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Landsat-based monitoring of southern pine beetle infestation severity and severity change in a temperate mixed forest / Ran Meng in Remote sensing of environment, vol 269 (February 2022)
[article]
Titre : Landsat-based monitoring of southern pine beetle infestation severity and severity change in a temperate mixed forest Type de document : Article/Communication Auteurs : Ran Meng, Auteur ; Renjie Gao, Auteur ; Feng Zhao, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 112847 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse spatiale
[Termes IGN] dépérissement
[Termes IGN] forêt tempérée
[Termes IGN] image Landsat-8
[Termes IGN] insecte nuisible
[Termes IGN] mortalité
[Termes IGN] peuplement mélangé
[Termes IGN] Scolytinae
[Termes IGN] signature spectrale
[Termes IGN] surveillance forestière
[Termes IGN] xylophageRésumé : (auteur) The recent northward expansion of Southern Pine Beetle (SPB) outbreaks associated with warming winters has caused extensive tree mortality in temperate pine forests, significantly affecting forest dynamics, structure, and functioning. Spatially-explicit early warning and detection of SPB-induced tree mortality is critical for timely and sustainable forest management practices. The unique contributions of remote sensing technologies to mapping the location, extent, and severity of beetle outbreaks, as well as assisting in analyzing the potential drivers for outbreak predictions, have been well recognized. However, little is known about the performance of moderate resolution satellite multispectral imagery for early warning and detection of SPB-induced tree mortality. Thus, we conducted this study, as the first attempt, to capture the spatial-temporal patterns of SPB infestation severity at the regional scale and to understand the underlying environmental drivers in a spatially-explicit manner. First, we explored the spectral signatures of SPB-killed trees based on 30-m plot measurements and Landsat-8 imagery. Then, to improve detection accuracy for areas with low-moderate SPB infestation severity, we added spectral-temporal anomaly information in the form of a linear trend of the spectral index trajectory to a previously developed approach. The best overall accuracy increased from 84.7% to 90.1% and the best Macro F1 value increased from 0.832 to 0.900. Next, we compared the performances of spectral indices in mapping SPB infestation severity (i.e., % red stage within the 30-m grid cell). The results showed that the combination of Normalized Difference Moisture Index and Tasseled Cap Greenness had the best performance for mapping SPB infestation severity (2016: R2 = 0.754; RSME = 15.7; 2017: R2 = 0.787; RSME = 12.4). Finally, we found that climatic and landscape variables can explain the detected patterns of SPB infestation from 2014 to 2017 in our study area (R2 = 0.751; RSME = 9.67), providing valuable insights on possible predictors for early warning of SPB infestation. Specifically, in our study area, winter dew point temperature was found to be one of the most important predictors, followed by SPB infestation locations in the previous year, canopy cover of host species, elevation, and slope. In the context of continued global warming, our study not only provides a novel framework for efficient, spatially-explicit, and quantitative measurements of forest damage induced by SPB infestation over large scales, but also uncovers opportunities to predict future SPB outbreaks and take precautions against it. Numéro de notice : A2022-096 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1016/j.rse.2021.112847 Date de publication en ligne : 15/12/2021 En ligne : https://doi.org/10.1016/j.rse.2021.112847 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99538
in Remote sensing of environment > vol 269 (February 2022) . - n° 112847[article]Drought stress and pests increase defoliation and mortality rates in vulnerable Abies pinsapo forests / Rafael M. Navarro-Cerrillo in Forest ecology and management, vol 504 (January-15 2022)
[article]
Titre : Drought stress and pests increase defoliation and mortality rates in vulnerable Abies pinsapo forests Type de document : Article/Communication Auteurs : Rafael M. Navarro-Cerrillo, Auteur ; Pablo González-Moreno, Auteur ; Francisco José Ruiz-Gómez, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 119824 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies pinsapo
[Termes IGN] Andalousie
[Termes IGN] défoliation
