Analysis of the interactive processes of water environment between rivers and coastal regions.

为了解河流与沿岸地区水环境的相互作用过程，对东京湾及其流入河流（阿拉河）进行了长期的热结构分析，并对有明湾与筑后河之间的悬沙输移动力学进行了分析。首先，为了揭示由于城市化和气候变化的综合环境变化相关的长期河流温度变化，河流温度，城市污水温度和空气温度监测了20多年的数据进行了分析，结合东京中心地区的城市化。结果表明，城市污水温度在冬季和早春明显升高，研究区河流温度在同一季节以0.1℃/年或更高的速率同步升高。结果表明，城市热污水对土壤应力的影响较大， 关于我们 上午气温变化的直接影响比气温升高主要是由于城市化。其次，为了解紫菜养殖设施对有明湾水流系统和泥沙输移的影响，进行了紫菜养殖设施隔室水力阻力和流速分布的微尺度现场试验以及紫菜养殖设施隔室水力和悬浮颗粒物输移的宏观（湾）尺度数值模拟。现场试验结果表明，紫菜养殖网的阻力系数在0.01 ~ 0.02之间，随紫菜量的不同而变化。网和杆每隔室的紫菜养殖设施的阻力是相同的数量级的底部摩擦，但在时间变化的差异，观察在一个潮汐周期。由于紫菜网的阻力，水产养殖设施下游的表面速度降低，该设施下游端的表面边界层厚度约为1米。对有明湾头的数值模拟结果表明，紫菜养殖区的潮流和悬浮颗粒物浓度减小，而船舶航道区的潮流和悬浮颗粒物浓度则因水流阻力的相对差异而增大。少

In order to understand the interactive process of water environment between rivers and coastal regions, the long term thermal structure analysis for Tokyo bay and its inflowing river (Ara river), and transport dynamics analysis of suspended sediment between Ariake bay and Chikugo river were performed in the present study. Firstly, to reveal long-term stream temperature variation associated with composite environmental change due to urbanization and climate change, data of stream temperature, urban effluent temperature and air temperature monitored for more than two decades are analyzed in conjunction with the urbanization in the central Tokyo area. It is clarified that the temperature of urban effluents has been increasing considerably, especially in winter and early spring, and stream temperatures in the study area show a coincidental increasing trend at the rate of 0.1℃/year and more in the same seasons. It is found that the urban thermal effluent is much more influential to the stre … More am temperature changes than the direct influence of air temperature increase mainly due to urbanization. Secondly, to understand the influence of laver aquaculture facilities on the current system and sediment transport in Ariake Bay, micro-scale field experiments to measure the hydraulic resistance and velocity distribution of a compartment of an aquaculture facility and macro-(bay-) scale numerical simulations of the hydraulic and suspended particulate matter(SPM) transport were conducted. The results of the field experiment showed that the resistance coefficient of a laver aquaculture net varied from 0.01 to 0.02, depending on the quantity of laver. The resistances of the nets and poles per a compartment of laver aquaculture facility were of the same order of magnitude as the bottom friction, but differences in temporal variation were observed during a tidal cycle. The surface velocities were reduced downstream from the aquaculture facility owing to the resistance of the laver nets and the thickness of this surface boundary layer was approximately 1 m at the downstream end of the facility. The numerical simulation of the head of Ariake Bay showed that the tidal currents and SPM concentrations are reduced in the laver farming ground area, and inversely increased in the ship path regions due to the relatively differences of hydraulic resistances. Less