2018 年 30 巻 p. 21-35
Many Japanese common forests are underutilized because of the increase in fossil fuel consumption, agricultural machinery, and imported timber. Depopulation in mountainous regions accelerates the underutilization of common forests. In such conditions, allowing nonlocals to use communal forests may benefit local communities. To investigate the social conditions for successful accommodation of nonlocals, we compared the uses and rules of collecting wild vegetables and mushrooms in 10 common forests in Tadami, Fukushima, focusing on the characteristics of social relationships in these communities. In this research, we found that communities could be classified according to two dimensions based on how they dealt with nonlocals wanting to use the common forests. One was the existence of institutions to accommodate nonlocals' entrance, and the other was how actively resources were invested to operate such institutions. We focused on active institutions. Among the 10 communities studied, five had adopted active institutions, such as systems for entrance fees and guides; two communities had adopted inactive institutions (e.g., extensive management); and three communities had adopted no institution for the entrance of nonlocals. As a result, communities adopting active institutions were those with high rates of participation in community meetings and collaborative operations. Members of such communities also had homogeneity in sources of income. If community members share homogeneous income source and have a mutual interest in communal forests, it is easier to engage in collective action. However, our findings indicated that homogeneity alone is not a sufficient condition for realizing collective action.