ABSTRACT: Microorganisms are central to the functioning of coral reef ecosystems, but their dynamics are unstudied on most reefs. We examined the microbial ecology of shallow reefs within the Federated States of Micronesia. We surveyed 20 reefs surrounding 7 islands and atolls (Yap, Woleai, Olimarao, Kosrae, Kapingamarangi, Nukuoro, and Pohnpei), spanning 875053 km². On the reefs, we found consistently higher coral coverage (mean ± SD = 36.9 ± 22.2%; max 77%) compared to macroalgae coverage (15.2 ± 15.5%; max 58%), and low abundances of fish. Reef waters had low inorganic nutrient concentrations and were dominated by Synechococcus, Prochlorococcus, and SAR11 bacteria. The richness of bacterial and archaeal communities was significantly related to interactions between island/atoll and depth. High coral coverage on reefs was linked to higher relative abundances of Flavobacteriaceae, Leisingera, Owenweeksia, Vibrio, and the OM27 clade, as well as other heterotrophic bacterial groups, consistent with communities residing in waters near corals and within coral mucus. Microbial community structure at reef depth was significantly correlated with geographic distance, suggesting that island biogeography influences reef microbial communities. Reefs at Kosrae Island, which hosted the highest coral abundance and diversity, were unique compared to other locations; seawater from Kosrae reefs had the lowest organic carbon (59.8-67.9 µM), highest organic nitrogen (4.5-5.3 µM), and harbored consistent microbial communities (>85% similar), which were dominated by heterotrophic cells. This study suggests that the reef-water microbial ecology on Micronesian reefs is influenced by the density and diversity of corals as well as other biogeographical features.

中文翻译：

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密克罗尼西亚联邦珊瑚为主的礁石的微生物生态学

摘要：微生物是珊瑚礁生态系统功能的核心，但大多数珊瑚礁的动力学尚未得到研究。我们检查了密克罗尼西亚联邦内浅礁的微生物生态。我们调查了围绕7个岛屿和环礁（亚普，沃莱，奥利马拉，科斯雷，Kapingamarangi，努库罗和波纳佩）的20条珊瑚礁，跨度为875053 km ²。在珊瑚礁上，我们发现与巨藻覆盖率（15.2±15.5％；最大58％）相比，珊瑚覆盖率始终较高（平均±SD = 36.9±22.2％；最大77％），并且鱼的丰度较低。珊瑚礁水中的无机养分含量低，主要由Synechococcus，Prochlorococcus和SAR11细菌控制。细菌和古细菌群落的丰富度与岛屿/环礁与深度之间的相互作用显着相关。珊瑚礁的高覆盖率与黄杆菌科，Leisingera，Owenweeksia，弧菌和OM27进化枝以及其他异养细菌群的较高相对丰度有关，这与居住在珊瑚附近和珊瑚黏液内的水域中的群落一致。珊瑚礁深度的微生物群落结构与地理距离显着相关，这表明岛屿的生物地理学会影响珊瑚礁的微生物群落。与其他地区相比，科斯雷岛的珊瑚礁拥有最高的珊瑚丰度和多样性。来自科斯雷礁的海水具有最低的有机碳（59.8-67.9 µM），最高的有机氮（4.5-5.3 µM），并具有始终如一的微生物群落（> 85％相似），其中以异养细胞为主。这项研究表明，密克罗尼西亚礁上的礁水微生物生态学受到珊瑚的密度和多样性以及其他生物地理特征的影响。并拥有一致的微生物群落（> 85％相似），并以异养细胞为主。这项研究表明，密克罗尼西亚礁上的礁水微生物生态学受到珊瑚的密度和多样性以及其他生物地理特征的影响。并拥有一致的微生物群落（> 85％相似），并以异养细胞为主。这项研究表明，密克罗尼西亚礁上的礁水微生物生态学受到珊瑚密度和多样性以及其他生物地理特征的影响。