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Pubblicazioni Scientifiche
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Pubblicazioni per anno
Masting is uncommon in trees that depend on mutualist dispersers in the context of global climate and fertility gradients
Qiu
,
Tong
,
Aravena Acuña
,
Marie Claire
,
Ascoli
,
Davide
,
Bergeron
,
Yves
,
Bogdziewicz
,
Michał
,
Boivin
,
Thomas
,
Bonal
,
Raúl
,
Caignard
,
Thomas
,
Cailleret
,
Maxime
,
Calama
,
Rafael A.
,
Calderon
,
Sergio Donoso
,
Camarero
,
Jesús Julio
,
Chang-Yang
,
Chia Hao
,
Chave
,
Jérôme
,
Chianucci
,
Francesco
,
Courbaud
,
Benoít
,
Cutini
,
Andrea
,
Das
,
Adrian J.
,
Delpierre
,
Nicolas
,
Delzon
,
Sylvain
,
Dietze
,
Michael C.
,
Dormont
,
Laurent
,
Espelta
,
Josep Maria
,
Fahey
,
Timothy J.
,
Farfan-Rios
,
William R.
,
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
,
Holik
,
Jan
,
Hoshizaki
,
K.
,
Ibáñez
,
Inés
,
Johnstone
,
Jill F.
,
Journé
,
Valentin
,
Kitzberger
,
Thomas A.
,
Knops
,
Johannes Michael Hubertus
,
Kunstler
,
Georges
,
Kurokawa
,
Hiroko
,
Lageard
,
Jonathan G.A.
,
LaMontagne
,
Jalene M.
,
Lefèvre
,
François
,
Leininger
,
Theodor D.
,
Limousin
,
Jean Marc
,
Lutz
,
James A.
,
Macias
,
Diana S.
,
Mårell
,
Anders
,
McIntire
,
Eliot J.B.
,
Moore
,
Christopher M.
,
Moran
,
Emily V.
,
Motta
,
Renzo
,
Myers
,
Jonathan A.
,
Nagel
,
Thomas A.
,
Naoe
,
Shoji
,
Noguchi
,
Mahoko
,
Oguro
,
Michio
,
Parmenter
,
Robert R.
,
Pearse
,
Ian S.
,
Pérez-Ramos
,
Ignacio M.
,
Piechnik
,
Łukasz
,
Podgórski
,
Tomasz
,
Poulsen
,
John R.
,
Redmond
,
Miranda D.
,
Reid
,
Chantal D.
,
Rodman
,
Kyle C.
,
Rodríguez-Sánchez
,
Francisco
,
Šamonil
,
Pavel
,
Sanguinetti
,
Javier D.
,
Scher
,
C. Lane
,
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.
,
Wion
,
Andreas P.
,
Wright
,
Stuart Joseph
,
Zhu
,
Kai
,
Zimmerman
,
Jess K.
,
Żywiec
,
Magdalena
,
Clark
,
James S.
Mostra abstract
The benefits of masting (volatile, quasi-synchronous seed production at lagged intervals) include satiation of seed predators, but these benefits come with a cost to mutualist pollen and seed dispersers. If the evolution of masting represents a balance between these benefits and costs, we expect mast avoidance in species that are heavily reliant on mutualist dispersers. These effects play out in the context of variable climate and site fertility among species that vary widely in nutrient demand. Meta-analyses of published data have focused on variation at the population scale, thus omitting periodicity within trees and synchronicity between trees. From raw data on 12 million tree-years worldwide, we quantified three components of masting that have not previously been analysed together: (i) volatility, defined as the frequency-weighted year-to-year variation; (ii) periodicity, representing the lag between high-seed years; and (iii) synchronicity, indicating the tree-to-tree correlation. Results show that mast avoidance (low volatility and low synchronicity) by species dependent on mutualist dispersers explains more variation than any other effect. Nutrient-demanding species have low volatility, and species that are most common on nutrient-rich and warm/wet sites exhibit short periods. The prevalence of masting in cold/dry sites coincides with climatic conditions where dependence on vertebrate dispersers is less common than in the wet tropics. Mutualist dispersers neutralize the benefits of masting for predator satiation, further balancing the effects of climate, site fertility and nutrient demands. © 2023, The Author(s), under exclusive licence to Springer Nature Limited.
