海下水蝕洞
海下水蝕洞(英語:Anchialine pool,/ˈæŋkiəlaɪn/或/ˈæŋ.kiə.lin/),又稱海水湖(英語:Marine lake),是地底與海洋相連的內陸水體,由於受到雨水、地下水及潮汐影響,內部存在淡水、半鹹水及鹹水並依照密度垂直分層,主要分布於熱帶或亞熱帶地區的喀斯特及火山地形。因為其環境的特殊性,其內部有有別於海洋或湖泊的生態系,並且擁有一些甲殼類的特有種生物,例如夏威夷紅蝦。[1]
語源
[编辑]英語「anchialine」一詞由荷蘭動物學家利克·霍采斯於1973年首度提出,該詞由希臘文「ankhialos」衍生而來,意為「濱海的」,最初用來描述隨著潮汐起落的陸上鹹水池,[註 1][2]1997年Brock, Richard E.和Kam, Alan K.H.再添加「滿潮時與其他水體分離」的原則。[註 2][3]此外,海水湖則是對湖面較大、且退潮時底部不乾涸的海下水蝕洞的通俗稱呼。[4]
形成及分布
[编辑]海下水蝕洞主要分為兩類:石灰岩質及火成岩質。前者為喀斯特地形因沉水作用形成(同時為石灰阱),又因熱、亞熱帶地區石灰岩地形較發達,故此類海下水蝕洞分布多位於熱帶及亞熱帶,例如猶加敦半島、加勒比群島、地中海石灰岩地區、帛琉群島和印尼群島等;後者為熔岩管被海水侵入,多分布於火山帶,例如夏威夷群島、加拉巴哥群島、加納利群島和薩摩亞群島等。[4]
環境及生態
[编辑]濱海地區的地下水層與海水並不會在海岸線交會,而是形成一個類似透鏡的構造(淡水透鏡體),來自陸地的淡水會覆蓋來自海洋的鹹水,並在其交界處產生鹽躍層,厚度幾公分至幾公尺不等。[5]在鹽躍層中鹽度變化劇烈,大多由半鹹水和淡水組成,且因密度的變化使得底部的鹹水常年處於低氧環境中,即使在溫帶的冬季,淡水的密度仍較海水小。此外,由於底部的缺氧環境,行光合作用以進行初級生產的生物較少,取而代之的是硫還原菌透過將水中豐富的硫化氫轉換為硫獲取有機物,底部的水質會較頂部混濁。[6]
海下水蝕洞的生物組成與海洋類似,其中甲殼類的生物較為豐富,除了槳足綱的生物外(在1979年前被認為已滅絕,現存28種,活化石之一),亦有混足目[7]、平腳目[8][9]的特有種存在;然而部分種類的生物在地理分布上呈現隔離分布,例如槳足綱分布在加勒比海、加那利群島及澳洲西海岸;原蝦科分布在夏威夷、阿森松島和百慕達群島等地。這樣的分布情形被認為可能與特提斯洋的存在相關,[10]但目前沒有足夠的遺傳學證據證明這個猜想。[11]此外,夏威夷紅蝦(Halocaridina rubra)也是原生在海下水蝕洞中的生物,近年來人工養殖的數量有所成長。[12]海下水蝕洞中的魚類包括來自胎鼬䲁科、塘鱧科、鰕虎科和合鰓魚科,分布在加拉巴哥群島、加勒比群島、猶加敦半島、菲律賓、日本和澳洲等地。[13]
參考資料
[编辑]註解
[编辑]- ^ 原文:…At several occasions red coloured caridean shrimps have been reported from tropical land-locked saltwater pools. These pools are situated at some distance from the sea, but, because the level of the water rises and falls with the tides, must have subterranean connections with the sea.…It is suggested now to use the term "anchialine" (from the Greek anchialos, near the sea) to indicate this type of habitat, rather than to have to define it each time as "pools with no surface connection with the sea, containing salt or brackish water, which fluctuates with the tides".…
- ^ 原文:…Besides the classical definition of an anchialine pool (i.e., a body of water having a measurable salinity and showing tidal fluctuations but no surface connections to the sea), the working definition of an anchialine pool used here is that it is isolated from other adjacent bodies of water at the highest tides. If adjacent pools show surface connections on high tides, they are considered to be part of a poll complex. A complex may have a number of depressions or basins, which through lower tides may appear as individual pools but coalesce, at higher tides.…
參考資料
[编辑]- ^ Scott R. Santos. Patterns of genetic connectivity among anchialine habitats: a case study of the endemic Hawaiian shrimp Halocaridina rubra on the island of Hawaii (PDF). 分子生態學. 2006, 15 (10): 2699–2718. PMID 16911195. doi:10.1111/j.1365-294X.2006.02965.x. (原始内容存档 (PDF)于2020-07-16).
