Restoration Contributes to Maintain Ecosystem Services and Bio-Cultural Linkages Between Wetlands and Local Communities: a Case from a Botanical Diversity Hotspot in Japan

Abstract

The Circum-Ise Bay region in central Japan is characterized by a high concentration of species-rich seepage wetlands that provide various ecosystem services to local communities. However, the non-native conifers Cryptomeria japonica and Chamaecyparis obtusa have been widely introduced to the wetlands and compete with native plants. Here, we report the results of a 4-year restoration experiment that involved removing the conifers from a seepage wetland and observing the effects on plant composition, diversity, and ecosystem services to local communities. The experiment was conducted at a seepage wetland in Nakatsugawa city, Japan. The wetland includes many threatened and endemic plants but is also dominated by the conifers. We established three experimental plots within the wetland and removed the conifers from two of them. The stem density of overstory (i.e., canopy-tree) and understory (i.e., sub-canopy to shrub) layers in the conifer-removal plots decreased by 50% while simultaneously increasing the proportion of threatened woody plants by 14.3–50.0%. Despite these changes, plant species diversity in the groundcover layer remained high, and threatened and culturally important species became more concentrated on removal plots than on the control. We did not observe any negative regime shift, such as the establishment of introduced species. The restoration appeared to promote the occurrence of plants associated with bio-cultural linkages between the seepage wetland and local communities and that supply multiple ecosystem services.