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Le Tchad Des Lacs Les Zones Humides Sahéliennes Au Défi Du Changement Global Christine Raimond, Florence Sylvestre, Dangbet Zakinet Et Abderamane Moussa (Éd.)

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Le Tchad Des Lacs Les Zones Humides Sahéliennes Au Défi Du Changement Global Christine Raimond, Florence Sylvestre, Dangbet Zakinet Et Abderamane Moussa (Éd.) Le Tchad des lacs Les zones humides sahéliennes au défi du changement global Christine Raimond, Florence Sylvestre, Dangbet Zakinet et Abderamane Moussa (éd.) DOI : 10.4000/books.irdeditions.30450 Éditeur : IRD Éditions Lieu d'édition : Marseille Année d'édition : 2019 Date de mise en ligne : 29 août 2019 Collection : Synthèses ISBN électronique : 9782709927161 http://books.openedition.org Édition imprimée Date de publication : 1 juin 2019 ISBN : 9782709927154 Nombre de pages : 368 Référence électronique RAIMOND, Christine (dir.) ; et al. Le Tchad des lacs : Les zones humides sahéliennes au défi du changement global. Nouvelle édition [en ligne]. Marseille : IRD Éditions, 2019 (généré le 21 décembre 2020). Disponible sur Internet : <http://books.openedition.org/irdeditions/30450>. ISBN : 9782709927161. DOI : https://doi.org/10.4000/books.irdeditions.30450. © IRD Éditions, 2019 Conditions d’utilisation : http://www.openedition.org/6540 Le Tchad des lacs Les zones humides sahéliennes au défi du changement global Christine Raimond, Florence Sylvestre, Dangbet Zakinet et Abderamane Moussa (éd.) Éditeur : IRD Éditions Lieu d'édition : Marseille Année d'édition : 2019 Date de mise en ligne : 29 août 2019 Collection : Synthèses http://books.openedition.org Édition imprimée Date de publication : 1 juin 2019 Nombre de pages : 368 Ce document vous est offert par OpenEdition Center USR 2004 Référence électronique RAIMOND, Christine (dir.) ; et al. Le Tchad des lacs : Les zones humides sahéliennes au défi du changement global. Nouvelle édition [en ligne]. Marseille : IRD Éditions, 2019 (généré le 29 août 2019). Disponible sur Internet : <http://books.openedition.org/irdeditions/30450>. © IRD Éditions, 2019 Conditions d’utilisation : http://www.openedition.org/6540 Le Tchad des lacs Les zones humides sahéliennes au défi du changement global Le Tchad des lacs Les zones humides sahéliennes au défi du changement global Éditeurs scientifiques Christine RAIMOND, Florence SYLVESTRE, Dangbet ZAKINET, Abderamane MOUSSA Ce volume a bénéficié du soutien financier de l’Ambassade de France au Tchad. IRD Éditions INSTITUT DE RECHERCHE POUR LE DÉVELOPPEMENT Collection Synthèses Marseille, 2019 Coordination éditoriale Sylvie Hart Préparation éditoriale Stéphanie Quillon (34) Mise en page Desk (53) Maquette de couverture Michelle S aint-Léger Maquette intérieure Pierre Lopez Photo de couverture Livraison de fourrage à Yao. L’augmentation des populations sédentaires et transhumantes et de leur bétail accroît fortement la pression sur les ressources (Yao, février 2016). © CNRS/M. Schuster p. 4 de couverture Multifonctionnalité de l’espace en bordure du lac Fitri (Gamsa, janvier 2016). Les jardins maraîchers et la pêche entravent le passage saisonnier des troupeaux vers les bourgoutières sur les îles. © CNRS/C. Raimond La loi du 1er juillet 1992 (code de la propriété intellectuelle, première partie) n’autorisant, aux termes des alinéas 2 et 3 de l’article L. 122-5, d’une part, que les « copies ou reproductions strictement réser- vées à l’usage du copiste et non destinées à une utilisation collective » et, d’autre part, que les analyses et les courtes citations dans le but d’exemple ou d’illustration, « toute représentation ou reproduction intégrale ou partielle faite sans le consentement de l’auteur ou de ses ayants droit ou ayants cause, est illicite » (alinéa 1er de l’article L. 122-4). Cette représentation ou reproduction, par quelque procédé que ce soit, constituerait donc une contre- façon passible des peines prévues au titre III de la loi précitée. © IRD, 2019 ISBN : 978-2-7099-2715-4 Composition du comité scientifique Likius ANDOSSA Abderamane MOUSSA paléontologue, université de N’Djamena, géologue, université de N’Djamena, Tchad Tchad Sougnabé PABAME Ali Brahim BECHIR socioéconomiste, Institut de recherche pastoraliste, Institut national d’élevage en élevage pour le développement, Tchad de Moussoro, Tchad Christine RAIMOND Tchago BOUIMON géographe, Centre national archéologue, université de N’Djamena, de la recherche scientifique, France Tchad Frédéric REOUNODJI Mirjam de BRUIJN géographe, ministère de l’Enseignement anthropologue, université de Leyde, supérieur et de l’Innovation, Tchad Pays-Bas Mathieu SCHUSTER Guillaume FAVREAU géologue, Centre national de la recherche hydrogéochimiste, Institut de recherche scientifique, France pour le développement, Niger Florence SYLVESTRE Abderamane HAMIT paléoclimatologue, Institut de recherche hydrogéochimiste, université pour le développement, France de N’Djamena, Tchad Christine VALLET-COULOMB Olivier LANGLOIS hydrogéochimiste, Aix-Marseille Université, archéologue, Centre national France de la recherche scientifique, France Nicolas WALDMANN Jacques LEMOALLE paléoclimatologue, université Haifa, Israel hydroécologue, Institut de recherche pour le développement, France Dangbet ZAKINET chef de mission, lac Fitri, historien, Robert MADJIGOTO université de N’Djamena, Tchad géographe, université de N’Djamena, Tchad Géraud MAGRIN géographe, université Paris 1 Panthéon-Sorbonne, France Sommaire Préface ................................................................. 