WEKO3
アイテム
1995年広島湾西部で発生したHeterocapsa circularisquama赤潮の発生状況と漁業被害の概要
https://fra.repo.nii.ac.jp/records/2003191
https://fra.repo.nii.ac.jp/records/200319153bcae40-753c-4397-a296-52c0559438f5
| Item type | 紀要論文 / Departmental Bulletin Paper(1) | |||||
|---|---|---|---|---|---|---|
| 公開日 | 2024-04-25 | |||||
| タイトル | ||||||
| タイトル | 1995年広島湾西部で発生したHeterocapsa circularisquama赤潮の発生状況と漁業被害の概要 | |||||
| 言語 | ja | |||||
| タイトル | ||||||
| タイトル | Occurrence of a Heterocapsa circularisquama Red Tide and Subsequent Damages to Shellfish in Western Hiroshima Bay, Seto Inland Sea, Japan in 1995 | |||||
| 言語 | en | |||||
| 言語 | ||||||
| 言語 | jpn | |||||
| キーワード | ||||||
| 言語 | en | |||||
| 主題Scheme | Other | |||||
| 主題 | Heterocapsa circularisquama; Red tide; Hiroshima Bay; Bivalve; Mortality | |||||
| 資源タイプ | ||||||
| 資源タイプ識別子 | http://purl.org/coar/resource_type/c_6501 | |||||
| 資源タイプ | departmental bulletin paper | |||||
| アクセス権 | ||||||
| アクセス権 | metadata only access | |||||
| アクセス権URI | http://purl.org/coar/access_right/c_14cb | |||||
| 著者 |
松山, 幸彦
× 松山, 幸彦× 木村, 淳× 藤井, 斉× 高山, 晴義× 内田, 卓志 |
|||||
| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | A red tide of the harmful dinoflagellate, Heterocapsa circularisquama (Peridiniales, Dinophyceae) occurred at Ohno Strait of the western part of Hiroshima Bay, Seto Inland Sea, Japan in 1995. This is the first incidence of a H. circularisquama red tide in the Seto Inland Sea. Daily surveys were carried out in the center of Ohno Strait in order to clarify the environmental conditions during the red tide and the impact of H. circularisquama on bivalves mollusks. H. circularisquama formed a red tide (> 700 cells ml-1) from 10 November to 1 December, 1995. When the cell density of H. circularisquama reached > 2,000 cells ml-1, the seawater was discolored to dark brown (coloration similar to "stained iron" or "cocoa"). Maximum cell density was 9,000 cells ml-1 at the Kuba Fishery Harbor. The occurrence of this red tide was restricted to the Ohno Strait where the water exchange rate is the lowest in Hiroshima Bay. A high cell density of this alga was observed particularly in the upper layer (0 - 2 m). Water temperature and salinity during the red tide were 14.7 - 17.8℃ and 31.7-32.2 psu, respectively. Water temperature during this red tide was 8 - 12°C lower than found for other H. circularisquama red tide in Ago Bay and Fukuoka Bay. Cell density of H. circularisquama gradually decreased when water temperatures became lower than 15°C. However, dividing cells of H. circularisquama were observed on 22 December when the water temperature was only 11.8°C. Due to the low precipitation in 1995, salinity in Hiroshima Bay during the red tide of H. circularisquama was uniformly high. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphate (DIP) during the red tide were 7.8-12.1 μ M and 0.09 - 0.14 μ M, respectively. The DIP concentration was relatively low and the DIN/DIP ratio ranged between 68 - 121. The number of diatoms was low (<200 cells ml-1) during the occurrence of H. circularisquama red tide. It is most likely that the high salinity, high DIN/DIP ratio, and low density of diatom cells enhanced the development of H. circularisquama. Populations of grazers such as tintinids and heterotrophic flagellates were low throughout the period of the