognized. These results show that the inhabitants feel affection for the agroforestry pattern of the Rwenzori landscape. However, ecological, social and economic pressures are challenging land use sustainability. This would be better addressed by an integrated pattern of land governance than the current two models: strict protection inside the park and relaxed land use outside.

Gravel-bed rivers exhibit remarkable dynamics and distinctive morphological patterns which influence the biological processes, as well as the river ecosystem resilience to human impacts. Classifications of river ecosystems into groups with morphologically distinct patterns are therefore of paramount importance for a better understanding of their dynamics, their management and conservation. Investigations on fluvial morphology and the related dynamics in Chilean gravel-bed rivers are still scarce, and, so far, no efforts have been made to identify latitudinal patterns of their morphological characteristics that may serve as a basis for further classification purposes. In fact, the great variability in bio-geographic, climatic, geologic and geomorphologic settings of the country offer an almost unique opportunity to study how the morphological characteristics of gravel-bed rivers may vary within extremely heterogeneous environments. We performed a regional analysis of nineteen Chilean gravel-bed rivers, from semi-arid Mediterranean to rainy temperate conditions (latitude ranging from 32° S to 39° S). Planform characteristics within these reaches were identified through interpretation of satellite images. Topographic features of the river basins were derived from open source digital elevation models and water discharge values were obtained from available national databases. We addressed the following research questions: a) can these 19 rivers be grouped into clusters considering their distinct planform characteristics of the river channel and basin features, as related to latitudinal gradients?, b) do river morphological characteristics vary along the analyzed latitudinal gradient?, c) does the distribution of specific geomorphic units (i.e. islands) follow a longitudinal pattern?, and finally, d) are these units associated to specific hidrogeomorfic characteristics? We generated a clustering which reflects latitudinal and morphological gradients in Chilean gravel-bed rivers, with the northernmost and southernmost rivers grouped according to their distinctive hydro-morphological characteristics and geomorphic units. We also observed a general tendency of an increase in the proportion of fluvial islands relative to the active channel area from the 33° Latitude in southward direction.

Public urban green spaces are crucial for citizens’ wellbeing and are an important part of daily life in cities. To maximize their benefits to quality of life a thorough knowledge of citizens’ preferences and preference heterogeneity is crucial in the planning and design of urban green spaces. This study investigated visitors’ perception of typical green spaces, with a focus on vegetation structure and the presence of typical historic city walls, as well as preferences within the context of perceived stress and safety. We conducted this study in the historic city of Padua in north-eastern Italy. In 2017, face-to-face interviews of citizens were held and choice sets, based on modified images of different green space scenarios, were used to test users’ preferences connected to both stress relief and safety perception. The study highlighted that general, stress relief and safety perception related preferences of the respondents depend on different site characteristics. Respondents preferred a complex but not too wild scenario with sparse trees and aesthetically appealing features such as colourful flowers. Historic walls had a negative effect on general preferences. While general preferences were very similar to stress relief preferences, preferences within the context of safety differed for some attributes. It seems that the vegetation structure and the presence of features linked to human recreational uses are important factors in planning and designing urban green spaces. Management and planning should take into consideration what users demand from green spaces as this will influence their suitable design.

Protection from landslides is one of the most important regulating services provided by forest ecosystems. Tree roots provide an increase in tensile strength, compression and shear resistance, compared to that uniquely due to the soil properties. This additional effect is known as root reinforcement. The degree of soil reinforcement given by roots have been modeled using laboratory and field data. The great spatial and temporal variability of root distribution is one of the main sources of uncertainty for the development of accurate and reliable models to quantify root reinforcement. The relative importance of stand structure remains poorly known. Here, we analyze the relationships between observed stand structure from a sample of spruce, beech, chestnut and mixed stands of the Southeastern Alps, and a spatially explicit model of root reinforcement. Data were collected in 20-m radius sampling units inclined 15-40° and covered by a low-resolution airborne LiDAR-derived canopy height model. Tree size and position were used to calculate root reinforcement through commonly used and calibrated models. Then, we studied the relationships between root reinforcement, stand structural indexes and area-based stand metrics from canopy height model. In specific conditions, the three groups of variables were correlated. Therefore, root reinforcement values might be spatially extrapolated through available canopy height models. Final step is to integrate the extrapolated values into a landslide susceptibility model, which combines other data available from forest plans, digital elevation models, geological and meteorological data. This study provides managers with a tool to periodically update maps of the service given by forest trees to protection of humans from landslides.

