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Forest floor alteration by canopy trees and soil wetness drive regeneration of a spruce-beech forest / Pavel Daněk in Forest ecology and management, vol 504 (January-15 2022)
[article]
Titre : Forest floor alteration by canopy trees and soil wetness drive regeneration of a spruce-beech forest Type de document : Article/Communication Auteurs : Pavel Daněk, Auteur ; Pavel Šamonil, Auteur ; Libor Hort, Auteur Année de publication : 2022 Article en page(s) : n° 119802 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] bois mort
[Termes IGN] canopée
[Termes IGN] Fagus sylvatica
[Termes IGN] humidité du sol
[Termes IGN] litière
[Termes IGN] peuplement mélangé
[Termes IGN] Picea abies
[Termes IGN] régénération (sylviculture)
[Termes IGN] République Tchèque
[Termes IGN] semis (sylviculture)
[Termes IGN] sol forestier
[Vedettes matières IGN] ForesterieRésumé : (auteur) Natural regeneration of European beech (Fagus sylvatica) and Norway spruce (Picea abies) plays a crucial role in the future of many European mountain forests. It is affected by various soil and stand-related factors whose relative importance, especially in mixed stands, is still not known. In this study, we assessed the importance of stand composition, soil wetness, disturbances and different microsites and seedbeds for regeneration of beech and spruce in a mixed old-growth mountain forest. We also focused on how the effects of these factors change as regeneration gets older. We sampled all regeneration in 563 plots from different microsite types (deadwood, intact soil, treethrow pits and mounds), distinguishing three seedbeds (mosses, beech litter, bare substrate) for seedlings. We used soil survey and tree census data with generalized linear mixed models and variance partitioning to identify the main factors driving tree regeneration and their relative importance. Although beech was slightly less abundant in the canopy than spruce, it strongly outnumbered spruce in regeneration. Beech regeneration showed an affinity for beech litter-rich microsites and drier soils, while spruce was more common on deadwood and moister soils and its response to the seedbed was microsite-specific. The regeneration of both species was positively related to the proportion of their own species in the canopy, but more so in seedlings than in older regeneration cohorts, where soil wetness was more important. The overall pattern of tree regeneration thus resulted from a complex interplay between site conditions and their alterations by current and former generations of canopy trees through the creation of new microsites (deadwood, uprooting mounds) or litter production. Where beech regeneration is not suppressed by excess soil wetness, it is much more successful than spruce due to its shade tolerance and ability to be established in the beech litter that dominates the forest floor. On the other hand, spruce regeneration is mostly restricted to elevated microsites with lower litter accumulation, such as deadwood and treethrow mounds. Our results indicate that both species exhibit an ability to modify their environment in favor of their own regeneration, but under current conditions, beech is more successful than spruce and can be expected to increase its dominance in the future. Numéro de notice : A2022-022 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2021.119802 Date de publication en ligne : 04/11/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119802 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99214
in Forest ecology and management > vol 504 (January-15 2022) . - n° 119802[article]Variable selection for estimating individual tree height using genetic algorithm and random forest / Evandro Nunes Miranda in Forest ecology and management, vol 504 (January-15 2022)
[article]
Titre : Variable selection for estimating individual tree height using genetic algorithm and random forest Type de document : Article/Communication Auteurs : Evandro Nunes Miranda, Auteur ; Bruno Henrique Groenner Barbosa, Auteur ; Sergio Henrique Godinho Silva, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 119828 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] apprentissage automatique
[Termes IGN] Brésil
[Termes IGN] classification par algorithme génétique
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] hauteur des arbres
[Termes IGN] modélisation de la forêt
[Termes IGN] optimisation (mathématiques)
