A study on the water purification in closed water area including bottom sludge and the revival of water environment for water student creature

研究了利用微泡技术净化天然水体包括底污泥和水生生物的水环境。主要结果如下：首先，将空气微泡和纯氧微泡供给较浅坝湖下层无氧水体，改善水质。在装置设置点周围约100 m上下流道范围内，观察到微泡扩散引起的水质变化。其次，将微泡技术应用于北海道浑卡湾扇贝养殖，缩短了养殖周期，改善了养殖工作环境，提高了扇贝的口感。明确了微泡对扇贝血流量的促进作用。第三，将微泡技术应用于Ago Bay珍珠养殖，实现了促进珍珠壳生长和防止珍珠壳死亡。在此基础上，研究了微纳气泡的物理和化学特性，并发现了提供气泡的两种薄壳的生理活性。

The water purification in natural waters including the bottom sludge and the revival of the water environment for the water student creature by using the micro-bubble technology ware investigated. The main results are as follows.First, air micro-bubbles and pure oxygen micro-bubbles were supplied to the lower layer made oxygen-less waters in the comparatively shallow dam lake, and the water quality was improved. A change in the water quality due to the diffusion of the micro-bubble was observed around the device establishment point in the range of about an up-down flow way 100 m.Second, micro-bubble technology was applied to scallop culture at Hunka Bay in Hokkaido, and shortening of the culture period, the improvement of the culture working environment and the taste were realized. And the effect on scallop blood flow promotion by the micro-bubble was made clear.Third, micro-bubble technology was applied to the pearl culture in Ago Bay, and the growth promotion of pearl shells and prevention of the death of the shells were realized.On the base of these results, the physical and chemical characteristics of micro-nano bubbles were investigated and the physiological activity of two sheet shells to provide the bubbles was found.