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Nonparametric upscaling of bark beetle infestations and management from plot to landscape level by combining individual-based with Markov chain models / Bruno Walter Pietzsch in European Journal of Forest Research, vol 142 n° 1 (February 2023)
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Titre : Nonparametric upscaling of bark beetle infestations and management from plot to landscape level by combining individual-based with Markov chain models Type de document : Article/Communication Auteurs : Bruno Walter Pietzsch, Auteur ; Chris Wudel, Auteur ; Uta Berger, Auteur Année de publication : 2023 Article en page(s) : pp 129 - 144 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] chaîne de Markov
[Termes IGN] dépérissement
[Termes IGN] insecte nuisible
[Termes IGN] métamodèle
[Termes IGN] modèle de simulation
[Termes IGN] Picea abies
[Termes IGN] santé des forêts
[Termes IGN] Scolytinae
[Termes IGN] Suisse
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Linked to climate change, drivers such as increased temperatures and decreased water availability affect forest health in complex ways by simultaneously weakening tree vitality and promoting insect pest activity. One major beneficiary of climate-induced changes is the European spruce bark beetle (Ips typographus). To improve the mechanistic understanding of climate change impacts on long-term beetle infestation risks, individual-based simulation models (IBM) such as the bark beetle dispersion model IPS-SPREADS have been proven as effective tools. However, the computational costs of IBMs limit their spatial scale of application. While these tools are best suitable to simulate bark beetle dynamics on the plot level, upscaling the process to larger areas is challenging. The larger spatial scale is, nevertheless, often required to support the selection of adequate management intervention. Here, we introduce a novel two-step approach to address this challenge: (1) we use the IPS-SPREADS model to simulate the bark beetle dispersal at a local scale by dividing the research area into 250 × 250 m grid cells; and (2) we then apply a metamodel framework to upscale the results to the landscape level. The metamodel is based on Markov chains derived from the infestation probabilities of IPS-SPREADS results and extended by considering neighbor interaction and spruce dieback of each focal cell. We validated the metamodel by comparing its predictions with infestations observed in 2017 and 2018 in the Saxon Switzerland national park, Germany, and tested sanitation felling as a measure to prevent potential further outbreaks in the region. Validation showed an improvement in predictions by introducing the model extension of beetle spreading from one cell to another. The metamodel forecasts indicated an increase in the risk of infestation for adjacent forest areas. In case of a beetle mass outbreak, sanitation felling intensities of 80 percent and above seem to mitigate further outbreak progression. Numéro de notice : A2023-139 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s10342-022-01512-1 Date de publication en ligne : 29/10/2022 En ligne : https://doi.org/10.1007/s10342-022-01512-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102694
in European Journal of Forest Research > vol 142 n° 1 (February 2023) . - pp 129 - 144[article]Improving methods to predict aboveground biomass of Pinus sylvestris in urban forest using UFB model, LiDAR and digital hemispherical photography / Ihor Kozak in Urban Forestry & Urban Greening, vol 79 (January 2023)
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Titre : Improving methods to predict aboveground biomass of Pinus sylvestris in urban forest using UFB model, LiDAR and digital hemispherical photography Type de document : Article/Communication Auteurs : Ihor Kozak, Auteur ; Mikhail Popov, Auteur ; Igor Semko, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 127793 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] biomasse aérienne
[Termes IGN] détection d'arbres
[Termes IGN] données lidar
[Termes IGN] forêt urbaine
[Termes IGN] houppier
[Termes IGN] image hémisphérique
[Termes IGN] Leaf Area Index
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] modèle de régression
[Termes IGN] modèle numérique de terrain
[Termes IGN] photographie numérique
[Termes IGN] Pinus sylvestris
[Termes IGN] Pologne
[Termes IGN] semis de points
[Termes IGN] surface terrièreRésumé : (auteur) The article proposes methods for combining Airborne Laser Scanning (ALS) with Digital Hemispherical Photography (DHP) data required by the Urban Forest Biomass (UFB) model to predict the aboveground biomass (AGB) of Scotch pine (Pinus sylvestris L.) in urban forests of Lublin (Poland). The article also demonstrates the potential of ALS and DHP data in urban AGB estimation. ALS and Leaf Area Index (LAI) data were calculated using a voxels-vector approach based on the measurements taken at eight permanent sample plots (PSPs). The research was conducted in 2014 and the prediction was made until 2030. It was found that the determination coefficients (R2) for the Basal Area (BA) of the trees are 0.97, and the BA modeling parameters have a high correlation with those observed in the field (model efficiency (ME) 0.94). 83 % growth trajectory based on the measured BA was appropriately modeled using the UFB model (P > 0.9). The results for AGB show that the degree of fitting and accuracy are greatest for the Monte Carlo (MC) simulation technique based on ALS and DHP data (UBF with ALS and DHP) where R2 = 0.98, RMSE = 2.97 t/ha, MAE = 2.35 t/ha, rRMSE = 1.28 %, which performed better than MC simulation technique without ALS and DHP (UBF without ALS and DHP) where R2 = 0.94, RMSE = 4.58 t/ha, MAE = 3.64 t/ha, rRMSE = 3.29 %. The results indicate that the proposed method based on combining the UFB model, LiDAR and DHP allows us to improve the accuracy of the AGB prediction. Numéro de notice : A2023-023 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1016/j.ufug.2022.127793 Date de publication en ligne : 23/11/2022 En ligne : https://doi.org/10.1016/j.ufug.2022.127793 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102246
