Abstract
We have investigated the effect of a commercial solution containing various kinds of microbes (commercial microbe solution), which is used in school activities for environmental purification, by using a river model equipped with gravels of river bed on a plastic tray. The activity of self-purification (decomposition of sodium dodecylsulfate, NaDS) by microbes on the surface of gravels is accelerated from the third day to the fifth day by the addition of commercial microbe solution. However, the decomposition rate of NaDS by only commercial microbe solution in the river model is lower than that of only microbes on the surface of gravels. These findings suggest that the use of the river model and commercial microbe solution is effective for science class lessons at junior high school for understanding the relationship between the self-purfication of a river and the action of microbes on the surface of gravels on river bed.
