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Analyse et consolidation des résultats sur les estimations de superficie du couvert forestier et de ses changements entre 2000 et 2016 en république du Congo / Suspense Averti Ifo in Revue Française de Photogrammétrie et de Télédétection, n° 223 (mars - décembre 2021)
Titre : Analyse et consolidation des résultats sur les estimations de superficie du couvert forestier et de ses changements entre 2000 et 2016 en république du Congo Type de document : Article/Communication Auteurs : Suspense Averti Ifo, Auteur ; Christophe Sannier, Auteur ; Gabriel Jaffrain, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 104 - 117 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] analyse diachronique
[Termes IGN] changement d'occupation du sol
[Termes IGN] Congo
[Termes IGN] couvert forestier
[Termes IGN] échantillonnage (statistique)
[Termes IGN] estimation statistique
[Termes IGN] Réduction des émissions dues à la déforestation et la dégradation des forêts, REDD
[Termes IGN] superficieRésumé : (Auteur) Des rapports précis et cohérents sur l'évolution de la superficie forestière et des changements d’occupation du sol sont importants dans le contexte de l’accord de Paris où les pays ont l’obligation de soumettre régulièrement leurs rapports sur le bilan émission absorption des gaz à effet de serre. Cette notification des changements peut avoir un impact direct sur les paiements par le biais de comparaisons avec les niveaux de référence (émissions) nationaux dans le cadre de la réduction des émissions dues à la déforestation et à la dégradation des forêts, notamment dans le cadre du processus REDD+. Cependant avant cela, les pays sont invités à renforcer leur système national de surveillance des forêts mais aussi de production des produits cartographiques qui respectent des règles robustes d’évaluation de l’incertitude des estimations de l’évolution de la superficie du couvert forestier prescrites par la CCNUCC. Dans cette étude, nous présentons les résultats de la précision des nombreuses cartes forestières dont le Congo dispose en utilisant l’approche assistée par modèle développée par Sannier et al, 2014, adaptée au contexte de la République du Congo. Les résultats de l’étude montrent une sous-estimation des près de 50% des pertes forestières dans la période entre 2000 et 2014 que ce soit par la méthode des estimations directes ou des estimations par régression. La comparaison des deux méthodes montre que les estimations des pertes de la couverture forestière par la méthode échantillons point sous-estime l’estimation des pertes sur la période 2000-2014 ainsi que sur la période 2014-2016. Nous concluons qu’il faut renforcer les équipes nationales en charge de l’élaboration des cartes forestières mais aussi que le pays doit s’approprier cette méthode de Sannier et al. 2014 pour l’évaluation de la précision. Numéro de notice : A2021-666 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueNat DOI : 10.52638/rfpt.2021.587 Date de publication en ligne : 25/08/2021 En ligne : https://doi.org/10.52638/rfpt.2021.587 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98763
in Revue Française de Photogrammétrie et de Télédétection > n° 223 (mars - décembre 2021) . - pp 104 - 117[article]
Titre : Analysing 18th century hydrographic data: a campaign in the Bay of Biscay, 1750-1751 Type de document : Article/Communication Auteurs : Helen Mair Rawsthorne Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2021 Conférence : Data for History 2021, 4th Data for History conference : Modelling Time, Places, Agents 19/05/2021 30/06/2021 Berlin virtuel Allemagne OA Abstracts only Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] campagne d'observations
[Termes IGN] carte ancienne
[Termes IGN] carte marine
[Termes IGN] données hydrographiques
[Termes IGN] sondage par points
[Termes IGN] Terre-Neuve, île de (Terre-Neuve-et-Labrador)
[Termes IGN] traitement de donnéesRésumé : (auteur) This paper features part of the work carried out for my Master’s thesis in Epistemology, History of Science and Technology. The project was completed during a six-month internship with the Région Nouvelle-Aquitaine as part of the Nouvelle-Aquitaine et Outre-Mers programme. In 2020, the French Service Hydrographique et Océanographique de la Marine (Shom) celebrated its 300th anniversary. The Shom is the French public authority for maritime and coastal geographical reference information. Such information is obtained through specific measurement techniques that have evolved throughout history. The Shom's predecessor, the Dépôt des Cartes et Plans de la Marine, was created in 1720 in order to collect, analyse and compile the documents produced by the maritime community to construct nautical maps. It was in the interest of the royal power of the time to collect mariners’ logbooks to monopolise the information contained inside them. They did this via the Grande Ordonnance de la Marine, established in 1681 and written by Colbert, secretary of the navy under the reign of Louis XIV, which required pilots of vessels to submit all logbooks to the Greffe de l’Amirauté. Then, in 1773 the Dépôt became the sole institution in charge of the production and publication of nautical charts in France. As well as simply collecting logbooks, the Dépôt began producing and enforcing rules and standards on how to log the information inside them. This information would then be regrouped by location and type, and used for the production or correction of nautical charts by Dépôt engineers. Upon discovering inaccuracies on nautical charts during voyages, mariners would often annotate the charts, which would later be subject to discussion and revision by the Dépôt upon their return. When significant errors or deficiencies