{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,16]],"date-time":"2026-04-16T08:04:31Z","timestamp":1776326671838,"version":"3.50.1"},"reference-count":64,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T00:00:00Z","timestamp":1621296000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Remote Sensing"],"abstract":"<jats:p>The mangrove areas in Senegal have fluctuated considerably over the last few decades, and it is therefore important to monitor the evolution of forest cover in order to orient and optimise forestry policies. This study presents a method for mapping plant formations to monitor and study changes in zonation within the mangroves of Senegal. Using Landsat ETM+ and Landsat 8 OLI images merged to a 15-m resolution with a pansharpening method, a processing chain that combines an OBIA approach and linear spectral unmixing was developed to detect changes in mangrove zonation through a diachronic analysis. The accuracy of the discriminations was evaluated with kappa indices, which were 0.8 for the Saloum delta and 0.83 for the Casamance estuary. Over the last 20 years, the mangroves of Senegal have increased in surface area. However, the dynamics of zonation differ between the two main mangrove hydrosystems of Senegal. In Casamance, a colonisation process is underway. In the Saloum, Rhizophora mangle is undergoing a process of densification in mangroves and appears to reproduce well in both regions. Furthermore, this study confirms, on a regional scale, observations in the literature noting the lack of Avicennia germinans reproduction on a local scale. In the long term, these regeneration gaps may prevent the mangrove from colonising the upper tidal zones in the Saloum. Therefore, it would be appropriate to redirect conservation policies towards reforestation efforts in the Saloum rather than in Casamance and to focus these actions on the perpetuation of Avicennia germinans rather than Rhizophora mangle, which has no difficulty in reproducing. From this perspective, it is necessary to gain a more in-depth understanding of the specific factors that promote the success of Avicennia germinans seeding.<\/jats:p>","DOI":"10.3390\/rs13101961","type":"journal-article","created":{"date-parts":[[2021,5,18]],"date-time":"2021-05-18T12:17:16Z","timestamp":1621340236000},"page":"1961","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Mapping Mangrove Zonation Changes in Senegal with Landsat Imagery Using an OBIA Approach Combined with Linear Spectral Unmixing"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2629-7645","authenticated-orcid":false,"given":"Florent","family":"Lombard","sequence":"first","affiliation":[{"name":"Department of Geography, CNRS UMR Espace Campus Valrose, Universit\u00e9 C\u00f4te d\u2019Azur, B\u00e2timent L 28, Avenue de Valrose, CEDEX 2, 06108 Nice, France"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0031-1672","authenticated-orcid":false,"given":"Julien","family":"Andrieu","sequence":"additional","affiliation":[{"name":"GEOSpatial Monitoring &amp; Information Technology (GeoSMIT) Department, French Institute of Pondicherry (IFP), UMIFRE 21 CNRS-MEAE\/USR 3330, 11 St. Louis Street, P.B. 33, Pondicherry 605001, India"}]}],"member":"1968","published-online":{"date-parts":[[2021,5,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"89","DOI":"10.1146\/annurev-environ-101718-033302","article-title":"The State of the World\u2019s Mangrove Forests: Past, Present, and Future","volume":"44","author":"Friess","year":"2019","journal-title":"Annu. Rev. Environ. Resour."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"870","DOI":"10.1038\/s41559-019-0861-y","article-title":"Better restoration policies are needed to conserve mangrove ecosystems","volume":"3","author":"Lee","year":"2019","journal-title":"Nat. Ecol. Evol."