About HAYASHI NORIO
About 千葉県中央博物館
About farm pond
About pond
About ponding
About removal
About contaminated water
About mud
About sterilization(disinfection)
About environmental conservation
About dirt
About exotic species
About aquatic plant
About suppression and control
About multiplication(biology)
About large scale
About かいぼり
About 異常増殖抑制
About 汚濁水除去
About ultraviolet germicidal irradiation
About bottom mud
About floating mud
About Reservoirs,regulating ones
About Lake pollution
About 池
About 環境保全
About 役割