Distribution of Bamboo Stands and Its Topographical Conditions in Nagano Prefecture, Central Japan

Abstract

In recent years, range expansion of bamboo stands has become a problem in Japan. In order to plan an appropriate management for bamboo stands, it is necessary to understand the topographical conditions controlling their establishment. Although previous studies have evaluated the topographical conditions in a limited area, no studies have been evaluated topographical conditions of bamboo stands under their climatic potential habitat in wide range. The purpose of this study was to obtain detailed information on the distributions of bamboo stands in Nagano Prefecture by using aerial photographs and field surveys, to evaluate the topographical conditions of bamboo stands in comparison with that of potential habitats. As a result, 55.7 percent of all bamboo stands in Nagano Prefecture (10,523 sites, total area of 1,449.0 ha) were located on gentle slopes with slope aspects of 5-20 degrees, and 53.5 percent were located on slopes facing southeast, south, and southwest, whereas potential habitat of bamboo stands in Nagano Prefecture has two peaks at around 0°and 30°, and is distributed in all directions. Moreover, these topographical conditions of bamboo stands were common among the five regions of the prefecture. These results imply that bamboo stands in Nagano Prefecture tended to locate mostly on gentle south-facing slopes and suggesting that local residents have been planted and remain in the present topographical conditions from the viewpoint of land use and bamboo forest management.