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Otero, V., Van De Kerchove, R., Satyanarayana, B., Mohd-Lokman, H., Lucas, R., and Dahdouh-Guebas, F. (2020). An analysis of the early regeneration of mangrove forests using landsat time series in the Matang mangrove forest reserve, Peninsular Malaysia. Remote Sens., 11.","DOI":"10.3390\/rs11070774"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"41","DOI":"10.1126\/science.317.5834.41b","article-title":"A World Without Mangroves?","volume":"317","author":"Duke","year":"2007","journal-title":"Science"},{"key":"ref_5","unstructured":"Brondizio, E.S., Settele, J., D\u00edaz, S., and Ngo, H.T. (2019). Global Assessment Report on Biodiversity and Ecosystem Services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services, IPBES secretariat."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1038\/ngeo1123","article-title":"Mangroves among the most carbon-rich forests in the tropics","volume":"4","author":"Donato","year":"2011","journal-title":"Nat. Geosci."},{"key":"ref_7","unstructured":"Alongi, D.M. (2012). Introduction in the Energetics of Mangrove Forests, Springer Science and Business Media BV."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"R153","DOI":"10.1016\/j.cub.2019.12.054","article-title":"Mangroves give cause for conservation optimism, for now","volume":"30","author":"Friess","year":"2020","journal-title":"Curr. Biol."},{"key":"ref_9","doi-asserted-by":"crossref","unstructured":"Saenger, P. (2002). Mangrove Ecology, Silviculture and Conservation, Kluwer Academic Publishers.","DOI":"10.1007\/978-94-015-9962-7"},{"key":"ref_10","unstructured":"Spalding, M., Kainuma, M., and Collins, L. (2010). World Atlas of Mangroves, Earthscan. A Collaborative Project of ITTO, ISME, FAO, UNEP-WCMC, UNESCO-MAB, UNU-INWEH and TNC. 2010."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"105001","DOI":"10.1016\/j.ocecoaman.2019.105001","article-title":"Mangrove use and management within the Sine-Saloum Delta, Senegal","volume":"185","author":"Gallup","year":"2020","journal-title":"Ocean Coast. Manag."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"220","DOI":"10.1016\/j.aquabot.2008.02.009","article-title":"Ethnobiology, socio-economics and management of mangrove forests: A review","volume":"89","author":"Walters","year":"2008","journal-title":"Aquat. Bot."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Cormier-Salem, M. (1991). Dynamique et Usages de la Mangrove Dans les Pays des Rivi\u00e8res du Sud, du S\u00e9n\u00e9gal \u00e0 la Sierra Leone, IRD \u00c9ditions.","DOI":"10.4000\/books.irdeditions.3642"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1186\/1746-4269-2-24","article-title":"Analysing ethnobotanical and fishery-related importance of mangroves of East-Godavari Delta (Andhra Pradesh, India) for conservation and management purposes","volume":"2","author":"Collin","year":"2006","journal-title":"J. Ethnobiol. Ethnomed."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"2","DOI":"10.1016\/j.aquaculture.2015.02.001","article-title":"Aquaculture environment interactions: Past, present and likely future trends","volume":"447","author":"Edwards","year":"2015","journal-title":"Aquaculture"},{"key":"ref_16","unstructured":"FAO (2007). The World\u2019s Mangroves 1980\u20132005, \u00c9tude FAO."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"7117","DOI":"10.1038\/s41598-020-63880-1","article-title":"Global trends in mangrove forest fragmentation","volume":"10","author":"Connolly","year":"2020","journal-title":"Sci. Rep."},{"key":"ref_18","unstructured":"FAO (2020). Global Forest Resources Assessment 2020: Main Report, FAO."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1080\/22797254.2018.1432295","article-title":"Land cover changes on the West-African coastline from the Saloum Delta (Senegal) to Rio Geba (Guinea-Bissau) between 1979 and 2015","volume":"51","author":"Andrieu","year":"2018","journal-title":"Eur. J. Remote Sens."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"117963","DOI":"10.1016\/j.foreco.2020.117963","article-title":"Botanical field-study and remote sensing to describe mangrove resilience in the Saloum Delta (Senegal) after 30 years of degradation narrative","volume":"461","author":"Andrieu","year":"2020","journal-title":"For. Ecol. Manag."},{"key":"ref_21","unstructured":"Dieye, E.H.B., Diaw, A.T., San\u00e9, T., Ndour, N., and Ndour, N. (2013). Dynamique de la mangrove de l\u2019estuaire du Saloum (S\u00e9n\u00e9gal) entre 1972 et 2010. Cybergeo Eur. J. Geogr., doc 629."