Perception and management of the understorey vegetation by chestnut growers: the study case of the chestnut orchards in the Bologna and Modena Apennines (Italy)

In southern Europe, traditionally managed chestnut orchards are iconic landscapes and habitats rich in biodiversity. They consist of a spaced stand of grafted chestnut trees for fruit production and a herbaceous understorey layer. Management practises play a key role in maintaining and shaping the understorey vegetation layer, which supports most of the vegetation diversity. However, very little is known about thoughts, feelings, and attitudes of growers to the plant species which make up the understorey ground vegetation. To probe further on this issue, we performed qualitative socio-ecological research involving 38 growers to explore their perceptions and attitudes towards the understorey vegetation of selected chestnut orchards of the northern Apennines. Although most of the respondents were in their 60 s, they showed a wide range of cultural backgrounds and shared the common passion for chestnut cultivation. Biodiversity proved to be a difficult concept for the interviewees to understand and deal with. Nevertheless, the interviews based on both closed and open-ended questions made it possible to record 140 plant taxa. Among them, species with conspicuous flowers (e.g., orchids), species requiring management effort, and species providing practical benefits according to local tradition. Understanding and knowing the ecosystem complexity of the chestnut orchards could guide growers towards more adequate and biodiversity-enhancing management practises. There is, however, an urgent need to increase biodiversity awareness among chestnut growers (e.g., through training courses) to enhance and ensure the conservation of the traditional chestnut orchards and related biodiversit

Using long‐term ecological datasets to unravel the impacts of short‐term meteorological disturbances on phytoplankton communities

Extreme meteorological events such as storms are increasing in frequency and intensity, but our knowledge of their impacts on aquatic ecosystems and emergent system properties is limited. Understanding the ecological impacts of storms on the dynamics of primary producers remains a challenge that needs to be addressed to assess the vulnerability of freshwater ecosystems to extreme weather conditions and climate change. One promising approach to gain insights into storm impacts on phytoplankton community dynamics is to analyse long-term monitoring datasets. However, such an approach requires disentangling the impacts of short-term meteorological disturbances from the effects of the seasonal trajectories of meteorological conditions. To this end, we applied boosted regression tree models to phytoplankton time series from eight relatively large lakes on four continents, coupled with a procedure adapted to detect and quantify rare events. Overall, the patterns and potential drivers we identified provide important insights into the responses of lakes to short-term meteorological events and highlight differences in the response of phytoplankton communities according to lake morphological characteristics. Our results indicated that deepened thermoclines and lake-specific combinations of drivers describing altered thermal structures caused deviations from the typical trajectories of seasonal phytoplankton succession. For shallow polymictic lakes, shifts in phytoplankton succession also depended on changes in light availability. Overall, our study highlights the value of long-term monitoring to improve our understanding of phytoplankton sensitivity to short-term meteorological disturbance

No traces of emerging and priority organic pollutants in the muscles of Procambarus clarkii suggest the feasibility of its regulated and sustainable control from uncontaminated environments

A monitoring of organic contaminants in the muscles of the Procambarus clarkii and environmental samples of water and sediment was conducted in three Sicilian wetlands (Italy). The substances investigated in the bio- logical samples were per- and polyfluoroalkyl substances (PFAS), phthalic acid esters (PAEs), pesticides, anti- biotics, and microcystins (MCs), all of which were below the detection limit. Given that the Louisiana red swamp crayfish is considered a bioaccumulator, the results of this study indicate that these environments are not significantly contaminated by the selected pollutants. Furthermore, the study suggests the potential uses of the edible portions of this alien species. Despite P. clarkii cannot be marketed in several countries, including Italy, it is possible that the animal biomass obtained in the frame of the monitoring, control and eradication activities carried out by local authorities, could be exploited for various purposes, such as food, feed and biotechnology. This would reduce the costs associated with disposal and make these activities more sustainable in the long term, thereby contributing to the preservation of ecosystems that are currently threatened by this invasive species

Behaviour of brown bears under fluctuating resource availability

Mast seeding, the variable and intermittent production of seeds, has cascading effects on ecosystem functioning. This study explores its influence on the brown bear populations in the Italian Alps, focusing on beechnuts (Fagus sylvatica L.), the primary food source for bears in the region. Using historical data and field sampling, we estimated and mapped the annual seed biomass from 2007 to 2021 for the province of Trento. The energy content of beechnuts was assessed through high heating values, providing the caloric resources available. Data on beechnuts production, records of damages and GPS data from 16 Eurasian brown bears were integrated to perform a temporal and spatial analysis at home range and at landscape level. Standardised damages to beehives and livestock decreased during mast years, suggesting that bears met their trophic needs through natural food sources. In fact, bears used more agricultural areas and less beech forest during years of beech crop failure. At landscape level, agriculture and pasture areas close to beech forests and distant from cities showed a higher risk of damage, providing a tool to anticipate management actions. This work provides insights on the ecological dynamics and conservation implications of brown bears in the study area by mapping the spatial and temporal aspects of mast seeding and bear-related damage

