Centre de documentation
scientifique

Characterization of forests and deforestation in Cambodia using ALOS/PALSAR observation / R. Avtar in Geocarto international, vol 27 n° 2 (March 2012)  

Public [article]  inGeocarto international > vol 27 n° 2 (March 2012) . - pp 119 - 137 Titre : Characterization of forests and deforestation in Cambodia using ALOS/PALSAR observation Type de document : Article/Communication Auteurs : R. Avtar, Auteur ; H. Sawada, Auteur ; Wataru Takeuchi, Auteur ; G. Singh, Auteur Année de publication : 2012 Article en page(s) : pp 119 - 137 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] Cambodge [Termes IGN] caractérisation [Termes IGN] déboisement [Termes IGN] décomposition d'image [Termes IGN] forêt tropicale [Termes IGN] image ALOS-PALSAR [Termes IGN] image radar moirée [Termes IGN] indice de végétation [Termes IGN] sylviculture Résumé : (Auteur) In this study, we have demonstrated the capability of full polarimetric ALOS/Phased Array L-band Synthetic Aperture Radar data for the characterization of the forests and deforestation in Cambodia, to support climate change mitigation policies of Reducing Emission from Deforestation and Forest Degradation (REDD). We have observed mean backscattering coefficient (ó°), entropy (H), alpha angle (á), anisotropy (A), pedestal height (PH), Radar Vegetation Index (RVI) and Freeman–Durden three-component decomposition parameters. The observations show that the forest types and deforested areas are showing variable polarimetric and backscattering properties because of the structural difference. Evergreen forest is characterized by a high value of ó° HV (-12.96 dB) as compared with the deforested area (ó° HV=-22.2 dB). The value of polarimetric parameters such as entropy (0.93), RVI (0.91), PH (0.41) and Freeman–Durden volume scattering (0.43) is high for evergreen forest, whereas deforested area is characterized by the low values of entropy (0.36) and RVI (0.17). Based on these parameters, it is found that ó° HV, entropy, RVI and PH provide best results among other parameters. Numéro de notice : A2012-126 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2011.626081 Date de publication en ligne : 20/10/2011 En ligne : https://doi.org/10.1080/10106049.2011.626081 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31574 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
059-2012021	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Evaluation of modified four-component scattering power decomposition method over highly rugged glaciated terrain / G. Singh in Geocarto international, vol 27 n° 2 (March 2012)  

Public [article]  inGeocarto international > vol 27 n° 2 (March 2012) . - pp 139 - 151 Titre : Evaluation of modified four-component scattering power decomposition method over highly rugged glaciated terrain Type de document : Article/Communication Auteurs : G. Singh, Auteur ; Yasushi Yamaguchi, Auteur ; S. Park, Auteur ; R. Avtar, Auteur Année de publication : 2012 Article en page(s) : pp 139 - 151 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications [Termes IGN] décomposition d'image [Termes IGN] décomposition spectrale [Termes IGN] glace [Termes IGN] Himalaya [Termes IGN] image radar moirée [Termes IGN] polarimétrie radar Résumé : (Auteur) In recent years, there has been increased utilization of fully polarimetric synthetic aperture radar (POLSAR) data to study glaciated terrain features for glaciological and climate change modelling. This article is concerned with more accurate results and appropriate analysis of POLSAR data over a highly rugged glaciated area in Himalayan region. For this purpose, the modified Yamaguchi four-component scattering power decomposition (4-CSPD) method with a rotation concept of 3 x 3 coherency matrix [T] about line of sight is evaluated. It has been found that the modified Yamaguchi 4-CSPD method significantly improved the decomposition results as compared with the original 4-CSPD by minimizing the cross-polarized Horizontal-Vertical (HV) components. This modified 4-CSPD leads to enhancement in the double bounce scattering and surface scattering components and also avoids the overestimation problem in the volume scattering component as compared with the original 4-CSPD from the sloped terrain. The significant reductions of the negative power occurrence in the surface scattering (3.9%) and the double bounce scattering (19.7%) components have also been noticed as compared with the original 4-CSPD method over the glaciated area in this part of the Indian Himalaya. Numéro de notice : A2012-127 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2011.626082 Date de publication en ligne : 20/10/2011 En ligne : https://doi.org/10.1080/10106049.2011.626082 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=31575 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
059-2012021	RAB	Revue	Centre de documentation	En réserve L003	Disponible

Identification and analysis of groundwater potential zones in Ken-Betwa river linking area using remote sensing and geographic information system / R. Avtar in Geocarto international, vol 25 n° 5 (August 2010)  

Public [article]  inGeocarto international > vol 25 n° 5 (August 2010) . - pp 379 - 396 Titre : Identification and analysis of groundwater potential zones in Ken-Betwa river linking area using remote sensing and geographic information system Type de document : Article/Communication Auteurs : R. Avtar, Auteur ; C. Singh, Auteur ; A. Singh, Auteur ; S. Mukherjee, Auteur Année de publication : 2010 Article en page(s) : pp 379 - 396 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] carte thématique [Termes IGN] eau souterraine [Termes IGN] exploration [Termes IGN] hydrogéologie [Termes IGN] identification automatique [Termes IGN] image Landsat-ETM+ [Termes IGN] Inde [Termes IGN] MNS SRTM [Termes IGN] système d'information géographique Résumé : (Auteur) The use of remote sensing data with other ancillary data in a geographic information system (GIS) environment is useful to delineate groundwater potential zonation map of Ken-Betwa river linking area of Bundelkhand. Various themes of information such as geomorphology, land use/land cover, lineament extracted from digital processing of Landsat (ETM+) satellite data of the year 2005 and drainage map were extracted from survey of India topographic sheets, and elevation, slope data were generated from shuttle radar topography mission (SRTM) digital elevation model (DEM). These themes were overlaid to generate groundwater potential zonation (GWPZ) map of the area. The final map of the area shows different zones of groundwater prospects, viz., good (5.22% of the area), moderate (65.83% of the area) poor (15.31% of the area) and very poor (13.64% of area). Numéro de notice : A2010-311 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106041003731318 Date de publication en ligne : 28/05/2010 En ligne : https://doi.org/10.1080/10106041003731318 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=30505 [article]

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
059-2010051	RAB	Revue	Centre de documentation	En réserve L003	Disponible