Centre de documentation
scientifique

Potential flood hazard zone mapping based on geomorphologic considerations and fuzzy analytical hierarchy model in a data scarce West African basin / Olabanji Aladejana in Geocarto international, vol 36 n° 19 ([01/11/2021])  

Public [article]  inGeocarto international > vol 36 n° 19 [01/11/2021] . - pp 2160 - 2185 Titre : Potential flood hazard zone mapping based on geomorphologic considerations and fuzzy analytical hierarchy model in a data scarce West African basin Type de document : Article/Communication Auteurs : Olabanji Aladejana, Auteur ; Ayobami T Salami, Auteur ; Olusola Olufayo Adetoro, Auteur Année de publication : 2021 Article en page(s) : pp 2160 - 2185 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Cartographie thématique [Termes IGN] analyse de sensibilité [Termes IGN] bassin hydrographique [Termes IGN] Bénin [Termes IGN] carte géomorphologique [Termes IGN] cartographie des risques [Termes IGN] indice d'humidité [Termes IGN] inondation [Termes IGN] processus de hiérarchisation analytique floue [Termes IGN] ruissellement [Termes IGN] système d'information géographique Résumé : (auteur) Fuzzy analytical hierarchy process (FAHP) was employed to map and rank flood hazard zones within the Northwest Benin Owena River Basin (NWBORB). Topographic wetness index, elevation, altitude above channel, slope, drainage density, convergence index, and runoff contributing to water accumulation/stagnation were processed to generate the flood hazard map of the basin. Values for the relative importance of each factor for flood occurrence were obtained using FAHP; these factors were super-imposed using weighted overlay. Sensitivity analysis of the weights was conducted to determine their influence on the overall analysis. The resultant flood hazard map was classified into five zones very high, high, moderate, low, and very low. Sensitivity analysis of the result showed that runoff and slope were the most sensitive factors in the analysis with values of 1.163 and 1.132, respectively. A comparison between flood hazard map and historical floods within the basin established the reliability of the methodology. Numéro de notice : A2021-764 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2019.1687595 Date de publication en ligne : 11/11/2019 En ligne : https://doi.org/10.1080/10106049.2019.1687595 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98809 [article]

Soil erosion / António Vieira (2021)  

Public Titre : Soil erosion : current challenges and future perspectives in a changing world Type de document : Monographie Auteurs : António Vieira, Éditeur scientifique Editeur : London [UK] : IntechOpen Année de publication : 2021 Importance : 152 p. ISBN/ISSN/EAN : 978-1-83962-300-4 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] acquisition d'images [Termes IGN] Algérie [Termes IGN] Bénin [Termes IGN] changement d'occupation du sol [Termes IGN] couvert végétal [Termes IGN] érosion côtière [Termes IGN] état du sol [Termes IGN] Ethiopie [Termes IGN] image captée par drone [Termes IGN] image RVB [Termes IGN] indice de végétation [Termes IGN] Indonésie [Termes IGN] modèle RUSLE [Termes IGN] montagne [Termes IGN] occupation du sol [Termes IGN] orthoimage [Termes IGN] photogrammétrie aérienne [Termes IGN] Pix4D [Termes IGN] protection des sols [Termes IGN] risque naturel [Termes IGN] Rwanda [Termes IGN] système d'information géographique Résumé : (Editeur) Soil erosion is a major environmental issue with a worldwide impact and direct and indirect effects on soil productivity and consequently on human survival. Although a natural process, soil erosion has increased significantly due to human intervention, especially in the last centuries, through diverse activities such as intensive agriculture, overgrazing, urban sprawl, deforestation, and industrial and mining activities. Presently, soil erosion and degradation promoted by human action have reached extreme levels, necessitating urgent measures to promote soil conservation and rehabilitation. This book presents perspectives on soil erosion occurring in different parts of the world as well as some successful initiatives and strategies for soil conservation and rehabilitation. Note de contenu : 1. RGB Spectral Indices for the Analysis of Soil Protection by Vegetation Cover against Erosive Processes / Henry Antonio Pacheco Gil and Argenis de Jesús Montilla Pacheco 2. Spatial Estimation of Soil Erosion Risk Using RUSLE/GIS Techniques and Practices Conservation Suggested for Reducing Soil Erosion in Wadi Mina Catchment (Northwest, Algeria) / Ahmed Benchettouh, Sihem Jebari and Lakhdar Kouri 3. Remote Sensing and GIS-Based Soil Loss Estimation Using RUSLE in Bahir Dar Zuria District, Ethiopia / Nurhussen Ahmed Mohammed and Desale Kidane Asmamaw 4. Determination of the Most Priority Conservation Areas Based on Population Pressure and Erosion Hazard Levels in Lesti Sub-Watershed, Malang Regency, Indonesia / Andi Setyo Pambudi 5. The Impacts of Soil Degradation Effects on Phytodiversity and Vegetation Structure on Atacora Mountain Chain in Benin (West Africa) / Farris Okou, Achille Assogbadjo and Brice Augustin Sinsin 6. Erosion Control Success Stories and Challenges in the Context of Sustainable Landscape Management, Rwanda Experience / Jules Rutebuka 7. Biochar: A Sustainable Approach for Improving Soil Health and Environment / Shreya Das, Samanyita Mohanty, Gayatri Sahu, Mausami Rana and Kiran Pilli Numéro de notice : 26759 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Recueil / ouvrage collectif DOI : 10.5772/intechopen.91595 Date de publication en ligne : 12/05/2021 En ligne : https://doi.org/10.5772/intechopen.91595 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99775

