Effects of stone-walled terracing and historical forest disturbances on revegetation processes after the abandonment of mountain slope uses on the Yura Peninsula, southwestern Japan

Abandonment of traditional land uses has become an ecosystem management concern in many agricultural landscapes. In this study, we investigated the reforested vegetation about half a century after the abandonment of mountain slopes used for terraced fields and wood production on the Yura Peninsula, Ehime Prefecture, southwestern Japan. Multivariate analyses of species composition indicated that, although many endozoochorous evergreen trees were common on the mountain slopes, fern species adapted to inhabiting the stone-wall structures (e.g., Cyrtomium falcatum, Microlepia strigosa, and Asplenium incisum) and common weed species of arable land occurred significantly more frequently in former stone-walled terraced fields than in former unwalled terraced fields and secondary forests. Tree layer composition was influenced by the forest area around the abandoned terraced fields. Moreover, historically less disturbed forests in the southwestern part of the peninsula were core habitats for regionally rare species, such as Jasminanthes mucronata, Firmiana simplex, and Ardisia sieboldii, and some of those species became established within neighboring abandoned terraced fields. These results indicate that land-use legacies, especially stone-walled terracing and historical forest disturbances, influence the revegetation processes of abandoned mountain slopes in warm-temperate coastal areas.