海坛岛及周边岛屿野生石松类和蕨类植物区系与地理分布研究

通过野外调查和资料整理，对海坛岛及周边24个海岛的石松类和蕨类植物区系组成、分布区类型与生态类型进行调查统计，与不同地区山地石松类和蕨类植物属的分布区类型进行相似性及聚类分析，以期为海坛岛及周边岛屿石松类和蕨类植物资源的合理开发利用提供参考。结果表明：海坛岛及周边岛屿共有石松类和蕨类植物20科37属60种，区系在系统发育上既存在原始的科及进化的科，也存在介于二者之间的科，该地区植物区系起源古老；属以单种属居多，优势科属现象不明显；地理分布以热带分布为主，热带亲缘显著，具有从热带向温带过渡的性质；海坛岛及周边岛屿与纬度相近的大嵛山岛、东山岛具有更高的相似性且关系密切，与纬度较远的山东长岛列岛相似性较低；在地理亲缘关系上，该地区与南亚热带山地距离较近，同时海坛岛及周边岛屿与观音岽自然保护区的联系最为紧密，具有强烈的热带性质特点；生态类型上，该地区石松类和蕨类植物主要以土生、石生为主。此外，海坛岛及周边岛屿分布有国家重点保护植物水蕨（VU，Ⅱ级）、金毛狗（Ⅱ级）和中国特有植物翠云草。本研究结果可以为海坛岛及周边岛屿植物资源的合理利用与保护提供参考依据。

Flora and Geographical Distribution of the Wild Lycophytes and Ferns in Haitan Island and Surrounding Islands

Through field surveys and data compilation, statistical analysis of the lycophytes and ferns floristic composition, distribution area types and ecological types of Haitan Island and the surrounding 24 islands, and compared with the distribution area types in different regions, it is expected to provide a reference for the rational development and utilization of plant resources in Haitan Island and the surrounding islands, the results show that Haitan Island and its surrounding islands share 20 families, 37 genera and 60 species of stone pines and ferns. In the floristic,there are both primitive families and evolutionary families, as well as families in between. The origin of the flora in this area is ancient; Most of the genera are single species, the dominant family genera phenomenon is not obvious; The areal type of the main islands in Haitan Island and the surrounding islands is dominated by tropical distribution, with significant tropical relatives and the transition from tropical to temperate; Haitan Island and its surrounding islands have a higher similarity and close relationship with Dayushan Island and Dongshan Island, which are close in latitude, and have lower similarity with Changdao Islands, which are farther in latitude; In terms of geographical relationship, the region is closer to the south subtropical mountains, while Haitan Island and surrounding islands are the most closely connected with the Guanyintong Nature Reserve, which has a strong tropical character; In terms of ecological type, the lycophytes and ferns in this area are mainly soil and stone. Besides, Haitan Island and its surrounding islands are home to Ceratopteris thalictroides(VU, level Ⅱ), Cibotium barometz(level Ⅱ), and endemic species to China Selaginella uncinata. The research results can provide a theoretical basis for rational utilization and protection of the plant in Haitan Island and its surrounding islands.