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Early detection of pine wilt disease using deep learning algorithms and UAV-based multispectral imagery / Run Yu in Forest ecology and management, vol 497 (1 October 2021)
Titre : Early detection of pine wilt disease using deep learning algorithms and UAV-based multispectral imagery Type de document : Article/Communication Auteurs : Run Yu, Auteur ; Youqing Luo, Auteur ; Quan Zhou, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : n° 119493 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] apprentissage profond
[Termes IGN] Chine
[Termes IGN] classification par réseau neuronal convolutif
[Termes IGN] dépérissement
[Termes IGN] image captée par drone
[Termes IGN] image multibande
[Termes IGN] maladie phytosanitaire
[Termes IGN] milieu tropical
[Termes IGN] peuplement mélangé
[Termes IGN] Pinus (genre)
[Termes IGN] Pinus massoniana
[Termes IGN] réflectance spectrale
[Termes IGN] Ulmus (genre)
Résumé : (auteur) Pine wilt disease (PWD) is a global devastating threat to forest ecosystems. Therefore, a feasible and effective approach to precisely monitor PWD infection is indispensable, especially at the early stages. However, a precise definition of “early stage” and a rapid and high-efficiency method to detect PWD infection have not been well established. In this study, we systematically divided the PWD infection into green, early, middle, and late stages based on the needle color, the resin secretion, and whether the pine wood nematode (PWN) was carried. Simultaneously, an unmanned aerial vehicle (UAV) equipped with multispectral cameras was used to obtain images. Two target detection algorithms (Faster R-CNN and YOLOv4) and two traditional machine learning algorithms based on feature extraction (random forest and support vector machine) were employed to realize the recognition of infected pine trees. Moreover, we took into consideration of the influence of green broad-leaved trees on the identification of pine trees at the early stage of PWD infection. We obtained the following results: (1) the accuracy of Faster R-CNN (60.98–66.7%) was higher than that of YOLOv4 (57.07–63.55%), but YOLOv4 outperformed in terms of model size, processing speed, training time, and testing time; (2) although the traditional machine learning models had higher accuracy (73.28–79.64%), they were not able to directly identify the object from the images; (3) the accuracy of early detection of PWD infection showed an increase of 3.72–4.29%, from 42.36–44.59% to 46.08–48.88%, when broad-leaved trees were considered. In this study, the combination of UAV-based multispectral images and target detection algorithms allowed us to monitor the occurrence of PWD and obtain the distribution of infected trees at an early stage, which can provide technical support for the prevention and control of PWD. Numéro de notice : A2021-658 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2021.119493 En ligne : https://doi.org/10.1016/j.foreco.2021.119493 Format de la ressource électronique : URL article Permalink :
in Forest ecology and management > vol 497 (1 October 2021) . - n° 119493[article]Assessing 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 [en ligne], vol 78 n° 3 (September 2021)
Titre : Assessing 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 Type de document : Article/Communication Auteurs : Abdelwahad Bessaad, Auteur ; Jean-Philippe Terreaux, Auteur ; Nathalie Korboulewsky, Auteur Année de publication : 2021 Article en page(s) : n° 57 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Castanea sativa
[Termes IGN] changement climatique
[Termes IGN] croissance des arbres
[Termes IGN] gestion forestière durable
[Termes IGN] marché du bois
[Termes IGN] mortalité
[Termes IGN] productivité
[Termes IGN] Quercus sessiliflora
[Termes IGN] récolte de bois
[Vedettes matières IGN] Foresterie
Résumé : (auteur) Key message: Whole-tree harvesting makes forests more profitable than conventional harvest as long as the impact on tree growth remains under 2.3% for even-aged oak ( Quercus petraea (Matt.) Liebl.) and 3.4% for sweet chestnut ( Castanea sativa Mill.) coppice with oak standards. Coppice-with-standards may have potential to be more profitable than even-aged oak in case of 50% rise in fuelwood prices with 10% decrease in timber prices.
Context: Making the shift to renewable energy sources requires increasing biomass removal from the forest in a sustainable way. Today, the most common practice for forest biomass extraction is whole-tree harvesting rather than conventional harvest in which only stems are harvested or sometimes branches larger than 7 cm in diameter. However, intensive biomass harvesting can certainly increase economic profitability but it could affect long-term forest productivity because more nutrients are exported from sites.
Aims: We explored the land expectation value of even-aged oak (Quercus petraea (Matt.) Liebl.) and sweet chestnut (Castanea sativa Mill.) coppice with oak standards under different discount rates and wood prices scenarios, tree mortality triggered by climate variation as well as the effects of a decrease in forest productivity due to whole-tree harvesting on the land expectation value (LEV).
Methods: We modeled two plausible harvesting scenarios for both stands and assessed their LEV. We first analyzed the sensitivity of the valuation results to discount rate, wood prices changes, and increased tree mortality rates. Second, we compared conventional harvest to whole-tree harvesting in which removing the fine wood implies a decrease in tree growth over the long term (between 1 and 10%).