were identified on published nautical charts, the Dépôt, along with the logistical assistance of the Ministre de la Marine, organised for hydrographic campaigns to be carried out to verify and improve existing nautical charts. In 1750 and 1751, a hydrographic campaign was conducted in the Bay of Biscay by a captain of the French Navy, chosen thanks to his practical navigation experience. The aim was to correct two charts of the region and to carry out landing soundings that could be added to new charts. During the mission, over 350 soundings were carried out in the Bay using a leadline to measure the depth of the water and to record samples of the seabed at different points. For every sounding point, some or all of the following information were recorded in manuscripts written on board the ship: the date, the time, the depth of the water, the nature of the seabed and the geographic position, either with bearings, with geographic coordinates or by dead reckoning. This study presents a methodology for the processing and analysis of the hydrographic data recorded during this campaign. The processing workflow involves numerous steps: the datafication of the information contained in the ship’s documents; the definition of the digitised data via the analysis of the accompanying historical archives of the campaign and the addition of metadata; the standardisation of the digitised data to comply with curent norms; the classification of the digitised data according to modern reference data. The newly interoperable historical data can then be compared and analysed alongside equivalent data collected at different moments in history that have undergone the same data processing. In this project, the historical data from the campaign, once processed, are compared to current data, collected and diffused by the Shom, allowing an analysis of the evolution and the continuities in the bathymetry and sedimentology in the Bay of Biscay. The methodology developed makes use of digital humanities tools, particularly digital cartography tools for visualising the mapping of the processed historical data. Numéro de notice : C2021-005 Affiliation des auteurs : UGE-LASTIG (2020- ) Thématique : GEOMATIQUE Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans En ligne : https://hal.science/hal-03239920v1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97795 
Titre : Towards a systematic and continuous monitoring of climate change impacts on forest productivity in Europe [diaporama] Type de document : Article/Communication Auteurs : Clémentine Ols Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2021 Conférence : DEEPSURF 2021, conference 12/10/2021 14/10/2021 Nancy France OA Abstracts only, European webinar 2022, From National Forest Inventories to European Level Forest Monitoring 27/01/2022 14/10/2021 Nancy France OA Abstracts only Importance : 35 p. Langues : Anglais (eng) Descripteur : [Termes IGN] Autriche
[Termes IGN] cerne
[Termes IGN] changement climatique
[Termes IGN] données de terrain
[Termes IGN] échantillonnage (statistique)
[Termes IGN] Europe (géographie politique)
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] modélisation de la forêt
[Termes IGN] productivité biologique
[Termes IGN] stratégie
[Termes IGN] surveillance forestière
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Climate change mitigation and energy transition are becoming priorities on many political agenda across the world, and especially in Europe. Forests, through their capacity to sequester carbon and produce renewable materials, are key assets to reach these environmental goals. European forests are encountered across wide biogeographic gradients and have recently shown contrasted productivity responses to climate change. Maximizing the climate benefits of European forests requires to precisely track forest productivity trajectories across regions in a continuously changing growing environment. National Forest Inventories (NFIs) perform systematic forest surveys across space and time and are powerful tools to monitor forest productivity dynamics and climate controls upon forest productivity at wide geographical scales. Building upon the ongoing pan-European harmonization of NFI data and information, we developed an original and promising modeling framework to extract large-scale climate-driven productivity dynamics and confront them to silvicultural and environmental attributes. With its simple and versatile design, it can be easily applied to diverse NFI schemes (annual vs. periodic field campaigns, permanent vs. temporary plots, radial increment vs. diameter measurements). To illustrate its promising potential to monitoring forest productivity dynamics, we consecutively applied it to study pure and even-aged conifer forests (1) in France over the 2006-2016 and (2) in France and Austria over the 1996-2016 period. Results highlighted in both cases a strong control of water resources on recent productivity trends, particularly in plains where fast-growing conifers species have been massively introduced during the XXe century and where sequestration dynamics have been the least favorable. Greater forest structural complexity was also identified as a driver of greater forest resilience to climate change. These results are of major concerns when conifer plantations have been largely encouraged these last decades, notably through state financial programs. Harmonized NFI data at the transnational level provide reliable information to i) survey carbon sequestration dynamics of different regional forest sinks; (ii) alert on the weakening of these sinks, (iii) implement large-scale climate-smart forest management; and (iv) adapt carbon sequestration strategies (ex. tree species substitution). The application of the present framework to other NFIs in Europe would support an integrative and continental monitoring of forest resources, in line with current EU strategies. Numéro de notice : C2021-033 Affiliation des auteurs : LIF+Ext (2020- ) Thématique : FORET Nature : Communication nature-HAL : ComSansActesPubliés-Unpublished DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99046 Documents numériques