in Urban Forestry & Urban Greening > vol 79 (January 2023) . - n° 127793[article]Urban infrastructure expansion and artificial light pollution degrade coastal ecosystems, increasing natural-to-urban structural connectivity / Moisés A. Aguilera in Landscape and Urban Planning, vol 229 (January 2023)
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Titre : Urban infrastructure expansion and artificial light pollution degrade coastal ecosystems, increasing natural-to-urban structural connectivity Type de document : Article/Communication Auteurs : Moisés A. Aguilera, Auteur ; Maria Gracia González, Auteur Année de publication : 2023 Article en page(s) : n° 104609 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] ArcGIS
[Termes IGN] Chili
[Termes IGN] croissance urbaine
[Termes IGN] dégradation de l'environnement
[Termes IGN] écosystème
[Termes IGN] étalement urbain
[Termes IGN] habitat (nature)
[Termes IGN] intensité lumineuse
[Termes IGN] littoral
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] paysage urbain
[Termes IGN] pollution lumineuse
[Termes IGN] urbanismeRésumé : (auteur) Urbanization is provoking habitat loss and fragmentation, driving rapid landscape transformation worldwide. Remnant habitats in urban areas can be especially prone to degradation by human activities at short time scales, and poor planning during urban expansion can erode their structural and functional connectivity. Foredunes in particular are threatened significantly by human activities, including coastal urban infrastructure expansion, by bulldozing them and/or by interrupting their continuity across the shoreline, and also by associated light pollution. However, there is still scarce quantification about how urban processes determine changes in remnant habitat extent and modify the configuration of structural connectivity in coastal urban settings. Using an expanding conurbation located in north-central Chile (∼29°S) as model system, we investigated the rate of coastal foredune loss and spatial fragmentation due to urban expansion, and the change in the type of structural connectivity, i.e. with other natural habitats vs with urban infrastructure. Based on map analyses of structural connectivity among habitats and with urban infrastructure through time, we estimated foredune habitat extent and fragmentation and their shared border with other habitats and built infrastructure during two time intervals, 2010–2015 and 2015–2020. Distribution and intensity of light pollution on present foredunes were also quantified in situ through field sampling. We found 36 % decline in foredune area and increase in their connection with urban infrastructure. Urban wetlands and parallel dunes also experienced persistent area loss and increase in connection with urban infrastructure. Light pollution was intense in the foredune-beach ecotone. Given the rapid erosion of functional and structural connectivity of natural habitats, it becomes imperious to halt the reduction of remnant habitats and ecotones, and improve natural corridors in urban settings. Numéro de notice : A2023-127 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/GEOMATIQUE/URBANISME Nature : Article DOI : 10.1016/j.landurbplan.2022.104609 Date de publication en ligne : 17/10/2022 En ligne : https://doi.org/10.1016/j.landurbplan.2022.104609 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102507
in Landscape and Urban Planning > vol 229 (January 2023) . - n° 104609[article]A data-driven framework to manage uncertainty due to limited transferability in urban growth models / Jingyan Yu in Computers, Environment and Urban Systems, vol 98 (December 2022)
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Titre : A data-driven framework to manage uncertainty due to limited transferability in urban growth models Type de document : Article/Communication Auteurs : Jingyan Yu, Auteur ; Alex Hagen-Zanker, Auteur ; Naratip Santitissadeekorn, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 101892 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse de groupement
[Termes IGN] automate cellulaire
[Termes IGN] changement d'utilisation du sol
[Termes IGN] croissance urbaine
[Termes IGN] estimation bayesienne
[Termes IGN] étalement urbain
[Termes IGN] Europe (géographie politique)
[Termes IGN] méthode de Monte-Carlo par chaînes de Markov
[Termes IGN] modèle stochastique
[Termes IGN] simulation dynamiqueRésumé : (auteur) The processes of urban growth vary in space and time. There is a lack of model transferability, which means that models estimated for a particular study area and period are not necessarily applicable for other periods and areas. This problem is often addressed through scenario analysis, where scenarios reflect different plausible model realisations based typically on expert consultation. This study proposes a novel framework for data-driven scenario development which, consists of three components - (i) multi-area, multi-period calibration, (ii) growth mode clustering, and (iii) cross-application. The framework finds clusters of parameters, referred to as growth modes: within the clusters, parameters represent similar spatial development trajectories; between the clusters, parameters represent substantially different spatial development trajectories. The framework is tested with a stochastic dynamic urban growth model across European functional urban areas over multiple time periods, estimated using a Bayesian method on an open global urban settlement dataset covering the period 1975–2014.