Review of ground and aerial methods for vegetation cover fraction (fCover) and related quantities estimation: definitions, advances, challenges, and future perspectives
Li
,
Linyuan
,
Mu
,
Xihan
,
Jiang
,
Hailan
,
Chianucci
,
Francesco
,
Hu
,
Ronghai
,
Song
,
Wanjuan
,
Qi
,
Jianbo
,
Liu
,
Shouyang
,
Zhou
,
Jiaxin
,
Chen
,
Ling
,
Huang
,
Huaguo
,
Yan
,
Guangjian
airborne remote sensing
fcover
ground measurements
image and lidar
unmanned aerial vehicle (uav)
“cover” attribute
Mostra abstract
Vegetation cover fraction (fCover) and related quantities are basic yet critical vegetation structure variables in various disciplines and applications. Ground- and aerial-based proximal and remote sensing techniques have been widely adapted across multiple spatial extents. However, the definitions of fCover-related nomenclatures have not yet been fully standardized, leading to confusing terms and making comparing historic measures difficult. With the issues potentially arising from an increasing diversity of fCover and related quantities estimation methods and corresponding uncertainties, there is also a growing need to spread knowledge on the current advances, challenges, and perspectives, especially in the context of no such existing review for ground- and aerial- based estimation. This paper provides the current knowledge mainly concerning passive image-based methods and active light detection and ranging (LiDAR) -based methods. We first harmonized the definitions of fCover and its related quantities (e.g., effective canopy cover, crown cover, stratified vegetation cover, and canopy fraction). Secondly, the typical applications of fCover and related quantities over a range of scales, fields, and ecosystems were summarized. Thirdly yet importantly, we offered a comprehensive review of traditional non-imaging methods, image-based methods (e.g., segmentation, unmixing, and spectral retrieval), point cloud-based methods (e.g., rasterization), and LiDAR return-based methods (e.g., return number index and return intensity retrieval) across different platforms (i.e., ground, unmanned aerial vehicle (UAV) and airplane). Our investigation of fCover and related quantities estimation touches upon various vegetation ecosystems, including agriculture cropland, grassland, wetland, and forest. Finally, the current challenges and future directions were discussed, such as image signal processing under complex heterogeneous surfaces and stratified cover and non-photosynthesis cover retrieval. We, therefore, expect that this review may offer an insight into fCover and related quantities estimation and serve as a reference for remote sensing scientists, agronomists, silviculturists, and ecologists. © 2023 International Society for Photogrammetry and Remote Sensing, Inc. (ISPRS)
Linking seed size and number to trait syndromes in trees
Bogdziewicz
,
Michał
,
Aravena Acuña
,
Marie Claire
,
Andrus
,
Robert A.
,
Ascoli
,
Davide
,
Bergeron
,
Yves
,
Brveiller
,
Daniel
,
Boivin
,
Thomas
,
Bonal
,
Raúl
,
Caignard
,
Thomas
,
Cailleret
,
Maxime
,
Calama
,
Rafael A.
,
Calderon
,
Sergio Donoso
,
Camarero
,
Jesús Julio
,
Chang-Yang
,
Chia Hao
,
Chave
,
Jérôme
,
Chianucci
,
Francesco
,
Cleavitt
,
Natalie L.
,
Courbaud
,
Benoít
,
Cutini
,
Andrea
,
Curt
,
Thomas
,
Das
,
Adrian J.
,
Davi
,
Hendrik
,
Delpierre
,
Nicolas
,
Delzon
,
Sylvain
,
Dietze
,
Michael C.
,
Dormont
,
Laurent
,
Farfan-Rios
,
William R.
