Dynamique de l’occupation et de la couverture du sol dans le bassin versant d’Ankavia, Antalaha, Nord-Est de Madagascar
Abstract
Un diagnostic environnemental en vue d’une gestion intégrée des ressources en eau dans le bassin versant d’Ankavia, District d’Antalaha, Région SAVA a été mené du janvier au juin 2019 afin de (1) suivre l’évolution temporelle d’occupation de trois sous-bassins versants, Ankaviabe, Sahafihitry et Antsahovy entre 1992-2015, (2) déterminer les causes et les conséquences des pressions (et des menaces) qui pèsent sur ces trois sous-bassins et (3) évaluer les forces, les faiblesses et les opportunités pour pouvoir faire face à ces pressions (menaces). La descente sur le terrain combinée aux enquêtes auprès de diverses entités à Antalaha a permis d’arriver à ces points. La réduction de la surface forestière à partir des années 2000-2005 a donné place aux paysages plus anthropogéniques comme Mosaïque de culture et la Mosaïque arborée. La conquête de nouvelle terre pour la riziculture pluviale (Tavy) associée à la croissance démographique galopante et non contrôlée est la principale cause de cette perte forestière. Le passage fréquent des cyclones violents précarise la vie socio-économique des habitants dans ces trois sous-bassins et attarde également la résilience de l’écosystème forestier dans la zone. La proximité de massif forestier Makira qui rend humide le climat dans le bassin versant et la présence d’un projet de recherche et de développement GIRE-SAVA (Gestion Intégrée des Ressources en Eau de la Région SAVA) constituent des forces et d’opportunités permettant de pallier les faiblesses liées à l’insuffisance des données socio-économiques sur la qualité et la quantité de l’eau ainsi qu’à l’insuffisance d’infrastructure d’assainissement et d’hygiène dans ce bassin. Cette analyse de forces/faiblesses/opportunités est essentiel afin d’arriver à une gestion intégrée de ce bassin versant d’Ankavia.
An environmental assessment for integrated water resource management in the Ankavia watershed, Antalaha District, SAVA Region, was conducted from January to June 2019 to (1) monitor the temporal changes in land use of three sub-watersheds, Ankaviabe, Sahafihitry, and Antsahovy between 1992 and 2015, (2) determine the causes and consequences of the pressures (and threats) affecting these three sub-watersheds, and (3) assess the strengths, weaknesses, and opportunities to address these pressures (and threats). Field survey combined with interviews among various entities in Antalaha enabled these objectives to be achieved. The reduction of forest area from 2000 to 2005 onward gave way to more anthropogenic landscapes such as agricultural mosaics and tree mosaics. The acquisition of new land for hill rice cultivation (Tavy) associated with uncontrolled population growth is the main cause of this forest loss. The frequent occurrence of violent cyclones weakens the socio-economic life of the inhabitants in these three sub-basins and also hinders the resilience of the forest ecosystem in the area. The proximity of the Makira forest massif, which creates a humid climate in the watershed, and the presence the GIRE-SAVA research and development project (Integrated Water Resource Management of the SAVA Region) constitute strengths and opportunities that can address the weaknesses related to the lack of socio-economic data on the quality and quantity of water, as well as the inadequacy of sanitation and hygiene infrastructure in this catchment. This strengths/weaknesses/opportunities analysis is essential to achieving integrated management of the Ankavia watershed
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2. Albuquerque, U. P., Nascimento, A. L. B., Soldati, G. T., Feitosa, I. S., Campos, J. L. A., Hurrell, J. A., Hanazaki, N., de Medeiros, P. M., da Silva, R. R. V., Ludwinsky, R. H., Júnior, W. S. F. & Reyes-García, V. (2019). Ten important questions/issues for ethnobotanical research. Acta Botanica Brasilica, 33, 376-385.
3. Blakey, R.V., Kingsford, R.T., Law, B.S. & Stoklosa, J. 2017. Floodplain habitat is disproportionately important for bats in a large river basin. Biological Conservation, 215, 1-10.