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Titre : How do species and data characteristics affect species distribution models and when to use environmental filtering? Type de document : Article/Communication Auteurs : Lukáš Gábor, Auteur ; Vítězslav Moudrý, Auteur ; Vojtěch Barták, Auteur ; Vincent Lecours, Auteur Année de publication : 2020 Article en page(s) : pp 1567 - 1584 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] distribution spatiale
[Termes IGN] données environnementales
[Termes IGN] données localisées
[Termes IGN] échantillonnage (statistique)
[Termes IGN] entropie maximale
[Termes IGN] erreur d'échantillon
[Termes IGN] filtrage d'information
[Termes IGN] interaction spatialeRésumé : (auteur) Species distribution models (SDMs) are widely used in ecology and conservation. However, their performance is known to be affected by a variety of factors related to species occurrence characteristics. In this study, we used a virtual species approach to overcome the difficulties associated with testing of combined effects of those factors on performance of presence-only SDMs when using real data. We focused on the individual and combined roles of factors related to response variable (i.e. sample size, sampling bias, environmental filtering, species prevalence, and species response to environmental gradients). Results suggest that environmental filtering is not necessarily helpful and should not be performed blindly, without evidence of bias in species occurrences. The more gradual the species response to environmental gradients is, the greater is the model sensitivity to an inappropriate use of environmental filtering, although this sensitivity decreases with higher species prevalence. Results show that SDMs are affected to the greatest degree by the species response to environmental gradients, species prevalence, and sample size. Models’ accuracy decreased with sample size below 300 presences. Furthermore, a high level of interactions among individual factors was observed. Ignoring the combined effects of factors may lead to misleading outcomes and conclusions. Numéro de notice : A2020-414 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1615070 Date de publication en ligne : 14/05/2019 En ligne : https://doi.org/10.1080/13658816.2019.1615070 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95465
in International journal of geographical information science IJGIS > vol 34 n° 8 (August 2020) . - pp 1567 - 1584[article]
Titre : Modelling perceived risks to personal privacy from location disclosure on online social networks Type de document : Article/Communication Auteurs : Fatma S. Alrayes, Auteur ; A.I. Abdelmoty, Auteur ; B.A. El-Geresy, Auteur ; G. Theodorakopoulos, Auteur Année de publication : 2020 Article en page(s) : pp 150 - 176 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géomatique
[Termes IGN] accès aux données localisées
[Termes IGN] appariement sémantique
[Termes IGN] données issues des réseaux sociaux
[Termes IGN] échantillonnage (statistique)
[Termes IGN] géolocalisation
[Termes IGN] partage de données localisées
[Termes IGN] protection de la vie privée
[Termes IGN] réseau social
[Termes IGN] vulnérabilitéRésumé : (auteur) As users increasingly rely on online social networks for their communication activities, personal location data processing through such networks poses significant risks to users’ privacy. Location tracks can be mined with other shared information to extract rich personal profiles. To protect users’ privacy, online social networks face the challenge of ensuring transparent communication to users of how their data are processed, and explicitly obtaining users’ informed consent for the use of this data. In this paper, we explore the complex nature of the location disclosure problem and its risks to personal privacy. We evaluate, with an experiment involving 715 participants, the contributing factors to the perception of such risks with scenarios that mimic (a) realistic modes of interaction, where users are not fully aware of the extent of their location-related data being processed, and (b) with devised scenarios that deliberately inform users of the data they are sharing and its visibility to others. The results are used to represent the users’ perception of privacy risks when sharing their location information online and to derive a possible model of privacy risks associated with this sharing behaviour. Such a model can inform the design of privacy-aware online social networks to improve users’ trust and to ensure compliance with legal frameworks for personal privacy. Numéro de notice : A2020-009 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1654109 Date de publication en ligne : 22/08/2019 En ligne : https://doi.org/10.1080/13658816.2019.1654109 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94390
in International journal of geographical information science IJGIS > vol 34 n° 1 (January 2020) . - pp 150 - 176[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 079-2020011 RAB Revue Centre de documentation En réserve L003 Disponible PermalinkUtilisation d’un modèle numérique de hauteur en stratification des données de l’Inventaire Forestier National / Sophie Georges (2017)
PermalinkPermalinkPermalinkPermalinkApplications de la télédétection à l'observation de l'état sanitaire des forêts / G. Hildebrandt (1992)
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