Studies on Mitigation of Shallow water Pollution by Organic Deposits in Semi-closed Bay

半封闭湾有机沉积物减缓浅水水体污染的研究

• 批准号: 63560230
• 负责人: KAINO Osamu
• 金额: $ 0.45万
• 依托单位: Ehime University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63560230/
• 关键词: water pollution; bottom deposits; fish culture; dissolved oxygen; organic matter; oxidation reduction potential; water quality; 底質汚染; 底質除去; 酸化還元元電位; 濁度; 現地観測値

The shallow water pollution has been caused by the transport or deposits of organic materials for breeding fish. In fact, the trend of entrophication by the bottom deposits is remarkable in semiclosed bay. The superannuation of water circumstance for fish culture has become serious recently. This field study has been examined in Kitanada semi-closed bay as following: 1. Examinations of water qualities and bottom deposits in the bay, 2. Bay topography, 3. Observation of tide and wind wave, 4. Information research for utilization of the bay, 5. Experiments on consumed oxygen by bottom deposit, 6. Analysis of bottom deposits for organic matter content, 7. Physical test of sediments and 8. Field research of benthos et al.The results of studies has been proved that: 1. Getting worse of water qualities in summer are caused by the encouraged temperature densitocline by muddiness and by fresh water, which are accelerated by an phenomenon of DO flowout on density current, an increasing of fish … More food, decrease of exchange water on effective wave, death of benthos, influence of the bay lay and crowded fish culture. 2. Moist-pellets and dry-pellets for fish have made the effective improvement of water qualities. 3. Organic matters are not related to the consumed oxygen of bottom deposit during short period. Therefore, it is necessary to examine about the condition of bottom deposit by Eh measurement. 4. Eh has been related to the consumed oxygen of short period. Both BOD and Eh are to be a characteristic about the consumed oxygen together. 5. At the incipient stage, reducing condition of bottom deposit oxidation take place fairly fast, and then the Eh indexing go up too. 6. As compared with the results 12 years ago, the organic pollution spreaded out the whole area of Kitanada semi-closed bay. 7. The wave from NW direction wind only has been influenced in the bay current effectively. 8. The decreasing effects depended on tidal forces are useful to exchange of the bay water. 9. Consequently, it is necessary that the sea water's DO have to be kept over 4 ppm after sea water exchange, and that bottom deposit's Eh have to be kept over -150 mv. Less

浅水污染是由于用于养殖鱼类的有机物质的运输或沉积造成的。事实上，在半封闭海湾，底质富营养化的趋势是显著的。近年来，我国鱼类养殖水环境老化问题日趋严重。本研究在北田半封闭海湾进行了如下研究：1。海湾水质和底质的检查，2。海湾地形，3.潮汐、风浪观测;海湾利用的信息研究，5。底存款耗氧实验;分析底质沉积物的有机质含量，7。沉积物的物理测试和8。对底栖生物等的野外调查研究结果表明：1.夏季水质变差主要是由于浑浊和淡水对温度密度梯度的促进，而异重流上的溶解氧外流现象和鱼类的增加则加速了温度密度梯度的变化 ...更多信息 食物、有效波浪交换水减少、底栖生物死亡、湾底影响和拥挤养鱼。2.鱼用颗粒饲料和干颗粒饲料有效地改善了水质。3.有机质与底存款短期耗氧量无关。因此，有必要通过Eh测量来考察底存款状况。4. Eh与短期耗氧量有关。BOD和Eh共同作为耗氧量的特征。5.在初期，底存款氧化还原条件发生较快，Eh指数也随之上升。6.与12年前相比，北田半封闭湾的有机污染已遍及整个海域。7.湾流中仅西北向风的波浪受到有效影响。8.潮汐力的衰减作用有利于湾水的交换。9.因此，海水置换后海水溶解氧应保持在4ppm以上，底泥存款的Eh应保持在-150 mV以上。少

项目成果

G.OHASHI: "Applicability of Three-Layered Flow Model to Tidal River Estuary" 6th Congress Asian and Pacific Regional Division Int.Asoc. of Hydraulic Research, PROC>. Vol.IV. 327-334 (1988)

G.OHASHI：“三层流模型对潮汐河口的应用”第六届大会亚太地区分部 Int.Asoc。

G.OHASHI: "Experimental Studies on Stratified Flow and Interfacial Wave in Tidal River Model" Proceedings of the 34st Japanese Conference on Hydraulics, 34st, p.115-120, 1990.

G.OHASHI：“潮汐河模型中分层流和界面波的实验研究”第 34 届日本水力学会议论文集，第 34 期，第 115-120 页，1990 年。

大橋行三: "感潮河川水理模型における成層流と界面波の水理特性" 土木学会水工学論文集. No.34. 115-120 (1990)

Yukizo Ohashi：“潮汐河流水力模型中分层流和界面波的水力特性”水利工程学报，日本土木工程师学会第 34 期。115-120（1990 年）。

GYOZO OHASHI: "Applicability of Three-Layered Flow Model to TidalRiver Estuary" 6th Congres Asian and Pacific Regional Division Int.Asoc.of Hydraulic Research. vol.IV. 327-334 (1988)

GYOZO OHASHI：“三层流模型对潮汐河口的适用性”第六届亚太水利研究协会亚洲及太平洋地区分会。