Environmental Impact due to the Effects of River Inflow Load in the Estuaries of Ariake Sea

(1)对有江海的全部海域以及泗川河和Midorikawa河的两个河口进行了潮流和海浪的数值分析。这些地区的速度场特征和悬浮固体浓度分布作为潮汐水平和河流流入速率的函数进行了评估。此外，还提出了分析潮滩及其沟壑形态的数值方法。(2)考虑了熊本县测量的潮滩地形长期（1924-1990）变化。此外，还测量了潮滩上的潮流和悬浮物浓度，讨论了潮滩的垂直特征。(3)通过底栖动物生态调查结果，探讨了白川河和Midorikawa河河口沉积物的污染物水平。(4)本文介绍了在有江海域（200m*200m） 30个研究样地取样的潜在反硝化和硝化速率、COD、H_2S的化学分析结果。为了调查有明海岸的水质，选取了近入海口-远入海口4个不同距离、不同深度的采样点。(5)在经筛分降解的沿海海洋沉积物填充的PVC管中研究了五彩沙蚕的体外效应。本实验的目的是确定沉积物的变质对反硝化的影响。(6)在多玛那县水田横岛填海工程中，对空气海盐的空间分布进行了实地测量。建立了考虑海盐颗粒下落速度和降雨影响下海盐浓度扩散的数值模型。研究了大气海盐在气象条件下的分布特征。此外，采用问卷调查的方法，对沿海地区居民对环境因素的认知和意识进行了调查。少

(1)Numerical analysis of tidal flows and ocean waves were performed for all of Ariake-sea and the both estuary of Sirakawa and Midorikawa rivers. Velocity field characteristics and concentration distributions of suspended solids in those areas were evaluated as a function of tidal levels and river inflow rates. Also, numerical methods for analyzing the form of tidelands and their gullies were developed.(2)Long term (1924-1990) variation of the tidal flat topography measured by Kumamoto prefecture was considered. In addition, tidal flow and concentration of suspended solids were measured over the tidal flat, which vertical characteristics were discussed.(3)The Pollutant levels of sediments in the estuaries of Shirakawa and Midorikawa rivers were discussed through the ecological survey results of benthos.(4)The current study presents the results of chemical analyzes of the potential denitrification and nitrification rates, COD,H_2S in samples collect from 30 study plots located in a grid … More (200m*200m) in Ariake-sea. Four sampling points located at different distance and Different depth, near estuary-far estuary, from Midorikawa river, were selected in order to investigation the water quality in Ariake coastal.(5)The in-vitro effect of Nereis Divesicolor has studied in PVC tubes filled with a coastal marine sediment defaunated by sieving. The aim of this experiment was to determine the effect of sediment defaunation of denitrification.(6)Field measurements of the space distribution of air-born sea-salt were carried out at the Yokosima reclamation by the drainage field in Tamana county. Numerical models that take into account fall velocities of sea-salt particles and sea-salt concentration diffusion due to rainfall effects were developed. Distribution characteristics of the air-born sea-salt as effected by meteorological conditions were also investigated. Furthermore, the investigation of the perceptions and awareness about environmental factors to inhabitants living in coastal area were performed by using a questionnaire survey. Less