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Pubblicazioni Scientifiche
Filtri di ricerca 4 risultati
Pubblicazioni per anno
LAIr: an R package to estimate LAI from Normalized Difference Vegetation Index
Bajocco
,
Sofia
,
Ferrara
,
Carlotta
,
Savian
,
Francesco
,
Ginaldi
,
Fabrizio
,
Puletti
,
Nicola
,
Crecco
,
Lorenzo
,
Bregaglio
,
Simone Ugo Maria
,
Chianucci
,
Francesco
Mostra abstract
Leaf area index (LAI) is an important biophysical parameter describing vegetation. LAI is typically retrieved from optical remote sensing by empirical models relating LAI to vegetation indices, such as the Normalized Difference Vegetation Index (NDVI). As the relationship between LAI and NDVI is non-linear and crop type dependant, several specific empirical equations relating LAI to NDVI have been developed using field data. This study presented LAIr, an R package to derive LAI from NDVI data from the most comprehensive library of conversion equations. In the package, the range of functions differs on environmental factors, sensors, and vegetation types, allowing flexibility in choosing appropriate options based on specific application, scale of investigation and data availability. We illustrated the use of the package with a case study to compare a generic LAI product with specific NDVI-based LAI estimations. By leveraging empirical knowledge, LAIr enables accurate and context-specific estimation of LAI. The deployment of an open-source R package serves as a valuable tool for aiding researchers in selecting the most appropriate equations for conducting NDVI-to-LAI conversion. © 2024
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
Silvicultural regime shapes understory functional structure in European forests
Chianucci
,
Francesco
,
Napoleone
,
Francesca
,
Ricotta
,
Carlo
,
Ferrara
,
Carlotta
,
Fusaro
,
Lina
,
Balducci
,
Lorenzo
,
Trentanovi
,
Giovanni
,
Bradley
,
Owen
,
Kovács
,
Bence
,
Mina
,
Marco
,
Cerabolini
,
Bruno Enrico Leone
,
Vandekerkhove
,
Kris
,
de Smedt
,
Pallieter
,
Lens
,
Luc
,
Hertzog
,
Lionel R.
,
Verheyen
,
Kris
,
Hofmeister
,
Jeňýk
,
Hošek
,
Jan
,
Matula
,
Radim
,
Doerfler
,
Inken
,
Müller
,
Jörg C. C.
,
Weisser
,
Wolfgang W.
,
Helback
,
Jan
,
Schall
,
Peter
,
Fischer
,
Markus
,
Heilmann-Clausen
,
Jacob
,
Riis-Hansen
,
Rasmus
,
Goldberg
,
Irina
,
Aude
,
Erik
,
Kepfer-Rojas
,
Sebastian
,
Kappel Schmidt
,
Inger
,
Riis-Nielsen
,
Torben
,
Mårell
,
Anders
,
Dumas
,
Yann
,
Janssen
,
Philippe
,
Paillet
,
Yoan
,
Archaux
,
Frédéric
,
Xystrakis
,
Fotios
,
Tinya
,
Flóra
,
Ódor
,
Péter
,
Aszalós
,
Réka
,
Bölöni
,
János
,
Cutini
,
Andrea
,
Bagella
,
Simonetta
,
Sitzia
,
Tommaso
,
Brazaitis
,
Gediminas
,
Marozas
,
Vitas
,
Ujházyová
,
Mariana
,
Ujházy
,
Karol
,
Máliš
,
František
,
Nordén
,
Björn
,
Burrascano
,
Sabina
functional diversity
functional redundancy
forest understory
sustainable forest management
unmanaged forests
ecosystem resilience
silvicultural regime
Mostra abstract
Managing forests to sustain their diversity and functioning is a major challenge in a changing world. Despite the key role of understory vegetation in driving forest biodiversity, regeneration and functioning, few studies address the functional dimensions of understory vegetation response to silvicultural management. We assessed the influence of the silvicultural regimes on the functional diversity and redundancy of European forest understory. We gathered vascular plant abundance data from more than 2000 plots in European forests, each associated with one out of the five most widespread silvicultural regimes. We used generalized linear mixed models to assess the effect of different silvicultural regimes on understory functional diversity (Rao's quadratic entropy) and functional redundancy, while accounting for climate and soil conditions, and explored the reciprocal relationship between three diversity components (functional diversity, redundancy and dominance) across silvicultural regimes through a ternary diversity diagram. Intensive silvicultural regimes are associated with a decrease in functional diversity and an increase in functional redundancy, compared with unmanaged conditions. This means that although intensive management may buffer communities' functions against species or functional losses, it also limits the range of understory response to environmental changes. Policy implications. Different silvicultural regimes influence different facets of understory functional features. While unmanaged forests can be used as a reference to design silvicultural practices in compliance with biodiversity conservation targets, different silvicultural options should be balanced at landscape scale to sustain the multiple forest functions that human societies are increasingly demanding. © 2024 The Author(s). Journal of Applied Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.