Myricaria germanica (German tamarisk or false tamarisk), Tamaricaceae, is a pioneer shrub species native to the Eurasian temperate zone where it colonises gravel bars in braided rivers. Over the past 150 years, human alterations of rivers have caused its dramatic decline in Europe. This paper reviews the current state of knowledge on the taxonomy, morphology, genetics, distribution, habitat, life cycle, uses, conservation and management of this riparian species.

The abandonment of silvicultural activities can lead to changes in species richness and composition of biological communities, when compared to those found in managed forests. The aim of this study was to compare the multi-taxonomical diversity of two mature silver fir-beech-spruce forests in the southern Dolomites (Italy), corresponding to the European Union habitat type 9130. The two sites share similar ecological and structural characteristics, but differ in their recent management histories. In the last 50 years, one site underwent non-intensive management, while the other was left unmanaged and was included in a forest reserve. The species richness and composition of eight taxa were surveyed in the two sites between 2009 and 2011. The difference in mean species richness between the two forest management types was tested through permutation tests, while differences in species composition were tested by principal coordinates analysis and the permutational multivariate analysis of variance. Mean species richness of soil macrofungi, deadwood lichens, bark beetles, and longhorn beetles were significantly higher in the abandoned than in the non-intensively managed forests. Deadwood fungi and epiphytic lichens did not differ in mean species richness between the two study sites, while mean species richness of ground beetles and birds were higher in the non-intensively managed than in the abandoned forest. Significant differences in species composition between the two sites were found for all the taxa, except for longhorn beetles. These results indicate that improving forest landscape heterogeneity through the creation of a mosaic of abandoned and extensively managed forests should better fulfill the requirements of ecologically different taxa.

Knowledge of the species composition of invaded vegetation helps to evaluate an ecological impact of aliens and design an optimal management strategy. We link a new vegetation analysis of a large dataset to the invasion history, ecology and management of Robinia pseudoacacia stands across Southern Europe and provide a map illustrating Robinia distribution. Finally, we compare detected relationships with Central Europe. We show that regional differences in Robinia invasion, distribution, habitats and management are driven both by local natural conditions (climate and soil properties, low competitive ability with native trees) and socioeconomic factors (traditional land-use). Based on the classification of 467 phytosociological releves we distinguished five broad vegetation types reflecting an oceanity-continentality gradient. The stands were heterogeneous and included 824 taxa, with only 5.8% occurring in more than 10% of samples, representing mainly hemerobic generalists of mesophilous, nutrient-rich and semi-shady habitats. The most common were dry ruderal stands invading human-made habitats. Among native communities, disturbed mesic and alluvial forests were often invaded throughout the area, while dry forests and scrub dominated in Balkan countries. Continuous, long-term and large-scale cultivation represent a crucial factor driving Robinia invasions in natural habitats. Its invasion should be mitigated by suitable management taking into account adjacent habitats and changing cultivation practices to select for native species. Robinia invasion has a comparable pattern in Central and Southern Europe, but there is a substantial difference in management and utilization causing heterogeneity of many South-European stands.

Green spaces and trees are fundamental for the sustainability of cities. The use of management and planning indicators for green spaces, including urban forests, have been proposed, but are rarely applied and their potential to provide ecological, social, and economic benefits is usually overlooked by policy makers and managers. Here, we apply a set of indicators describing green spaces and their variability in different urban units within the Basso Isonzo, an area of the city of Padua (northern Italy). Eleven indicators were selected based on their capacity to consider availability, accessibility and the preservation or increase of urban green spaces and tree cover. The value of indicators was standardized and enabled to have five classes indicating increasing performance. The study indicates green spaces’ heterogeneous conditions. Interestingly, the indicators commonly change moving from the city center to the outskirts. Monitoring through these indicators will enable understanding whether specific management and planning targets are met and, in the absence of these targets, identifying main trends over time. The proposed approach and indicators applied are simple to collect, analyze, and convey information. The indicators are related to relevant social, economic and ecological conditions pertaining to green spaces. The proposed indicators can therefore be used as a simple tool to guide decision-making with the aim of enhancing green spaces.

