用排兼用型水路と接続する未整備水田の構造と水管理が魚類の生息に与える影響について [in Japanese] Water Management in Unimproved Paddy Fields Connected with Dual-purpose-channel and Those State of Use by Fishes [in Japanese]
Access this Article
Search this Article
本研究は, 未整備水田を対象に水管理との関わりの中で魚類がどのように水田を利用しているか明らかにすることを目的とした.調査の結果, 次のことが明らかとなった.1) ドジョウ, タモロコ, フナ属に加え, シマドジョウも水田で繁殖していると考えられた.2) ドジョウとタモロコでは水田の利用期間が異なった.3) 魚類の繁殖期に当たる灌漑初期の水田排水の流速が魚類の溯上を促す流速帯となつていた.4) 用排兼用型水路と双方向移動可能な水口・水尻の構造は, 水田において魚類が繁殖・成育できる可能性を高め, 水田水域の個体群の維持に寄与すると考えられた.
Paddy fields having good connection with dual-purpose-channel have been disappearing by land consolidation projects and urbanization. This study clarified how fish use such paddy fields in relation with rice farming to examine a future expected model of the area. As a result of investigation, the following became clear. 1) Paddy fields functioned as reproduction field for <I>Misgurnus anguillicaudatus, Gnathopogon elongatus elongatus, Carassius</I> spp., <I>Cobitis biwae</I>, and as growth field for fries which were born in other water area. 2) <I>M anguillicaudatus</I> used paddy fields as habitat through irrigation term, but G elongatus elongatus didn't use paddy fields after midsummer drainage. 3) The velocity of drainage water was almost the same velocity as that adult fishes were promoted to carry out ascending migration at water outlet. 4) It was suggested that increase of fish biomass in a paddy field is influenced by the structure of water inlet and outlet from which fish can escape easily.
- Transactions of The Japanese Society of Irrigation, Drainage and Rural Engineering
Transactions of The Japanese Society of Irrigation, Drainage and Rural Engineering 74(4), 467-474, 2006-08-25
The Japanese Society of Irrigation, Drainage and Rural Engineering