Patch implications in the maintenance of species richness in an isolated forest site Original Research Article

Plant species richness as a function of patchiness of three different management types, viz. clear-felled, selective-cut and protected, was evaluated in an abandoned urban forest in central Japan. One-hundred and thirty-seven vascular species were recorded at the understory in this 3.2 ha planted forest stand of indigenous conifer — Cryptomeria japonica and Chamaecyparis obtusa. These species included 52.5% herb, 13.9% climber, 15.3% shrub and 18.2% tree species. This species diversity was sustained by dynamic attributes of the patches which were generated and modified by disturbances originating from human activities and natural processes. Past management practices contributed largely to the variation of canopy openings, and continued human activities such as trampling added heterogeneity by soil compaction. These anthropogenic and natural disturbances interacted to effect the pattern of plant species diversity and composition.