The potential effects of climate change on the distribution of Mediterranean plants at their peripheral range make them extremely vulnerable to environmental fluctuations. The northern-most Italian population of Cistus albidus provides an outstanding case for study, as it grows at the extreme northern edge of its range and because phenological data have been available since the early XIX century. In the period 2012–2017, we analysed the population demography and spatial structure, growth and flowering phenology, and genetic variability to understand the history, current state and possible evolution of this population. Lastly, the population data were tested for association with environmental factors. The population studied consists of plants on average 10 years old, showing the highest growth rates in spring and autumn. Anthesis starts in April and ends in early June and is significantly dependent on temperature. High levels of genetic variability are present (average He = 0.471), with heterozygote excess detected at four loci out of five. Bayesian analysis does not support any genetic structuring of the population. The aggregated pattern in the distribution of individuals and their phenological traits, together with the absence of genetic structuring, seem to suggest that this extreme geographical population is not currently endangered.

The call to set aside half of Earth's surface for nature conservation is gaining momentum across the conservation community. We propose that the experiences of Earth's most extensive conservation network, Natura 2000, offers important lessons on the challenges and opportunities of scaling up area-based conservation strategies. Natura 2000 has made unprecedented advances in implementing effective, evidence-based, internationally collaborative conservation policies and practices at continental scales. These advances have relied on strong governance frameworks, standardized policies, close integration of science and policy, flexibility in protection designations, a focus on conservation outside protected areas, economic interests and development, and the engagement and incentivization of stakeholders at different scales of reserve development and operation. Although failures and gaps remain, these hard-won lessons of Natura 2000 have much to offer those aiming to scale up conservation globally to meet the biodiversity challenges of the Anthropocene.

Policies to mitigate climate change and biodiversity loss often assume that protecting carbon-rich forests provides co-benefits in terms of biodiversity, due to the spatial congruence of carbon stocks and biodiversity at biogeographic scales. However, it remains unclear whether this holds at the scales relevant for management, with particularly large knowledge gaps for temperate forests and for taxa other than trees. We built a comprehensive dataset of Central European temperate forest structure and multi-taxonomic diversity (beetles, birds, bryophytes, fungi, lichens, and plants) across 352 plots. We used Boosted Regression Trees to assess the relationship between above-ground live carbon stocks and (a) taxon-specific richness, (b) a unified multidiversity index. We used Threshold Indicator Taxa ANalysis to explore individual species' responses to changing above-ground carbon stocks and to detect change-points in species composition along the carbon-stock gradient. Our results reveal an overall weak and highly variable relationship between richness and carbon stock at the stand scale, both for individual taxonomic groups and for multidiversity. Similarly, the proportion of win-win and trade-off species (i.e. species favored or disadvantaged by increasing carbon stock, respectively) varied substantially across taxa. Win-win species gradually replaced trade-off species with increasing carbon, without clear thresholds along the above-ground carbon gradient, suggesting that community-level surrogates (e.g. richness) might fail to detect critical changes in biodiversity. Collectively, our analyses highlight that leveraging co-benefits between carbon and biodiversity in temperate forest may require stand-scale management that prioritizes either biodiversity or carbon-in order to maximize co-benefits at broader scales. Importantly, this contrasts with tropical forests, where climate [...], Pre-review Version 2018, 07\23 + Supplementary information 43 Pages, 5 figures + 9 supplementary Figures

Urban forests have manifold social, economic, cultural and ecological benefits and are major components of the urban green infrastructure. Among them, spontaneous urban woodlands develop unintentionally on abandoned lands in both growing and shrinking cities and deserve additional attention. We aimed to describe the planning and social processes linked to failures and successes in recognising spontaneous woodlands in Italy. We collected data on the woodland area characteristics, urban settings, and former land use as well as on the planning and property evolution (e.g. land use zone designations) and citizens involvement for 19 sites in 13 representative Italian cities. Our results highlighted that spontaneous woodlands are heterogeneous in size and age, and grow on a variety of previous land uses, with residential and industrial being the most dominant. More than half of the urban plans designated land uses that require new soil sealing and tree plantations instead of maintaining the existing woodlands. Only in four case studies, urban plans recognised the spontaneous woodland, at least partially, as an element of the city’s green infrastructure. We pinpoint an overall deficiency of the planning process in considering spontaneous urban woodlands, although with some exceptions that can represent models for future planning. The role of citizens seemed pivotal, even if not necessarily decisive, in the promotion and maintenance of these woodlands as a real social and ecological asset. A complex and modern array of approaches should capitalise on the potential benefits of spontaneous urban woodlands with the participation of citizens as a strong element of governance.

