An introduction to the Aya Research Site, a Long-Term Ecological Research site, in a warm temperate evergreen broad-leaved forest ecosystem in southwestern Japan: Research topics and design

Abstract

The Aya Research Site (ARS), a long-term ecological research site, was established in 1989 in a warm temperate evergreen broad-leaved forest, southwestern Japan. Distylium racemosum, Persea thunbergii and Quercus spp. predominate in the ARS, together with a few deciduous broad-leaved species. To quantify ecological parameters of tree population and forest dynamics, tree censuses (dbh ≥5 cm) and sapling censuses (dbh <5 cm) were conducted in a 4-ha plot in the ARS. Seedling censuses have also been conducted monthly since 1991. In September 1993, a strong typhoon caused uprootings and stem breakages within the ARS. After the typhoon disturbance, tree densities and basal area decreased and the emergence of pioneer species (e.g., Mallotus japonica, Idesia polycarpa and Zanthoxylum alianthoides) were stimulated beneath canopy gaps. This typhoon is considered to have had a major impact on the forest dynamics in the ARS, and long-term observation is needed to evaluate many basic ecological parameters.