Quantitative Analysis of Fragmented Landscape Patterns Resulting from Timber Harvesting Practices in Kyoto University Forests

Abstract

Abstract This paper presents the use of a set of spatial statistics to quantify the forest landscape pattern caused by the patchwork of timber harvesting and the subsequent coniferous plantations made over a 60-year period (1921–1981) in the natural forests of Kyoto University Forests. Aerial photography and orthophotography were used to analyze spatial patterns of forest cover changes at patch level between 1974 and 1996. Base maps of forest pattern were digitized in raster format using four dominant forest cover types in the study area The total number of digitized patches for 1974 and 1996 were 435 and 453, respectively. Four groups of indices were employed to quantify landscape heterogeneity and pattern for each of the two years: (1) patch size; (2) patch abundance; (3) patch shape; and (4) patch spacing. Patch abundance and patch spacing measures provided considerable information on major patterns of forest landscape dynamics over time. Patch size and shape indices contributed information on specific characteristics of the individual patches and may be useful for applications designed to study specific interior and edge habitats or for the prescription of forest cutting patterns and/or cutting-unit size. The net loss of forest covers that occurred during 60-year period trends to be balanced primarily by regeneration of areas cut before 1943 and secondarily by plantation of areas cut before 1965.