[Termes IGN] dépérissement
[Termes IGN] Fungi
[Termes IGN] insecte nuisible
[Termes IGN] maladie infectieuse
[Termes IGN] mortalité
[Termes IGN] sapinière
[Termes IGN] stress hydrique
[Vedettes matières IGN] ForesterieRésumé : (auteur) Forest ecosystems are increasingly exposed to the combined pressure of climate change and attacks by pests and pathogens. These stress factors can threaten already vulnerable species triggering dieback and rising defoliation and mortality rates. To characterize abiotic (drought, climate warmings) and biotic (pathogens) risks and their spatiotemporal patterns we quantified the recent loss of vitality for the endangered and relict Abies pinsapo forests from Andalusia, south-eastern Spain. Abies pinsapo is an iconic Mediterranean fir showing a high vulnerability to drought stress and also to several pests (Cryphalus numidicus) and root rot fungi (Armillaria mellea). We analyzed a monitoring network dataset of radial growth, defoliation and mortality from 2001 to 2017 including 1025 trees situated in three major mountain ranges (Sierra de Grazalema, Sierra de las Nieves, and Sierra Bermeja). We fitted several statistical models to determine the main drivers of changes in defoliation, a proxy of tree vigor, and mortality. Defoliation and mortality rates were much higher towards the East of the study area, mirroring the gradient from Atlantic to Mediterranean climatic conditions. In the most affected stands tree defoliation increased in response to a combination of long and severe droughts, with attacks by the beetle C. numidicus. Mortality rates increased in response to a higher defoliation rate, a lower relative radial-growth rate, long and severe droughts and a higher incidence of A. mellea. Our findings illustrate the value of monitoring networks recording changes in forest health to quantify and forecast future vulnerability of threatened tree species. Numéro de notice : A2022-020 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2021.119824 Date de publication en ligne : 17/11/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119824 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99217
in Forest ecology and management > vol 504 (January-15 2022) . - n° 119824[article]Détection des prairies de fauche et estimation des périodes de fauche par télédétection / Emma Seneschal (2022)
Titre : Détection des prairies de fauche et estimation des périodes de fauche par télédétection Type de document : Mémoire Auteurs : Emma Seneschal, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2022 Importance : 103 p. Format : 21 x 30 cm Note générale : bibliographie
Rapport de fin d'étude, cycle des Ingénieurs diplômés de l’ENSG 3ème année, Information Géographique, Analyse Spatiale et TélédétectionLangues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] apprentissage profond
[Termes IGN] Aves
[Termes IGN] Cantal (15)
[Termes IGN] cartographie thématique
[Termes IGN] classification dirigée
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] échantillonnage de données
[Termes IGN] habitat animal
[Termes IGN] image multibande
[Termes IGN] image Sentinel-MSI
[Termes IGN] image Sentinel-SAR
[Termes IGN] Jura (39)
[Termes IGN] Perceptron multicouche
[Termes IGN] prairie
[Termes IGN] régressionIndex. décimale : IGAST Mémoires du Master Information Géographique, Analyse Spatiale et Télédétection Résumé : (auteur) Ce travail s’inscrit dans le projet Parcelle qui vise à promouvoir le développement de la chaîne de traitement Iota2, développée par le CESBIO. Dans ce cadre-là, une collaboration s’est développée avec l’OFB qui a besoin de cartographier les prairies de fauche précoce dans le cadre de son «Observatoire National de l’Ecosystème Prairie de Fauche» (ONEPF). Le report des fauches est plébiscité depuis de nombreuses années face au déclin de l’avifaune prairiale. Des programmes agri-environnementaux incitent les agriculteurs à reporter les fenaisons jusqu’à mi-juillet. Les cartographies du suivi des prairies de fauche avec une récolte tardive constitueraient un outil de suivi des surfaces de l’habitat potentiellement favorable à la reproduction des oiseaux prairiaux en France. L’utilisation de la télédétection avec Iota2 permettrait une production annuelle plus rapide et moins coûteuse par rapport à des campagnes terrains et au processus actuel de production. Ce travail répond aux problématiques suivantes :
— Comment et avec quelle précision peut-on identifier et cartographier les prairies de fauche en France ?
