海南岛岸礁澄黄滨珊瑚(Porites lutea)集合种群的遗传结构和连通性  

The genetic structure and connectivity of Porites lutea metapopulation of the fringing reefs around the Hainan Island

作　　者：付成冲 李福宇 陈丹丹 侯敬 王珺[1] 李元超 王道儒 王嫣[1] FU Chengchong;LI Fuyu;CHEN Dandan;HOU Jing;WANG Jun;LI Yuanchao;WANG Daoru;WANG Yan(College of Marine Sciences,Hainan University,Haikou 570228,China;Hainan Academy of Ocean and Fisheries Sciences,Haikou 571199,China)

机构地区：[1]海南大学海洋学院,海南海口570228 [2]海南省海洋与渔业科学院,海南海口571199

出　　处：《热带海洋学报》2023年第2期64-77,共14页Journal of Tropical Oceanography

基　　金：国家自然科学基金项目(41376174);海南省重点研发计划项目(ZDYF2018108);国家重点研发计划项目(2018YFC1406504)。

摘　　要：海南岛岸礁的造礁珊瑚代表性种类澄黄滨珊瑚(Porites lutea)是环境适应性较强的块状产卵型珊瑚。探究其遗传结构和连通性将有助于揭示其海南岛岸礁集合种群的遗传多样性格局和幼虫迁移路径,进而阐明海南珊瑚礁的恢复潜力。文章通过11个P.lutea微卫星标记来分析10个海南岛岸礁地理群体(八所、海尾、大铲礁、邻昌礁、雷公岛、木栏头、铜鼓岭、龙湾、大洲岛和鹿回头)和1个西沙群岛(西沙七连屿)群体的遗传结构。结果显示,整体上各群体的遗传多样性中等偏低,平均等位基因丰度(allelic richness,R_(s))为(2.8±1.3)(八所群体)~(3.7±1.7)(邻昌礁群体),平均观测杂合度和期望杂合度分别为0.31(铜鼓岭群体)~0.54(大铲礁群体)和0.50(雷公岛群体)~0.64(海尾群体)。除海南岛东部龙湾群体、大洲岛群体和西部的八所群体、大铲礁群体之外,其他7/11的地理群体均呈杂合子缺失。海南岛岸礁澄黄滨珊瑚P.lutea地理群体间的遗传分化显示,集合种群分为北东南遗传连通带和西岸两支,支间遗传分化显著,前者包括北岸的雷公岛群体和木栏头群体、东岸的大洲岛群体,以及南岸的鹿回头和八所群体。由于珊瑚幼虫随海流迁移而形成的有效的基因流,消弭了它们之间的遗传分化,而西岸群体因北部湾沿岸海流交换不畅,与外部的基因交流受阻。西岸的海尾群体与西南部的八所群体间尽管相距不足50km,但遗传分化明显,这可能是由于昌化江径流形成的盐度波动和悬浮沉积物的隔离作用。同样,铜鼓岭群体因处于铜鼓岭岬角内波影区,其南部八门湾径流或限制了它与东岸群体的基因交流,因而呈现近交、低杂合度和非随机交配特性。此外,由于对离岸礁坡环境的趋同适应,东岸龙湾群体与西岸的离岸岛礁邻昌礁群体、大铲礁群体和海尾群体之间的遗传相似性更高。以P.lutea集合种群为代表的�Porites lutea,the representative species of reef building corals around the Hainan Island,is a spawning,massive coral with strong environmental adaptability.Exploring the genetic structure and connectivity of this species helps to reveal the genetic diversity pattern and larval migration path of coral metapopulation around the Hainan Island,thus clarifying the recovery potential of coral reefs.In this study,11 P.lutea microsatellite markers were screened to analyze the genetic structure of 10 populations of the Hainan fringing reefs and 1 population(XsR)in the Xisha Islands.The results showed that,overall the genetic diversity of all populations was medium to low,with the average allelic richness R_(s) ranging from 2.8±1.3(Basuo population,Bs)to 3.7±1.7(Linchang Reef population,LcR),and the average observed and expected heterozygosity ranged from 0.31(Tongguling population,Tgl)to 0.54(Dachan Reef population,DcR)and 0.50(Leigong Island population,LgI)to 0.64(Haiwei population,Hw),respectively.Except for the Longwan Reef population(LwR)and the Dazhou Island population(DzI),which located in the east of the Hainan Island,and the Basuo population(Bs)and the Dachan Reef population DcR(in the west of Hainan Island),all other populations(7/11)showed evidence of heterozygote deficiency.According to genetic differentiation,the Hainan Island populations were divided into two groups:the north-south-east genetically connected zone and the west coast,and the differentiation between the two branches(AMOVA,0.092)was significant.The former group included Bs,Luhuitou population(Lht),DzI,LgI and Mulantou population(Mlt),due to the significant gene flow created by exchange of ocean currents,there was no obvious genetic differentiation among these five coastal populations,whereas the gene flow of the offshore populations(LcR,DcR and Hw)of the west coast was blocked due to the discontinuity of coastal reefs and slow coastal currents.LwR in the east coast also converges to the west branch,which may be due to the isolation by environm

关 键 词：澄黄滨珊瑚 遗传连通性 微卫星标记 径流 岸礁结构 海流 

分 类 号：P735.542[天文地球—海洋生物学]