Summary Field-margin diversification through conservation and restoration of hedgerows is becoming a prominent intervention for promoting biodiversity and associated ecosystem services in intensive agricultural landscapes. However, how increasing cover of hedgerows in the landscape can affect ecosystem services has rarely been considered. Here, we assessed the effect of increased field-margin complexity at the local scale and increasing cover of hedgerows in the landscape on the provision of pest control, weed control and potential pollination. Locally, three types of field margin were compared as follows: (i) standard grass margin, (ii) simple hedgerow and (iii) complex hedgerow, along two independent gradients of hedgerow cover and arable land cover in the landscape. We performed an exclusion experiment to measure biological control of cereal aphids and assessed natural enemy and pest abundance in the field. We sampled plant weed communities and performed a phytometer experiment to test the effects of pollinators on plant reproductive success. At the local scale, planting a new hedgerow or improving its structural complexity and vegetation diversity did not enhance the delivery of ecosystem services in the neighbouring field. However, high cover of hedgerows in the landscape enhanced aphid parasitism (from 12 to 18%) and potential pollination (visitation rate and seed set increased up to 70%) irrespective of local margin quality. The cover of arable land in the landscape reduced the abundance of plant-dwelling predators and weed diversity, but did not affect the delivery of the investigated ecosystem services. Synthesis and applications. Our results highlight the key importance of the surrounding landscape context, rather than local factors, to the delivery of ecosystem services. This suggests a need for new policies that pay particular attention to the conservation of hedgerows at large scales for promoting multiple ecosystem services in agroecosystems. Specifically, hedgerows can serve to develop a network of ecological corridors that can facilitate the movement of beneficial organisms, such as pollinators and natural enemies in the agricultural matrix. Such interventions may be a ‘low cost–high benefit solution’, since farmers can create or conserve high-quality habitats taking little or no land from crop production and without the need to change their crop management.

We compared three gravel-bed rivers in north-eastern Italy (Brenta, Piave, Tagliamento) having similar bioclimate, geology and fluvial morphology, but affected by different intensities of anthropogenic disturbance related particularly to hydropower dams, training works and instream gravel mining. Our aim was to test whether a corresponding difference in the interactions between vegetation and geomorphological patterns existed among the three rivers. In equally spaced and sized plots (n = 710) we collected descriptors of geomorphic conditions, and presence-absence of woody species. In the less disturbed river (Tagliamento), spatial succession of woody communities from the floodplain to the channel followed a profile where higher elevation floodplains featured more developed tree communities, and lower elevation islands and bars were covered by pioneer communities. In the intermediate-disturbed river (Piave), islands and floodplains lay at similar elevation and both showed species indicators of mature developed communities. In the most disturbed river (Brenta), all these patterns were simplified, all geomorphic units lay at similar elevations, were not well characterized by species composition, and presented similar persistence age. This indicates that in human-disturbed rivers, channel and vegetation adjustments are closely linked in the long term, and suggests that intermediate levels of anthropogenic disturbance, such as those encountered in the Piave River, could counteract the natural, more dynamic conditions that may periodically fragment vegetated landscapes in natural rivers. © 2015 Elsevier Ltd.

We propose a method for the appropriate assessment of adverse effects of roads in compliance with the European Union Habitats Directive. The method incorporates an analysis of ecological risk of edge effects by the proposed roads with the related increase in accessibility. The method was tested on 30 km of planned forest roads inside an 8,000-ha reserve included in two Natura 2000 sites. As a result, the cumulative effect of 19 road segments was judged as not significantly affecting the integrity of the sites, although they made accessible an extra 314 ha. On the basis of the accessibility calculation, 20 ha of land were set aside from forest exploitation as a mandatory mitigation measure. The method objectively determined the cumulative adverse effects, enabled comparison of plan revisions and alternatives and proved to measure direct and indirect significant effects with a realistic effort in terms of field survey and geographic information system processing.