— Est-il possible d’estimer la période de fauche et à quelle précision ?
Les séries temporelles denses, multi-spectrales et à haute résolution des satellites S1 & S2 ont été retenues pour l’étude des gestions des prairies (fauche, pâture et mixte). Les comportements des prairies selon leur mode de gestion ont été analysés grâce aux profils spectro-temporels des parcelles (bandes et indices spectraux issus de S2). Iota2 a été utilisé pour classifier avec Random Forest ou Deep Learning les prairies selon leur type de gestion. Plusieurs configurations ont été testées : calcul d’indices spectraux, ajout d’informations dérivées de MNT, augmentation de données, modification de l’architecture du réseau de neurones profonds, etc. Les cartographies prédictives des prairies de fauche ont été générées pour les années 2019 et 2021 respectivement sur les zones géographiques Jura-Mâconais et du Cantal. De meilleurs résultats ont été obtenus avec les échantillons d’apprentissage des sites du Jura et de Mâcon (F-score de 0.96 pour les parcelles de fauche). Les nouvelles fonctionnalités de Iota2 ont permis d’estimer la période de fauche par régression (avec un MultiLayerPerceptron). Les premiers résultats réalisés avec les séries temporelles S2 semblent prometteurs (R2 supérieurs à 0.5 et bonnes précisions). Ainsi, Iota2 est un outil performant qui permet la production rapide et qualitative de cartes de suivi des gestions prairiales en intégrant la télédétection. Iota2 pourrait être intégrée dans le processus de l’ONEPF.Note de contenu : Introduction
1- Avifaune et prairie
2- Prairies et télédétection
3- Données
4- Détection des prairies de fauche
5- Détection des périodes de fauche
ConclusionNuméro de notice : 24021 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Mémoire de fin d'études IT Organisme de stage : CESBIO Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101819 Documents numériques
en open access
Détection des prairies... - pdf auteur -Adobe Acrobat PDF Regeneration of spruce - fir - beech mixed forests under climate and ungulate pressure / Mithila Unkule (2022)
Titre : Regeneration of spruce - fir - beech mixed forests under climate and ungulate pressure Titre original : Régénération des forêts mixtes épicéa - sapin - hêtre sous la pression du climat et des ongulés Type de document : Thèse/HDR Auteurs : Mithila Unkule, Auteur ; Benoît Courbaud, Directeur de thèse ; Philippe Balandier, Directeur de thèse Editeur : Grenoble [France] : Université Grenoble Alpes Année de publication : 2022 Importance : pp 207 Format : 21 x 30 cm Note générale : bibliographie
Thèse pour obtenir le grade de Docteur de l'Université Grenoble Alpes, Spécialité Biodiversité, Ecologie, EnvironnementLangues : Anglais (eng) Descripteur : [Termes IGN] Abies alba
[Termes IGN] Alpes (France)
[Termes IGN] altitude
[Termes IGN] aménagement forestier
[Termes IGN] Cervidae
[Termes IGN] dynamique de la végétation
[Termes IGN] écologie forestière
[Termes IGN] Fagus sylvatica
[Termes IGN] forêt inéquienne
[Termes IGN] gestion forestière durable
[Termes IGN] jeune arbre
[Termes IGN] Jura, massif du
[Termes IGN] pente
[Termes IGN] Picea abies
[Termes IGN] régénération (sylviculture)
[Vedettes matières IGN] Végétation et changement climatiqueIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Global environmental changes are affecting tree population demography with potentially significant impacts on forest biodiversity and wood industry. Forest regeneration processes include seed production, growth and survival of saplings to the recruitment sizes at which trees are considered in forest inventories. Changes in regeneration dynamics directly affect forest composition and structure and can jeopardize the sustainability of forest management. This is especially the case in mountain forests where environmental gradients are strong and where forests are often uneven-aged, i.e. combining trees of all ages in a single stand. Regeneration processes are difficult to monitor. Large data sets often give only fixed pictures of sapling densities with little information on demographic processes. In this thesis, we quantified the effects of different biotic and abiotic factors on regeneration dynamics of Picea abies (spruce), Abies alba (fir) and Fagus sylvatica (beech) in the French Alps and Jura mountains. We also predicted changes in tree recruitment fluxes in these forests, for potential climate change