4. Borgerson, C. (2013). The fitoaty: an unidentified carnivoran species from the Masoala peninsula of Madagascar. Madagascar Conservation & Development, 8: 81-85.
5. Clark, M. (2012). Deforestation in Madagascar: Consequences of Population Growth and Unsustainable Agricultural Processes. Global Majority E-Journal, 3, 61-71.
6. CREAM (2013). Monographie de la Région SAVA. Centre de Recherches, d’Etudes et d’Appui à l’analyse économique à Madagascar https://www.pseau.org/outils/ouvrages/mg_mef_monographie-region-sava_2014.pdf (Téléchargé le 11 septembre 2024).
7. Crutzen, P. J. & Stoermer, E. F. (2000) The “Anthropocene”. IGBP Newsletter, 41, 17–18.
8. Dou, Y., Cosentino, F., Malek, Z., Maiorano, L., Thuiller, W. & Verburg, P. H. (2021). A new European land systems representation accounting for landscape characteristics. Landscape Ecology, 36, 2215-2234.
9. Ellis, E.C., Gauthier, N., Goldewijk, K.K., Bird, R. B., Boivin, N., Díaz, S., Fuller, D. Q., Gill, J. L., Kaplanm, J. O., Kingstonn, N., Lockeo, H., McMichael, C.N.H., Ranco, D., Rick, T. C., Shaws, M. R., Stephens, L., Svenning, J.-C. & Watson, J. E. M. (2021). People have shaped most of terrestrial nature for at least 12,000 years. PNAS, 118 (17): e2023483118.
10. Erwin, K. L. (2009) Wetlands and global climate change: the role of wetland restoration in a changing world. Wetlands Ecology and Management, 17, 71-84. https://doi.org/10.1007/s11273-008-9119-1
11. Evers, M. & Nyberg, L. (2013). Coherence and inconsistency of European instruments for integrated river basin management. International Journal of River Basin Management, 11: 139-152.
12. Farahbakhsh, Bauch, C. T. & Anand, M. (2022). Modelling coupled human–environment complexity for the future of the biosphere: strengths, gaps and promising directions. Phylosophical Transactions of the Royal Society B, 377, 20210382.
13. Filippi, L. (2018). Madagascar : A SAVA, capitale mondiale de la vanille, une épice sous surveillance. https://www.francetvinfo.fr/monde/afrique/economie-africaine/madagascar-a-sava-capitale-mondiale-de-la-vanille-une-epice-sous-surveillance_3056757.html (Téléchargé le 09 septembre 2024).
14. Glaw, F., Köhler, J. & Vences, M. (2011). New Species of Gephyromantis from Marojejy National Park, Northeast Madagascar. Journal of Herpetology, 45, 155-160.
15. Hänke, H., Barkmann, J., Blum, L., Franke, Y., Martin, D. A., Niens, J., Osen, K., Uruena, V., Witherspoon, S. A. & Wurz, A. (2019). Socio-economic, land use and value chain perspectives on vanilla farming in the SAVA region (north-eastern Madagascar): the Diversity Turn Baseline Study (DTBS). Discussion Paper 1806. Department of Agricultural Economics and Rural Development, University of Goettingen, D 37073 Göttingen.
16. Hanson, T., Brooks, T. M., da Fonseca, G. A. B., Hoffmann, M., Lamoreux, J. F., Machlis, G., Mittermeier, C. G., Mittermeier, R. A. & Pilgrim, J. D. (2009). Warfare in Biodiversity Hotspots. Conservation Biology, 23, 578-587.
17. Innes, J. L. (2010). Madagascar rosewood, illegal logging and the tropical timber trade. Madagascar Conservation & Development, 5, 6-10.
18. Jones, J. P. G, Ratsimbazafy, J., Ratsifandrihamanana, A. N., Watson, J. E. M., Andrianandrasana, H. T., Cabeza, M., Cinner, J. E., Goodman, S. M., Hawkins, F., Mittermeier, R. A., Rabearisoa, A. L., Rakotonarivo, O. S., Razafimanahaka, J. H., Razafimpahanana, A. R., Wilmé, L. & Wright, P. C. (2019). Last chance for Madagascar’s biodiversity. Nature Sustainability, 2, 350-352.