11 Remerciements ......................................................... 13 Introduction ........................................................... 15 Christine Raimond, Florence Sylvestre, Dangbet Zakinet, Abderamane Moussa Partie 1 Les lacs tchadiens du Pléistocène à l’Anthropocène........... 33 Introduction ........................................................... 35 Christine Raimond, Florence Sylvestre Chapitre 1 Changements environnementaux et climatiques à la période humide africaine Holocène dans le bassin du lac Fitri (Tchad) ................................................... 39 Mathieu Schuster, Florence Sylvestre, Christine Raimond, Abderamane Moussa, Yassine Abakar, Tashi Yalikun Chapitre 2 Paléoenvironnements et variations paléohydrologiques du lac Tchad au cours des 12 000 dernières années ................ 53 Florence Sylvestre, Pierre Deschamps, Adoum Bari Sinine, Remadji Rirongarti, Jean-Charles Mazur, Nicolas Waldmann, Paula do Amaral, Camille Bouchez, Jean-Claude Doumnang Chapitre 3 Des hommes et des lacs. Peuplement des zones lacustres du Borkou (Tchad) à l’Holocène ........................................................... 65 Yves Gauthier, Christine Gauthier Le Tchad des lacs Chapitre 4 Mission archéologique franco-tchadienne aux lacs d’Ounianga (Tchad). Principaux résultats des deux premières missions de terrain .............................................................. 85 Vincent Mourre, Guemona Djimet, Tchago Bouimon, Marie-Pierre Coustures, Barbara Eichhorn, Jean Mbairo, Caroline Robion-Brunner, Margareta Tengberg Chapitre 5 Variabilité des crues et des paysages du lac Fitri depuis les grandes sécheresses des années 1970-1980 ............. 99 Tashi Yalikun, Christine Raimond, Angeline Kemsol Nagorngar, Dangbet Zakinet, Mathieu Schuster, Florence Sylvestre Partie 2 Dynamique des socioécosystèmes lacustres ................... 121 Introduction ........................................................... 123 Christine Raimond, Florence Sylvestre Chapitre 6 Les lacs d’Ounianga. Mieux comprendre leur dynamique hydrologique et écologique par une approche interdisciplinaire .................. 127 Thijs Van der Meeren, Pierre Deschamps, Florence Sylvestre, Baouyé Kemkong, Abderamane Moussa, Mathieu Schuster, Dirk Verschuren Chapitre 7 Étude de la dynamique hydrologique des lacs Iro et Fitri par une approche isotopique ......................................... 139 Chloé Poulin, Bruno Hamelin, Christine Vallet-Coulomb, Guinbé Amngar, Bichara Loukman, Jean-François Crétaux, Jean-Claude Doumnang, Abdallah Mahamat Nour, Guillemette Menot, Florence Sylvestre, Pierre Deschamps Chapitre 8 Caractérisation des paramètres physicochimiques des eaux souterraines de la région du lac Iro ....................... 155 Guinbé Amngar, Abderamane Hamit Chapitre 9 Fluctuation des récoltes de sorgho repiqué et potentialités de culture. Une analyse par télédétection dans la région du lac Fitri ......... 173 Angeline Kemsol Nagorngar, Christine Raimond, Robert Madjigoto, Valère Jofack Sokeng, Datoloum Djimassal, Joseph Libar, Fernand Kouamé Koffi 8 Sommaire Chapitre 10 La végétation pastorale du lac Fitri. État des lieux et dynamique. 189 Ali Brahim Béchir, Koussou Mian-Oudanang, Alhassine Mahamat, Tchoudiba Bourdjolbo Partie 3 Gouvernance des territoires, logiques sociales et hétérogénéité des acteurs .................................... 203 Introduction ........................................................... 205 Christine Raimond, Florence Sylvestre, Dangbet Zakinet Chapitre 11 Évolution technologique et gestion d’un espace halieutique dans la cuvette nord du lac Tchad ................................... 209 Hadiza Kiari Fougou, Jacques Lemoalle Chapitre 12 De l’insécurité de Boko Haram au conflit intercommunautaire dans le lac Tchad. Le conflit Peul/Boudouma au Niger ................................. 225 Mahamadou Abdourahamani, Maman Waziri Mato Chapitre 13 Pratiques et enjeux de la sécurisation foncière autour du lac Fitri ..................................................... 239 Audrey Mbagogo Koumbraït Chapitre 14 Économie des échanges au lac Fitri. Un déficit récurrent en produits alimentaires ...................... 253 Blaise Bémadji, Ngaressem Goltob Mbaye Chapitre 15 Les territoires d’eau ou comment gérer les ressources halieutiques dans les espaces lacustres ? Les lacs Fitri et Iro ...................................................
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