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Pubblicazioni Scientifiche
Filtri di ricerca 5 risultati
Pubblicazioni per anno
Multiple drivers of functional diversity in temperate forest understories: Climate, soil, and forest structure effects
Chelli
,
Stefano
,
Bricca
,
Alessandro
,
Tsakalos
,
James L.
,
Andreetta
,
Anna
,
Bonari
,
Gianmaria
,
Campetella
,
Giandiego
,
Carnicelli
,
Stefano
,
Cervellini
,
Marco
,
Puletti
,
Nicola
,
Wellstein
,
Camilla
,
Canullo
,
R.
climate change
functional diversity
bud bank
forest management
plant height
seed mass
specific leaf area
Mostra abstract
In macroecology, shifting from coarse- to local-scale explanatory factors is crucial for understanding how global change impacts functional diversity (FD). Plants possess diverse traits allowing them to differentially respond across a spectrum of environmental conditions. We aim to assess how macro- to microclimate, stand-scale measured soil properties, forest structure, and management type, influence forest understorey FD at the macroecological scale. Our study covers Italian forests, using thirteen predictors categorized into climate, soil, forest structure, and management. We analyzed five traits (i.e., specific leaf area, plant size, seed mass, belowground bud bank size, and clonal lateral spread) capturing independent functional dimensions to calculate the standardized effect size of functional diversity (SES-FD) for all traits (multi-trait) and for single traits. Multiple regression models were applied to assess the effect of predictors on SES-FD. We revealed that climate, soil, and forest structure significantly drive SES-FD of specific leaf area, plant size, seed mass, and bud bank. Forest management had a limited effect. However, differences emerged between herbaceous and woody growth forms of the understorey layer, with herbaceous species mainly responding to climate and soil features, while woody species were mainly affected by forest structure. Future warmer and more seasonal climate could reduce the diversity of resource economics, plant size, and persistence strategies of the forest understorey. Soil eutrophication and acidification may impact the diversity of regeneration strategies; canopy closure affects the diversity of above- and belowground traits, with a larger effect on woody species. Multifunctional approaches are vital to disentangle the effect of global changes on functional diversity since independent functional specialization axes are modulated by different drivers. © 2024 The Authors
Species dominance and above ground biomass in the Białowieża Forest, Poland, described by airborne hyperspectral and lidar data
Vaglio Laurin
,
Gaia
,
Puletti
,
Nicola
,
Grotti
,
Mirko
,
Stereńczak
,
Krzysztof Jan
,
Modzelewska
,
Aneta
,
Lisiewicz
,
Maciej
,
Sadkowski
,
Rafał
,
Kuberski
,
Łukasz
,
Chirici
,
Gherardo
,
Papale
,
Dario
climate change
lidar
aboveground biomass
algorithm
data set
deciduous tree
species diversity
species richness
vegetation dynamics
bialowieza forest
scolytinae
Mostra abstract
The objective of this research is to test and evaluate hyperspectral and lidar data to derive information on tree species dominance and above ground biomass in the Białowieża Forest in Poland. This forest is threatened by climate change, fire, bark beetles attacks, and logging, with changes in species composition and dominance. In this conservation valuable area, the monitoring of forest resources is thus critical. Results indicate that vegetation indices from hyperspectral data can support species dominance detection: using a Classification and Regression Trees algorithm the three main plot types (dominated by Deciduous, Spruce, and Pines species) were classified with an Overall Accuracy > 0.9. The accuracy decreased when a ‘Mixed’ group was added to account for very heterogeneous plots, and plots dominated by Spruce were not correctly detected. Hyperspectral vegetation indices were also used to estimate the level of species dominance in the forest plots, using a Multivariate Multiple Linear Regression model; the obtained accuracy varied according to groups, being higher for Deciduous (R<sup>2</sup> = 0.87), compared to Pines (R<sup>2</sup> = 0.61), and to Spruce-dominated plots (R<sup>2</sup> = 0.37). Lidar data were employed to estimate above ground biomass, using an exponential regression model; overall the R<sup>2</sup> resulted equal to 0.66 but ranged from 0.57 to 0.78 when considering subgroups according to species dominance; the addition of hyperspectral vegetation indices improved the result only for Pines. The illustrated methods provide a reliable description of important forest characteristics and simplify resource monitoring, supporting local authorities to address the challenges imposed by climate change and other forest threats. © 2020 The Authors
Monitoring spring phenology in Mediterranean beech populations through in situ observation and Synthetic Aperture Radar methods
Proietti
,
R.
,
Antonucci
,
Serena
,
Monteverdi
,
Maria Cristina
,
Garfì
,
Vittorio
,
Marchetti
,
Marco
,
Plutino
,
Manuela
,
Di Carlo
,
Marco
,
Germani
,
Andrea
,
Santopuoli
,
Giovanni
,
Castaldi
,
Cristiano
,
Chiavetta
,
U.
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.
Evolutionary ecology of masting: mechanisms, models, and climate change
Bogdziewicz
,
Michał
,
Kelly
,
Dave J.
,
Ascoli
,
Davide
,
Caignard
,
Thomas
,
Chianucci
,
Francesco
,
Crone
,
Elizabeth E.
,
Fleurot
,
Emilie
,
Foest
,
Jessie J.
,
Gratzer
,
Georg
,
Hagiwara
,
Tomika
,
Han
,
Qingmin
,
Journé
,
Valentin
,
Keurinck
,
Léa
,
Kondrat
,
Katarzyna
,
McClory
,
Ryan W.
,
LaMontagne
,
Jalene M.
,
Mundo
,
Ignacio A.
,
Nussbaumer
,
Anita
,
Oberklammer
,
Iris
,
Ohno
,
Misuzu
,
Pearse
,
Ian S.
,
Pesendorfer
,
Mario B.
,
Resente
,
Giulia
,
Satake
,
Akiko
,
Shibata
,
Mitsue
,
Snell
,
Rebecca S.
,
Szymkowiak
,
Jakub
,
Touzot
,
Laura
,
Zwolak
,
Rafał
,
Żywiec
,
Magdalena
,
Hacket-Pain
,
Andrew J.
Mostra abstract
Many perennial plants show mast seeding, characterized by synchronous and highly variable reproduction across years. We propose a general model of masting, integrating proximate factors (environmental variation, weather cues, and resource budgets) with ultimate drivers (predator satiation and pollination efficiency). This general model shows how the relationships between masting and weather shape the diverse responses of species to climate warming, ranging from no change to lower interannual variation or reproductive failure. The role of environmental prediction as a masting driver is being reassessed; future studies need to estimate prediction accuracy and the benefits acquired. Since reproduction is central to plant adaptation to climate change, understanding how masting adapts to shifting environmental conditions is now a central question. © 2024 The Authors
Widespread breakdown in masting in European beech due to rising summer temperatures
Foest
,
Jessie J.
,
Bogdziewicz
,
Michał
,
Pesendorfer
,
Mario B.
,
Ascoli
,
Davide
,
Cutini
,
Andrea
,
Nussbaumer
,
Anita
,
Verstraeten
,
Arne
,
Beudert
,
Burkhard
,
Chianucci
,
Francesco
,
Mezzavilla
,
Francesco
,
Gratzer
,
Georg
,
Kunstler
,
Georges
,
Meesenburg
,
H.
,
Wagner
,
Markus
,
Mund
,
Martina
,
Cools
,
Nathalie
,
Vacek
,
Stanislav
,
Schmidt
,
Wolfgang
,
Vacek
,
Zdeněk Ck
,
Hacket-Pain
,
Andrew J.
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.