19. Krause, B., Culmsee, H., Wesche, K., Bergmeier, E. & Leuschner, C. (2011). Habitat loss of floodplain meadows in north Germany since the 1950s. Biodiversity and Conservation, 20, 2347-2364.
20. Mananjara, L. (2021). Diagnostic environnemental pour une mise en place d’une gestion intégrée des ressources en eau : Cas du bassin versant d’Ankavia, district d’Antalaha, région SAVA, Madagascar. Mémoire de fin d’études pour l’obtention du diplôme de Masters. Parcours : Gestion de la Biodiversité et Protection de l’Ecosystème (GBPE). Faculté des Sciences, Université d’Antsiranana.
21. Moore, M., Razafindrina, K., V., Méndez, V. E. & Niles, M. T. (2024). An analysis of the adoption of the “system of rice intensification” (SRI): why a homegrown technique has yet to take seed among rice farmers in Madagascar. Cogent Food & Agriculture, 10, 2319932.
22. Morelli, T. L., Smith, A. B., Mancini, A. N., Balko, E. A., Borgerson, C., Dolch, R., Farris, Z., Federman, S., Golden, C. D., Holmes, S. M., Irwin, M., Jacobs, R. L., Johnson, S., King, T., Lehman, S. M., Louis Jr, E. E., Murphy, A., Randriahaingo, H. N. T., Randrianarimanana, H. L. L., Ratsimbazafy, J., Razafindratsima, O. H. & Baden, A. L. (2020). The fate of Madagascar’s rainforest habitat. Nature Climate Change, 10, 89–96.
23. Neugarten, R. A., Rasolofoson, R. A., Barrett, C. B., Vieilledent, G. & Rodewald, A. D. (2024). The effect of a political crisis on performance of community forests and protected areas in Madagascar. Nature Communications, 15, 2963.
24. Ordway, E. M. (2015). Political shifts and changing forests: Effects of armed conflict on forest conservation in Rwanda. Global Ecology and Conservation, 3, 448–460.
25. Patel, E. R. (2014). Silky sifaka Propithecus candidus Grandidier, 1871 Madagascar (2000, 2002, 2004, 2006, 2008, 2010, 2012). In C. Schwitzer, R. A. Mittermeier, A. B. Rylands, et al. (eds.), Primates in Peril: The World’s 25 Most Endangered Primates 2012-2014 (pp 38–43). Primate Specialist Group, International Primatological Society, Arlington and Conservation International IUCN/SSC.
26. Paudyal, K., Baral, H., Putzel, L., Bhandari, S. & Keenan, R. J. (2017). Change in land use and ecosystem services delivery from community-based forest landscape restoration in the Phewa Lake watershed, Nepal. International Forestry Review, 19, 88–101.
27. Posthumus, H., Rouquette, J.R., Morris, J., Gowing, D.J.G. & Hess, T.M. (2010). A framework for the assessment of ecosystem goods and services; a case study on lowland floodplains in England. Ecological Economics, 69 (7), 1510-1523.
28. Rajib, A., Zheng, Q., Lane, C. R., Golden, H. E., Christensen, J. R., Isibor, I. I. & Johnson, K. (2023). Human alterations of the global floodplains 1992–2019. Scientific Data, 10, 449.
29. Rakotoarimanana, Z. M. H., Rakotoarimanana, Z. H., Pandin, M. G. R. & Waloejo, C. S. (2022). Analysis of tropical cyclones 2000-2020 in Madagascar. Disaster Advances, 15, 13-20.
30. Ramahaimandimby, Z., Randriamaherisoa, A., Vanclooster, M. & Bielders, C.L. (2023). Driving factors of the hydrological response of a tropical watershed: The Ankavia River Basin in Madagascar. Water, 15, 2237.
