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In situ C-band data for wheat physiological functioning monitoring in the South Mediterranean region / Nadia Ouaadi (2022)
Titre : In situ C-band data for wheat physiological functioning monitoring in the South Mediterranean region Type de document : Article/Communication Auteurs : Nadia Ouaadi, Auteur ; Ludovic Villard, Auteur ; Saïd Khabba, Auteur ; Pierre-Louis Frison , Auteur ; Jamal Ezzahar, Auteur ; Mohamed Kasbani, Auteur ; Adnane Chakir , Auteur ; Pascal Fanise, Auteur ; Valérie Le Dantec, Auteur ; Mehrez Zribi, Auteur ; Salah Er-Raki, Auteur ; Lionel Jarlan, Auteur Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 2022 Projets : 2-Pas d'info accessible - article non ouvert / Conférence : IGARSS 2022, IEEE International Geoscience And Remote Sensing Symposium 17/07/2022 22/07/2022 Kuala Lumpur Malaysie Proceedings IEEE Importance : pp 4951 - 4954 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] bande C
[Termes IGN] blé (céréale)
[Termes IGN] coefficient de rétrodiffusion
[Termes IGN] cohérence photométrique
[Termes IGN] variation diurneRésumé : (auteur) Irrigated agriculture is the largest consumer of freshwater in the world, particularly in the South Mediterranean region that is already suffering from water shortages. Monitoring the water stress status of plants can contribute to an optimal use of irrigation. C-band radar data have shown great potential for monitoring soil and vegetation hydric conditions. While a diurnal cycle up to 1 dB has been observed over tropical forests, the behavior of annual crops is yet to be investigated. In this context, an experiment composed of a radar setup with 6 C-band antennas was installed in Morocco over a wheat field. 15 minutes full polarization acquisitions of the backscattering coefficient and the interferometric coherence are analyzed in relation with the physiological functioning of wheat. In this paper, the first results from the analysis of data collected during the 2020 growing season are presented. The results reveal the existence of a diurnal cycle of the interferometric coherence and the backscattering coefficient (up to 0.45 and 1.5 dB, respectively) with amplitudes increase in relation with vegetation development. Numéro de notice : C2022-041 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/IGARSS46834.2022.9884289 Date de publication en ligne : 28/09/2022 En ligne : https://doi.org/10.1109/IGARSS46834.2022.9884289 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101769 Monitoring leaf phenology in moist tropical forests by applying a superpixel-based deep learning method to time-series images of tree canopies / Guangqin Song in ISPRS Journal of photogrammetry and remote sensing, vol 183 (January 2022)
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Titre : Monitoring leaf phenology in moist tropical forests by applying a superpixel-based deep learning method to time-series images of tree canopies Type de document : Article/Communication Auteurs : Guangqin Song, Auteur ; Shengbiao Wu, Auteur ; Calvin K.F. Lee, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : pp 19 - 33 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] algorithme SLIC
[Termes IGN] apprentissage profond
[Termes IGN] canopée
[Termes IGN] classification dirigée
[Termes IGN] diagnostic foliaire
[Termes IGN] Enhanced vegetation index
[Termes IGN] feuille (végétation)
[Termes IGN] forêt tropicale
[Termes IGN] Panama
[Termes IGN] phénologie
[Termes IGN] photosynthèse
[Termes IGN] segmentation sémantique
[Termes IGN] série temporelle
[Termes IGN] superpixel
[Termes IGN] variation saisonnièreRésumé : (auteur) Tropical leaf phenology—particularly its variability at the tree-crown scale—dominates the seasonality of carbon and water fluxes. However, given enormous species diversity, accurate means of monitoring leaf phenology in tropical forests is still lacking. Time series of the Green Chromatic Coordinate (GCC) metric derived from tower-based red–greenblue (RGB) phenocams have been widely used to monitor leaf phenology in temperate forests, but its application in the tropics remains problematic. To improve monitoring of tropical phenology, we explored the use of a deep learning model (i.e. superpixel-based Residual Networks 50, SP-ResNet50) to automatically differentiate leaves from non-leaves in phenocam images and to derive leaf fraction at the tree-crown scale. To evaluate our model, we used a year of data from six phenocams in two contrasting forests in Panama. We first built a comprehensive library of leaf and non-leaf pixels across various acquisition times, exposure conditions and specific phenocams. We then divided this library into training and testing