Hydrothermalism and Deep-Water Ecosystems in the Atlantic Ocean (MSM 6 - Koordinatorantrag)

玛丽亚·S·梅里安邮轮MSM 06号由三条航段组成，覆盖了大西洋的大片海域(图1)。第一部分从法罗尔群岛开始，重点研究加的斯湾的冷水珊瑚生态系统，那里的生态系统似乎与泥火山有关。这一分支的主要目的是发现驱动珊瑚分布的主要驱动因素，并调查这些生态系统是如何在过去不断变化的环境条件下发展的。第二段和第三段都将集中进行热液系统的调查。第二段将把玛丽亚·S·梅里安号房车带到北大西洋西部中大西洋海脊的洛加切夫热液气田，计划在那里进行一项局部重点研究，以探索热液流体时空成分差异的原因及其对该喷口气田喷口群落的影响。第三段将集中在大西洋中部海脊的另一段，进一步向东，就在赤道以南。在那里，将在四个不同的喷口领域研究与大规模岩浆和构造作用对热液系统的影响有关的几个主题。为了实现模糊的设定目标，特别是对实现这些目标不可避免的海底环境进行非常详细的调查，所有三个分支都将使用遥控运载器(ROV)作为主要科学仪器，强调新技术如何使科学工作达到迄今不可能达到的水平。MSM 06/1：第一个分支的重点是对加迪斯湾冷水珊瑚生态系统的调查。在泥火山上随机发现的冷水珊瑚表明，加迪斯湾的这些地形结构可以作为冷水珊瑚的栖息地。根据这些发现，它们的区域分布似乎限于600至1350米的深度间隔。通过使用不来梅ROV Cherokee、相机雪橇OFOS(洋底观测系统)和视频引导的抓取采样器，这一分支的主要目的是确定和评估控制该区域冷水珊瑚分布的那些因素。对个别结构的详细录像观察将提供关于珊瑚与地形和海洋环境以及与珊瑚有关的动物群的小规模分布(以及大尺度分布的总和)的线索。视频观测和相关的水深和海洋调查将由水下机器人进行有针对性的动物和沉积物采样、视频定向抓取采样以及标准采样方法来补充。此外，还将提取沉积物岩芯，以研究这些冷水珊瑚生态系统在不断变化的环境条件下的发展情况，例如冰期/间冰期的变化。这次考察为Hermes项目做出了贡献，这是在欧洲联盟第六次FRP范围内资助的一个综合项目。MSM 06/2：在DFG SPP 1144的主持下进行的第二个分支的总体目标是调查热液流体的时空组成差异的原因及其对洛加切夫喷口群落的影响

RV MARIA S. MERIAN cruise MSM 06 comprises three legs that cover a large part of the Atlantic Ocean (Fig. 1). Starting at the Faroer Islands the first leg concentrates on cold-water coral ecosystems in the Gulf of Cadiz where these ecosystems seem to be related to mud volcanoes. The major aim of this leg is to detect the main forcing factors driving the distribution of the corals and to investigate how these ecosystems developed under changing environmental conditions in the past. The second and the third leg both will concentrate on the investigation of hydrothermal systems. Leg 2 will bring the RV MARIA S. MERIAN to the Logatchev hydrothermal field at the Mid-Atlantic Ridge in the western North Atlantic, where a locally focused study is planned to explore the causes for temporal and spatial compositional differences of hydrothermal fluids and their effect on the vent communities in this vent field. Leg 3 will focus on another section of the Mid-Atlantic Ridge further to the east and just south of the equator. There several topics related to the influences of large-scale magmatic and tectonic processes on hydrothermal systems will be investigated in four distinct vent fields. To achieve the ambiguous set-out goals, especially the very detailed investigation of sea floor settings inevitable to reach these goals, all three legs will employ a remotely operated vehicle (ROV) as the main scientific instrument underlining how new technologies enable scientific work on a hitherto impossible level of detail.MSM 06/1: The focus of the first leg is on the investigation of cold-water coral ecosystems in the Gulf of Cadiz. Random findings of cold-water corals on mud volcanoes have shown that these topographic structures in the Gulf of Cadiz can serve as habitats for cold-water corals. From these findings it seems that their regional distribution is limited to a depth interval of 600 to 1350 m. By employing the Bremen ROV CHEROKEE, the camera sledge OFOS (Ocean Floor Observation System) and a video-guided grab sampler, the main aim of this leg is to identify and to evaluate those factors that control the distribution of cold-water corals in this region. Detailed video observations on individual structures will provide clues about the small scale distribution (and in their sum on the large scale distribution) of the corals in relation to the topographic and oceanographic settings and on the faunal communities the corals are associated with. The video observations and related bathymetric and oceanographic investigations will be complemented by targeted fauna and sediment sampling by the ROV, video-directed grab sampling as well as by standard sampling methods. In addition, sediment cores will be retrieved to study the development of these cold-water coral ecosystems under changing environmental conditions, e.g. over glacial/interglacial changes. This expedition contributes to the HERMES project, an integrated project funded within the 6th FRP of the European Union.MSM 06/2: The overall goal of the second leg - to be conducted under the auspices of the DFG SPP 1144 - is the investigation of causes for temporal and spatial compositional differences of hydrothermal fluids and their effect on the vent communities in the Logatchev