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Location of Charlie-Gibbs Fracture Zone (CGFZ), the Hecate and Faraday seamounts and study location for the TOSCA survey (in blue box) in the North Atlantic Ocean, on the Mid-Atlantic Ridge (MAR). The boundaries of the North and South CGFZ marine protected areas (MPA) are shown in red and yellow, respectively. The North Atlantic Current (NAC) is shown in green. The Deep Western Boundary Current (DWBC)
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The Charlie-Gibbs Fracture Zone (CGFZ) is a prominent geological feature offsetting the Mid-Atlantic Ridge (MAR), consisting of two parallel fractures, creating a highly variable seafloor bathymetry. It has been defined as the most important latitudinal biodiversity transitional zone on the MAR. Despite this recognition, the faunal communities livi...
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... a considerable effect on the biological communities inhabiting this region ( Alt et al. 2019;Bell et al. 2016 Krylova 2013;Priede et al. 2013). The Charlie-Gibbs Fracture Zone (CGFZ) is an area of two parallel transform faults (the Charlie and the Gibbs) that offsets the MAR by over 340 km, making these the longest faults in the North Atlantic ( Fig. 1), and which has also been recognized as an important biogeographic boundary (Calvert and Whitmarsh 1986;Gebruk et al. 2010). Previous studies have looked at the differences in species composition and abundance on the MAR and found significant differences between the north and south of the CGFZ ( Alt et al. 2019;Bell et al. 2016;Gebruk ...
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... CGFZ is topographically unique as it includes northsouth and east-west bathymetric barriers (the fracture zone itself and the MAR axis, respectively) (Gebruk and Krylova 2013). The North Atlantic Current crosses the MAR over the CGFZ at 53°N (Fig. 1), which determines the boundary of the Sub-Polar Front at its northernmost point and creates an oceanographic boundary to the north and south due to differing water masses ( Alt et al. 2019;Priede et al. 2013;Read et al. 2010). The Subarctic Intermediate Water makes up the surface layer and is brought in by eastward flow, resulting in ...
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... water masses ( Alt et al. 2019;Priede et al. 2013;Read et al. 2010). The Subarctic Intermediate Water makes up the surface layer and is brought in by eastward flow, resulting in the freshest Labrador Sea Water occurring between 1000 and 1500m ( Schott et al. 1999;Shor et al. 1980). The deeper water mass is the Iceland-Scotland Overflow Water (Fig. 1), found below 2000m and originating from the Iceland-Scotland Ridge, in the North East Atlantic ( Racapé et al. 2019;Schott et al. 1999). The Iceland-Scotland Overflow Water is driven west through the CGFZ by the Deep Western Boundary Current ( Racapé et al. 2019;Read et al. 2010;Saunders 1994). This complex oceanography may have ...
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... Comparing the appearance, the deep sea oor area of the Azores has a similar character to the abyssal plains, ne sediment, and limited hard substrate available. However, this sampled area is in the broader region around the MAR, which is characterized by faults, fracture zones and abyssal plains covered with volcanic rocks [73]. Fracture zones show high species diversity was observed on the steep slopes and rocks [74]. ...
The depths of the North Atlantic Ocean host a species-rich fauna providing heterogeneous habitats from thermal vent fields to cold-water coral reefs. With the increasing threat of destruction of deep-sea habitats due to human impacts, such as demersal fishing and the beginning of deep-sea mining, an analysis of the diversity and distribution of species is crucial for conservation efforts. Brittle stars occur in high biomasses, contributing to the biodiversity of the seafloor. We collected specimens during several scientific expeditions to gain a more detailed insight into the brittle star diversity in the North Atlantic Ocean. The integrative approach to identify the species with DNA barcoding (mtCOI) in combination with morphological studies revealed 24 species. Most species are previously known from the North Atlantic, but sequences for 13 species are newly added to public repositories. Additionally, we successfully applied the MALDI-TOF-MS proteomic analysis for 196 specimens with known COI barcodes. This results in a congruent species delimitation demonstrating the functionality of proteomics for identification of brittle stars.
This dataset significantly expands our understanding of the taxonomic and genetic diversity and contributes to publicly available data. It emphasizes the importance of considering habitat heterogeneity for large scale patterns of biodiversity.
... Industrial activities such as drilling for fossil energy resources (Fang et al., 2018), bottom trawling (Wurz et al., 2021) or mine waste disposal (Scanes et al., 2018) are impacting sponge grounds throughout the NAO. Sponges also have been shown to be abundant in areas of potential interest for mining operations along the Mid-Atlantic Ridge (Gebruk et al., 2010;Keogh et al., 2022). The demosponge species Geodia barretti Bowerbank, 1858 is one of the dominating species in sponge grounds throughout the NAO (Klitgaard and Tendal, 2004;Cárdenas and Rapp, 2015). ...
