著者

片野 修 細谷 和海 井口 恵一朗 青沼 佳方

出版者

日本魚類学会

雑誌

魚類学雑誌 (ISSN:00215090)

巻号頁・発行日

vol.48, no.1, pp.19-25, 2001-05-25 (Released:2010-06-28)

参考文献数

31

被引用文献数

12

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Freshwater fish in rice fields near the Chikuma River, Nagano Prefecture, were investigated by visual census and net sampling. The rice fields were classified into three types. Type 1-terraced and supplied with water from an upper pond; type 2-supplied with water from drainage ditches; and type 3-supplied and drained by separate irrigation ditches. Rhinogobius sp.OR (sensu Kawanabe and Mizuno, 1989), Misgurnus anguillicaudatus and Pseudorasbora parva were abundant in type 1 fields, whereas Tribolodon hakonensis, Carassius spp., M. anguillicaudatus and Gnathopogon elongatus elongatus were recorded in type 2 fields. Only M. anguillicaudatus was found in type 3 fields. The fish abundance and diversity did not differ significantly between type 1 and 2, but was extremely poor in type 3. The recent rearrangement of rice fields from types 1 and 2 to type 3 evidently reduced fish abundance and diversity.