| 要旨トップ | 本企画の概要 | | 日本生態学会第73回全国大会 (2026年3月、京都) 講演要旨 ESJ73 Abstract

シンポジウム S07-8 （Presentation in Symposium）

#### Reconsidering the value of the burning forest: ethnobiological perspectives from local communities in Madagascar【E】

*Hiroki SATO（Kyoto Univ.）, Vonjy Ny Aina ANDRIANANTENAINA（Kyoto Univ., Univ. Antananarivo）, Befitia ANDRIANONY（Univ. Antananarivo）, OKAWA RYUNOSUKE（Kyoto Univ.）, Tojotanjona Patrick RAZANAPARANY（Univ. Antananarivo）, Yutaro FUJIMOTO（Kyoto Univ., FFPRI）, Ando Harilalao RAKOTOMAMONJY（Kyoto Univ.）, Takayuki KANEKO（Kyoto Univ.）, Zo Lalaina RAZAFIARISON（Univ. Antananarivo）, Kaoru KITAJIMA（Kyoto Univ.）

The unique biodiversity and ecosystems in Ankafarantsika National Park and the surrounding areas in northwestern Madagascar cannot be conserved without strategies that consider local stakeholders. Since the park’s establishment nearly a century ago, local people who combine rice paddy farming with livestock husbandry have been allowed to reside within the park boundaries and to use natural resources in the designated community forest for each village. However, population growth, partly driven by immigration from other regions, has increased fire pressure, leading to destruction of natural forests, degrading various ecosystem services provided by forests, and threatening the forest resource sustainability. This presentation considers the forest ecosystem services from an ethnobiological perspective with the goal to explore management strategies that enable sustainable forest resource use. Using a photographic guide of 158 woody plant species identified within a 15-ha forest dynamics plot, we interviewed 20 knowledgeable residents from three villages within the park about the uses of these species. A total of 223 use categories and 3,689 use reports were recorded, indicating that 98.7% (156 species) of these plants have at least one reported use. Based on these data, we calculated the use-value index for each species and analyzed its relationship with resource abundance, tree size, and IUCN Red List extinction risk. For destructive uses such as timber extraction for construction and tool production, species with greater abundance and larger size exhibited higher use values. These included several endangered species as well as non-threatened species with substitutable functions. For medicinal and social uses, high use values were concentrated in a limited number of species, which showed low functional substitutability. We summarized the results as a bipartite network linking plant species and use categories, and simulated resource depletion under destructive harvesting scenarios. The results indicate that prioritizing protection of the top 20–30 species with high multi-purpose use most effectively maintains the overall functional value of forest resources. Our ethnobotanical evaluation, in combination with plant ecological data on resource abundance, indicates that the dry forest of Ankarafantsika constitutes a rich repository of useful plant resources for local communities. Developing management strategies that account not only for biodiversity conservation but also for the social needs of local communities will be key to sustaining these seasonally dry forests.

日本生態学会