Towards a global understanding of tree mortality

Rates of tree mortality are increasing globally, with implications for forests and climate. Yet, how and why these trends vary globally remain unknown. Developing a comprehensive assessment of global tree mortality will require systematically integrating data from ground-based long-term forest monitoring with large-scale remote sensing. We surveyed the metadata from 466 865 forest monitoring plots across 89 countries and five continents using questionnaires and discuss the potential to use these to estimate tree mortality trends globally. Our survey shows that the area monitored has increased steadily since 1960, but we also identify many regions with limited ground-based information on tree mortality. The integration of existing ground-based forest inventories with remote sensing and modelling can potentially fill those gaps, but this requires development of technical solutions and agreements that enable seamless flows of information from the field to global assessments of tree mortality. A truly global monitoring effort should promote fair and equitable collaborations, transferring funding to and empowering scientists from less wealthy regions. Increasing interest in forests as a natural climate solution, the advancement of new technologies and world-wide connectivity means that now a global monitoring system of tree mortality is not just urgently needed but also possibl

Rapid profiling of volatile organic compounds associated with plant-based milks versus bovine milk using an integrated PTR-ToF-MS and GC-MS approach

The growing demand for plant-based beverages has underscored the importance of investigating their volatile profiles, which play a crucial role in sensory perception and consumer acceptance. This is especially true for plant-based milks (PBMs) that have a clear reference model in bovine milk. This study characterises the volatile organic compounds (VOCs) in soy, almond and oat beverages compared to bovine milk using proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS) as a rapid and noninvasive screening tool, complemented by gas chromatography-mass spectrometry (GC-MS) for compound identification. A total of 188 mass peaks were detected by PTR-ToF-MS, all showing significant differences from the blank, while GC-MS allowed the identification of 50 compounds, supporting the tentative identifications performed with PTR-MS analysis. In order to facilitate a comparison of different milks, after statistical analysis, these 188 mass peaks were further categorised into two groups: one consisting of VOCs with minimal variability across all samples and another comprising VOCs with significantly different abundances, distinctly characterising each beverage. Principal component analysis revealed a clear separation between bovine milk and PBMs, with almond beverages exhibiting the richest volatilome, while oat beverages displayed a more homogeneous volatile profile. PTR-ToF-MS demonstrated its ability to analyse volatile profiles rapidly, with excellent complementarity to GC-MS in terms of analytical versatility. The results provided a valuable basis for testing new experimental designs aimed to characterise and enhance flavour profiles in plant-based beverages, also after processing, in case of new product development that considers using these milks as raw material

Cultivar fingerprinting and SNP-based pedigree reconstruction in Danish heritage apple cultivars utilizing genotypic data from multiple germplasm collections in the world

Heirloom Danish apple cultivars are historically and pomologically important, part of the cultural heritage, and have valuable adaptation to regional climate conditions. However, lack of information about their genetic identity and pedigree relatedness with other cultivars hampers proper cultivar identification, germplasm curation, genebank management, and future regional breeding efforts. Many Danish apple cultivars are maintained in the national collection “The Pometum”, maintaining around 850 apple accessions. Additional material is maintained in public or private Danish collections. However, no information exists regarding genotypic duplicates between these collections and germplasm collections in other countries, pedigree inferences across collections, and genotypically unique accessions at the genebank level. To provide such information, 976 accessions from Denmark were genotyped with simple sequence repeat (SSR) markers and the Illumina Infinium 20K single nucleotide polymorphism (SNP) array. The resulting genotypic data were compared to large databases of genotypic data from germplasm collections in multiple countries to identify genotypic duplicates and conduct pedigree reconstruction. The germplasm maintains 305 unique genotypic profiles which were not found in other germplasm collections. The study exposed previously unknown synonyms, accessions not true-to-type, and novel pedigree relationships involving accessions from multiple collection sites. The most frequent parents of Danish germplasm were ‘Hvid Vinter Pigeon’ and ‘Cox’s Orange Pippin’ whereas ‘Reinette Franche’ was the most common grandparent. The accession-level information will benefit germplasm curation, cultivar identification, genebank management, and future breeding efforts, and shed new light on cultivar history and origi

