Oyama, S. 2015. Land degradation and ecological knowledge-based land rehabilitation: Hausa farmers and Fulbe herders in the Sahel region, West Africa. In Reuter, T. ed. Averting a Global Environmental Collapse: The Role of Anthropology and Local Knowledge. Cambridge Scholars Publishing. 165-185.

Oyama, S. 2015. Countering popular beliefs: Urban waste and livestock-induced land rehabilitation in Sahel region of West Africa. The 25th Annual Meeting of the Japan Society of Tropical Ecology (JASTE25) in Kyoto. Inamori Memorial Hall, Kyoto University, Kyoto. 20 June 2015.

Oyama, S. 2015. Reverse Thinking and Action Research. SGAS (Swiss Society for African Studies)-SAGUF (Swiss Academic Society for Environmental Research and Ecology) Conference for Participatory and Integrative Approaches in Researching African Environments: Opportunities, Challenges, Actualities in Natural and Social Sciences. Institute of Social Anthropology, University of Berne, Berne. 23 October 2015.

Oyama, S. 2015. A networking scheme for community-based land rehabilitation and conflict prevention in Niamey and Dogondoutchi. Séminaire du JICA, Académie des Arts Martiaux, Niamey. 24 November 2015.

Oyama, S. 2015. Urban Waste-induced Land Rehabilitation for Food Security and Conflict Prevention in Niger. Séminaire du PNUD (Programme des Nations Unies pour le développement : UNDP), UNDP Niamey office, Niamey. 4 December 2015.