Hydrothermal activity and deep-ocean biology of the Mid-Cayman Rise

开曼中隆隆的热液活动和深海生物学

基本信息

批准号：
NE/F017758/1
负责人：
Bramley Murton
金额：
$ 10.66万
依托单位：
NATIONAL OCEANOGRAPHY CENTRE
依托单位国家：
英国
项目类别：
Research Grant
财政年份：
2009
资助国家：
英国
起止时间：
2009 至无数据
项目状态：
已结题

来源：
https://gtr.ukri.org/projects?ref=NE%2FF017758%2F1
关键词：
Hydrothermal activity deep ocean biology

项目摘要

We propose to investigate the world's deepest undersea volcanic ridge for the first time to obtain a vital piece in a global jigsaw puzzle of deep-sea life, advancing our understanding of patterns of biodiversity in our planet's largest ecosystem. Our proposal targets the Mid-Cayman Rise (MCR), an undersea volcanic ridge where ocean crust is being created in the Caribbean Sea. In common with all such ridges examined so far, we expect to find hydrothermal vents on the MCR: hot springs that support rich communities of deep-sea life. Investigations of hydrothermal vents over past 30 years have found hundreds of new animal species and shown that vents are more common than originally realised. Understanding how species survive in these unlikely havens has revolutionised ideas about how ecosystems can be supplied with energy and even provided clues to the origins of life. But we have yet to understand what controls the global distribution of species in these island-like extreme environments. East Pacific vents, for example, are home to metre-long tubeworms, but those animals are not known at Mid-Atlantic vents. The MCR presents a unique opportunity to determine the factors responsible for such patterns. The MCR has a deep-water connection with the Atlantic, so its vents may be inhabited by species related to those of the Mid-Atlantic Ridge. But before the Isthmus of Panama closed ~3 million years ago, there was also a deep-water connection with the eastern Pacific. The MCR may therefore harbour species related to those of the eastern Pacific, constituting a 'missing link' between the two oceans. Alternatively, the MCR may also host species unlike any found elsewhere, as a consequence of its depth and isolation from other volcanic ridges. Characterising its vent communities should therefore reveal the roles of ocean currents, geological history, depth and isolation in determining global distributions of vent species. As much of what we know about the dispersal of deep-sea species in general comes from studying these systems, this will advance understanding of patterns of deep-sea biodiversity. Because of this potential, the international Census of Marine Life has identified the MCR as a priority for investigation. From analogies with other ridges, we also expect a variety of types of hydrothermal vent on the MCR. These include high-temperature systems associated with an undersea mountain where rocks from the Earth's mantle may be pushed through the overlying crust. We also anticipate cooler alkaline vents on the ridge, created by reactions between seawater and exposed mantle rocks. And vents towards the ~6000 m maximum MCR depth are expected to have record high temperatures and unusual geochemistry, as a result of pressure-driven differences in the reactions in the crust that create them. Such vents have a high potential for new animal species and novel microbes adapted to them. We therefore propose to study the geology and hydrography of the world's deepest seafloor spreading centre, using established techniques to locate all hydrothermal vents along its ~110 km length. This will include using NERC's new Autosub 6000 autonomous underwater vehicle to pinpoint vents on the seafloor. We will then visit those vents with the UK's deep-diving robotic vehicle Isis to sample their geology, geochemistry and biology. Analysing these samples will confirm the geochemical processes driving the vents and reveal the evolutionary and genetic relationships of their inhabitants to vents elsewhere. We will also collect samples for international programmes in marine microbiology and biotechnology and share our discoveries with the wider public through an outreach programme. By using cutting-edge technology to investigate this part of our planet for the first time and answer a key question in deep-sea science, this proposal addresses NERC's goal of delivering world-class environmental research at the frontiers of knowledge.

我们建议第一次调查世界上最深的海底火山山脊，以在全球深海生活的全球拼图游戏中获得重要作品，从而促进我们对地球最大生态系统中生物多样性模式的理解。我们的提议针对中期山（MCR），这是一个海底火山脊，在加勒比海正在创建海壳。与到目前为止所检查的所有此类脊相同，我们希望在MCR上找到水热通风孔：温泉，以支持深海生活的丰富社区。过去30年来对水热通风孔的研究发现了数百种新动物物种，并表明通风孔比最初实现的更常见。了解这些物种在这些不太可能的避风港中如何生存已经彻底改变了关于如何为生态系统提供能量，甚至提供了生命起源的线索。但是，我们尚未了解是什么控制这些类似岛屿的极端环境中物种的全球分布。例如，东太平洋通风孔是米长管的所在地，但这些动物在中大西洋的通风口却不知道。 MCR提供了一个独特的机会，以确定负责此类模式的因素。 MCR与大西洋有着深水的联系，因此其通风孔可以被与中大西洋山脊相关的物种居住。但是，在巴拿马的地峡关闭300万年前之前，与东太平洋有着深厚的联系。因此，MCR可能藏有与东太平洋相关的物种，构成了两个海洋之间的“缺失联系”。另外，由于其深度和与其他火山脊隔离的结果，MCR也可以与其他地方不同。因此，表征其发泄群落应揭示洋流，地质历史，深度和隔离在确定排气物种的全球分布中的作用。我们对深海物种的分散的了解中的许多信息来自研究这些系统，这将提高人们对深海生物多样性模式的理解。由于这种潜力，国际海洋生物的人口普查已确定MCR是调查的优先事项。从与其他山脊的类比中，我们还期望MCR上有多种类型的热液通风孔。其中包括与海底山相关的高温系统，地下室的岩石可能会穿过上面的地壳。我们还期待山脊上的冷却器碱性通风孔，这是由海水和裸露地幔岩石之间的反应产生的。朝向约6000 m最大MCR深度的通风孔预计将具有创纪录的高温和异常的地球化学，这是由于压力驱动的壳构成它们的反应差异的结果。这种通风孔对新动物物种和适应它们的新型微生物具有很高的潜力。因此，我们建议使用既定的技术来研究世界上最深的海底蔓延中心的地质和水文学，以定位约110公里长的所有热液通风孔。这将包括使用NERC的新型AutoSub 6000自动驾驶水下车辆来查明海底通风口。然后，我们将访问英国深水自动车辆ISIS的通风孔，以品尝其地质，地球化学和生物学。分析这些样品将确认驱动通风孔的地球化学过程，并揭示其居民与其他地方通风口的进化和遗传关系。我们还将为海洋微生物学和生物技术方面的国际计划收集样本，并通过外展计划与更广泛的公众分享我们的发现。通过首次使用尖端技术来研究我们星球的这一部分，并回答深海科学中的关键问题，该提案解决了NERC在知识前沿提供世界一流环境研究的目标。