H. circularisquama red tide. The red tide of H. circularisquama in Hiroshima Bay led to mass mortalities in the Pacific oyster (Crassostrea gigas), short-necked clam (Tapes philippinarum), and blue mussel (Mytilus galloprovincialis). Economic losses to cultured oyster and short-necked clam were estimated at 325 million yen. Mortality of oyster was observed at 10 - 30% in the red tide area with particularly high mortalities (50 - 90%) observed in the high cell density area (3,500 - 9,000 cells ml-1). Mortality of the blue mussel was observed at 9.5% in the area of 1,000 - 3,000 cells ml-1 and 30% in the area of 3,500 - 9,000 cells ml-1. Further, mortality of oysters was higher in the near surface layer (0 - 2 m) than the bottom layer (> 5 m), which was closely related to the vertical distribution of the H. circularisquama cells. Some biological assays on bivalves were conducted using samples of H. circularisquama from the natural red tide. Adult oysters died within 48 - 60h and showed vigorous clapping, extreme retraction of their mantle, and paralysis when exposed to a concentration of 11,200 cells ml-1 of H. circularisquama cells. These refusal behaviors were observed from a concentration of 20 - 50 cells ml-1 of H. circularisquama. Eighty five percent of juvenile mussels died within 4 days showing extreme retraction of their mantle, low production of byssus, and sustained valve closure when exposed to 10,000 cells ml-1 of natural H. circularisquama cells. The mean clearance rate of oyster and mussel decreased to 1.5% and 8.8% of normal rates, respectively when exposed to 730 cells ml-1 of natural H. circularisquama. However, reduction of the clearance rate or refusal behaviors were not observed for the filtrate (GF/F) of H. circularisquama (3,700 cells ml-1) red tide. | |||||
| 言語 | en | |||||
| 抄録 | ||||||
| 内容記述タイプ | Abstract | |||||
| 内容記述 | 1. H. circularisquama 赤潮の発生規模1995年11月から12月にかけて,広島湾でH.circularisquama の赤潮が発生した。本種の赤潮が瀬戸内海で発生したのはこれが初めてであった。この赤潮で,マガキやアサリに3億2500万円もの漁業被害が生じた。赤潮海域は大野瀬戸に限られたが,この原因はこの付近の海水交換が著しく低いためであると考えられた。また,本種遊泳細胞は主に水深0-2mの表層を中心に分布していた。2. 赤潮発生と海況の関連H. circularisquama 出現水温は 11.3-17.8℃,赤潮時の水温は14.7-17.8℃の範囲にあった。水温が15℃を下回ると細胞密度は減少した。しかし,分裂中の細胞は11.8℃においても観察された。降水量が少なかったため塩分は31.8-32.2の範囲と高めに推移していた。競合する珪藻類などの他種プランクトン,あるいは補食生物は赤潮期間中低い密度で推移した。3. H. circularisquama 発生による二枚貝斃死の実態赤潮期間中マガキで10-90%,ムラサキイガイで10-30%の斃死が観察された。漁港内など局地的に細胞密度が高かった海域を除けば,斃死率はマガキで10-30%,ムラサキイガイで約10%であった。H. circularisquama の細胞密度が高い海域や細胞の多い表層に近い所の個体ほど斃死率が高かった。また,10,000-11,200 cellsml- の H. circularisquama を用いて斃死実験を行った結果,マガキは2-3日間で,ムラサキイガイは4日間でほとんど斃死した。 | |||||
| 言語 | ja | |||||
| bibliographic_information |
ja : 南西海区水産研究所研究報告 en : Bulletin of Nansei National Fisheries Research Instituite 巻 30, p. 189-207, ページ数 19, 発行日 1998-03 |
|||||
| 出版者 | ||||||
| 出版者 | 南西海区水産研究所 | |||||
| 言語 | ja | |||||
| 出版者 | ||||||
| 出版者 | Nansei National Fisheries Research Instituite | |||||
| 言語 | en | |||||
| item_10002_source_id_9 | ||||||
| 収録物識別子タイプ | PISSN | |||||
| 収録物識別子 | 0388-841X | |||||
| item_10002_source_id_11 | ||||||
| 収録物識別子タイプ | NCID | |||||
| 収録物識別子 | AN00181988 | |||||
| 情報源 | ||||||
| 識別子タイプ | Local | |||||
| 関連識別子 | nnf_k_30_189 | |||||
| 関連サイト | ||||||
| 識別子タイプ | URI | |||||
| 関連識別子 | https://agriknowledge.affrc.go.jp/RN/2010552371 | |||||
| 言語 | ja | |||||
| 関連名称 | 日本農学文献記事索引(agriknowledge) | |||||
