Development of restoration and conservation technique for the disturbed island ecosystem in the Ryukyu Archipelago

本文讨论了琉球群岛岛屿生态系统的动态和管理，并提出了修复方法。与冲绳那霸的亚热带研究所合作进行了珊瑚礁研究，并提出了珊瑚礁管理的想法，强调仔细考虑珊瑚、产卵者和孵卵者的繁殖方式。育雏鱼在不同的地区建立了当地的巢穴，但在产卵地，不同地点之间的基因交换预计会更频繁。微环境影响了高温扰动后珊瑚的成活率。来自陆地和河流等生态系统的有机物质是红树林区潮滩底栖动物的重要食物，但来自河流系统的碎屑可能贡献很大。在红树林分解的树叶上生长的细菌菌群是红树林生态系统的重要食物来源。冲绳常绿阔叶林以三叶栲为主，与其他不含三叶槠的顶极林共生。由于后者具有物种多样性高、稀有物种多的特点，受到各种干扰，面积减少，对其恢复进行了探讨。猫鼬和野猫的适宜生境已被发现，但人为干扰对它们的生境和行为有不同的影响。对岛屿生态系统的管理和恢复得到了理论和科学的证实，即保持高度的物种多样性和对未受干扰的生态系统的选择性管理和保护尤为重要。

Dynamics and management of island ecosystem in the Ryukyu Archipelago which had been disturbed in various ways, e.g. inflow of huge amount of red day into shore ecosystems, were discussed and methods for its restoration were proposed. Research on coral reefs was conducted in cooperation with Research Institute for Subtropics in Naha, Okinawa and proposed an idea for the management of coral reef emphasizing the careful thought of reproductive modes of corals, spawners and brooders. Brooders established local demes in different areas, but gene exchange among sites was expected to be more frequent in spawners. Microenvironment affected the survival rates of corals after the disturbance by high temperature. Organic materials supplied from terretrial and river ecosystems, and so on are important for benthic animals on tidal flat as their foods in mangrove areas, but detritus carried from river system may contribute a lot. Bacterial flora developing on decomposing mangrove leaves is important food source in mangrove ecosystems.In Okinawa, evergreen broad-leaved forests dominated by Castanopsis sieboldii occur together with other climax forest without C. sieboldii. Since various disturbance affected in the latter forest, which is characterized by high species diversity and occurrence of rare species, and its area decreased, its restoration was discussed. Suitable habitats were detected for mongooses and wild cats, but anthropogenic disturbance affected their habitat and behavior in various ways.Theoretical and scientific confirmation were obtained for the management and restoration of island ecosystems, i.e. maintenance of high species diversity and selective management and conservation for undisturbed ecosystems are especially important.