Climate change is leading to the global loss of open montane meadows by facilitating tree and shrub encroachment at high elevations. North America’s coastal mountains are particularly vulnerable to these changes, as they are relatively low elevation compared with interior mountains and contain only small areas of alpine tundra. We compared aerial photographs from 1962 with those from 2005 covering three subalpine regions on Vancouver Island, British Columbia, to document the extent of changes in woody vegetation and investigate associations between vegetation change and topography. Mean proportional woody vegetation cover increased significantly from 0.75±0.03 to 0.81±0.03 between 1962 and 2005 (p < 0.0001). Relative increase in woody vegetation cover was greater at higher elevations and on northerly aspects. These findings confirm an upward expansion and infilling of trees and shrubs and a reduction of the area encompassed by open alpine tundra on Vancouver Island. Loss of open meadow conditions at high elevations in this region will likely have consequences for alpine plant and animal communities.

In densely populated areas, essential sources of ecosystem services are represented by green infrastructure, which includes trees outside forests (TOF) that, regardless of their cover extension, are found on agricultural or urban land. This research aims to assess landscape preference for TOF along an urban-rural-natural gradient in relation to different levels of landscape heterogeneity. Analyses are based on the integration of a visual choice experiment (360 respondents) with a GIS-based landscape analysis at regional scale in a Mediterranean region in Central Italy. Main findings revealed that correlation between landscape preference and heterogeneity varies along the urban&ndash, rural&ndash, natural gradient and on the basis of the spatial configuration of the surrounding landscape. The additional value of TOF to landscape preference is closely and positively linked to the degree of landscape anthropization. Conversely, TOF contribution to landscape preference resulted negative in natural landscapes where they can be perceived as a disturbance of the wilderness. Considering the influence that landscape preference plays on cultural ecosystem services provisioning and, in turn, on decision making processes, our results can support landscape policy and planning in fostering or hampering TOF diffusion depending on the different territorial contexts. These findings endorse the importance of multi-functional approaches in future-oriented strategies, which should mediate between the human preference for TOF, their ecological role and the provision of other services.

Plants are continuously exposed to human air pollution, absorbing pollutants in their tissues. Trees can store pollutants in wood, in the annual growth rings, retaining traces of pollutants in the environment. Information on past pollution events are archived by trees, which dendrochemistry, a dendrochronological science combined with chemistry, is able to access. Many authors have suggested that trees could complement the conventional environmental monitoring: a forest archive of pollution events. However, the implications of trees occurrence in polluted areas on planning and management have not yet been discussed. In this article, we investigate whether forest archives exist and whether they should be integrated into the network of existing monitoring stations. We use a case study, the Veneto region of Italy, one of the most polluted areas in Europe, to examine the occurrence of trees around 28 industrial plants retrieved from a European pollution register. We propose planning actions to develop the latent potential of these forest archives for environmental monitoring, which society may benefit. We follow three steps: (a) assessing the cover and composition of tree canopies around the industrial plants, (b) inventorying the existing artificial air monitoring stations in order to discover whether pollutants around the industrial plants are already monitored, (c) assessing land use patterns in order to identify which are the receptors of air pollution and enhance the forest archive in the future. These spatial analyses are conducted in a 1-km radius buffer with the industrial plant as the centre. Results show that forest archives are available, with cover and composition suitable for dendrochemistry studies. Artificial monitoring stations are too far from industrial plants or have been installed recently, unable to provide historical data. Trees are an alternative source of pollution data. Receptors of air pollution include a diversity of urban, rural and agricultural lands, where forest archives can be managed and conserved through a variety of actions. Environmental protection agencies should value these trees, preserving them and accessing the records held in this forest archive. Similar inventories must be promoted in other industrialised regions of the world even at larger scales. Studies like this one should also be incorporated into landscape or urban planning processes.

