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Pubblicazioni Scientifiche

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Pubblicazioni per anno
What Is Known About the Management of European Beech Forests Facing Climate Change? A Review
Mostra abstract
Purpose of Review: This paper aims to retrace the most significant management strategies adopted across European beech forests over the last 25 years, highlighting those that are most efficient and promising. We investigate five main topics including forest management, forest models, species mixture, genetic, and regeneration. Recent Findings: European beech is one of the most widespread and important tree species for the European forest sector. In the light of the ongoing climate crisis, understanding the growth dynamics and the response of beech forests to climate change is crucial to identify advantageous management strategies. Ecology, growth, management, distribution, interaction with other species, genetic, and regeneration aspects of European beech were investigated in different geographical areas of Europe. Despite recent researches focusing on climate change issues, how adaptation and mitigation measures can be integrated into silvicultural guidelines to improve the resilience of European beech forests remains unclear. Summary: To answer this question, we collected and reviewed articles about the management of European beech facing climate change, which were published in peer-reviewed journals over the last 25 years. Articles were grouped into five geographic European areas, according to the classification used by the State of Europe’s forests. Obtained articles were further clustered into five main topics: management, mixed forest, modelling, genetic, and regeneration. The review highlighted the importance of using long-term monitoring plots to understand the effect of climate change on the stability of European beech forests, suggesting climate-smart measures that would help these forests adapt to climate change. © 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG.
Monitoring spring phenology in Mediterranean beech populations through in situ observation and Synthetic Aperture Radar methods
Mostra abstract
The interest in tree phenology monitoring is increasing because this trait is a robust indicator of the impacts of climate change on natural and managed ecosystems. Different approaches to monitor phenology at different spatial scales, from in situ monitoring to remote sensing, are used to investigate spring and/or autumn phenological changes. In Mediterranean area, most of phenological changes occur during cloudy periods (spring and autumn), leading to a loss of information also for very high temporal resolution satellites. Instead, cloud-uninfluenced sensors, such as radar sensors, can allow to bypass this problem and produce a temporally continuous coverage. In this paper, we analyzed the spring phenology of two European beech (Fagus sylvatica L.) populations, located at different latitudes in Mediterranean area. Weekly in situ monitoring of leaf-out has been correlated with data collected by Synthetic Aperture Radar. Spring phenological phases were monitored in situ following a modified BBCH-code with a 5-scores scale (from 1 - buds closed and covered by scales, to 5 - leaf completely unfolded). The score 3 (young leaves starting to emerge from the bud) was considered the bud break. Different site conditions based on aspect (northern and southern) and altitudinal gradient (high and low altitude) have been considered. The aim was to test and implement a new methodology able to decrease the frequency of the field sampling, using remote data, to extend more detailed information on geographical scale, and to reconstruct past phenology. Results showed a statistically significant different length of the vegetative spring period, spanning from dormant buds, up to leaves completely unfolded, between sites. Through Synthetic Aperture Radar estimation, this study demonstrates that leaf-out can be monitored with an extreme accuracy. The phenophase score 4 and 5 estimation showed the best performance (RMSE < of 4 days), phenophases score 2 and 3 showed promising performances (4 days < RMSE <5 days), while phenophases score 1 seems to be not easily detectable, although it can be extrapolated with an RMSE <6 days. This radar approach fixes the cloud problem typical of multispectral approach and very frequent in phenophase change periods in Mediterranean climate. This study promotes the proposed remote sensing approach as a very useful tool to monitor growing season starting in remote areas, helping to reduce in situ observations and allowing past phenology reconstruction. © 2020 Elsevier Inc.
Widespread breakdown in masting in European beech due to rising summer temperatures
Mostra abstract
Climate change effects on tree reproduction are poorly understood, even though the resilience of populations relies on sufficient regeneration to balance increasing rates of mortality. Forest-forming tree species often mast, i.e. reproduce through synchronised year-to-year variation in seed production, which improves pollination and reduces seed predation. Recent observations in European beech show, however, that current climate change can dampen interannual variation and synchrony of seed production and that this masting breakdown drastically reduces the viability of seed crops. Importantly, it is unclear under which conditions masting breakdown occurs and how widespread breakdown is in this pan-European species. Here, we analysed 50 long-term datasets of population-level seed production, sampled across the distribution of European beech, and identified increasing summer temperatures as the general driver of masting breakdown. Specifically, increases in site-specific mean maximum temperatures during June and July were observed across most of the species range, while the interannual variability of population-level seed production (CVp) decreased. The declines in CVp were greatest, where temperatures increased most rapidly. Additionally, the occurrence of crop failures and low seed years has decreased during the last four decades, signalling altered starvation effects of masting on seed predators. Notably, CVp did not vary among sites according to site mean summer temperature. Instead, masting breakdown occurs in response to warming local temperatures (i.e. increasing relative temperatures), such that the risk is not restricted to populations growing in warm average conditions. As lowered CVp can reduce viable seed production despite the overall increase in seed count, our results warn that a covert mechanism is underway that may hinder the regeneration potential of European beech under climate change, with great potential to alter forest functioning and community dynamics. © 2024 The Authors. Global Change Biology published by John Wiley & Sons Ltd.