Fireflies
In Japan, fireflies have been sung in songs and written in poems. It can be said that people and fireflies have lived together.
When we were very young, it was not so rare to see the lights of fireflies. But now, we can hardly catch sight of them. Why? We surveyed the ralationship between nature and fireflies and the habitation of fireflies in Nara Prefecture. From this, we examined the environment around us.
Year by year, the water pollution is getting worse and worse. The main source of water pollution is the sewage from our houses. The second is industrial waste water. Insecticides kills not only harmful insects but also fireflies. We surveyed the population density, of the factory area and of cultivated acreage. We compared it with the firefly's natural habitat.
Our finding was that fireflies could not live in the place where there are a lot of people, factories and fields. They cannot survive in polluted water. THey can live in the water which contains a lot of O2 and nourishment. THe water pollution is the biggest cause of the fact that fireflies are decreasing in number.
There is another cause. The river banks have been repaired and strengthened by concrete walls. So fireflies cannot lay eggs, or young fireflies cannot creep into the ground--which means they cannot live at all. We all want to live in pleasant surroundings and like the beautiful scene. But what is beauty? Which do you like better, the river reinforced with concrete or the earth brook where many fireflies live? This may be important alternatives.
( Authors : Sasaki ,Yoshida , Ichikawa , Tanimura , Watanabe , Terashima , Nakanishi , Morita )