Epidemiological studies on primary inoculum of Venturia inaequalis and V. asperata for apple scab management

Apple scab, caused by the ascomycete Venturia inaequalis, is the most important disease of apple, causing great losses worldwide. Its management is largely based on fungicide treatments, especially targeting ascosporic infections. To reduce the pesticide input, sanitation practices against overwintering inoculum, decision support systems for an optimal timing of treatments, and resistant cultivars can be used. However, reducing pesticide pressure increases the risk of emerging new and/or secondary pathogens. This is the case of V. asperata that was isolated on cultivars resistant to V. inaequalis and already reported in several regions of Italy and France. It causes atypical scab-spots on fruit and leaves. Limited information is available on the epidemiology of V. asperata. The specific objectives of the thesis were: i) to set up a method of reducing the overwintering inoculum of apple scab by irrigating overwintering leaves on the ground in dry days, ii) to understand the aerial dispersal of ascospores with the under-canopy irrigation, and iii) to identify the conditions of maturation of pseudothecia and ascospore discharge of V. asperata. The effect of irrigation was evaluated comparing irrigated and non-irrigated leaf litter. Irrigation in dry days induced the release of a noticeable amount of ascospores of V. inaequalis under conditions unsuitable for infection, thus reducing the inoculum during rainy days. In mean of all trials, the ascosporic inoculum was reduced by approx. 50% in irrigated plots. In addition, irrigation caused an earlier depletion of the ascospore supply. Field trials were carried out to evaluate the efficacy of irrigation in reducing scab in untreated and fungicide-treated plots. By the end of the primary season, the overall incidence of infected leaves and fruit in untreated and fungicide-treated plots had decreased by more than 50%. To understand the aerial dispersal of ascospores of V. inaequalis with under-canopy irrigation, rotating-arm spore traps were placed at heights, ranging from 0.3 m to 3.0 m above the ground. Irrigation was carried out above overwintered apple leaves infected with scab in two different situations, i.e., in a wind-protected enclosure and under real orchard conditions. Ascospores were found to disperse above the irrigated layer, with more spores detected above the sprinklers than below. Based on these results, since ascospores could settle on susceptible apple tissues, it is essential to ensure a rain-free period of at least 24 hours post-irrigation to prevent scab infections. The primary infection season of V. asperata was studied by comparing the development of pseudothecia and ascospore discharge to V. inaequalis in overwintered leaf litters. Venturia asperata showed a delay in pseudothecial maturation and emptying in relation to degree days accumulation, compared to V. inaequalis. The time of spore release for V. asperata was postponed compared to V. inaequalis. The delayed spore ejection and pseudothecial development of V. asperata, in comparison with V. inaequalis, could partly explain the late appearance of symptoms during the growing season in the orchards. In conclusion, targeted irrigation could represent a sustainable and easily applicable method to reduce the incidence of apple scab, and consequently to reduce the number of treatments or increasing their efficacy. Further research on epidemiology of V. asperata is necessary to find the optimal weather conditions for ascospore discharge and for primary and secondary infections, as well as its latency period. Future breeding programs for apple should also take into consideration resistance against V. asperat

Restoring genetic diversity to facilitate the implementation of the EU Nature Restoration Law

Governments and economic blocs are recognising that the world faces a biodiversity crisis. The restoration of biodiversity to the levels prior to widespread human induced damage has been incorporated as a crucial component of conservation in the Global Biodiversity Framework of the Convention of Biological Diversity. The Nature Restoration Law (NRL) forms part of the European Union's response and after its adoption by the European Parliament and the Council of the European Union, it has formally become the Nature Restoration Regulation (NRR). The NRL aims to play a role in restoring ecosystems, habitats and species but does not expressly include genetic diversity, the third biodiversity component. Considering genetic diversity in strategic biodiversity planning is important to help nature adapt to rapid anthropogenic change. We have reviewed the text of the NRL and note opportunities to incorporate genetic diversity in National Restoration Plans to augment its implementation. In particular, genetic diversity assessments are well aligned with the NRL's aspiration to enhance connectivity, and genetic indicators can assess the effectiveness of its implementation. Here we give examples where restoration has incorporated genetic diversity to ensure long term wide-reaching success. This is of relevance beyond the NRL and applies generally to policy for nature restoration efforts globally, especially those related to the Global Biodiversity Framewor