Combining optical and radar satellite image time series to map natural vegetation: savannas as an example / Maylis Lopes in Remote sensing in ecology and conservation, vol 6 n° 3 (September 2020)  

Public [article]  inRemote sensing in ecology and conservation > vol 6 n° 3 (September 2020) . - pp 316 - 326 Titre : Combining optical and radar satellite image time series to map natural vegetation: savannas as an example Type de document : Article/Communication Auteurs : Maylis Lopes, Auteur ; Pierre-Louis Frison , Auteur ; Sarah Durante, Auteur ; Henrike Schulte To Bühne, Auteur ; Audrey Ipavec, Auteur ; Vincent Lapeyre, Auteur ; Nathalie Pettorelli, Auteur Année de publication : 2020 Article en page(s) : pp 316 - 326 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] aire protégée [Termes IGN] Bénin [Termes IGN] carte d'occupation du sol [Termes IGN] carte de la végétation [Termes IGN] écosystème [Termes IGN] image Sentinel-MSI [Termes IGN] image Sentinel-SAR [Termes IGN] protection de l'environnement [Termes IGN] protection de la biodiversité [Termes IGN] savane [Termes IGN] série temporelle Résumé : (auteur) Up-to-date land cover maps are important for biodiversity monitoring as they are central to habitat and ecosystem distribution assessments. Satellite remote sensing is a key technology for generating these maps. Until recently, land cover mapping has been limited to static approaches, which have primarily led to the production of either global maps at coarse spatial resolutions or geographically restricted maps at high spatial resolutions. The recent availability of optical (Sentinel-2) and radar (Sentinel-1) satellite image time series (SITS) which provide access to high spatial and very high temporal resolutions, is a game changer, offering opportunities to map land cover using both temporal and spatial information. These data moreover open interesting perspectives for land cover mapping based on data combination approach. However, the usefulness of combining dense time series (more than 30 images per year) and data combination approaches to map natural vegetation has so far not been assessed. To address this gap, this contribution tests the idea that the combined consideration of optical and radar data combination and time series analyses can significantly improve natural vegetation mapping in the Pendjari National Park, a Sahelian savanna protected area in Benin. Results highlight that the combination of Sentinel-1 and Sentinel-2 SITS performs as well as Sentinel-2 SITS alone in terms of classification accuracy. Land cover maps are however qualitatively better when considering the data combination approach. Our results also clearly show that the use of dense/hypertemporal optical time series significantly improves classification outcomes compared to using multitemporal only a few images per year) or monotemporal data. Altogether, this work thus demonstrates the ability of dense SITS to improve discrimination of natural vegetation types using information on their phenology, leading to more detailed and more reliable maps for environmental management. Numéro de notice : A2020-871 Affiliation des auteurs : UGE-LASTIG+Ext (2020- ) Thématique : BIODIVERSITE/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/rse2.139 Date de publication en ligne : 17/01/2020 En ligne : https://doi.org/10.1002/rse2.139 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99584 [article]

Mapping and estimating land change between 2001 and 2013 in a heterogeneous landscape in West Africa: Loss of forestlands and capacity building opportunities / Hèou Maléki Badjana in International journal of applied Earth observation and geoinformation, vol 63 (December 2017)  