The results confirm a lack of transferability, with reduced confidence in the model over the validation period, compared to the calibration period. Over the calibration period the probability that parameters estimated specifically for an area outperforms those for other areas is 96%. However, over an independent validation period, this probability drops to 72%. Four growth modes are identified along a gradient from compact to dispersed spatial developments. For most training areas, spatial development in the later period is better characterized by one of the four modes than their own historical parameters. The results provide strong support for using identified parameter clusters as a tool for data-driven and quantitative scenario development, to reflect part of the uncertainty of future spatial development trajectories.Numéro de notice : A2022-799 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article DOI : 10.1016/j.compenvurbsys.2022.101892 Date de publication en ligne : 08/10/2022 En ligne : https://doi.org/10.1016/j.compenvurbsys.2022.101892 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101966
in Computers, Environment and Urban Systems > vol 98 (December 2022) . - n° 101892[article]Multi-frequency simulation of ionospheric scintillation using a phase-screen model / Fernando D. Nunes in Navigation : journal of the Institute of navigation, vol 69 n° 4 (Fall 2022)
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Titre : Multi-frequency simulation of ionospheric scintillation using a phase-screen model Type de document : Article/Communication Auteurs : Fernando D. Nunes, Auteur ; Fernando M.G. Sousa, Auteur ; José M.V. Marçal, Auteur Année de publication : 2022 Article en page(s) : n° 545 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] amplitude
[Termes IGN] correction ionosphérique
[Termes IGN] fréquence multiple
[Termes IGN] ionosphère
[Termes IGN] méthode de Monte-Carlo
[Termes IGN] phase
[Termes IGN] scintillation
[Termes IGN] série temporelle
[Termes IGN] signal GNSS
[Termes IGN] teneur totale en électronsRésumé : (auteur) A fast Monte Carlo technique to simulate equatorial ionospheric scintillation on global navigation satellite system signals is proposed. The algorithm uses a single-layer phase-screen model of the ionosphere and the scintillation is expressed as a Huygens-Fresnel integral (HFI). By assuming a specially-tailored random phase screen, the HFI can be expressed in closed form as a combination of Fresnel integrals. We statistically characterize the amplitude and phase computed by the HFI for different values of the scintillation index S4. Results for the L1, L2, and L5 bands were obtained and compared with real data, showing good agreement. Some of the advantages of the proposed technique are: (a) the amplitude and phase of the scintillation process are simultaneously obtained; (b) arbitrarily long ionospheric scintillation time series with pre-defined stationary characteristics are synthesized; and (c) several scintillation time series corresponding to different carrier frequencies are generated using a common phase-screen model. Numéro de notice : A2022-918 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.33012/navi.545 Date de publication en ligne : 18/06/2022 En ligne : https://doi.org/10.33012/navi.545 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102446
in Navigation : journal of the Institute of navigation > vol 69 n° 4 (Fall 2022) . - n° 545[article]Modelling the future vulnerability of urban green space for priority-based management and green prosperity strategy planning in Kolkata, India: a PSR-based analysis using AHP-FCE and ANN-Markov model / Santanu Dinda in Geocarto international, vol 37 n° 22 ([10/10/2022])
PermalinkAn estimation method to reduce complete and partial nonresponse bias in forest inventory / James A. Westfall in European Journal of Forest Research, vol 141 n° 5 (October 2022)
PermalinkSimulation of land use/land cover changes and urban expansion in Estonia by a hybrid ANN-CA-MCA model and utilizing spectral-textural indices / Najmeh Mozaffaree Pour in Environmental Monitoring and Assessment, vol 194 n° 9 (September 2022)
PermalinkGenerating impact maps from bomb craters automatically detected in aerial wartime images using marked point processes / Christian Kruse in ISPRS Open Journal of Photogrammetry and Remote Sensing, vol 5 (August 2022)
PermalinkDART-Lux: An unbiased and rapid Monte Carlo radiative transfer method for simulating remote sensing images / Yingjie Wang in Remote sensing of environment, vol 274 (June 2022)
PermalinkExploring the spatial disparity of home-dwelling time patterns in the USA during the COVID-19 pandemic via Bayesian inference / Xiao Huang in Transactions in GIS, vol 26 n° 4 (June 2022)
PermalinkImpacts of spatiotemporal resolution and tiling on SLEUTH model calibration and forecasting for urban areas with unregulated growth patterns / Damilola Eyelade in International journal of geographical information science IJGIS, vol 36 n° 5 (May 2022)
PermalinkCoastal observation of sea surface tide and wave height using opportunity signal from Beidou GEO satellites: analysis and evaluation / Feng Wang in Journal of geodesy, vol 96 n° 4 (April 2022)
PermalinkUnderstanding the movement predictability of international travelers using a nationwide mobile phone dataset collected in South Korea / Yang Xu in Computers, Environment and Urban Systems, vol 92 (March 2022)
PermalinkAn integrated framework of global sensitivity analysis and calibration for spatially explicit agent-based models / Jeon-Young Kang in Transactions in GIS, vol 26 n° 1 (February 2022)
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