31. Randriamalala, H. & Liu, Z. (2010). Rosewood of Madagascar: Between democracy and conservation. Madagascar Conservation & Development, 5, 11-22.
32. Rimal, B., Baral, H., Stork, N. E., Paudyal, K. & Rijal, S. (2015). Growing city and rapid land use transition: Assessing multiple hazards and risks in the Pokhara valley, Nepal. Land, 4, 957–978. doi:10.3390/land4040957
33. Romain (2023). Oiseau très rare disparu il y a 24 ans redécouvert dans une forêt dense à Madagascar. https://www.netcost-security.fr/science/150087/oiseau-tres-rare-disparu-il-y-a-24-ans-redecouvert-dans-une-foret-dense-a-madagascar/ (Téléchargé le 09 septembre 2024).
34. Rouquette, J.R., Posthumus, H., Morris, J., Hess, T.M., Dawson, Q.L. & Gowing, D.J.G. (2011). Synergies and trade-offs in the management of lowland rural floodplains: an ecosystem services approach. Hydrological Sciences Journal, 56 (8), 1566–1581.
35. Schatz, G. E., Lowry II, P. P. & Ramisamihantanirina, A. (1998). Takhtajania perrieri rediscovered. Nature, 391, 133-134.
36. Scherz, M. D., Köhler, J., Rakotoarison, A., Glaw, F. & Vences, M. (2019). A new dwarf chameleon, genus Brookesia, from the Marojejy massif in northern Madagascar. Zoosystematics and Evolution, 95, 95-106.
37. Schuurman, D. & Lowry II, P. P. (2009). The Madagascar rosewood massacre. Madagascar Conservation & Development, 4, 98-102.
38. Stanley, R. C. & Raxworthy, C.J. (2016). Rediscovery of the Enigmatic Day Gecko Phelsuma masohoala in Northeast Madagascar. Herpetological Conservation and Biology, 11, 402–407.
39. Suzzi-Simmons, A. (2023). Status of deforestation of Madagascar. Global Ecology and Conservation, 42, e02389.
40. Tockner, K. & Stanford, J.A. (2002). Riverine flood plains: present state and future trends. Environmental Conservation, 29, 308–330.
41. Waeber, P. O., Schuurman, D., Ramamonjisoa, B., Langrand, M., Barber, C. V., Innes, J. L., Lowry II, P. P. & Wilmé, L. (2019). Uplisting of Malagasy precious woods critical for their survival. Biological Conservation, 235, 89–92.
42. WCS. (2017). Plan d’Aménagement et de Gestion du Parc Naturel Makira 2017-2021. Wildlife Conservation Society.
43. Williams, B. A., Venter, O., Allan, J. R., Atkinson, S. C., Rehbein, J. A., Ward, M., Marco, M. D., Grantham, H. S., Ervin, J., Goetz, S. J., Hansen, A. J., Jantz, P., Pillay, R., Rodrıguez-Buritica, S., Supples, C., Virnig, A. L. S. & Watson, J. E. M. (2020). Change in terrestrial human footprint drives continued loss of intact ecosystems. One Earth, 3, 371-382.
44. World Population Prospect (2024). United Nations population estimates and projections. Department of Economic and Social Affairs. US.
45. Wurz, A., Tscharntke, T., Martin, D. A., Osen, K., Anjaharinony A. N. A. Rakotomalala, A. A. N. A., Raveloaritiana, E., Andrianisaina, F., Dröge, S., Fulgence, T. R., Soazafy, M. R., Andriafanomezantsoa, R., Andrianarimisa, A., Babarezoto, F. S., Barkmann, J., Hänke, H., Hölscher, D., Kreft, H., Rakouth, B., Guerrero-Ramírez, N. R., Ranarijaona, H. L. T., Randriamanantena, R., Ratsoavina, F. M., Lala Harivelo Raveloson Ravaomanarivo, L. H. R. & Grass, I. (2022). Win-win opportunities combining high yields with high multi-taxa biodiversity in tropical agroforestry. Nature Communications, 13, 4127.
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