海南岛淡水蟹类分布格局与多样性保护

热带岛屿生物多样性是全球生物多样性保护研究的热点之一。海南岛是中国面积最大的热带岛屿, 丰富独特的淡水蟹类是维持岛内淡水生态系统功能完整性的关键类群。本文通过多年野外调查, 综合历史及最新文献资料, 对海南岛淡水蟹类物种多样性及其现状进行调查和评估, 并对淡水蟹类物种多样性保护现状进行了分析讨论。研究发现, 海南岛淡水蟹类物种多样性分布中心位于中南部山地, 主要集中于中部的霸王岭、鹦哥岭和猕猴岭, 南部的五指山和吊罗山, 以及西南部的尖峰岭一带。其物种多样性整体上呈现中南部山地高、平原台地低的特点。根据《IUCN物种红色名录濒危等级和标准》对海南岛淡水蟹类物种现状的评估结果显示, 全岛受威胁淡水蟹类物种的占比为16.7%。基于分布区预测, 以海南热带雨林国家公园为主体的保护地对淡水蟹类潜在适宜分布区的覆盖度明显优于此前碎片化的各级保护区。本文研究结果显示, 海南岛淡水蟹类的总体生存状况良好, 但一部分山地或平原种类处于受胁状态。国家公园体制的建立有望为岛内淡水蟹类物种多样性保护提供前所未有的机遇。基于物种多样性分布格局开展淡水蟹类等淡水生物多样性监测, 有助于促进海南岛淡水生态系统完整性的长效保护与可持续发展。

The distribution pattern and biodiversity conservation of freshwater crabs in Hainan Island

Aims: The biodiversity of tropical islands is a popular topic in global biodiversity conservation research. Hainan Island is the largest tropical island in China. Freshwater crabs are a keystone species for freshwater ecosystems in Hainan Island. The aims of this study were thus to identify the distribution pattern and assess the threat status of freshwater crabs in Hainan Island.Methods: In this study, we used field surveys and conducted a literature review to investigate the species diversity and conservation status for freshwater crabs in Hainan.Results: Our results indicate that the diversity hotspots for freshwater crab species on Hainan Island are located in the south-central mountainous area (especially Bawangling, Yinggeling, Mihouling, Wuzhi Mountain, Diaoluo Mountain and Jianfengling). Freshwater crab diversity is higher in the central and southern mountains and lower in the plains. According to the IUCN Red List Categories and Criteria, 16.7% of freshwater crab species on Hainan Island are threatened. Diversity conservation effectiveness analyses demonstrate that the Hainan Tropical Rainforest National Park system as leading part of Hainan’s protected area system is better than the previous system (which was several fragmented nature reserves) for covering the potential distribution areas of freshwater crabs. Overall, conservation status for freshwater crabs in Hainan Island is favorable, but some species are threatened.Conclusion: The establishment of the national park system is expected to provide unprecedented opportunities for the conservation of freshwater crab species diversity in Hainan Island. Monitoring freshwater biological diversity based on the distribution pattern of species diversity will promote the long-term protection and sustainable development for freshwater ecosystems on Hainan Island.