situations. We recorded sapling height increment and density of spruce, fir and beech in 152 plots across the French Alps and Jura mountains. We then analysed how biotic and abiotic factors known to affect regeneration, namely altitude, slope, aspect, light availability, soil characteristics, ungulate browsing, temperature, precipitation and evapotranspiration, affected sapling density and growth using non-linear mixed models. We showed that temperature has a positive non-linear effect on sapling height growth and water resource availability has a positive effect on sapling density. Terminal shoot browsing, which prevents sapling height growth, is especially frequent on fir. In a second analysis, we built a more comprehensive model of regeneration dynamics, representing explicitly the process of new seedling production, sapling growth, browsing and survival, and finally their recruitment into adult trees. We predicted parameters for these processes in combination, using Approximate Bayesian Computation (ABC), based on the field data collected earlier. The results imply that more frequent and intense heat and drought events could negatively influence sapling growth and survival of the three species, with probable reduction of forest renewal fluxes. An increase of ungulate populations leading to increased browsing could be especially detrimental to fir and possibly also to beech saplings. We also predicted the potential tree recruitment fluxes for different IPCC climate projection scenarios for the year 2100, and showed that a reduction in tree recruitments is highly likely. This study shows that the ABC method can be efficiently used to estimate regeneration dynamic processes, based on sapling density, height increment and browsing data. It highlights the vulnerability of future forest regeneration to water availability and ungulate presence, urging researchers and forest managers alike to anticipate future potential important changes in mountain forest dynamics. Note de contenu : 1- Introduction
2- Theoretical framework
3- Spruce-fir-beech regeneration in French Alps
4- Estimating regeneration processes and tree recruitment rates
5- Discussion and perspectives
6- ConclusionsNuméro de notice : 15288 Affiliation des auteurs : non IGN Thématique : FORET Nature : Thèse française Note de thèse : Thèse de Doctorat : Biodiversité, Ecologie, Environnement : Grenoble : 2022 Organisme de stage : Laboratoire des EcoSystèmes et des Sociétés en Montagne DOI : sans En ligne : https://tel.hal.science/tel-03722811 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101511 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]Early detection of spruce vitality loss with hyperspectral data: Results of an experimental study in Bavaria, Germany / Kathrin Einzmann in Remote sensing of environment, vol 266 (December 2021)PermalinkUsing LiDAR and Random Forest to improve deer habitat models in a managed forest landscape / Colin S. Shanley in Forest ecology and management, vol 499 (November-1 2021)PermalinkUnsupervised denoising for satellite imagery using wavelet directional cycleGAN / Shaoyang Kong in IEEE Transactions on geoscience and remote sensing, vol 59 n° 8 (August 2021)PermalinkRole of maximum entropy and citizen science to study habitat suitability of jacobin cuckoo in different climate change scenarios / Priyinka Singh in ISPRS International journal of geo-information, vol 10 n° 7 (July 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)PermalinkTrajectory and image-based detection and identification of UAV / Yicheng Liu in The Visual Computer, vol 37 n° 7 (July 2021)PermalinkDiscovery of new colonies by Sentinel2 reveals good and bad news for emperor penguins / Peter T. Fretwell in Remote sensing in ecology and conservation, vol 7 n° 2 (June 2021)PermalinkCanopy openness and exclusion of wild ungulates act synergistically to improve oak natural regeneration / Julien Barrere in Forest ecology and management, Vol 487 ([01/05/2021])PermalinkStreams and rural abandonment are related to the summer activity of the invasive pest Drosophila suzukii in protected European forests / Alberto Maceda-Veiga in Forest ecology and management, vol 485 ([01/04/2021])PermalinkEarly detection of forest stress from European spruce bark beetle attack, and a new vegetation index: Normalized distance red & SWIR (NDRS) / Langning Huo in Remote sensing of environment, Vol 255 (March 2021)Permalink