The Relationship Between Maturation Size and Maximum Tree Size From Tropical to Boreal Climates
Journé
,
Valentin
,
Bogdziewicz
,
Michał
,
Courbaud
,
Benoít
,
Kunstler
,
Georges
,
Qiu
,
Tong
,
Aravena Acuña
,
Marie Claire
,
Ascoli
,
Davide
,
Bergeron
,
Yves
,
Berveiller
,
Daniel
,
Boivin
,
Thomas
,
Bonal
,
Raúl
,
Caignard
,
Thomas
,
Cailleret
,
Maxime
,
Calama
,
Rafael A.
,
Camarero
,
Jesús Julio
,
Chang-Yang
,
Chia Hao
,
Chave
,
Jérôme
,
Chianucci
,
Francesco
,
Curt
,
Thomas
,
Cutini
,
Andrea
,
Das
,
Adrian J.
,
Daskalakou
,
Evangelia N.
,
Davi
,
Hendrik
,
Delpierre
,
Nicolas
,
Delzon
,
Sylvain
,
Dietze
,
Michael C.
,
Calderon
,
Sergio Donoso
,
Dormont
,
Laurent
,
Espelta
,
Josep Maria
,
Farfan-Rios
,
William R.
,
Fenner
,
Michael
,
Franklin
,
Jerry F.
,
Gehring
,
Catherine A.
,
Gilbert
,
Gregory S.
,
Gratzer
,
Georg
,
Greenberg
,
Cathryn H.
,
Guignabert
,
Arthur
,
Guo
,
Qinfeng
,
Hacket-Pain
,
Andrew J.
,
Hampe
,
Arndt
,
Han
,
Qingmin
,
Hanley
,
Mick E.
,
Hille Ris Lambers
,
Janneke
,
Holik
,
Jan
,
Hoshizaki
,
K.
,
Ibáñez
,
Inés
,
Johnstone
,
Jill F.
,
Knops
,
Johannes Michael Hubertus
,
Kobe
,
Richard K.
,
Kurokawa
,
Hiroko
,
Lageard
,
Jonathan G.A.
,
LaMontagne
,
Jalene M.
,
Ledwoń
,
Mateusz
,
Lefèvre
,
François
,
Leininger
,
Theodor D.
,
Limousin
,
Jean Marc
,
Lutz
,
James A.
,
Macias
,
Diana S.
,
Mårell
,
Anders
,
McIntire
,
Eliot J.B.
,
Moran
,
Emily V.
,
Motta
,
Renzo
,
Myers
,
Jonathan A.
,
Nagel
,
Thomas A.
,
Naoe
,
Shoji
,
Noguchi
,
Mahoko
,
Norghauer
,
Julian M.
,
Oguro
,
Michio
,
Ourcival
,
Jean Marc
,
Parmenter
,
Robert R.
,
Pearse
,
Ian S.
,
Pérez-Ramos
,
Ignacio M.
,
Piechnik
,
Łukasz
,
Podgórski
,
Tomasz
,
Poulsen
,
John R.
,
Redmond
,
Miranda D.
,
Reid
,
Chantal D.
,
Šamonil
,
Pavel
,
Scher
,
C. Lane
,
Schlesinger
,
William H.
,
Seget
,
Barbara
,
Sharma
,
Shubhi
,
Shibata
,
Mitsue
,
Silman
,
Miles R.
,
Steele
,
Michael A.
,
Stephenson
,
Nathan L.
,
Straub
,
Jacob N.
,
Sutton
,
Samantha
,
Swenson
,
Jennifer J.
,
Swift
,
Margaret
,
Thomas
,
Peter A.
,
Uríarte
,
María
,
Vacchiano
,
Giorgio
,
Whipple
,
Amy Vaughn
,
Whitham
,
Thomas G.
,
Wright
,
Stuart Joseph
,
Zhu
,
Kai
,
Zimmerman
,
Jess K.
,
Żywiec
,
Magdalena
,
Clark
,
James S.
Mostra abstract
The fundamental trade-off between current and future reproduction has long been considered to result in a tendency for species that can grow large to begin reproduction at a larger size. Due to the prolonged time required to reach maturity, estimates of tree maturation size remain very rare and we lack a global view on the generality and the shape of this trade-off. Using seed production from five continents, we estimate tree maturation sizes for 486 tree species spanning tropical to boreal climates. Results show that a species' maturation size increases with maximum size, but in a non-proportional way: the largest species begin reproduction at smaller sizes than would be expected if maturation were simply proportional to maximum size. Furthermore, the decrease in relative maturation size is steepest in cold climates. These findings on maturation size drivers are key to accurately represent forests' responses to disturbance and climate change. © 2024 John Wiley & Sons Ltd.