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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
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.
Mapping Understory Vegetation Density in Mediterranean Forests: Insights from Airborne and Terrestrial Laser Scanning Integration
Mostra abstract
The understory is an essential ecological and structural component of forest ecosystems. The lack of efficient, accurate, and objective methods for evaluating and quantifying the spatial spread of understory characteristics over large areas is a challenge for forest planning and management, with specific regard to biodiversity and habitat governance. In this study, we used terrestrial and airborne laser scanning (TLS and ALS) data to characterize understory in a European beech and black pine forest in Italy. First, we linked understory structural features derived from traditional field measurements with TLS metrics, then, we related such metrics to the ones derived from ALS. Results indicate that (i) the upper understory density (5–10 m above ground) is significantly associated with two ALS metrics, specifically the mean height of points belonging to the lower third of the ALS point cloud within the voxel (HM<inf>1/3</inf>) and the corresponding standard deviation (SD<inf>1/3</inf>), while (ii) for the lower understory layer (2–5 m above ground), the most related metric is HM<inf>1/3</inf> alone. As an example application, we have produced a map of forest understory for each layer, extending over the entire study region covered by ALS data, based on the developed spatial prediction models. With this study, we also demonstrated the power of hand-held mobile-TLS as a fast and high-resolution tool for measuring forest structural attributes and obtaining relevant ecological data. © 2023 by the authors.
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
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
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.
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.