Contested novel ecosystems: Socio-ecological processes and evidence from Italy

In the context of contemporary global climate and environmental change, both natural and social scientists have stressed the role green areas play in global warming adaptation strategies and in improving the healthiness of the urban environment. Indeed, in recent years these spaces have become central to institutional political debates and various policies have been designed for their valorization. However, little attention has been paid to rewilded urban spaces, recently defined as novel urban ecosystems, and to their socio-ecological complexity. By adopting an interdisciplinary approach that links natural and social science perspectives, this article aims to highlight the role of novel urban ecosystems in the reconfiguration of urban policies. Indeed, this contribution analyzes ecosystem services coupled with the hybrid, contested socio-ecological nature of four case studies in Italy characterized by grassroots socio-environmental mobilization. Data were collected through comparative quantitative and qualitative methods. The evidence shows that the specific ecological features of novel urban ecosystems are strategic in terms of actual and potential ecosystem service provision for cities and suggests that citizens play a fundamental role in recognizing and valorizing them. In parallel, these spaces, reconceptualized as contested novel ecosystems, emerge as controversial hybrid urban socio-natures that enable community empowerment and produce a heterogeneous, grassroots political space oriented towards urban commons and environmental-climate justice

Where are we now with European forest multi-taxon biodiversity and where can we head to?

The European biodiversity and forest strategies rely on forest sustainable management (SFM) to conserve forest biodiversity. However, current sustainability assessments hardly account for direct biodiversity indicators. We focused on forest multi-taxon biodiversity to: i) gather and map the existing information; ii) identify knowledge and research gaps; iii) discuss its research potential. We established a research network to fit data on species, standing trees, lying deadwood and sampling unit description from 34 local datasets across 3591 sampling units. A total of 8724 species were represented, with the share of common and rare species varying across taxonomic classes: some included many species with several rare ones (e.g., Insecta); others (e.g., Bryopsida) were represented by few common species. Tree-related structural attributes were sampled in a subset of sampling units (2889; 2356; 2309 and 1388 respectively for diameter, height, deadwood and microhabitats). Overall, multi-taxon studies are biased towards mature forests and may underrepresent the species related to other developmental phases. European forest compositional categories were all represented, but beech forests were over-represented as compared to thermophilous and boreal forests. Most sampling units (94%) were referred to a habitat type of conservation concern. Existing information may support European conservation and SFM strategies in: (i) methodological harmonization and coordinated monitoring; (ii) definition and testing of SFM indicators and thresholds; (iii) data-driven assessment of the effects of environmental and management drivers on multi-taxon forest biological and functional diversity, (iv) multi-scale forest monitoring integrating in-situ and remotely sensed information

Il paesaggio silvo-pastorale: cambiamenti, memoria e gestione

Il contributo intende stimolare una discussione sui rapporti tra pianificazione e gestione del patrimonio silvo-pastorale e la diversit\ue0 biologica, a diverse scale di valutazione. Il declino dell'uso agro-pastorale delle regioni montane alpine, cui ha fatto seguito l\u2019avanzamento del bosco, ha causato cambiamenti ai paesaggi tradizionali con diverse conseguenze sulla conservazione dei prati montani e sui servizi ecosistemici ad essi associati. Il contributo presenta un\u2019esperienza di studio e interpretazione dell'effetto dell\u2019abbandono della gestione tradizionale sulla diversit\ue0 delle piante dei prati, considerando i cambiamenti della copertura del suolo avvenuti negli ultimi decenni e valutando l'effetto della configurazione ecologica, topografica, gestionale e paesaggistica. Le aree di studio corrispondo alla Val di Pejo e alla Val Pesio, simili in quanto a storia dell'uso del suolo e rappresentative delle condizioni di gestione delle Alpi italiane occidentali e orientali. La superficie totale dei prati \ue8 diminuita del 54% e 91% rispettivamente in Val di Pesio (Alpi Occidentali) e in Val di Pejo (Alpi Centrali, Parco dello Stelvio). L'effettiva ricchezza delle specie dei prati \ue8 stata per lo pi\uf9 influenzata da fattori ecologici, come quantit\ue0 di luce, umidit\ue0 e reazione del suolo, quindi da caratteristiche topografiche, in particolare dalla pendenza, e infine dall'intensit\ue0 della gestione. I fattori del paesaggio hanno esercitato un effetto moderato sulla diversit\ue0 delle piante. Anche se nella Val di Pesio la conservazione di numerose attivit\ue0 di pascolo ha contribuito a rallentare il processo di riduzione della dimensione dei prati, molti dei prati ricchi di specie sono oggi poco pascolati. Viceversa, nella Val di Pejo, nonostante l\u2019accessibilit\ue0, garantita da una fitta rete stradale, il declino della fienagione ha comportato una notevole riduzione dell'estensione dei prati. Allo stesso tempo, un uso intensivo vicino agli edifici ha ridotto la ricchezza delle specie vegetali. In conclusione, la ricchezza delle specie vegetali \ue8 debolmente correlata alla dimensione dei prati e alla configurazione attuale e storica del paesaggio, che hanno un'importanza relativamente inferiore rispetto ai fattori ecologici, topografici e di gestione, quando valutati a livello di singolo prato