Land use by humans strongly alters the landscape mosaic, either by reducing or increasing its heterogeneity. One of the most recent and widespread land use changes in Europe has been the spontaneous reforestation of marginal agricultural lands. These primarily affected small landscape patches, such as trees outside forests (TOF) and small open areas (SOA), often represent the most diversifying features of landscape&rsquo, structures. Nevertheless, only small-scale studies can be found in the literature and thus it remains a relatively unexplored issue. Integrating inventory and cartographic approaches, this work assesses changes in abundance, coverage, and average size of small patches in Italy between 1990 and 2013. Main results showed an overall increase in number and coverage of small patches during the reference period. The average patch size remains unaltered for TOF but decreases significantly for SOA, due to trees encroachment and canopy cover increasing in forests. Our findings confirm the important changes in Mediterranean land mosaics and contribute to a better understanding of current conditions and recent trends regarding TOF and SOA. The integrated approach has proven to be helpful for the large-scale assessment of small patches dynamics, representing a viable monitoring tool to encourage the inclusion of small patches in landscape policy and planning.

The ongoing biodiversity crisis necessitates greater efforts to ensure the adequate conservation of critical habitat types. Even though the identification of protected areas is still required in Europe, conservation efforts are now focusing on management requirements for protected areas and habitat types. Establishing effective management approaches is important for the conservation of the natural and semi-natural habitat types that are identified under the Habitats Directive framework. In this study, we propose a methodology for determining priorities in the conservation management of habitat types based on readily available data. This method relies on four simple criteria to rank habitat types, which includes: conservation condition, biodiversity value, pressure factor, and the cover relevance of habitat types (indicating regional responsibility in terms of area covered). After ranking the habitat types based on the sum of the scores given to all of the criteria, the 25% top-ranking habitat types were prioritized. The pressure factors are analyzed using cluster analysis to better convey information regarding the management needs of groups of habitat types. This prioritization method was tested in habitat types occurring within the Italian Alpine and Continental biogeographical regions. From this analysis, forests, bogs and fens, and dry grasslands were identified as conservation priorities for the Alpine region; meanwhile, a wider variety of habitat types were identified for the Continental region. Important pressure factors were identified (e.g., roads and motorways) for these two biogeographical regions of Italy, which could be used to suggest specific conservation measures. The proposed approach represents a transparent and reliable method for outlining habitat-type priorities based on conservation, biodiversity, pressure, and cover factors, which can be applied to identifying conservation measures that can help achieve biodiversity targets.

The abandonment of agricultural use is a common driver of spontaneous reforestation by alien trees. The N-fixing black locust (Robinia pseudoacacia L.) is a major alien invader of old fields in Europe. Here we show that canopy dominance by this tree may filter the frequency distribution of plant functional traits in the understory of secondary woodlands. Higher soil C/N ratio and available P are associated with black locust stands, while higher soil phenols associate with native tree stands. These environmental effects result in differences in understory flowering periods, reproduction types and life forms. Our findings emphasize the effect of a major alien tree on functional plant trait composition in the early stages of spontaneous reforestation of abandoned lands, implying the development of a novel forest ecosystem on a large geographical scale.

Invasive alien tree species can strongly impact biodiversity and future projections predict their spread over natural, semi-natural and human habitats. However, little is known about plant communities that form during the first stages of invasion. We investigated the composition of plant communities in alien Robinia pseudoacacia L. secondary forests growing on grasslands and cultivated areas abandoned during the last 35-40 years in north-eastern Italy to understand whether these formations could cause floristic homogenization of plant communities composition. On the basis of a cluster analysis, plant communities were assigned to seven syntaxonomic categories and split into four groups characterized by the occurrence of 20 species indicative of (a) nitrogen-rich, (b) true forest and (c) open habitat conditions. RDA analysis enabled main stand and environmental variables filtering these communities to be identified and β-diversity components were partitioned through the SDR (Similarity - richness Difference - species Replacement) simplex approach. Plant composition patterns were significantly associated to variability in elevation, stand vertical structure, shrub cover, mean tree diameter and height, and basal area. Shrub cover discriminates between plant communities associated with open or shaded conditions. The partition of β-diversity components revealed that replacement is the prominent process structuring plant communities in these secondary forests. Our study showed that secondary Robinia forests growing on abandoned lands may host compositionally heterogeneous plant communities, thus contributing to regional biodiversity.