... S EAFLOOR substrate information is critical for benthic habitat mapping and marine ecosystem management [1], [2], [3]. Since full coverage substrate maps cannot easily be created from point samples (e.g., grabs, videos) as a result of the time required for collection and their discrete spatial extent, the most common approach for producing seafloor substrate maps is to link surrogate variables as obtained from bathymetric or backscatter data to ground truth observations [1], [4]. ...
Backscatter image can be used to extract features for seafloor substrate classification. Currently, object-based method is a mainstream solution for image analysis. However, determining the optimal scale for image segment using traditional object-based method is a challenge. In this paper, we proposed an automatic method to select the optimal scale for each backscatter image pixel based on classification uncertainty. Then, the backscatter image features are extracted at the optimal scale and integrated with the bathymetric features to form the normalized multibeam echo sounder (MBES) features. Finally, a supervised classification model is established by relating the MBES features and ground truth data. Experimental results indicate the overall accuracy reaches 85.41% and the Kappa coefficient is 0.7935, which proved that the proposed method performed better than traditional methods and can be transferable to other studies.
... These maps represent habitat types, and can be used to monitor changes over time, and inform management decisions. Traditionally, benthic habitat mapping has employed multibeam echosounder data acquisition (Brown et al., 2011;Trzcinska et al., 2020) and underwater imagery collection and annotation (Keogh et al., 2022;Mohamed et al., 2022). ...
... Underwater video surveys have recently gained significant interest for benthic habitat identification and classification (Keogh et al., 2022;Mohamed et al., 2022;Ternon et al., 2022). Videos are usually recorded using high-definition (HD) cameras mounted on remotely operated vehicles (ROVs) (Robert et al., 2017;Keogh et al., 2022). ...
... Underwater video surveys have recently gained significant interest for benthic habitat identification and classification (Keogh et al., 2022;Mohamed et al., 2022;Ternon et al., 2022). Videos are usually recorded using high-definition (HD) cameras mounted on remotely operated vehicles (ROVs) (Robert et al., 2017;Keogh et al., 2022). These videos, in turn, are converted into 2D images to generate 3D point clouds using SfM photogrammetry (Casella et al., 2017;Price et al., 2021;Ventura et al., 2022). ...
Benthic habitats mapping is essential to the management and conservation of marine ecosystems. The traditional methods of mapping benthic habitats, which involve multibeam data acquisition and manually collecting and annotating imagery data, are time-consuming. However, with technological advances, using machine learning (ML) algorithms with structure-from-motion (SfM) photogrammetry has become a promising approach for mapping benthic habitats accurately and at very high resolutions. This paper explores using SfM photogrammetry and extreme gradient boosting (XGBoost) classifier for benthic habitat 3D mapping of a vertical wall at the Charlie-Gibbs Fracture Zone in the North Atlantic Ocean. The classification workflow started with extracting frames from video footage. The SfM was then applied to reconstruct the 3D point cloud of the wall. Thereafter, nine geometric features were derived from the 3D point cloud geometry. The XGBoost classifier was then used to classify the vertical wall into rock, sponges, and corals (Case 1-three classes). In addition, we separated the sponges class into three types of sponges: Demospongiae, Hexactinellida, and other Porifera (Case 2-five classes). Moreover, we compared the results from XGBoost with the widely used ML classifier, random forest (RF). For Case 2, XGBoost achieved an overall accuracy (OA) of 74.45%, while RF achieved 73.10%. The OA improved by about 10% from both classifiers when the three types of sponges were combined into one class (Case 1). Results showed that the presented 3D mapping of benthic habitat has the potential to provide more detailed and accurate information about marine ecosystems.
This chapter describes past and present publication trends in octopus research following a systematic mapping approach. Publication rates in popular research topics such as life history and ecology are decreasing, while others are increasing and taking the spotlight. Interest in behaviour has seen a considerable uptick in recent years. Also, rapid advances, emerging tools, and widespread access to DNA sequence information have stimulated an increased focus on topics relating to genomics & evolution. Research related to diversity & bBiogeo-graphy is also increasing, especially in the context of the concurrent biodiversity and climate crises. Although global change represents the least studied topic to date, interest has increased tremendously over the past 5 years, with more than double the publication rate observed for behaviour (the topic with the second largest publication rate). Our analysis also provides a geographical perspective; the food and argriculture organization region with the most octopus-related studies is the Mediterranean, followed by the Northeast and Western-Central Atlantic Ocean. Regarding species of interest, Octopus vulgaris stands out as the overwhelming front-runner Octopus Biology and Ecology. https://doi. 421 representing more than half of all records and over five times more than the second most studied species, Octopus maya. We also provide a discussion on future directions for key subjects, including behaviour and cognition, iEcology and citizen science, bio-robotics, deep-sea research, climate change, and culture and welfare, among others, with the hope of providing an agenda for future research.