Wild woodlands across Italian cities: their potential role in urban regeneration

Wild urban woodlands are the result of spontaneous recolonization by plants of abandoned areas within urban and peri-urban areas. Compared to some European metropolitan areas, in Italy this \u201cunconventional\u201d nature is usually not considered in urban plans as part of the green infrastructure. We use several case studies spread throughout Italian cities to describe the variability of wild urban woodlands. We analyse, through the use of historical images and comparing results from urban planning tools, their evolution within the urban matrix. We couple this analysis with that of the structural features of these woodlands to outline their potential role in urban plans and regeneration process. Regardless of their consideration in the planning process, wild urban woodlands enhance cities\u2019 capacity of providing complementary ecosystem services and support a variety of flora and fauna that have been disappearing in urban environments. Furthermore, these areas have an overlooked potential as new spaces for educational and artistic activities, as well as for providing climate change adaptation opportunities. Therefore, one urgent challenge for city planning, in Italy as well as in many other countries, is to consider these areas as integral parts of the urban green infrastructure. Indeed, urban regeneration approaches should take into account the intrinsic dynamic conditions and the range of ecosystem services provided to citizens by these woodlands. Consequently different forest management approaches should be developed to promote a variety of outcomes in terms of ecosystem services and to guarantee the sustainability of maintaining these areas over a medium and long term

Capacity development challenges and solutions for Natura 2000: an approach through blended learning

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

Assessment of hedge stand types as determinants of woody species richness in rural field margins

The woody component along field edges often provides the only permanent elements of structural and biological diversity in landscapes that have lost much of their naturalness to agriculture and urban use. The main aims of this study were (i) to investigate how four hedge stand types, i.e., systems of management distinguished on the basis of the natural and managed growth forms of trees and shrubs (low single-storied, high single-storied, two-storied and multi-storied), differ in their biometric parameters and (ii) to identify the primary management-related determinants of native woody species richness. The study used a large dataset of hedgerows (n=538) sampled in seven sites in Northern Italy. The four hedge stand types exhibited highly significant differences in size and biometric parameters. The multi-storied hedges, associated with the highest stand structural diversity index values, supported the highest number of tree species, followed by high single-storied hedges. The low single-storied hedge stand type contained the lowest number of species. We found a positive effect of hedge area as well as a marginal negative effect of basal area on native woody species richness. The management implications addressed by our study include conversion of single-storied into two- or multi-storied types, increasing hedge size and controlling hedge stand basal area

Effects of Robinia pseudoacacia in Natura 2000 sites in Italy: a comparison with Castanea sativa woods

Robinia pseudoacacia is the most commonly spread and well-known alien species forming forests in Europe. Many of these forests are found within protected areas (e.g. Natura 2000 sites). However, little is known of the specific impacts that this species can have on the structure and functions of protected natural and semi-natural habitats. In this study we report results from an investigation of paired plots dominated by black locust and chestnut within the Natura 2000 network in the Veneto region (north-eastern Italy). Paired plots have a minimum distance of 1 km and are a commonly applied sampling method for studying effects of invasive species. We surveyed and analysed vascular plant species composition and forest structure. Management was also recorded by differentiating between coppiced and abandoned stands. Results are discussed with reference to the possible effects on biodiversity and structural and functional changes as those derived from variations in snags and logs quantity. These outcomes can help to indicate possible guidelines for the application of prevention and management actions to contrast the threat posed by invasive alien tree species

Using bioacoustics to assess the presence and species richness of owls and woodpeckers in two differently managed Alpine forests

Woodpeckers and owls are considered important forest naturalness indicators and their presence reflects those of numerous other forest-dwelling species. Because of their habits and behaviour, they are often difficult to detect, and therefore the implementation of the bioacoustics discipline is suited to the survey of such taxa. In the present study we collected data about the presence and species richness of owls and woodpeckers in relation to the main forest structure and composition variables (basal area, dominant height, tree species diversity, living trees’ vegetational conditions, canopy closure percentage, total deadwood volume, decomposition stage) in two forest sites which share similar ecological characteristics, but differ in terms of management: Cajada (non-intensively managed) and Tovanella (abandoned). Both Cajada and Tovanella forests report the presence of bird species belonging to the taxa of woodpeckers and owls. The main explanatory factors for the higher number of contacts of woodpecker and owls in Cajada rather than in Tovanella are the decomposition stage of deadwood and the level of canopy closure. Management practices in Tovanella have been only recently abandoned we think that our results might change in the future. Therefore, further research is needed, also to better assess how sustainable forest management might conserve key forest feature which are crucial for the thriving of most demanding owls and woodpeckers