Results: In the current economic situation, the LEV of even-aged oak is higher than coppice-with-standards but this situation could be reversed in case of rising energy prices and lower timber prices in the future. The variation of the discount rate has a significant impact on the LEV but 3% seems to be adequate for European forests. A gradual increase in annual tree mortality rate of 0.6 and 0.9% along even-aged and CWS rotation, respectively, reduced the LEV by half, while increased mortality with constant rates along the rotations had more negative effect on the LEV than gradual increases: 0.4–0.5% increases in mortality rates reduced both LEV’s by half. Whole-tree harvesting is able to improve the LEV for both stands by 36 to 64% compared to conventional harvest; but this improvement of LEV only lasts as long as the impact on tree growth remains under 2.3 and 3.4%, respectively, for even-aged oak stand and coppice-with-standards.
Conclusion: Whole-tree harvesting system increases forest profitability as long as the sustainability guidelines for biomass harvesting are respected. With the increased demand for fuelwood, the coppice-with-standards regime may become financially attractive once again and fulfill a multitude of forest owner objectives with a wide range of additional options.
Numéro de notice : A2021-519 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-021-01071-2 date de publication en ligne : 21/06/2021 En ligne : https://doi.org/10.1007/s13595-021-01071-2 Format de la ressource électronique : URL article Permalink :
in Annals of Forest Science [en ligne] > vol 78 n° 3 (September 2021) . - n° 57[article]Geoglam, l'agriculture par satellite / Laurent Polidori in Géomètre, n° 2194 (septembre 2021)
Titre : Geoglam, l'agriculture par satellite Type de document : Article/Communication Auteurs : Laurent Polidori, Auteur Année de publication : 2021 Article en page(s) : pp 17 - 17 Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] blé (céréale)
[Termes IGN] carte d'occupation du sol
[Termes IGN] Glycine max
[Termes IGN] image à haute résolution
[Termes IGN] Leaf Area Index
[Termes IGN] maïs (céréale)
[Termes IGN] modèle dynamique
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] observation de la Terre
[Termes IGN] Oryza (genre)
[Termes IGN] série temporelle
[Termes IGN] surface cultivée
Résumé : (Auteur) Des satellites pour la sécurité alimentaire et la transparence du marché agricole Numéro de notice : A2021-579 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtSansCL DOI : sans date de publication en ligne : 13/09/2021 Permalink :
in Géomètre > n° 2194 (septembre 2021) . - pp 17 - 17[article]
Code-barres Cote Support Localisation Section Disponibilité 063-2021081 SL Revue Centre de documentation Revues en salle En circulation
Exclu du prêtClimate warming predispose sessile oak forests to drought-induced tree mortality regardless of management legacies / Any Mary Petritan in Forest ecology and management, vol 491 (1st July 2021)
Titre : Climate warming predispose sessile oak forests to drought-induced tree mortality regardless of management legacies Type de document : Article/Communication Auteurs : Any Mary Petritan, Auteur ; Ion Catalin Petritan, Auteur ; Andrea Hevia, Auteur ; Helge Walentowski, Auteur ; Olivier Bouriaud , Auteur ; Raul Sánchez-Salguero, Auteur Année de publication : 2021 Projets : 3-projet - voir note / Article en page(s) : n° 119097 Note générale : bibliographie
This work was supported by NEMKLIM project: Nemoral Forests under Climate Extremes (NEMKLIM Project, grant number 3517861300), financed by the German Federal Agency for Nature Conservation (Bundesamt für Naturschutz, BfN) and the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety, Germany and by project PN 19070506 financed by Romanian National Authority from Scientific Research and Innovation.
Langues : Anglais (eng) Descripteur : [Termes IGN] chênaie
[Termes IGN] croissance des arbres
[Termes IGN] Europe centrale
[Termes IGN] forêt tempérée
[Termes IGN] mortalité
[Termes IGN] précipitation
[Termes IGN] Quercus sessiliflora
[Termes IGN] Roumanie
[Termes IGN] sécheresse
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] température de l'air
[Termes IGN] vulnérabilité
[Vedettes matières IGN] Végétation et changement climatique
Résumé : (auteur) Climate warming-related drought could become a major driver of large-scale forest dieback. However, little is known about how past management legacies modulate the climate-growth responses during recent dieback episodes in central European oak forests. Here, we examine the role played by past management –unmanaged old-growth vs. managed forests– in recent tree mortality events occurring in Quercus petraea (Matt.) Liebl. stands across large areas of western Romania. We analyze how stand structure (tree size, competition) and climatic factors (drought, temperature and precipitation) drive tree radial growth patterns in neighboring standing dead and living trees. We analyzed basal area increments (BAI) trends, past management legacies and climate- and drought-growth relationships during the 20th century to distinguish the roles and interactions on recent warming-induced dieback. We observed that temperature rises and changes in atmospheric water demand during growing season let to increasing drought stress during the late 20th century affecting both managed and unmanaged forests. Dead trees from old-growth and managed forests showed lower growth than living trees after dieback onset. In both forests, dead and living trees displayed divergent growth patterns after dry 1980s, indicating that dieback was triggered by severe extreme conditions. Dead trees from managed stands experienced significant stronger growth reductions after 1980s though they experienced less tree-to-tree competition than dead trees in old-growth forest. High stand density negatively drove