[Vedettes matières IGN] ForesterieRésumé : (auteur) Tree height is an important trait in forest science and is highly associated with the site quality from which the trees are measured. However, other factors, such as competition and species interaction, may yield better estimates for individual tree height when taken into account, but these variables have so far been challenging in model fitting. We propose a hybrid approach using genetic algorithms for variables selection and a machine learning algorithm (random forest) for fitting models of individual tree heights. We compare our proposed hybrid method with a mixed-effects model and random forest model using a dataset of 5,608 trees and 189 environmental variables (forest inventory-based variables, soil, topographic, climate, spectral, and geographic) from sites in southeastern Brazil. The tree height models were evaluated using the coefficient of determination, absolute bias, and root means square error (RMSE) based on the validation of dataset performance. The optimal set of variables of the proposed method include the ratio of diameter at breast height to quadratic mean diameter, distance independent competition index, dominant height, the soil silt and boron content. Our findings showed that the proposed hybrid method achieved an accuracy comparable with other methodologies in estimating the total height of the individual trees, and such a modelling approach could have broader applications in forestry and ecological science where a studied response trait has a large number of potential explanatory variables. Numéro de notice : A2022-021 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2021.119828 Date de publication en ligne : 06/11/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119828 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99216
in Forest ecology and management > vol 504 (January-15 2022) . - n° 119828[article]Gaining insight into the allometric scaling of trees by utilizing 3d reconstructed tree models - a SimpleForest study / Jan Hackenberg (2022)
Titre : Gaining insight into the allometric scaling of trees by utilizing 3d reconstructed tree models - a SimpleForest study Type de document : Article/Communication Auteurs : Jan Hackenberg , Auteur ; Mathias I. Disney, Auteur ; Jean-Daniel Bontemps , Auteur Editeur : BioRxiv Année de publication : 2022 Projets : 1-Pas de projet / Importance : 18 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] données allométriques
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] modèle de croissance végétale
[Termes IGN] modélisation de la forêt
[Termes IGN] volume en bois
[Vedettes matières IGN] ForesterieRésumé : (auteur) Forestry utilizes volume predictor functions utilizing as input the diameter at breast height. Some of those functions take the power form Y = a ∗ Xb. In fact this function is fundamental for the biology field of allometric scaling theories founded round about a century ago. The theory describes the relationships between organs/body parts and the complete body of organisms.
With digital methods we can generate 3d forest point clouds non destructively in short time frames. SimpleForest is one free available tool which generates fully automated ground and tree models from high resoluted forest plots. Generated topological ordered cylinder models are called commonly QSMs.
We use SimpleForest QSMs an build a function which estimates the total supported wood volume at any given point of the tree. As input we use the supported soft wood volume for those query points. Instead of measuring directly the soft wood volume we use as a proxy the number of supported twigs. We argue with the pipe model theory for the correctness of the proxy.
We can use the named relationship to also filter our QSMs made of an open data set of tree clouds. The filter corrects overestimated radii. And we compare the corrected QSM volume against the harvested reference data for 66 felled trees. We also found QSM data of TreeQSM, a competitive and broadly accepted QSM modeling tool. Our RMSE was less than 40% of the tree QSM RMSE. And for other error measures, the r2adj. and the CCC, the relative improvement looked even better with 27% and 21% respectively.
We consider this manuscript as highly impactful because of the magnitude of quality improvement we do. The relation between soft volume and total volume distributions seems to be really strong and tree data can easily also be used as example data for the generic field of allometric scaling.Numéro de notice : P2022-008 Affiliation des auteurs : LIF+Ext (2020- ) Thématique : FORET/MATHEMATIQUE Nature : Preprint nature-HAL : Préprint DOI : 10.1101/2022.05.05.490069 Date de publication en ligne : 05/05/2022 En ligne : https://doi.org/10.1101/2022.05.05.490069 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101945 Towards sustainable forestry: Using a spatial Bayesian belief network to quantify trade-offs among forest-related ecosystem services / Catherine Frizzle in Journal of Environmental Management, vol 301 ([01/01/2022])
[article]
Titre : Towards sustainable forestry: Using a spatial Bayesian belief network to quantify trade-offs among forest-related ecosystem services Type de document : Article/Communication Auteurs : Catherine Frizzle, Auteur ; Richard A. Fournier, Auteur ; Melanie Trudel, Auteur ; Joan E. Luther, Auteur Année de publication : 2022 Article en page(s) : n° 113817 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] gestion forestière durable
[Termes IGN] réseau bayesien
