Study on Self-pollution Effects and Its Countermeasure in Artificial Sea Pond

A lot of artificial coasts and the water front parks were created in Japan in order to improve the water amenity recent years. Contrary to expectation, some were polluted due to the self-pollution effects. The purpose of this study is to examine the self-pollution effects and its countermeasure to depress them in the artificial sea pond. One of them was control the inflow and the residence time of sea water in the pond. When a water level were raised more than now by 35 cm, the average maximum water temperature was provisionally calculated falls by 0.8 degrees. In addition, we could propose to change the bottom material of pond made of the concrete to the mud such as in a tidal flat where various living things lived and many materials circulated.