components. We evaluated the model at three levels: 1) superpixel level with a testing set, 2) crown level by comparing the model-derived leaf fractions with those derived using image-specific supervised classification, and 3) temporally using all daily images to assess the diurnal stability of the model-derived leaf fraction. Finally, we compared the model-derived leaf fraction phenology with leaf phenology derived from GCC. Our results show that: 1) the SP-ResNet50 model accurately differentiates leaves from non-leaves (overall accuracy of 93%) and is robust across all three levels of evaluations; 2) the model accurately quantifies leaf fraction phenology across tree-crowns and forest ecosystems; and 3) the combined use of leaf fraction and GCC helps infer the timing of leaf emergence, maturation and senescence, critical information for modeling photosynthetic seasonality of tropical forests. Collectively, this study offers an improved means for automated tropical phenology monitoring using phenocams. Numéro de notice : A2022-009 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2021.10.023 Date de publication en ligne : 10/11/2021 En ligne : https://doi.org/10.1016/j.isprsjprs.2021.10.023 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99057
in ISPRS Journal of photogrammetry and remote sensing > vol 183 (January 2022) . - pp 19 - 33[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2022011 SL Revue Centre de documentation Revues en salle Disponible 081-2022013 DEP-RECP Revue LASTIG Dépôt en unité Exclu du prêt 081-2022012 DEP-RECF Revue Nancy Dépôt en unité Exclu du prêt Simulation of the meltwater under different climate change scenarios in a poorly gauged snow and glacier-fed Chitral River catchment (Hindukush region) / Huma Hayat in Geocarto international, vol 37 n° 1 ([01/01/2022])
[article]
Titre : Simulation of the meltwater under different climate change scenarios in a poorly gauged snow and glacier-fed Chitral River catchment (Hindukush region) Type de document : Article/Communication Auteurs : Huma Hayat, Auteur ; Adnan Ahmad Tahir, Auteur ; sara Wajid, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : pp 103 - 119 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bassin hydrographique
[Termes IGN] changement climatique
[Termes IGN] données météorologiques
[Termes IGN] eau de fonte
[Termes IGN] estimation statistique
[Termes IGN] fonte des glaces
[Termes IGN] image Terra-MODIS
[Termes IGN] inondation
[Termes IGN] modèle de simulation
[Termes IGN] modèle numérique de surface
[Termes IGN] Pakistan
[Termes IGN] prévention des risques
[Termes IGN] ressources en eau
[Termes IGN] ruissellement
[Termes IGN] série temporelle
[Termes IGN] variation saisonnièreRésumé : (auteur) Seasonal and annual water supplies of the rivers originating in the Hindukush-Karakoram-Himalaya (HKH) region of Pakistan are important to manage the Indus basin irrigation system for better agricultural production and its dependent agrarian economy. In this study, we simulated the current and future snowmelt runoff in a poorly gauged river basin of the Hindukush region under Representative Concentration Pathways (RCP) climate change scenarios. Snowmelt Runoff Model (SRM) furnished with satellite snow cover maps and hydro-meteorological data were used to simulate the daily river discharge for the period 2000‒2005. The results indicated that SRM has effectually simulated the runoff in Chitral River with Nash-Sutcliffe model efficiency coefficient of 0.85 (0.84) and 0.88 (0.83) in the basin-wide (zone-wise) application during the calibration and validation periods, respectively. The results obtained under future climate change scenario showed ∼14‒19% increase in mean summer discharge under three mid-21st century RCP (2.6, 4.5 and 8.5) scenarios. While an increase of ∼13‒37% is expected under late-21st century RCP scenarios. This study can help water resource managers to plan and manage peak discharges from the Chitral River Basin in the future and can thus prevent major losses due to floods in the area. Numéro de notice : A2022-047 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2019.1700557 Date de publication en ligne : 12/12/2019 En ligne : https://doi.org/10.1080/10106049.2019.1700557 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99421
in Geocarto international > vol 37 n° 1 [01/01/2022] . - pp 103 - 119[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 059-2022011 RAB Revue Centre de documentation En réserve L003 Disponible A square-grid sampling support to reconcile systematicity and adaptivity in the periodic spatial survey of natural resources / Olivier Bouriaud (2022)