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"214","DOI":"10.1016\/j.gloenvcha.2019.01.003","article-title":"Transborder political ecology of mangroves in Senegal and The Gambia","volume":"54","author":"Fent","year":"2019","journal-title":"Glob. Environ. Chang."},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Descroix, L., San\u00e9, Y., Thior, M., Manga, S.-P., Ba, B.D., Mingou, J., Mendy, V., Coly, S., Di\u00e8ye, A., and Badiane, A. (2020). Inverse Estuaries in West Africa: Evidence of the Rainfall Recovery?. Water, 12.","DOI":"10.3390\/w12030647"},{"key":"ref_24","doi-asserted-by":"crossref","unstructured":"Nicholson, S.E. (2013). The West African Sahel: A review of recent studies on the rainfall regime and its interannual variability (Article ID 453521). ISRN Meteorol., 32.","DOI":"10.1155\/2013\/453521"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"2105","DOI":"10.1002\/hyp.9813","article-title":"The rivers of Africa: Witness of climate change and human impact on the environment","volume":"27","author":"Lienou","year":"2013","journal-title":"Hydrol. Process."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2907","DOI":"10.5194\/bg-12-2907-2015","article-title":"Assessing vegetation structure and ANPP dynamics in a grassland\u2013shrubland Chihuahuan ecotone using NDVI\u2013rainfall relationships","volume":"12","author":"Turnbull","year":"2015","journal-title":"Biogeosciences"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"413","DOI":"10.1111\/avsc.12232","article-title":"Semi-arid vegetation response to antecedent climate and water balance windows","volume":"19","author":"Thoma","year":"2016","journal-title":"Appl. Veg. Sci."},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"112108","DOI":"10.1016\/j.rse.2020.112108","article-title":"Characterizing vegetation response to rainfall at multiple temporal scales in the Sahel-Sudano-Guinean region using transfer function analysis","volume":"252","author":"Zhou","year":"2021","journal-title":"Remote Sens. Environ."},{"key":"ref_29","unstructured":"Holling, C.S. (1978). Adaptive Environmental Assessment and Management, John Wiley and Sons."},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"578","DOI":"10.1016\/j.isprsjprs.2008.04.002","article-title":"An object-based method for mapping and change analysis in mangrove ecosystems","volume":"63","author":"Conchedda","year":"2008","journal-title":"ISPRS J. Photogramm. Remote Sens."},{"key":"ref_31","unstructured":"Artaud, H., and Surall\u00e9s, A. (2017). Mangrove Grabbing: An Exploration of Changes in Mangrove Tenure from a Political Ecology Perspective, IWGIA. The Sea within: Maritime Tenure and Cosmopolitical Debates."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"89","DOI":"10.2989\/16085914.2016.1146122","article-title":"Mangrove reforestation in question: Greening or grabbing coastal zones and deltas?","volume":"41","author":"Panfili","year":"2016","journal-title":"Afr. J. Aquat. Sci."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"107160","DOI":"10.1016\/j.ecss.2020.107160","article-title":"The perceptions of stakeholders on current management of mangroves in the Sine-Saloum Delta, Senegal, Estuarine","volume":"248","author":"Arumugam","year":"2021","journal-title":"Coast. Shelf Sci."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"51","DOI":"10.19182\/bft2020.346.a36296","article-title":"La population d\u2019Avicennia germinans du delta du Saloum est-elle relictuelle depuis la derni\u00e8re p\u00e9riode humide?","volume":"346","author":"Lombard","year":"2020","journal-title":"Bois et For\u00eats des Trop."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"154","DOI":"10.1111\/j.1466-8238.2010.00584.x","article-title":"Status and distribution of mangrove forests of the world using earth observation satellite data","volume":"20","author":"Giri","year":"2011","journal-title":"Glob. Ecol. Biogeogr."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"878","DOI":"10.3390\/rs3050878","article-title":"Remote Sensing of Mangrove Ecosystems: A Review","volume":"3","author":"Kuenzer","year":"2011","journal-title":"Remote Sens."