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This topic presents the effect of water temperature on benthic invertebrate growth and assemblages at downstream site of the Dam in winter, in Japan. The surface layer water of dam was released, and the temperature was always 3-5 degrees higher than the upstream. This was because of tentative manipulation of dam. Life cycles of dominated species were faster and their body size were all larger in the downstream than the upstream. Kamimuria tibialis (Perlidae) as a predator grew faster. Also, its body weight was much heavier than in the upstream, even its body length is the same in the upstream. Periphyton biomass was also much higher, especially, filamentous species were dominated at slow current site in the downstream. Regardless of abundance of periphyton, Heptageniidae as a grazer were not increased compared with the upstream. Besides discharge control, water temperature changes invertebrate assemblages quickly. This result implies that restrict of the movement of species is need to consideration.

The growing problem of hydrogen sulfide resulting from the disposal of waste gypsum boards has yet to find an effective solution. Recent years have brought urgent calls for a means of recycling waste gypsum boards. This study focused on applications in floors, which among major structural parts are subject to particularly severe conditions. The author examined the form of gypsum after pouring, as well as the formwork and pouring methods, employing the properties of gypsum hemihydrate recycled from waste gypsum boards. The study has established specifications that overcome the problem of afterflame following a fire involving wooden fireproof construction.