報告書番号

V11025

タイトル（和文）

我が国のダム・湖沼におけるカワヒバリガイの生息の可能性

タイトル（英文）

Potential distribution of golden mussel (Limnoperuna fortunei) in major dam reservoirs and lakes in Japan

概要 （図表や脚注は「報告書全文」に掲載しております）

カワヒバリガイの生息可能環境を明らかにするとともに、我が国の湖沼の環境に対する適応可能性を推定することを目的に、既存の文献や我が国における生息地の環境を調査、整理した結果、塩分濃度、溶存カルシウム濃度、pH、溶存酸素量、水温がカワヒバリガイの生息の可否を決定する要因になることが確認された。これらの要因に関して、130地点のダム・湖沼に関して、カワヒバリガイの生息可能性について検討した結果、評価対象とした本州以南の多くのダム・貯水池にカワヒバリガイが生息可能であることが明らかになった。

概要 （英文）

The aim of this study was to forecast the possibility of expansion of golden mussel (Limnoperna fortune) in Japanese river-lake system. Potential distribution was estimated based on salinity, dissolved calcium and oxygen concentrations, pH, water temperature, and water freezing as limiting factors. Initially, upper and lower limit value of environmental factors for survival and reproduction of golden mussel were elucidated from published information mostly obtained in South America, and from our data obtained by laboratory experiments and field observations. Then, potential distribution in Japan was examined for 130 lakes from Hokkaido to Kyushu area based on the information of environmental conditions in these lakes. The salinity, dissolved calcium and oxygen, and temperature were suitable for survival of golden mussel at all of these lakes. The pH values observed at two lakes in the Tohoku district were lower than the limit value, and water freezing was the limiting factor for survival during the winter season at 30 lakes including Hokkaido. Due to greater range of suitable conditions for survival and reproduction, this species has potential to distribute in almost all dam reservoirs and natural lakes in the south of Honshu in Japan.

報告者

キーワード