多毛類の多様性と干潟環境 : カワゴカイ同胞種群の研究(<特集>干潟の自然,その過去と現在)

スポンサーリンク

概要

• 論文の詳細を見る

• Nereidid polychaetes often dominate in benthic communities in estuarine tidal flats. For typical example, Hediste worms, in which five morphologically similar species are known in the North Temperate Zone, often attain high density and biomass. Asian Hediste worms were previously regarded as belonging to a single species. However, recent studies could distinguish three distinct species in them, i.e., H. japonica (Izuka, 1908), H. diadroma Sato and Nakashima, 2003, and H. atoka Sato and Nakashima, 2003. It seems to be ecologically significant that three Hediste species with different life histories inhabit the same or neighboring estuaries in eastern Asia. Spawning, fertilization and early development in H. japonica and H. diadroma occur in water column after reproductive swarming of mature adults. The distribution of H. japonica is restricted to muddy tidal flats in the inner part of Ariake Sea in Japan and Korean western coasts (Yellow Sea), where tidal ranges are the greatest in Asia (mean tidal range of around 3 m or more in the spring tides). In these tidal flats, the sediment surface is severely disturbed by water movement produced by the strong tidal current. Here, H. atoka has never been found, while H. diadroma coexists with H. japonica in some areas. In H. atoka, spawning, fertilization and early development occur within (or around) a burrow without reproductive swarming, and may be unsuccessful in the unstable muddy sediments because of the difficulty of maintaining an intact burrow during this process. Local tidal amplitudes are geographically and geo-historically different, mainly affected by co-oscillating effects in relation to the coastal topography (e.g., the size of a bay) and by a long-term change of the distance between the earth and the moon. The different tidal amplitudes may be one of major environmental factors affecting evolution for the closely related burrowing species. The recent rapid depletion of Asian tidal flats due to human impact (especially those located in semi-enclosed bays) is a serious problem resulting in extreme reduction in the distributional range of unique muddy shallow-water fauna.

• 日本古生物学会の論文
• 2004-09-22

著者

• 佐藤 正典

  鹿児島大学理学部地球環境科学科

• 佐藤 正典

  鹿児島大

• 佐藤 正典

  鹿児島大学

関連論文

• 諫早湾・有明海で何がおこっているのか? (特集 有明海と長良川で何がおこっているのか?)
• 潮止め後2年半の諫早湾 : このままでいいのか?
• 大分県宇佐市寄藻川に生息するアリアケガニ個体群の発見
• 「九州の干潟を中心とした浅海域開発と環境アセスメントの問題点」1997年秋季大会シンポジウム報告
• 多毛類の多様性と干潟環境 : カワゴカイ同胞種群の研究(干潟の自然,その過去と現在)
• 有明海の重要性 : 危機に瀕した干潟生物の最後の砦[要旨]
• 鹿児島湾の重富干潟における底生動物相の変化 : 1994年と2005年の比較
• 6. Hediste属(環形動物門多毛綱ゴカイ科)における生殖・発生形質の分化(日本動物分類学会第37会大会講演抄録)
• 諫早湾潮止め後10年間の有明海における主な底生動物相の変化
• 「有明海の生物多様性保全のための四学会合同シンポジウム : 有明海の特異な生物相-諌早湾の環境復元の意義-」の報告
• はじめに
• タイトル無し

もっと見る 閉じる

スポンサーリンク