Public [article]  inInternational journal of applied Earth observation and geoinformation > vol 63 (December 2017) . - pp 15 - 23 Titre : Mapping and estimating land change between 2001 and 2013 in a heterogeneous landscape in West Africa: Loss of forestlands and capacity building opportunities Type de document : Article/Communication Auteurs : Hèou Maléki Badjana, Auteur ; Pontus Olofsson, Auteur ; Curtis E. Woodcock, Auteur ; Jörg Helmschrot, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 15 - 23 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection [Termes IGN] Afrique occidentale [Termes IGN] analyse diachronique [Termes IGN] Bénin [Termes IGN] changement d'occupation du sol [Termes IGN] classification par forêts d'arbres décisionnels [Termes IGN] déboisement [Termes IGN] forêt [Termes IGN] image Landsat-8 [Termes IGN] image Landsat-ETM+ [Termes IGN] image Landsat-OLI [Termes IGN] logiciel libre [Termes IGN] occupation du sol [Termes IGN] Orfeo Tool Box [Termes IGN] QGIS [Termes IGN] Togo Résumé : (auteur) In West Africa, accurate classification of land cover and land change remains a big challenge due to the patchy and heterogeneous nature of the landscape. Limited data availability, human resources and technical capacities, further exacerbate the challenge. The result is a region that is among the more understudied areas in the world, which in turn has resulted in a lack of appropriate information required for sustainable natural resources management. The objective of this paper is to explore open source software and easy-to-implement approaches to mapping and estimation of land change that are transferrable to local institutions to increase capacity in the region, and to provide updated information on the regional land surface dynamics. To achieve these objectives, stable land cover and land change between 2001 and 2013 in the Kara River Basin in Togo and Benin were mapped by direct multitemporal classification of Landsat data by parameterization and evaluation of two machine-learning algorithms. Areas of land cover and change were estimated by application of an unbiased estimator to sample data following international guidelines. A prerequisite for all tools and methods was implementation in an open source environment, and adherence to international guidelines for reporting land surface activities. Findings include a recommendation of the Random Forests algorithm as implemented in Orfeo Toolbox, and a stratified estimation protocol − all executed in the QGIS graphical use interface. It was found that despite an estimated reforestation of 10,0727 ± 3480 ha (95% confidence interval), the combined rate of forest and savannah loss amounted to 56,271 ± 9405 ha (representing a 16% loss of the forestlands present in 2001), resulting in a rather sharp net loss of forestlands in the study area. These dynamics had not been estimated prior to this study, and the results will provide useful information for decision making pertaining to natural resources management, land management planning, and the implementation of the United Nations Collaborative Programme on Reducing Emissions from Deforestation and Forest Degradation in Developing Countries (UN-REDD). Numéro de notice : A2017-411 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jag.2017.07.006 En ligne : https://doi.org/10.1016/j.jag.2017.07.006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=86298 [article]

UAS Experiences in Africa / Marius Schrôder in GIM international, vol 29 n° 12 (December 2015)

Public [article]  inGIM international > vol 29 n° 12 (December 2015) . - pp 21- 23 Titre : UAS Experiences in Africa Type de document : Article/Communication Auteurs : Marius Schrôder, Auteur Année de publication : 2015 Article en page(s) : pp 21- 23 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Topographie moderne [Termes IGN] Afrique équatoriale [Termes IGN] Bénin [Termes IGN] climat équatorial [Termes IGN] conditions de travail [Termes IGN] drone [Termes IGN] instrument de géodésie [Termes IGN] instrument de nivellement [Termes IGN] savane Résumé : (auteur) When conducting surveys in countries near the equator, environmental conditions can be harsh. Heat, dust and humidity may disrupt sensitive equipment, white distrustful locals may obstruct the undertaking. The author shares experiences of carrying out a UAS survey on the savannah of Benin, West Africa. Numéro de notice : A2015-830 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79129 [article]

Land cover changes assessment using object-based image analysis in the Binah River watershed (Togo and Benin) / Hèou Maléki Badjana in Earth and space science, vol 2 n° 10 (October 2015)  

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Land water storage changes from ground and space geodesy : first results from the GHYRAF (Gravity and Hydrology in Africa) experiment / Jacques Hinderer in Pure and applied geophysics, vol 169 n° 8 (August 2012)  

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Mesoscale water cycle within the West African Monsoon / Christophe Peugeot in Atmospheric Science Letters, vol 12 n° 1 (January - March 2011)  

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Diurnal cycle of the intertropical discontinuity over West Africa analysed by remote sensing and mesoscale modelling / Bernhard Pospichal in Quarterly Journal of the Royal Meteorological Society, vol 136 n° S1 (January 2010)    

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Carnets de voyage / T. Lamazou (1998)

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Levés gravimétriques de reconnaissance / D.B. Boukeke (1996)

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Quand le "petit disque" remplacera-t-il le "grand livre" Cabral collection et l'atlas informatise du Togo et du Bénin ? / B. Antheaume in Mappemonde, vol 1994 n° 2 (juin 1994)    

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Integrated environmental cartography / Unesco (1987)

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Contribution à l'étude du gisement solaire en Afrique de l'ouest à l'aide de Météosat / A. Werem (1984)

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Liste des divisions administratives des états africains d'expression française au sud du Sahara / Claude Perrichet (1981)

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