Environmental impacts of nitrate-accumulating sulfur oxidizing bacteria on coastal ecosystems : Population dynamics and nitrogen metabolism

本论文主要研究了近岸海域富营养化与硝酸盐积累型硫氧化细菌的关系。实地调查的空间和时间动态的NA-Escherichia种群，2。野外调查了控制该虫种群动态的环境因子。氮代谢的实验室研究，4。现场（实验室）调查的定量影响，NA-Bronze对底栖呼吸和氮循环在沉积物-水界面和5。建立了NA-Bronchial栖息的海岸海洋沉积物中底栖呼吸和氮循环的数学模型。为了研究NA-Escherichia coli种群的时空动态，建立了计算NA-Escherichia coli种群生物量和估算单根丝状体胞内NO_3浓度的方法。建立了基于克隆文库的定量PCR技术和FISH技术 关于我们 为生物量计数而私奔为了研究控制NA-BROSINE种群动态的环境因素，研制了一套原位微剖面测量系统，用于测量沉积物-水界面的微环境。为定量研究NA-NH 4+对底栖呼吸和沉积物-水界面氮循环的影响，构建了原位通量箱。利用这些方法和仪器，在东京湾的两个站进行了为期两年的季节性野外调查，每隔一个月或两个月进行一次。在NA-NH3-的氮代谢方面，<15>用NH3-N技术对在实验室条件下建立的NA-NH3-沉积物柱样进行了研究，结果表明，NA-NH3 - 80%以上被还原为NH 4+。基于NA-BEM的近岸海洋沉积物底栖呼吸和氮循环数学模型是基于两个并行计算程序（模块）：地球化学模块，以及ii.一个描述NA-酶运动的生物学模块，特别是其胞内NO_3-池。因此，通过耦合生物地球化学模块和生物模块，建立了NA-BEM模型。在生物学NA-BRA模块中，NA-BRA丝被描述为响应外部微环境的“自操作粒子”（自动机）。模型定量地表明，NA-BPO与沉积物内部氮负荷的增加和沉积物反硝化作用的减少密切相关。少

The following studies have been conducted to clarify the relationships between eutrophication in coastal marine environments and nitrate-accumulating sulfur oxidizing bacteria (NA-SOB); 1. Field investigation of spatial and temporal dynamics of NA-SOB populations, 2. Field investigation of environmental factors controlling the population dynamics of NA-SOB, 3. Laboratory investigation of nitrogen-metabolism of NA-SOB, 4. Field (laboratory) investigation of quantitative effects of NA-SOB on benthic respiration and nitrogen cycling at sediment-water interface and 5. Development of mathematical model of benthic respiration and nitrogen cycling in coastal marine sediments where NA-SOB dwells on or in. To investigate the spatial and temporal dynamics of NA-SOB populations, methods to enumerate biomass of each NA-SOB population and to estimate intracellular-NO_3- concentration in a single filament had been developed. Quantitative PCR based on clone library and FISH analysis had also been dev … More eloped for biomass enumeration. To investigate the environmental factors controlling the population dynamics of NA-SOB, an in situ micro-profiling system with micro-sensors had been developed to measure micro-environments at sediment-water interface. To investigate the quantitative effects of NA-SOB on benthic respiration and nitrogen cycling at sediment-water interface, an in situ flux chamber was constructed. With those methods and instruments, seasonal filed investigation had been performed at one or two months intervals for two years at two stations in Tokyo Bay. Regarding the nitrogen -metabolism of NA-SOB, ^<15>N technique was applied to the experimental sediment core with NA-SOB established under laboratory conditions and showed that more than 80% of the intracellular-NO_3- is reduced NH_4+. The mathematical model of benthic respiration and nitrogen cycling in coastal marine sediments with NA-SOB was based on two parallel calculation procedures (modules); i. a biogeochemical module and ii. A biological module describing the movement of NA-SOB and their intracellular pools of NO_3- in particular. Thus, the NA-SOB-model was built by coupling the biogeochemical module to the biological module. In the biological NA-SOB module a NA-SOB filament was described as a "self-operating particle" (automaton) responding to external micro-environments. It has been quantitatively shown with the model that NA-SOB is deeply concerned in the increase in the internal nitrogen loading from the sediment and in the decrease in the sediment denitrification. Less