Improvements in the management of Natura 2000 sites are essential to achieve the targets set out by the Habitats and Birds Directives of the European Union. A current focus is on the development of management plans, which are fundamental instruments in the implementation of conservation measures. This study explores the viability of using existing forest plans to assist in this purpose. As case study, we consider the regulatory framework of the Veneto Region, northern Italy. We collected quantitative and qualitative data on forest plans at the regional and at three sub-regional spatial scales: local, district, and biogeographical. Forest plans cover about 54% of the terrestrial area of Natura 2000 sites in Veneto, and 75% of Sites of Community Importance in the Alpine biogeographical region. At the local scale of analysis, metrics from forest plans represent a valuable historical record which can be used to interpret the current state and future trends, especially for forests with long management records. These data can be used to assess biodiversity indicators for the monitoring of Natura 2000 forest and non-forest habitat types, in compliance with Article 17 of the Habitats Directive. Moreover, the heterogeneous stand conditions which are promoted by some forest management approaches can improve the conservation efforts for some habitat types and species. The scale of local forest plans are typically the most appropriate for implementing habitat management strategies. From this study, we conclude that management authorities should take advantage of the wide spatial coverage and distribution of existing forest plans, especially in mountain areas inside and outside the Natura 2000 network, for the successful conservation of European Union habitat types and species.

International audience; Aim: Biodiversity monitoring and conservation are extremely complex, and surrogate taxa may represent proxies to test methods and solutions. However, cross-taxon correlations in species diversity (i.e., cross-taxon congruence) may vary widely with spatial scale. Our goal is to assess how cross-taxon congruence varies with spatial scale in European temperate forests. We expect that congruence in species diversity increases when shifting from fine to coarse spatial scales, with differences between species richness and composition, and across pairs of taxonomic groups. Location: European temperate forests. Time period: Present. Major taxa studied: Vascular plants, bryophytes, birds, epiphytic lichens, saproxylic beetles and wood-inhabiting fungi. Methods: We used field data (354 plots across 23 sites) encompassing Italy, France and Hungary, with species information for six taxonomic groups. We accounted separately for spatial grain (the size of elementary sampling unit) and extent (the geographical area included in the survey) and evaluated the relationships within all the possible pairs of taxa. Results: Although no pair of taxa had its species richness consistently correlated across scales, we found no changes in the direction of correlations when analysing species composition. However, when increasing grain and extent, we did find a general increase in the magnitude of correlations in species composition and partial changes in significance, with plants having the highest number of significant correlations. Main conclusions: Species richness congruence among taxa is strongly scale dependent owing to differences in the relative contribution of large- and small-scale processes across taxa. Cross-taxon congruence in species composition is scale dependent only for its magnitude, because life-history traits of individual species make responses to environmental factors similar across scales. Forest monitoring should consider multi-taxon sampling and limit the use of surrogates at specific spatial scales, especially for species richness. Sampling plant species composition in scattered plots across different sites may effectively summarize the whole community composition.

Remnant riparian woodlands have an important landscape function, due to their ability to act as ecological corridors. In this study we used molecular markers to assess the genetic variation occurring within and between spontaneous white willow (Salix alba L.) riparian woodlands. Our main goal was to evaluate the extent to which the fragmentation of a woodland corridor along a heavily impacted river in northeastern Italy and stand structural conditions may have affected the population genetics. Although having different structures, the three examined white willow stands showed high estimates of genetic similarity, as well as low genetic differentiation between them, indicating that they shared a similar gene pool and that the stands could result from a common set of individual genotypes, and should be regarded as metapopulations. The magnitude of genetic diversity within each of the stands and genetic differentiation between them, despite their high sexual reproductive capacity associated with a highly marked gene flow, suggest that these stands are dynamic and capable of adaptive responses to possible changes in their fluvial environment. However, the factors influencing genetic diversity should be interpreted from a long-term perspective. Fluvial geomorphic patterns in regulated rivers may be modified to a degree that could lead to changes in dispersal processes, sexu­al reproduction vs. asexual propagation, and hence genetic diversity.

