車道による周辺植生への影響(V)

The purpose of the present note is to show how natural forests have been destructed by road construction in natural parks. The subject of the previous reports were chosen cool-temperate broad-leaved deciduous forest, warm-temperate broad-leaved evergreen forest, and subtropical broad-leaved evergreen forest. These forests come under the districts without snow on the Pacific Ocean side. The plant communities in the district with heavy snow on the Sea of Japan side differ in many respects from those on the Pacific Ocean side, especially in the cool-temperate and subalpine zons. In this paper the author tries to analyse the influence of road construction among cool-temperate and subalpine forest on the Sea of Japan side. As the stand of this study, was selected Mt. Tateyama region (Toyama Prefecture), which is designated as Chubusangaku National Park. The antecedent road to Tateyama-Kurobe alpine route was constructed in 1956. Firstly, the author investigated the floristic composition of natural forest and roadside vegetation. Natural forest was classified into seven vegetational units (Table 2) and roadside vegetation into four units (Table 3). These communities are distributed along the park road at the altitude of 1,000 m to 2,000 m. He selected four areas (Fig. 3) including these typical communities, and made vegetation maps on a scale of 1:5,000 (Fig. 4～7). The vegetation maps show the destructed zone caused by road construction. The influenced zone is shown black on the maps. The width of the belt influenced is 10～20 m from the road at the altitude of 1,000～1,200 m, 2～5 m at 1,200～1,500 m, and 5～10 m at 1,600-2,00m. Secondly, he investigated the influence by belt transect method vertically every 100 m from 1,000 to 2,000 m. The result was similar to the former. These results show that the influence of road construction is less in the district with heavy snow than that without snow.Article信州大学農学部紀要 13(1): 63-88(1976)departmental bulletin pape