Garrison Cody E, Roozbehi Sara, Mitra Siddhartha, Corbett D Reide, Field Erin K
Department of Biology, East Carolina University, Greenville, NC, United States.
Department of Geological Sciences, East Carolina University, Greenville, NC, United States.
Front Microbiol. 2022 Jun 9;13:816573. doi: 10.3389/fmicb.2022.816573. eCollection 2022.
Hurricane frequencies and intensities are expected to increase under warming climate scenarios, increasing potential to disrupt microbial communities from steady-state conditions and alter ecosystem function. This study shows the impact of hurricane season on microbial community dynamics within the barrier island system of Outer Banks, North Carolina. We found that the passage of two sequential energetic hurricanes in 2018 (Florence and Michael) were correlated with shifts in total and active (DNA and RNA) portions of bacterial communities but not in archaeal communities, and within surface waters but not within the sediment. These microbial community shifts were distinct from non-hurricane season conditions, suggesting significant implications for nutrient cycling in nearshore and offshore environments. Hurricane-influenced marine sites in the coastal North Atlantic region had lower microbial community evenness and Shannon diversity, in addition to increased relative abundance of copiotrophic microbes compared to non-hurricane conditions. The abundance of functional genes associated with carbon and nitrogen cycling pathways were also correlated with the storm season, potentially shifting microbial communities at offshore sites from autotroph-dominated to heterotroph-dominated and leading to impacts on local carbon budgets. Understanding the geographic- and system-dependent responses of coastal microbial communities to extreme storm disturbances is critical for predicting impacts to nutrient cycling and ecosystem stability in current and future climate scenarios.
在气候变暖的情景下，飓风的频率和强度预计将会增加，这将增加破坏微生物群落稳态条件并改变生态系统功能的可能性。本研究展示了飓风季节对北卡罗来纳州外滩障壁岛系统内微生物群落动态的影响。我们发现，2018年两场连续的强飓风（佛罗伦萨和迈克尔）的过境与细菌群落的总量和活性（DNA和RNA）部分的变化相关，但与古菌群落无关，且发生在地表水而非沉积物中。这些微生物群落的变化与非飓风季节的情况不同，这表明对近岸和近海环境中的养分循环具有重大影响。与非飓风条件相比，受飓风影响的北大西洋沿岸地区的海洋站点微生物群落均匀度和香农多样性较低，此外富营养微生物的相对丰度也有所增加。与碳和氮循环途径相关的功能基因的丰度也与风暴季节相关，这可能会使近海站点的微生物群落从以自养生物为主转变为以异养生物为主，并对当地碳预算产生影响。了解沿海微生物群落对极端风暴干扰的地理和系统依赖性响应对于预测当前和未来气候情景下对养分循环和生态系统稳定性的影响至关重要。