[Termes IGN] service écosystémique
[Termes IGN] théorie de Dempster-Shafer
[Vedettes matières IGN] ForesterieRésumé : (auteur) Assessing trade-offs among ecosystem services (ESs) that are provided by forests is necessary to support decision-making and to minimize negative effects of timber harvesting. In this study, we examined how spatial data, forest operational rules, ESs, and probabilistic statistics can be combined into a practical tool for trade-off analysis that could guide decision-making towards sustainable forestry. Our main goal was to analyze trade-offs among the wood provisioning ES and other forest ESs at the landscape level using a Bayesian belief network (BBN). We used LiDAR data to derive four ES layers as inputs to a spatial BBN: (i) wood provisioning; (ii) erosion regulating; (iii) climate regulating; and (iv) habitat supporting. We quantified operational constraints with four forest operational rules (FOR) that were defined in terms of: (i) potential harvest block size; (ii) distance between a small potential harvest block and a larger harvest block; (iii) gross merchantable volume (GMV); and (iv) distance to an existing resource road. Maps of the most probable trade-off classes between the wood provisioning ES and other ESs enabled us to identify areas where timber harvesting should be avoided or where timber harvesting should have a very low negative effect on other ESs. Even with our most restrictive management scenario, the total GMV that could be harvested met the annual allowable cut (AAC) volume required to meet sustainable forestry objectives. Through our study, we demonstrated that high-resolution spatial data could be used to quantify trade-offs among wood provisioning ES and other forest-related ESs and to simulate small changes in ES indicators within the BBN. We also demonstrated the potential to evaluate management scenarios to reduce trade-offs by considering FOR as inputs to the BBN. Maps of the most probable trade-off classes among two or three ESs under operational constraints provide key information to guide forest management decision-making towards sustainable forestry. Numéro de notice : A2022-338 Affiliation des auteurs : non IGN Thématique : FORET/MATHEMATIQUE Nature : Article DOI : 10.1016/j.jenvman.2021.113817 Date de publication en ligne : 01/10/2021 En ligne : https://doi.org/10.1016/j.jenvman.2021.113817 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100709
in Journal of Environmental Management > vol 301 [01/01/2022] . - n° 113817[article]Understory plant community responses to widespread spruce mortality in a subalpine forest / Trevor A. Carter in Journal of vegetation science, vol 33 n° 1 (January 2022)
[article]
Titre : Understory plant community responses to widespread spruce mortality in a subalpine forest Type de document : Article/Communication Auteurs : Trevor A. Carter, Auteur ; Paula J. Fornwalt, Auteur ; Katleen A. Dwire, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : 15 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies alba
[Termes IGN] forêt subalpine
[Termes IGN] insecte nuisible
[Termes IGN] Leaf Area Index
[Termes IGN] maladie phytosanitaire
[Termes IGN] mortalité
[Termes IGN] Picea abies
[Termes IGN] régression linéaire
[Termes IGN] semis (sylviculture)
[Termes IGN] sous-étage
[Termes IGN] Wyoming (Etats-Unis)
[Vedettes matières IGN] ForesterieRésumé : (auteur) Aims: Spruce beetles (Dendroctonus rufipennis) are causing widespread spruce (Picea spp.) mortality in subalpine forests in western North America. Spruce beetles are changing forest structure and composition by killing a dominant overstory species, but we know little about how the understory community responds to the increase in resource availability brought about by spruce mortality, what mechanisms drive its response, or how its response affects other forest properties and processes.
Location: Glacier Lakes Ecosystem Experiments Site, Medicine Bow Mountains, Wyoming, USA.
Methods: We measured understory community cover and richness in 75 permanent plots during and 10 years after an epidemic spruce beetle outbreak, and measured trait values for 46 common understory species. We used linear regression to determine how the understory community has changed over time and along a gradient of spruce mortality, and to evaluate the relative support for two mechanisms contributing to species responses.
Results: Understory cover nearly doubled between sampling periods and increased the most where spruce mortality was most severe. Understory richness doubled and showed a weak positive trend with spruce mortality. Understory species with the largest increases in cover were the most frequent across the landscape before the disturbance, were the tallest at maturity and had the lowest leaf turgor loss points. Fir seedling density decreased over time, with decreases lessening with increases in understory cover. Changes in spruce seedling density were not predicted by changes in understory cover.
