Research on flow field and rehabilitation of aquatic environment in the Ariake Sea

有明海流场与水环境修复研究

基本信息

批准号：
14205075
负责人：
KOMATSU Toshimitsu
金额：
$ 35.03万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
2002
资助国家：
日本
起止时间：
2002 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14205075/
关键词：
Ariake Sea Bottom Roughness flow structure in-situ observation numerical simulation model experiment water purification aquatic environment in coastal area 海水交換流動構造貧酸素水塊流況制御底質富栄養化赤潮流況制御技術

项目摘要

1)A large scale in-situ observation project was carried out in the overall northern part of the Ariake Sea in summer, 2003. Flow and stratification structures under a strong stratification of density due to heavy rainfalll were obtained. 2)It is confirmed from results of field observations that flow structure at the mouth of the Isahaya Bay depends on tidal condition (spring-neap variation), but strong flow along shore of the Shimabara Peninsula dose not. 3)Decreasing trend of velocity at four points in the Ariake Sea was confirmed. It is considered that the Isahaya sea-dyke affects flow structure from the inner area of the Isahaya Bay to the center area of the Ariake Sea. 4)In-situ observations of tidal current and stratification in overall area of the Isahaya Bay were carried out at neap tide in 2004. As a result temporal variation of 3-dimensional flow structure was obtained. 5)It was confirmed by multi-regression analysis that a flow field in the northern area of the Ariake Sea is … More deeply affected by a wind field. 6)Characteristics of bottom sediment distribution around river mouth of the Chikugo River and coastal area of Saga Prefecture were clarified by grain size and nutrients analysis for core samples of bottom sediment. 7)The sigma-coordinate 3-D numerical model of tidal current cooperated with tidal wetland sub-model was developed. 8)It was confirmed from results of field observations of dissolved oxygen and tidal current at the mouth of the Isahaya Bay that oxygen depression depends on inflow discharge of fresh water from rivers and the Isahaya sea-dyke. 9)The algorithm to estimate a distribution of transparency from a satellite image was developed by using the dataset of field observations. 10)Model and numerical experiments to investigate activation effect of the Bottom Roughness installed in the Ariake Sea on tidal exchange was carried out. The tidal exchange between the northern area and the southern area can be restored to the original state before constructing the Isahaya sea-dyke by this method. 11)Upwelling current by the Bottom Roughness was confirmed by a prototype experiment in the Isahaya Bay. Less

1）2003年夏季，对有明海北部整体进行了大规模现场观测，获得了强降雨造成的强密度层结下的水流和层结结构。2）证实了这一点。现场观测结果表明，谏早湾口的水流结构取决于潮汐条件（春潮变化），但岛原半岛沿岸的强水流则不然。 3)确认了有明海4处速度的下降趋势，认为谏早海堤影响着从谏早湾内部区域到有明海中心区域的水流结构。）2004年小潮时对谏早湾全区的潮流和层化进行了现场观测，得到了3维水流结构的时间变化。 5）通过多元回归分析证实，有明海北部地区的流场受风场影响较深。 6）筑后川河口周边及沿岸底部沉积物分布特征。通过底部沉积物核心样品的粒度和营养成分分析，明确了佐贺县的面积。7）建立了与潮汐湿地子模型配合的西格玛坐标3D潮流数值模型。 8）根据谏早湾口溶解氧和潮流的现场观测结果证实，氧含量降低取决于河流和谏早海堤的淡水流入量。 9）估计分布的算法。利用实地观测数据集开发了卫星图像的透明度。 10) 进行了模型和数值实验，以研究安装在有明海的底部粗糙度对潮汐交换的激活效果。通过这种方法，可以将北部地区和南部地区之间的水流恢复到修建谏早海堤之前的原始状态。 11）在谏早湾进行的原型实验证实了由底部粗糙度引起的上升流。