Salmon farming in Japan has been developing rapidly in recent years. In this paper, the backgrounds and actual situations of this industry are reported. Salmon farming had spread all over Japan as a result of the 2011 Great Earthquake. There are three types in this industry. New entering enterprises, yellowtail farmers and integrator companies in fish farming industry. In this industry, freshwater and saltwater farming are strongly combined into one integrated industry. There are some problems and difficulties in this industry. However, with huge global market it can be a successful fish farming industry even in Japan. Also, it will have positive impacts on many areas, both inland and coastal areas.
河川にダムや堰が設置されると水位の縦断的不連続が生じる.すると魚類等の河川縦断方向の移動が困難になるため,魚道の併設が必要となる.我が国の魚道の設計基準となる「魚がのぼりやすい川づくりの手引き」には幾何学形状等の推奨値が曖昧なものや記載のないものが散見される.本稿では最新の魚道研究を紹介し,遡上に適した推奨値の推定あるいは不明点の紹介を行う.また,降下に関する現状と課題も紹介する.さらに,魚道研究の方向性について言及する.
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