2012 Volume 2 Pages 15-26
Paddy fields occupy the widest area among Japanese cultivated lands. They are also the most widely distributed wetlands in Japan. In hilly and mountainous areas, traditional terraced paddy fields are still distributed throughout the country. The small terraces on steep slopes are inconvenient for modern agriculture. Depopulation in rural areas has caused difficulty for labor-intensive cultivation. Therefore abandoned terraces continue to increase nationwide. Recently, the multifunctionality of terraces, including the beauty of landscapes, conservation of land, water resources, and biodiversity was recognized, and re-cultivation of terraces started in various places. As case studies of restoration of terraced paddy fields, we report projects from two areas, Ishibu and Kurasawa, in Shizuoka Prefecture, central Japan. The terraced paddy fields in both areas had been cultivated until the 1960s, but abandonment increased afterwards. In 1999, terrace restoration began in both areas. Local people and volunteers cooperated in the restoration work, and are cooperating in terrace maintenance and cultivation. We confirmed diverse fauna and flora characteristics of paddy fields there. In Kurasawa, we conducted a seed bank survey of an abandoned field dominated by Phragmites australis, and confirmed the existence of diverse seed banks including many characteristic species of cultivated paddy fields. Our results show the potential of restoration of former paddy field flora by seed banks.