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Pubblicazioni Scientifiche
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Pubblicazioni per anno
Performance assessment of two plotless sampling methods for density estimation applied to some Alpine forests of northeastern Italy
accuracy
conditional inference trees
distance-based density estimator
forest monitoring
ordered distance method
point-centred quarter method
precision
Mostra abstract
In this study, we tested two plotless sampling methods, the ordered distance method and point-centred quarter method, to estimate the tree density and basal area in some managed Alpine forests in northeastern Italy. We selected nine independent forest stands, classified according to the spatial distribution patterns of trees (cluster, random, regular). A plotless sampling survey was simulated within the selected stands and the tree density and basal area were estimated by applying both the ordered distance method and point-centred quarter method. We compared the estimates, in terms of accuracy and preci-sion, between the two methods and against estimates obtained from a simulated survey based on a plot-based sampling method. The point-centred quarter method outperformed the ordered distance method in terms of both accuracy and precision, showing higher robustness towards the bias related to non-random spatial patterns. However, both the plotless methods we tested can provide unbiased accuracy of estimates which, in addition, do not differ from estimates of plot-based sampling. The satisfactory results are encouraging for further tests over other Italian Alpine as well as Apennine forests. If con-firmed, the plotless sampling method, especially the point-centred quarter method, could represent an effective alternative whenever plot-based sampling is deemed redundant, or expensive. © SISEF.
Where are we now with European forest multi-taxon biodiversity and where can we head to?
Burrascano
,
Sabina
,
Chianucci
,
Francesco
,
Trentanovi
,
Giovanni
,
Kepfer-Rojas
,
Sebastian
,
Sitzia
,
Tommaso
,
Tinya
,
Flóra
,
Doerfler
,
Inken
,
Paillet
,
Yoan
,
Nagel
,
Thomas A.
,
Mitić
,
Božena
,
Morillas
,
Lourdes
,
Munzi
,
Silvana
,
Van Der Sluis
,
Theo
,
Alterio
,
Edoardo
,
Balducci
,
Lorenzo
,
de Andrade
,
Rafael Barreto
,
Bouget
,
Christophe
,
Giordani
,
P.
,
Lachat
,
Thibault
,
Matošević
,
Dinka
,
Napoleone
,
Francesca
,
Nascimbene
,
Juri
,
Paniccia
,
Chiara
,
Roth
,
Nicolas
,
Aszalós
,
Réka
,
Brazaitis
,
Gediminas
,
Cutini
,
Andrea
,
D'Andrea
,
Ettore
,
de Smedt
,
Pallieter
,
Heilmann-Clausen
,
Jacob
,
Janssen
,
Philippe
,
Kozák
,
Daniel
,
Mårell
,
Anders
,
Mikoláš
,
Martin
,
Nordén
,
Björn
,
Matula
,
Radim
,
Schall
,
Peter
,
Svoboda
,
Miroslav
,
Ujházyová
,
Mariana
,
Vandekerkhove
,
Kris
,
Wohlwend
,
Michael Rudolf
,
Xystrakis
,
Fotios
,
Aleffi
,
Michele
,
Ammer
,
Christian
,
Archaux
,
Frédéric
,
Asbeck
,
Thomas
,
N Avtzis
,
Dimitrios N.
,
Ayasse
,
Manfred
,
Bagella
,
Simonetta
,
Balestrieri
,
Rosario
,
Barbati
,
Anna
,
Basile
,
Marco
,
Bergamini
,
Ariel
,
Bertini
,
Giada
,
Biscaccianti
,
Alessandro Bruno
,
Boch
,
Steffen
,
Bölöni
,
János
,
Bombi
,
Pierluigi
,
Boscardin
,
Yves
,
Brunialti
,
Giorgio
,
Bruun
,
Hans Henrik
,
Buscot
,
François
,
Byriel
,
David Bille
,
Campagnaro
,
Thomas
,
Campanaro
,
Alessandro
,
Chauvat
,
Matthieu
,
Ciach
,
Michał
,
Čiliak
,
Marek
,
Cistrone
,
Luca
,
Pereira
,
Joaò Manuel Cordeiro
,
Daniel
,
Rolf
,
de Cinti
,
Bruno
,
de Filippo
,
Gabriele
,
Dekoninck
,
Wouter
,
Di Salvatore
,
Umberto
,
Dumas
,
Yann
,
Elek
,
Zoltán
,
Ferretti
,
Fabrizio
,
Fotakis
,
Dimitrios G.
,
Frank
,
Tamás
,
Frey
,
Julian
,
Giancola
,
Carmen
,
Gömöryová
,
Erika
,
Gosselin
,
Marion
,
Gosselin
,
Frédéric
,
Goßner
,
Martin M.
,
Götmark
,
Frank
,
Haeler
,
Elena
,
Hansen
,
Aslak Kappel
,
Hertzog
,
Lionel R.
,
Hofmeister
,
Jeňýk
,
Hošek
,
Jan
,
Johannsen
,
Vivian Kvist
,
Justensen
,
Mathias Just
,
Korboulewsky
,
Nathalie
,
Kovács
,
Bence
,
Lakatos
,
Ferenc
,
Landivar
,
Carlos Miguel
,
Lens
,
Luc
,
Lingua
,
Emanuele
forest biodiversity
biodiversity conservation
forest stand structure
multi-taxon
sustainable management
Mostra abstract
The European biodiversity and forest strategies rely on forest sustainable management (SFM) to conserve forest biodiversity. However, current sustainability assessments hardly account for direct biodiversity indicators. We focused on forest multi-taxon biodiversity to: i) gather and map the existing information; ii) identify knowledge and research gaps; iii) discuss its research potential. We established a research network to fit data on species, standing trees, lying deadwood and sampling unit description from 34 local datasets across 3591 sampling units. A total of 8724 species were represented, with the share of common and rare species varying across taxonomic classes: some included many species with several rare ones (e.g., Insecta); others (e.g., Bryopsida) were represented by few common species. Tree-related structural attributes were sampled in a subset of sampling units (2889; 2356; 2309 and 1388 respectively for diameter, height, deadwood and microhabitats). Overall, multi-taxon studies are biased towards mature forests and may underrepresent the species related to other developmental phases. European forest compositional categories were all represented, but beech forests were over-represented as compared to thermophilous and boreal forests. Most sampling units (94%) were referred to a habitat type of conservation concern. Existing information may support European conservation and SFM strategies in: (i) methodological harmonization and coordinated monitoring; (ii) definition and testing of SFM indicators and thresholds; (iii) data-driven assessment of the effects of environmental and management drivers on multi-taxon forest biological and functional diversity, (iv) multi-scale forest monitoring integrating in-situ and remotely sensed information. © 2023 The Authors
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)