Titre : A square-grid sampling support to reconcile systematicity and adaptivity in the periodic spatial survey of natural resources Type de document : Article/Communication Auteurs : Olivier Bouriaud , Auteur ; François Morneau , Auteur ; Jean-Daniel Bontemps , Auteur Editeur : Research Square Année de publication : 2022 Projets : ARBRE / AgroParisTech (2007 -) Présentation : 24 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] échantillonnage
[Termes IGN] grille d'échantillonnage
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] placette d'échantillonnage
[Termes IGN] population
[Termes IGN] surveillance forestière
[Termes IGN] variation temporelle
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Spatially balanced sampling is the most efficient design for surveying continuous or spatial populations across space. The spatial sampling of large-scale surveys is mostly based on grids, whose properties drive, and potentially limit, the possibilities of building flexible samples. Conciliating spatial balance and flexibility remains difficult. In particular, periodicity causes high constraints to the sampling particularly when an increase in the frequency of the information delivery is sought. Sampling stratification of adaptive sampling intensity also conflicts the grid-based approach. We show that square grids have geometric homothetic properties that enable to answer these needs by supporting nested hierarchical subgrid sets. These properties can be exploited to cope with both spatial flexibility in the sampling effort and spatio-temporal coordination of samples. Whereas some surveys seemingly do exploit these properties practically across the world, no formal development has been made available in the survey sampling literature across fields of applications. Here we therefore define and demonstrate these properties, and show how they can be used to produce nested hierarchical grids compatible with multiple periodicity values of interest to natural monitoring, and with adapting sampling intensity across space and time. We also provide an original extension of this framework, intended to tune the sampling effort gradually while preserving spatial systematicity. We use the French National Forest Inventory survey to illustrate these properties and their use in a large-scale repeated inventory. We show the flexibility and diversity of sampling schemes that can be initiated with square grids and the limits of their use. Numéro de notice : P2022-004 Affiliation des auteurs : LIF (2020- ) Thématique : FORET/MATHEMATIQUE Nature : Article nature-HAL : Préprint DOI : 10.21203/rs.3.rs-1745991/v1 Date de publication en ligne : 08/07/2022 En ligne : https://doi.org/10.21203/rs.3.rs-1745991/v1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101265
Titre : Variations de volume des lacs pour l'analyse climatique : Améliorer la connaissance de la quantité d’eau des lacs et leur variation à partir de données satellitaires Type de document : Mémoire Auteurs : Iris Lucas, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2022 Importance : 67 p. Format : 21 x 30 cm Note générale : bibliographie
Rapport de fin d'étude, cycle des Ingénieurs diplômés de l’ENSG 3ème année, Spécialité PPMDLangues : Français (fre) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] bassin hydrographique
[Termes IGN] Canada
[Termes IGN] carte hypsométrique
[Termes IGN] Champagne (province, comté)
[Termes IGN] données altimétriques
[Termes IGN] extraction de traits caractéristiques
[Termes IGN] image Landsat-8
[Termes IGN] image radar moirée
[Termes IGN] image Sentinel-MSI
[Termes IGN] lac
[Termes IGN] méthode robuste
[Termes IGN] modèle de Gauss-Helmert
[Termes IGN] Ransac (algorithme)
[Termes IGN] régression
[Termes IGN] variation temporelle
[Termes IGN] volume d'eauIndex. décimale : MPPMD Mémoires du mastère spécialisé Photogrammétrie, Positionnement et Mesures de Déformation Résumé : (auteur) La ressource en eau douce est limitée, son étude fait partie des axes majeurs des études environnementales. C’est au sein de la cellule hydrologie continentale de CLS, pour le compte d’Apside que je me suis penchée sur cette question, appliquant les savoirs acquis en géomatique durant mes années à l’ENSG. L’objectif de ce stage est d’améliorer la connaissance de la quantité d’eau des lacs et leur variation à partir de données satellitaires. Ce savoir pourra être appliqué dans divers projets sur l’étude des lacs à CLS. Etudier les variations de volume nécessite l’utilisation de surfaces d’eau que l’on peut extraire par imagerie satellitaire (Sentinel-2, Landsat-8) et hauteurs d’eau provenant de satellites altimétriques (accessibles sur la plateforme Hydroweb). Pour ce faire, j’ai développé un algorithme d’extraction de surfaces d’eau par télédétection optique, puis développé une méthode d’estimation robuste pour dégager une courbe hypsométrique. Grâce à cette courbe, j’ai pu déterminer des variations de volumes pour divers bassins. Ce rapport détaille le processus développé, la méthodologie suivie et les éventuelles pistes d’amélioration possibles. Note de contenu :