growth and enhanced climate sensitivity in old-growth stands. Competition acted synergistically with climate warming and drought causing tree mortality regardless of the management legacies in of Q. petraea forests. Our retrospective assessment of growth rates in relation with climate and structure changes offers valuable information for further forest conservation and management decisions of Q. petraea forests. These findings highlight the importance of past uses legacies driving recent forest dieback in temperate oak forests, making them more vulnerable under forecasted climate-warming related droughts in central Europe. Numéro de notice : A2021-496 Affiliation des auteurs : LIF+Ext (2020- ) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2021.119097 date de publication en ligne : 07/04/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119097 Format de la ressource électronique : URL article Permalink :
in Forest ecology and management > vol 491 (1st July 2021) . - n° 119097[article]The presence of shade-intolerant conifers facilitates the regeneration of Quercus petraea in mixed stands / Jeremy Borderieux in Forest ecology and management, vol 491 (1st July 2021)
Titre : The presence of shade-intolerant conifers facilitates the regeneration of Quercus petraea in mixed stands Type de document : Article/Communication Auteurs : Jeremy Borderieux, Auteur ; Yoan Paillet, Auteur ; Marine Dalmasso , Auteur ; Anders Mårell, Auteur ; Thomas Pérot, Auteur ; Patrick Vallet, Auteur Année de publication : 2021 Projets : 1-Pas de projet / Article en page(s) : n° 119189 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Cervidae
[Termes IGN] évapotranspiration
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] peuplement mélangé
[Termes IGN] Pinophyta
[Termes IGN] Quercus sessiliflora
[Termes IGN] régénération (sylviculture)
[Termes IGN] sol forestier
[Termes IGN] température de surface
[Vedettes matières IGN] Foresterie
Résumé : (auteur) Positive productivity-diversity relationships, pest-effect mitigation and increased resilience and stability maintain an ongoing interest for mixed stands in forestry. However, how mixing species affects forest regeneration is yet to be further explored.
We used data from the French National Forest Inventory (from 2006 to 2016) to model Quercus petraea (Matt.) Liebl regeneration cover in pure and mixed Quercus petraea stands; we included the effects of abiotic and biotic factors as well as mixture. We hypothesized that the characteristics of the companion species would prevent or facilitate the regeneration of oak.
Quercus petraea regeneration cover in this study responded negatively to total canopy cover and herbivory pressure. Mean July potential evapotranspiration (PET), mean December maximal temperature and soil pH are variables whose spatial variations over a given territory structure regeneration cover; all three of these variables have optimum values. Quercus petraea regeneration cover is linked to the proportion of Quercus petraea in the canopy layer in all mixed stands, except when the oak is mixed with shade-intolerant conifers: in this case, Quercus petraea regeneration is enhanced. The shade tolerance of admixed broadleaved species did not affect the Quercus petraea regeneration. This suggests that oak regeneration was facilitated with a shade-intolerant coniferous companion species due to better light transmittance through the crown or the competitive advantage of Quercus petraea over coniferous shade-intolerant species.
These results are of interest for oak mixtures since Quercus petraea regeneration cover benefits from mixtures with shade-intolerant conifers and is at least equal to that of pure stands.
Numéro de notice : A2021-309 Affiliation des auteurs : IGN+Ext (2020- ) Autre URL associée : vers HAL ouvert Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2021.119189 date de publication en ligne : 08/04/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119189 Format de la ressource électronique : URL article Permalink :
in Forest ecology and management > vol 491 (1st July 2021) . - n° 119189[article]Forest cover mapping and Pinus species classification using very high-resolution satellite images and random forest / Laura Alonso-Martinez in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, V-2-2021 (July 2021)PermalinkAn innovative and automated method for characterizing wood defects on trunk surfaces using high-density 3D terrestrial LiDAR data / Van-Tho Nguyen in Annals of Forest Science [en ligne], vol 78 n° 2 (June 2021)PermalinkDirect analysis in real-time (DART) time-of-flight mass spectrometry (TOFMS) of wood reveals distinct chemical signatures of two species of Afzelia / Peter Kitin in Annals of Forest Science [en ligne], vol 78 n° 2 (June 2021)PermalinkPredicting tree species based on the geometry and density of aerial laser scanning point cloud of treetops / Nina Kranjec in Geodetski vestnik, vol 65 n° 2 (June - August 2021)PermalinkProvisioning forest and conservation science with high-resolution maps of potential distribution of major European tree species under climate change / Debojyoti Chakraborty in Annals of Forest Science [en ligne], vol 78 n° 2 (June 2021)PermalinkUpdating of forest stand data by using recent digital photogrammetry in combination with older airborne laser scanning data / Niels Lindgren in Scandinavian journal of forest research, vol 36 n° 5 ([01/06/2021])PermalinkMixture effect on radial stem and shoot growth differs and varies with temperature / Maude Toïgo in Forest ecology and management, vol 488 (15 May 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])PermalinkSelf-thinning tree mortality models that account for vertical stand structure, species mixing and climate / D.I. Forrester in Forest ecology and management, Vol 487 ([01/05/2021])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)Permalink