Cold-water coral habitats in submarine canyons

海底峡谷是连接陆架和深海的主要运输通道。它们经常形成生物多样性热点，因为它们陡峭的地形、独特的海洋学和沉积物动力学制度创造了各种生态位，吸引了广泛的动物。最具标志性的物种群之一是冷水珊瑚，这种珊瑚可以在没有共生藻类的情况下生存。它们是深海中重要的栖息地形成生物，可作为商业鱼类的育苗场(Roberts等人，2009年)。然而，由于底拖网捕捞的影响，它们属于联合国列出的脆弱海洋生态系统(Puig等人，2014年)。除了在大陆边缘发现更知名的冷水珊瑚礁外，在海底峡谷中发现的冷水珊瑚也越来越多，海底峡谷集中了携带对珊瑚生存至关重要的有机物浓度增加的洋流。由于无法进入这种复杂的环境，人们对海底峡谷中冷水珊瑚栖息地的形成过程知之甚少。为什么某些地方被小块地殖民，而在其他地方可以找到大片珊瑚礁或空中花园(Huvenne等人，2011年)？为什么某些物种统治着峡谷的特定部分？沉积物运移、地貌学和海洋学之间的相互作用如何支配它们的发生？利用一套能够在极端峡谷环境下工作的尖端深海机器人潜水器收集的独特数据集(来自NOC的Autosub6000自主水下航行器(AUV)和ISIS远程操作潜航器(ROV)，以及来自UEA的浮力驱动海洋滑翔机)，该博士将深入了解海底峡谷冷水珊瑚栖息地的性质、形态、分布和动态，最终目的是支持保护措施。

Submarine canyons are the main transport pathways between the shelf and deep ocean. They often form biodiversity hotspots, as their steep terrain, unique oceanography and sediment dynamic regimes create a variety of niches that attract a wide range of fauna. One of the most iconic species groups are cold-water corals, types of coral that can live without symbiotic algae. They are important habitat-forming organisms in the deep sea, and may act as nursery grounds for commercial fish species (Roberts et al., 2009). However, they are among the Vulnerable Marine Ecosystems listed by the UN, due to impacts of bottom trawling (Puig et al., 2014).In addition to the better known cold-water coral reefs found along continental margins, cold-water corals are increasingly discovered in submarine canyons, which focus currents carrying increased organic matter concentrations crucial for the corals' subsistence. As a result of the inaccessibility of this complex environment, the processes of cold-water coral habitat formation in submarine canyons are poorly understood. Why are certain locations colonised by small patches, while in other locations large reefs or hanging gardens can be found (Huvenne et al., 2011)? Why are certain species dominating specific parts of a canyon? How does the interplay between sediment transport, geomorphology and oceanography govern their occurrence? Using a unique dataset gathered by a suite of cutting-edge deep-sea robotic vehicles that can work in the extreme canyon environment (the Autosub6000 Autonomous Underwater Vehicle (AUV) and ISIS Remotely Operated Vehicle (ROV) from NOC and a bouyancy-driven ocean glider from UEA), this PhD will bring insight in the nature, morphology, distribution and dynamics of cold-water coral habitats in submarine canyons, with the ultimate aim to support conservation measures.