Conclusions: Our findings highlight some of the diverse ways in which understory communities can be altered by spruce beetle outbreaks, and how the direction and magnitude of change can depend on the amount of spruce mortality as well as on priority effects and traits of pre-disturbance species. Our findings also highlight how understory community changes can have implications for other forest properties and processes, such as tree regeneration and forest recovery.Numéro de notice : A2022-173 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1111/jvs.13109 Date de publication en ligne : 14/12/2021 En ligne : https://doi.org/10.1111/jvs.13109 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99809
in Journal of vegetation science > vol 33 n° 1 (January 2022) . - 15 p.[article]Genetic diversity of seeds from four German Douglas fir (Pseudotsuga menziesii) seed orchards / Birte Pakull in European Journal of Forest Research, vol 140 n° 6 (December 2021)PermalinkPrescribed burning as a cost-effective way to address climate change and forest management in Mediterranean countries / Renata Martins Pacheco in Annals of Forest Science, vol 78 n° 4 (December 2021)PermalinkRadiative transfer modeling in structurally complex stands: towards a better understanding of parametrization / Frédéric André in Annals of Forest Science, vol 78 n° 4 (December 2021)PermalinkInflation of wood resources in European forests: The footprints of a big-bang / Jean-Daniel Bontemps in Plos one, vol 16 n° 11 (November 2021)PermalinkQuels besoins de connaissances pour le futur des forêts en France ? Au-delà du plan de relance / Maya Leroy in Revue forestière française, vol 73 n° 1 (2021)PermalinkThinning effect of C sequestration along an elevation gradient of mediterranean pinus spp. plantations / Antonio M. Cachinero-Vivar in Forests, vol 12 n° 11 (November 2021)PermalinkThe impact of air pollution on the growth of scots pine stands in poland on the basis of dendrochronological analyses / Longina Chojnacka-Ożga in Forests, vol 12 n° 10 (October 2021)PermalinkVariation in downed deadwood density, biomass, and moisture during decomposition in a natural temperate forest / Tomas Přívětivý in Forests, vol 12 n° 10 (October 2021)PermalinkAssessing the land expectation value of even-aged vs coppice-with-standards stand management and long-term effects of whole-tree harvesting on forest productivity and profitability / Abdelwahad Bessaad in Annals of Forest Science, vol 78 n° 3 (September 2021)PermalinkRelative influence of stand and site factors on aboveground live-tree carbon sequestration and mortality in managed and unmanaged forests / Christel C. Kern in Forest ecology and management, vol 493 (August-1 2021)PermalinkDynamique contrastée de la compaction d’un ferralsol après une défriche mécanisée alternative en Guyane française / Xavier Guerrini in Bois et forêts des tropiques, n° 348 ([01/07/2021])PermalinkThe presence of shade-intolerant conifers facilitates the regeneration of Quercus petraea in mixed stands / Jeremy Borderieux in Forest ecology and management, vol 491 (July-1 2021)PermalinkThe social drift of trees. Consequence for growth trend detection, stand dynamics, and silviculture / Hans Pretzsch in European Journal of Forest Research, vol 140 n° 3 (June 2021)PermalinkTowards silviculture guidelines to produce large-sized silver birch (betula pendula roth) logs in Western Europe / Héloïse Dubois in Forests, vol 12 n° 5 (May 2021)PermalinkChemical interaction between Quercus pubescens and its companion species is not emphasized under drought stress / H. Hashoum in European Journal of Forest Research, vol 140 n° 2 (April 2021)PermalinkFour-year-performance of oak and pine seedlings following mechanical site preparation with lightweight excavators / Noé Dumas in Silva fennica, vol 55 n° 2 (April 2021)PermalinkModels for integrating and identifying the effect of senescence on individual tree survival probability for Norway spruce / Jouni Siipilehto in Silva fennica, vol 55 n° 2 (April 2021)PermalinkKeeping mixtures of Norway spruce and birch in production forests: insights from survey data / Emma Hölmstrom in Scandinavian journal of forest research, vol 36 n° 2-3 ([01/03/2021])PermalinkThe Salem simulator version 2.0: a tool for predicting the productivity of pure and mixed stands and simulating management operations / Raphaël Aussenac in Open Research Europe, vol 2021 ([01/03/2021])PermalinkModelling potential density of natural regeneration of European oak species (Quercus robur L., Quercus petraea (Matt.) Liebl.) depending on the distance to the potential seed source: Methodological approach for modelling dispersal from inventory data at forest enterprise level / Maximilian Axer in Forest ecology and management, vol 482 ([15/02/2021])Permalink