Dang Hongyue, Chen Chen-Tung A
State Key Laboratory of Marine Environmental Science, Institute of Marine Microbes and Ecospheres, College of Ocean and Earth Sciences, Xiamen UniversityXiamen, China.
Department of Oceanography, National Sun Yat-sen UniversityKaohsiung, Taiwan.
Front Microbiol. 2017 Jul 14;8:1246. doi: 10.3389/fmicb.2017.01246. eCollection 2017.
Transformation and mobilization of bioessential elements in the biosphere, lithosphere, atmosphere, and hydrosphere constitute the Earth's biogeochemical cycles, which are driven mainly by microorganisms through their energy and material metabolic processes. Without microbial energy harvesting from sources of light and inorganic chemical bonds for autotrophic fixation of inorganic carbon, there would not be sustainable ecosystems in the vast ocean. Although ecological energetics (eco-energetics) has been emphasized as a core aspect of ecosystem analyses and microorganisms largely control the flow of matter and energy in marine ecosystems, marine microbial communities are rarely studied from the eco-energetic perspective. The diverse bioenergetic pathways and eco-energetic strategies of the microorganisms are essentially the outcome of biosphere-geosphere interactions over evolutionary times. The biogeochemical cycles are intimately interconnected with energy fluxes across the biosphere and the capacity of the ocean to fix inorganic carbon is generally constrained by the availability of nutrients and energy. The understanding of how microbial eco-energetic processes influence the structure and function of marine ecosystems and how they interact with the changing environment is thus fundamental to a mechanistic and predictive understanding of the marine carbon and nitrogen cycles and the trends in global change. By using major groups of chemolithoautotrophic microorganisms that participate in the marine nitrogen cycle as examples, this article examines their eco-energetic strategies, contributions to carbon cycling, and putative responses to and impacts on the various global change processes associated with global warming, ocean acidification, eutrophication, deoxygenation, and pollution. We conclude that knowledge gaps remain despite decades of tremendous research efforts. The advent of new techniques may bring the dawn to scientific breakthroughs that necessitate the multidisciplinary combination of eco-energetic, biogeochemical and "omics" studies in this field.
生物必需元素在生物圈、岩石圈、大气圈和水圈中的转化与迁移构成了地球的生物地球化学循环，这些循环主要由微生物通过其能量和物质代谢过程驱动。如果没有微生物从光和无机化学键中获取能量来进行无机碳的自养固定，广阔的海洋中就不会有可持续的生态系统。尽管生态能量学（生态 energetics）已被强调为生态系统分析的核心方面，且微生物在很大程度上控制着海洋生态系统中的物质和能量流动，但从生态能量学角度对海洋微生物群落的研究却很少。微生物多样的生物能量途径和生态能量策略本质上是进化时间内生物圈 - 地球圈相互作用的结果。生物地球化学循环与整个生物圈的能量通量紧密相连，海洋固定无机碳的能力通常受到营养物质和能量可用性的限制。因此，了解微生物生态能量过程如何影响海洋生态系统的结构和功能，以及它们如何与不断变化的环境相互作用，对于从机制和预测角度理解海洋碳氮循环以及全球变化趋势至关重要。本文以参与海洋氮循环的主要化学自养微生物群体为例，研究了它们的生态能量策略、对碳循环的贡献以及对与全球变暖、海洋酸化、富营养化、脱氧和污染相关的各种全球变化过程的假定响应和影响。我们得出结论，尽管经过了数十年的巨大研究努力，知识空白仍然存在。新技术的出现可能会为科学突破带来曙光，而这需要在该领域将生态能量学、生物地球化学和“组学”研究进行多学科结合。