},{"key":"ref_37","doi-asserted-by":"crossref","unstructured":"Wang, D., Wan, B., Qiu, P., Su, Y., Guo, Q., Wang, R., Sun, F., and Wu, X. (2018). Evaluating the Performance of Sentinel-2, Landsat 8 and Pl\u00e9iades-1 in Mapping Mangrove Extent and Species. Remote Sens., 10.","DOI":"10.3390\/rs10091468"},{"key":"ref_38","doi-asserted-by":"crossref","unstructured":"Taureau, F., Robin, M., Proisy, C., Fromard, F., Imbert, D., and Debaine, F. (2019). Mapping the Mangrove Forest Canopy Using Spectral Unmixing of Very High Spatial Resolution Satellite Images. Remote Sens., 11.","DOI":"10.3390\/rs11030367"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"5655","DOI":"10.1080\/014311602331291215","article-title":"Integration of object-based and pixel-based classification for mapping mangroves with IKONOS imagery","volume":"25","author":"Wang","year":"2004","journal-title":"Int. J. Remote Sens."},{"key":"ref_40","unstructured":"Lombard, F., Andrieu, J., and Josselin, D. (2021). Object-oriented classification-based mapping of mangrove zonation in Casamance and Sine-Saloum (Senegal) using Sentinel-2 images. Geo-Spat. Inf. Sci., submitted for publication."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"507","DOI":"10.3390\/ijgi3020507","article-title":"Effects of Pansharpening on Vegetation Indices","volume":"3","author":"Johnson","year":"2014","journal-title":"ISPRS Int. J. Geo-Inf."},{"key":"ref_42","first-page":"20","article-title":"Coastal Change Detection using GIS in Setiu Lagoon, Terengganu, Malaysia","volume":"1","author":"Kasawani","year":"2010","journal-title":"J. GIS Trends"},{"key":"ref_43","first-page":"19","article-title":"Evaluation of Vegetation density of the Mangrove forest in South Andaman Island using Remote Sensing and GIS techniques","volume":"3","author":"Yuvaraj","year":"2014","journal-title":"Int. Res. J. Environ. Sci."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"436","DOI":"10.1016\/j.proenv.2016.03.094","article-title":"Mapping and Monitoring of Mangrove Density Changes on tin Mining Area","volume":"33","author":"Sari","year":"2016","journal-title":"Procedia Environ. Sci."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"188","DOI":"10.2747\/1548-1603.45.2.188","article-title":"Identifying Mangrove Species and Their Surrounding Land Use and Land Cover Classes Using an Object-Oriented Approach with a Lacunarity Spatial Measure","volume":"45","author":"Myint","year":"2008","journal-title":"GISci. Remote Sens."},{"key":"ref_46","unstructured":"Taureau, F. (2017). Cartographie Harmonis\u00e9e des Mangroves de L\u2019outre-Mer Fran\u00e7ais. Th\u00e8se de Doctorat. Sciences de L\u2019environnement; Universit\u00e9 de Nantes (UNAM), Nantes, France, 2017. [Doctorat Th\u00e8se, Universit\u00e9 de Nantes (UNAM)]. Sciences de L\u2019environnement."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"144","DOI":"10.1016\/j.csr.2017.07.007","article-title":"Temporal patterns in species zonation in a mangrove forest in the Mekong Delta, Vietnam, using a time series of Landsat imagery","volume":"147","author":"Bullock","year":"2017","journal-title":"Cont. Shelf Res."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"193","DOI":"10.1016\/j.rse.2017.05.006","article-title":"Enhanced forest cover mapping using spectral unmixing and object-based classification of multi-temporal Landsat imagery","volume":"196","author":"Pontius","year":"2017","journal-title":"Remote Sens. Environ."},{"key":"ref_49","unstructured":"Descroix, L. (2018). Processus et Enjeux D\u2019eau en Afrique de L\u2019ouest Soudano-Sah\u00e9lienne, EAC."},{"key":"ref_50","first-page":"337","article-title":"Correctly assessing forest change in a priority West African mangrove ecosystem: 1986\u20132010 An answer to Carney et al., 2014 paper \u201cAssessing forest change in a priority West African mangrove ecosystem: 1986\u20132010\u201d","volume":"13","author":"Andrieu","year":"2019","journal-title":"Remote Sens. App. Soc. Environ."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"107308","DOI":"10.1016\/j.ecss.2021.107308","article-title":"An alternative approach to delineate wetland influence zone of a tropical intertidal mudflat using geo-information technology","volume":"253","author":"Datta","year":"2021","journal-title":"Estuar. Coast. Shelf Sci."