Study on the maintenance system and conservation of the island ecosystem of Iriomote National Park

本项目旨在对日本琉球群岛伊洛莫特岛的岛屿生态系统进行全面调查，并探讨岛屿生态系统的总体管理程序。本研究首先对该岛生态系统的关键物种伊里奥莫特猫进行了研究，其次对其低营养水平的动植物群落和环境因子进行了研究，最后对包括人工影响在内的生境条件进行了评价。利用地理信息系统（GIS）数据，获取了野猫的野外生态学资料，重点分析了野猫的活动范围、生境利用和活动模式，并分析了影响野猫活动的生物和非生物因素。此外，我们还将结果与同为野猫岛种的对马豹进行了比较。分析了与该地区野猫生态密切相关的三个因素：两栖类动物的丰度和多样性、土地开发和交通事故的发生。对该岛的动植物区系进行了分类和生物地理调查。特别对东南亚地区的爬行动物和植物种类进行了详细的分析。我们对野猫和海蟾蜍这两种被认为对本岛动物有较大影响的入侵物种的情况和影响进行了研究。在此基础上，对伊里奥莫特岛濒临灭绝的伊里奥莫特猫及其生态系统的保护进行了探讨。本项目阐明了该地区陆生动植物区系的特点及影响因素。未来的调查需要详细分析，以了解Iriomote生态系统。

This project aims to conduct the inclusive surveys and to discuss the total management procedure of island ecosystem of the Iriomote Island, in Ryukyu Archipelago, Japan. The study focused first on the Iriomote cat as the key species of this island ecosystem, secondly on the fauna and flora at the lower trophic level in community and environmental factors, and thirdly on the assessment of habitat condition including the artificial effects.1.We obtained the field data on the ecology of the Iriomote cat, especially home range, habitat utilization and movement pattern, partly using the GIS data, and analyzed the affecting biological and non-biological factors. Furthermore, we compared the results with those of the Tsushima leopard cat, which was also the insular species of wild felid.2.We analyzed the three factors closely relating to the ecology of Iriomote cats, abundance and diversity of Amphibia, land development and occurrence of traffic accidents.3.Taxonomical and biogeographical surveys were conducted on fauna and flora of this island. Especially, detailed analysis were done on reptiles and plant species together with South-eastern Asia samples.4.We conducted the situation and effects by two invasive species those were considered to have a strong impact on fauna of this island, feral cat and marine toad.Based on these results, we discussed the conservation of the endangered Iriomote cat and ecosystem of Iriomote Island. The situation and affecting factors of Iriomote cats and characteristics of terrestrial fauna and flora of this area were clarified in this project. Future surveys on the detailed analysis should be needed to understand the Iriomote ecosystem.