Invasive alien species are a threat to protected areas, species, and habitats worldwide. At the European level, the control of invasive alien species is a major goal of the EU Biodiversity Strategy, and a cornerstone, in this sense, is the Regulation (EU) no.1143/2014 on invasive alien species. In this study, we focus on the Alpine and Continental biogeographical regions of Europe (defined in art. 1 of the Habitats Directive; 92/43/EEC), and aim to give an overview of the main protected forest habitat types threatened by invasive alien species, and focus on five major invasive alien tree species (Acer negundo, Ailanthus altissima, Prunus serotina, Quercus rubra, and Robinia pseudoacacia). We considered the assessment reports under Article 17 of the Habitats Directive for the period 2007–2012, and six documents on the interpretation of habitats, to identify those most threatened by invasive alien species and in particular by the five invasive alien trees. We also assessed selected examples of impacts by these alien tree species on different species groups within Natura 2000 sites to highlight potential effects on biodiversity. Riparian forest habitats and oak dominated woodlands are among the most prone to invasion within the two biogeographical regions. A. altissima and R. pseudoacacia are the most reported invasive alien trees in these protected forest habitat types. Furthermore, examples of the impacts of these tree species have indicated potential detrimental effects on forest habitats structure and functions, and on single species listed in the Habitats and Birds Directives. In conclusion, we emphasise the need for effective management and systematic monitoring of these five invasive alien tree species within Natura 2000 sites.

Trees are natural repositories of valuable environmental information that is preserved in the growth and structure of their stems, branches and roots. Dendrochronological analyses, based on the counting, crossdating and characterisation of incrementally formed wood rings, offer powerful insights for diverse fields including ecology, climatology and archaeology. The application of this toolset is likely to increase in popularity over coming decades due to advances in the field and a reduction in the cost of analyses. In research settings where the continued value of living trees subject to dendrochronological investigation is important, the use of an increment bore corer to extract trunk tissue is considered the best option to minimise negative impacts on tree health (e.g. stress and fitness). A small and fragmented body of literature, however, reports significant after-effects, and in some cases fatal outcomes, from this sampling technique. As it stands, the literature documenting increment bore coring (IBC) impacts lacks experimental consistency and is poorly replicated, making it difficult for prospective users of the method to assess likely tree responses to coring. This paucity of information has the potential to lead to destructive misuse of the method and also limits its safe implementation in circumstances where the risk of impacts may be appropriate. If IBC is to fulfil its potential as a method of choice across research fields, then we must first address our limited understanding of IBC impacts and provide a framework for its appropriate future use. Firstly, we review the historical context of studies examining the impacts of IBC on trees to identify known patterns, focal issues and biases in existing knowledge. IBC wound responses, particularly those that impact on lumber quality, have been the primary focus of prior studies. No universal treatment was identified that conclusively improved wound healing and few studies have linked wound responses to tree health impacts. Secondly, we build on literature insights using a theoretical approach to identify the most important factors to guide future research involving implementation of IBC, including innate tree characteristics and environmental factors. Thirdly, we synthesise and interrogate the quantitative data available through meta-analysis to identify risk factors for wound reactions. Although poor reporting standards, restricted scopes and a bias towards temperate ecosystems limited quantitative insight, we found that complete cambial wound closure could still harbour high rates of internal trunk decay, and that conditions favouring faster growth generally correlated with reduced indices of internal and external damage in broadleaved taxa. Finally, we propose a framework for guiding best-practice application of IBC to address knowledge gaps and maximise the utility of this method, including standardised reporting indices for identifying and minimising negative impacts on tree health. While IBC is an underutilised tool of ecological enquiry with broad applicability, the method will always incur some risk of negative impacts on the cored tree. We caution that the decision to core, or not to core, must be given careful consideration on a case-by-case basis. In time, we are confident that this choice will be better informed by evidence-based insight.

Gravel-bed rivers featuring a near dynamic equilibrium state usually display a good correspondence between geomorphological and riparian community gradients, whereas long-term human alterations may disrupt these patterns. The aim of this study was to investigate the distribution of woody riparian vegetation on three geomorphic units - floodplains, bars, and islands along the Piave River, a gravel-bed river located in Northern Italy suffering from various degrees of human pressure and disturbances. A total of 214 plots (4×4 m) along three cross sections in each of two sub-reaches of the river were surveyed in order to identify the different morphological units, dendrological characteristics of standing plants, and species composition. Three riparian woody communities, with decreasing woody species richness and tree size, were identified by cluster analysis: Alnion incanae (n=58), Salicion eleagni (n=52), and Rhamno-Prunetea (n=27). The first was significantly associated with floodplains and the others with bars. No community showed a relatively stronger association with islands. Linear mixed models showed that the three geomorphic units significantly differed in mean elevation, fine sediment depth, and geomorphic persistence, but not all Tukey contrasts were significant, and absolute differences in mean elevation above talweg were quite small (