- ^ Holthuis, L.B. Caridean Shrimps found in Land-Locked Saltwater Pools at four Indo-West Pacific Localities (Sinai Peninsula, Funafuti Atoll, Maui and Hawaii Islands), with the description of one new genus and four new species. Zoologische Verhandelingen. 1978, 128 (1): 1–48 [2020-07-14]. ISSN 0024-1652. (原始内容存档于2020-07-14) (英语).
- ^ Brock, Richard E.; Kam, Alan H. Biological and water quality characteristics of anchialine resources in Kaloko-Honokohau National Historical Park (PDF). PCSU Technical Report. 1997, 112: 19 [2020-07-14]. (原始内容存档 (PDF)于2020-07-14) (英语).
- ^ 4.0 4.1 Becking, L.E.; Renema, W.; Santodomingo, N.K. Recently discovered landlocked basins in Indonesia reveal high habitat diversity in anchialine systems. 水生科學. 2017, 677: 89–105 [2020-07-14]. doi:10.1007/s10750-011-0742-0. (原始内容存档于2020-07-14) (英语).
- ^ S. Moore, Willard. The subterranean estuary: a reaction zone of ground water and sea water. 海洋化學. 1999, 65 (1-2): 111–125 [2020-07-15]. doi:10.1016/S0304-4203(99)00014-6. (原始内容存档于2020-07-15) (英语).
- ^ Culver, David C.; White, William B. Anchialine Caves. Encyclopedia of Caves. 阿姆斯特丹: 愛思唯爾. 2005. ISBN 978-0-12-198651-3.
- ^ J. K. Lowry & M. Yerman. Mictacea. crustacea.net. 澳洲博物館. [September 3, 2007]. (原始内容存档于2012-05-14).
- ^ T. M. Iliffe. Antrisocopia prehensilis. The IUCN Red List of Threatened Species. 1996, 1996: e.T1784A7539000. doi:10.2305/IUCN.UK.1996.RLTS.T1784A7539000.en .
- ^ T. M. Iliffe. Nanocopia minuta. The IUCN Red List of Threatened Species. 1996, 1996: e.T14331A4433047. doi:10.2305/IUCN.UK.1996.RLTS.T14331A4433047.en .
- ^ Culver, David C.; White, William B. Biodiversity in Anchialine Caves. Encyclopedia of Caves. 阿姆斯特丹: 愛思唯爾. 2005. ISBN 978-0-12-198651-3.
- ^ Jaume, D.; Boxshall, G.A. Life in extreme ocean environments: anchialine caves. Marine Ecology. EOLSS. 2009. ISBN 978-1-84826-014-6.
- ^ Krause, Inken. Zwerggarnelen im Meerwasseraquarium. 德國明斯特: Natur und Tier Verlag. 2016. ISBN 978-3-86659-364-0.
- ^ Iliffe, Thomas M.; Kornicker, Louis S. Worldwide Diving Discoveries of Living Fossil Animals from the Depths of Anchialine and Marine Caves. Proceedings of the Smithsonian Marine Science Symposium. 華盛頓特區: 史密森尼學術媒體. : 269–280. doi:10.5479/si.01960768.38.1. (原始内容存档于2020-07-16).