Cold-water coral mound development underneath an eastern boundary upwelling system - the great wall of(f) Mauritania

东部边界上升流系统下方的冷水珊瑚丘发育 - (f) 毛里塔尼亚长城

• 批准号: 274220935
• 负责人: Dr. Jürgen Titschack
• 金额: --
• 依托单位: Zentrum für Marine Umweltwissenschaften (MARUM)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2015
• 资助国家: 德国
• 起止时间: 2014-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/274220935?language=en
• 关键词: Cold; water; coral; mound; development

Cold-water corals (CWC) represent globally significant carbonate factories that can form large 3-dimensional structures along the continental margins, called CWC mounds. CWC mound formation primarily depends on (i) sustained coral growth under environmental conditions that promote the formation of coral frameworks with a high baffling capacity and (ii) sediment input that stabilises the coral framework, limits bioerosion of the coral skeletons by fast burial and favours fast CWC mound aggradation. The project will focus on CWC mounds off Mauritania, where numerous mounds occur along a spectacular 190-km-long transect (17-19° N), hence being one of the largest CWC mound provinces known so far. The Mauritanian mounds exhibit heights of up to 100 m and are organised in two slope-parallel mound chains in water depths between 360 and 550 m. The Mauritanian CWC mound province differs from all other studied mound provinces by being positioned underneath a tropical eastern boundary upwelling system and being directly influenced by a well-developed oxygen minimum zone (OMZ), which exhibits values below the preferred oxygen concentrations of the dominant framework-building coral Lophelia pertusa. Prior studies showed that even though living Lophelia-colonies occur rarely today, CWC mound formation seems to stagnate since the termination of the last glacial. The project will investigate: (i) The environmental controls of CWC mound formation off Mauritania with a special focus on the interplay of food delivery, the oxygen concentration of the surrounding bottom water mass, and the influence of variable sediment input on the CWC framework as potential key controlling factors. (ii) The oceanographic forcing of the development of two slope-parallel CWC mound chains. And (iii) the influence of potential latitudinal diachronous oceanographic changes on CWC mound formation phases along the Mauritanian continental slope. Beyond the aim to understand the long-term development of the Mauritanian CWC mound province in response to changing environmental settings, this project will contribute to our understanding of the processes controlling CWC vitality and mound formation in general. Most obvious features here will be the resilience of CWC to rather low oxygen conditions and the development of slope-parallel CWC mound chains.

冷水珊瑚（CWC）代表了全球重要的碳酸盐工厂，可以形成大型三维结构沿着大陆边缘，称为CWC土丘。化学武器公约丘的形成主要取决于（一）在促进具有高阻挡能力的珊瑚框架形成的环境条件下珊瑚的持续生长，以及（二）稳定珊瑚框架的沉积物输入，通过快速掩埋限制珊瑚骨架的生物侵蚀，并有利于化学武器公约丘的快速加积。该项目将侧重于毛里塔尼亚沿海的《化学武器公约》土丘，那里沿着有许多土丘，长达190公里（北纬17-19°），因此是迄今已知的最大的《化学武器公约》土丘省份之一。这些土丘的高度可达100米，并在水深360米至550米之间的两个斜坡平行的土墩链中组织起来。CWC土墩省不同于所有其他研究土墩省被定位在热带东部边界上升流系统的下方，并直接受到发达的氧气最小区（OMZ）的影响，其表现出的值低于占主导地位的框架建筑珊瑚Lophelia pertusa的优选氧浓度。先前的研究表明，尽管活的Lophelia殖民地今天很少出现，但CWC丘的形成似乎自末次冰期结束以来就停滞不前了。该项目将调查：（i）毛里塔尼亚近海化学武器公约丘形成的环境控制，特别侧重于作为潜在关键控制因素的食物输送、周围底层水体的氧气浓度以及可变沉积物输入对化学武器公约框架的影响的相互作用。(ii)两个斜坡平行CWC丘链发展的海洋学强迫。以及（iii）潜在的纬向穿时海洋学变化对沿着南极陆坡CWC丘形成阶段的影响。该项目的目的除了是了解喀麦隆《化学武器公约》土墩省为应对不断变化的环境而进行的长期发展之外，还将有助于我们了解控制《化学武器公约》生命力和土墩形成的一般过程。这里最明显的特征将是化学武器公约的弹性相当低的氧气条件和斜坡平行的化学武器公约丘链的发展。