},{"key":"ref_52","unstructured":"Taureau, F. (2018). Evaluation des Donn\u00e9es Sentinel Pour la Mise en Place D\u2019un Syst\u00e8me de Surveillance des Mangroves \u00e0 Mayotte, Universit\u00e9 de Nantes."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"159","DOI":"10.2307\/2529310","article-title":"The measurement of observer agreement for categorical data","volume":"33","author":"Landis","year":"1977","journal-title":"Biometrics"},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.rse.2014.02.015","article-title":"Good practices for estimating area an assessing accuracy of land change","volume":"148","author":"Olofsson","year":"2014","journal-title":"Remote Sens. Environ."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1016\/j.ecss.2011.05.032","article-title":"The influence of natural and anthropogenic factors on mangrove dynamics over 60 years: The Somone Estuary Senegal","volume":"94","author":"Sakho","year":"2011","journal-title":"Estuar. Coast. Shelf Sci."},{"key":"ref_56","first-page":"118","article-title":"Dynamique de la Mangrove de Thiobon dans l\u2019estuaire de la Casamance (S\u00e9n\u00e9gal) entre 1972 et 2017","volume":"14","author":"Solly","year":"2018","journal-title":"Eur. Sci. J."},{"key":"ref_57","first-page":"1","article-title":"Dynamique spatio-temporelle de la mangrove de Kafountine dans l\u2019estuaire de la Basse-Casamance des ann\u00e9es 1972 \u00e0 nos jours: Approche par t\u00e9l\u00e9d\u00e9tection","volume":"10","author":"Fall","year":"2020","journal-title":"IOSR J. Eng. (IOSRJEN)"},{"key":"ref_58","doi-asserted-by":"crossref","unstructured":"Hogarth, P.J. (2007). The Biology of Mangroves and Seagrasses, Biology of Habitats, 2 ed.; Oxford University Press.","DOI":"10.1093\/acprof:oso\/9780198568704.001.0001"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"299","DOI":"10.4000\/geocarrefour.9306","article-title":"L\u2019impact des changements d\u00e9mographiques et socio-\u00e9conomiques sur la perception et la gestion de la mangrove en Basse Casamance (S\u00e9n\u00e9gal)","volume":"88","author":"Bassene","year":"2013","journal-title":"G\u00e9ocarrefour"},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"543","DOI":"10.1111\/j.1365-3091.1985.tb00469.x","article-title":"Evidence of dynamics reversal in tropical estuaries, geomorphological and sedimentological consequences (Salum and Casamance Rivers, Senegal)","volume":"32","author":"Barusseau","year":"1985","journal-title":"Sedimentology"},{"key":"ref_61","unstructured":"Diop, E.S. (1990). La C\u00f4te Ouest Africaine du Saloum (S\u00e9n\u00e9gal) \u00e0 la Mellacor\u00e9e (R\u00e9publique de Guin\u00e9e). [Ph.D. Thesis, Universit\u00e9 Louis Pasteur]."},{"key":"ref_62","unstructured":"Marius, C. (1985). Mangroves du S\u00e9n\u00e9gal et de la Gambie. Ecologie, P\u00e9dologie, G\u00e9ochimie, Mise en Valeur et Am\u00e9nagement. [Ph.D. Thesis, Louis Pasteur Strasbourg University]."},{"key":"ref_63","unstructured":"Diouf, A.C. (2019). Dynamiques Des Ressources Naturelles et Adaptations Des Soci\u00e9t\u00e9s Dans la R\u00e9serve de Biosph\u00e8re du Delta du Saloum au S\u00e9n\u00e9gal. [Ph.D. Thesis, Universit\u00e9 Gaston Berg\u00e9]."},{"key":"ref_64","unstructured":"Olivry, J.-C. (1987). Les cons\u00e9quences durables de la s\u00e9cheresse actuelle sur l\u2019\u00e9coulement du fleuve S\u00e9n\u00e9gal et l\u2019hypersalinisation de la Basse-Casamance. Influence of Climate Change and Climatic Variability on the Hydrologie Regime and Water Resources, IAHS Publisher."}],"container-title":["Remote Sensing"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/10\/1961\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:03:15Z","timestamp":1760162595000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2072-4292\/13\/10\/1961"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,5,18]]},"references-count":64,"journal-issue":{"issue":"10","published-online":{"date-parts":[[2021,5]]}},"alternative-id":["rs13101961"],"URL":"https:\/\/doi.org\/10.3390\/rs13101961","relation":{},"ISSN":["2072-4292"],"issn-type":[{"value":"2072-4292","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,5,18]]}}}