,
Gehring
,
Catherine A.
,
Gilbert
,
Gregory S.
,
Gratzer
,
Georg
,
Greenberg
,
Cathryn H.
,
Guignabert
,
Arthur
,
Guo
,
Qinfeng
,
Hacket-Pain
,
Andrew J.
,
Hampe
,
Arndt
,
Han
,
Qingmin
,
Hoshizaki
,
K.
,
Ibáñez
,
Inés
,
Johnstone
,
Jill F.
,
Journé
,
Valentin
,
Kitzberger
,
Thomas A.
,
Knops
,
Johannes Michael Hubertus
,
Kunstler
,
Georges
,
Kobe
,
Richard K.
,
Lageard
,
Jonathan G.A.
,
LaMontagne
,
Jalene M.
,
Ledwoń
,
Mateusz
,
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
,
Oguro
,
Michio
,
Kurokawa
,
Hiroko
,
Ourcival
,
Jean Marc
,
Parmenter
,
Robert R.
,
Pérez-Ramos
,
Ignacio M.
,
Piechnik
,
Łukasz
,
Podgórski
,
Tomasz
,
Poulsen
,
John R.
,
Qiu
,
Tong
,
Redmond
,
Miranda D.
,
Reid
,
Chantal D.
,
Rodman
,
Kyle C.
,
Šamonil
,
Pavel
,
Holik
,
Jan
,
Scher
,
C. Lane
,
van Marle
,
Harald Schmidt
,
Seget
,
Barbara
,
Shibata
,
Mitsue
,
Sharma
,
Shubhi
,
Silman
,
Miles R.
,
Steele
,
Michael A.
,
Straub
,
Jacob N.
,
Sun
,
I. Fang
,
Sutton
,
Samantha
,
Swenson
,
Jennifer J.
,
Thomas
,
Peter A.
,
Uríarte
,
María
,
Vacchiano
,
Giorgio
,
Veblen
,
Thomas Thorstein
,
Wright
,
Boyd R.
,
Wright
,
Stuart Joseph
,
Whitham
,
Thomas G.
,
Zhu
,
Kai
,
Zimmerman
,
Jess K.
,
Żywiec
,
Magdalena
,
Clark
,
James S.
Mostra abstract
Aim: Our understanding of the mechanisms that maintain forest diversity under changing climate can benefit from knowledge about traits that are closely linked to fitness. We tested whether the link between traits and seed number and seed size is consistent with two hypotheses, termed the leaf economics spectrum and the plant size syndrome, or whether reproduction represents an independent dimension related to a seed size–seed number trade-off. Location: Most of the data come from Europe, North and Central America and East Asia. A minority of the data come from South America, Africa and Australia. Time period: 1960–2022. Major taxa studied: Trees. Methods: We gathered 12 million observations of the number of seeds produced in 784 tree species. We estimated the number of seeds produced by individual trees and scaled it up to the species level. Next, we used principal components analysis and generalized joint attribute modelling (GJAM) to map seed number and size on the tree traits spectrum. Results: Incorporating seed size and number into trait analysis while controlling for environment and phylogeny with GJAM exposes relationships in trees that might otherwise remain hidden. Production of the large total biomass of seeds [product of seed number and seed size; hereafter, species seed productivity (SSP)] is associated with high leaf area, low foliar nitrogen, low specific leaf area (SLA) and dense wood. Production of high seed numbers is associated with small seeds produced by nutrient-demanding species with softwood, small leaves and high SLA. Trait covariation is consistent with opposing strategies: one fast-growing, early successional, with high dispersal, and the other slow-growing, stress-tolerant, that recruit in shaded conditions. Main conclusions: Earth system models currently assume that reproductive allocation is indifferent among plant functional types. Easily measurable seed size is a strong predictor of the seed number and species seed productivity. The connection of SSP with the functional traits can form the first basis of improved fecundity prediction across global forests. © 2023 John Wiley & Sons Ltd.