2017 Volume 22 Issue 1 Pages 11-32
The procedure of biodiversity-oriented vegetation planning was discussed in Oku-Daisen in Daisen-Oki National Park as a case study. First, we reviewed the current zoning system based on natural park laws and pointed out the following issues: (1) concept of the natural environment, which consists of an excellent landscape, is not clearly defined; therefore, high-biodiversity landscapes are not always zoned as strictly protected areas; (2) conservation of secondary forests/grasslands are not well considered; and (3) the “three types of special protection areas” might be an obstacle for nature restoration in forestry. Then, we used multi-evaluation methods for biodiversity-oriented vegetation planning. Specifically, we used an actual vegetation map (1/5,000), changes in land cover maps from the Meiji to Heisei eras, and distribution map of rare plant species as the fundamental data. Based on them, we made four thematic maps, vegetation naturalness, land cover history reading from aerial photographs of four different ages, the time-based level for vegetation recovery, and rare plant species hotspots and used to evaluate the natural environment and carry out vegetation planning. Comparison of the current zoning map and the vegetation plan clearly demonstrated (1) mismatch between vegetation naturalness and zoning; (2) even though secondary grasslands and marshes were rare species hotspots, their appropriate vegetation management was not considered; (3) it is not clear that the present forestry site will be restored to another vegetation or regenerated again as artificial forest. Most of the previous studies used only vegetation naturalness for evaluate the natural environment. Therefore, the zoning plans suggested by the previous studies did not consider species diversity and required ages for vegetation recovery. However, the vegetation plan presented in this study suggested appropriate approaches for vegetation management of secondary forests and grasslands and nature restoration. Further studies should review the vegetation planning procedure suggested here and its effectiveness.
