Topographic factors and logging practices affecting vegetative distribution in the Kuta Research Forest of Kyoto Prefectural University [Japan]

Landscape ecology has recently become recognized as an academic backbone for solving problems in sustainable forest management and conservation of biodiversity. The fundamental task of landscape ecology today is the establishment of "ecotopes", spatial units of landscape classified by environment, which is separated into nonbiological factors (physiotopes) and biological factors (biotopes). In this study, as an application of landscape ecology to forest planning, we examined the effectiveness of a geographic information system (GIS) as a spatial analytical tool for forest landscape management. We overlaid physiotopes by means of the GIS, and compared the vegetation in each in order to assess how physiotopes affected the vegetative distribution (biotopes) in our study area. We created two thematic maps of non-biological factors topographic factors (elevation, aspect, and hydrology) and degree of human impact (impact of logging)-with the GIS. We used Shannon-Wiener's diversity index to examine any effects of physical environment on vegetative distribution in order to verify differences in biodiversity of biotopes (vegetative distribution) in the same or different physiotopes (topographic factors and human impact). We also compared the vegetative composition of each physiotope by the use of vegetative data. The differences in understory species diversity in the physiotopes were significant when Shannon-Wiener's diversity index was calculated from number of individuals, and diversity of overstory species was represented well when the index was calculated from basal area. Among different terrain shapes, differences in vegetative diversity were observed in understory but not overstory vegetation. Also, the vegetative diversity of a site in the early phase of recovery was significantly different from the diversity in a mature forest. However, the effect of logging on vegetative diversity was not as clear in a maturing forest as in the mature forest.