1- Introduction
2- Extraire les données de surfaces d’eau
3- Extraire le profil des lacs : la courbe hypsométrique
4- Dernière étape de la chaine : génération des variations de volume
5- ConclusionNuméro de notice : 24053 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Mémoire de fin d'études IT Organisme de stage : Apside Toulouse Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101951 Documents numériques
en open access
Variations de volume... - pdf auteur -Adobe Acrobat PDF How geographic and climatic factors affect the adaptation of Douglas-fir provenances to the temperate continental climate zone in Europe / Marzena Niemczyk in European Journal of Forest Research, vol 140 n° 6 (December 2021)PermalinkLa modélisation des eaux / Michel Kasser in Géomètre, n° 2197 (décembre 2021)PermalinkModelling the impact of climate change on the occurrence of frost damage in Sitka spruce (Picea sitchensis) in Great Britain / A.A. Atucha-Zamkova in Forestry, an international journal of forest research, vol 94 n° 5 (December 2021)PermalinkSnow cover change assessment in the upper Bhagirathi basin using an enhanced cloud removal algorithm / Mritunjay Kumar Singh in Geocarto international, vol 36 n° 20 ([01/12/2021])PermalinkGIS-based study on the environmental sensitivity to pollution and susceptibility to eutrophication in Burullus Lake, Egypt / Muhammad A. El-Alfy in Marine geodesy, vol 44 n° 6 (November 2021)PermalinkIdentifying surface urban heat island drivers and their spatial heterogeneity in China’s 281 cities: An empirical study based on multiscale geographically weighted regression / Lu Niu in Remote sensing, vol 13 n° 21 (November-1 2021)PermalinkA parameterization of the cloud scattering polarization signal derived from GPM observations for microwave fast radative transfer models / Victoria Sol Galligani in IEEE Transactions on geoscience and remote sensing, vol 59 n° 11 (November 2021)PermalinkEstimation and analysis of GPS inter-fequency clock biases from long-term triple-frequency observations / Fan Zhang in GPS solutions, vol 25 n° 4 (October 2021)PermalinkDetection of aspen in conifer-dominated boreal forests with seasonal multispectral drone image point clouds / Alwin A. Hardenbol in Silva fennica, vol 55 n° 4 (September 2021)PermalinkMonitoring forest disturbance using time-series MODIS NDVI in Michoacán, Mexico / Yao Gao in Geocarto international, vol 36 n° 15 ([15/08/2021])PermalinkComparison of polar ionospheric behavior at Arctic and Antarctic regions for improved satellite-based positioning / Arun Kumar Singh in Journal of applied geodesy, vol 15 n° 3 (July 2021)PermalinkOrogenic collapse and stress adjustments revealed by an intense seismic swarm following the 2015 Gorkha earthquake in Nepal / Lok Bijaya Adhikari in Frontiers in Earth Science, vol 9 (2021)PermalinkPedestrian fowl prediction in open public places using graph convolutional network / Menghang Liu in ISPRS International journal of geo-information, vol 10 n° 7 (July 2021)PermalinkOn the relationship between normalized difference vegetation index and land surface temperature: MODIS-based analysis in a semi-arid to arid environment / Salahuddin M. Jaber in Geocarto international, vol 36 n° 10 ([01/06/2021])PermalinkReference evapotranspiration (ETo) methods implemented as ArcMap models with remote-sensed and ground-based inputs, examined along with MODIS ET, for Peloponnese, Greece / Stavroula Dimitriadou in ISPRS International journal of geo-information, vol 10 n° 6 (June 2021)PermalinkAssessing forest phenology: A multi-scale comparison of near-surface (UAV, spectral reflectance sensor, PhenoCam) and satellite (MODIS, Sentinel-2) remote sensing / Shangharsha Thapa in Remote sensing, vol 13 n° 8 (April-2 2021)PermalinkAssessment of degree-2 order-1 gravitational changes from GRACE and GRACE Follow-on, Earth rotation, satellite laser ranging, and models / Jianli Chen in Journal of geodesy, vol 95 n° 4 (April 2021)PermalinkGeovisualization of COVID-19: State of the art and opportunities / Yu Lan in Cartographica, vol 56 n° 1 (Spring 2021)PermalinkPrecipitable water vapor fusion based on a generalized regression neural network / Bao Zhang in Journal of geodesy, vol 95 n° 4 (April 2021)PermalinkUrban heat island formation in greater Cairo: Spatio-temporal analysis of daytime and nighttime land surface temperatures along the urban–rural gradient / Darshana Athukorala in Remote sensing, vol 13 n° 7 (April-1 2021)Permalink