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Locations of megafaunal surveys during ABYSSLINE cruise 01 (AB01) in the eastern Clarion-Clipperton Zone.: (a) The location of the UK-1 exploration contract area in the Pacific Ocean. (b) The location of UK-1 Stratum A in relation to the UK-1 contract area and the AB01 ROV dive site, EPIRB, which was approximately 250 km east of the UK-1 contract area. (c) A bathymetric map of UK-1 Stratum A with the locations of ROV dives indicated by circles with the dive number. All maps were created by Seafloor Investigations Ltd. for the ABYSSLINE Project using ArcGIS software (https://www.arcgis.com/features/). (c) was created using unpublished ship-based bathymetry collected during AB01.
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There is growing interest in mining polymetallic nodules in the abyssal Clarion-Clipperton Zone (CCZ) in the Pacific. Nonetheless, benthic communities in this region remain poorly known. The ABYSSLINE Project is conducting benthic biological baseline surveys for the UK Seabed Resources Ltd. exploration contract area (UK-1) in the CCZ. Using a Remot...
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... five most abundant morphotypes observed during AB01 dominated the megafaunal community, comprising nearly half (45%) of all individuals. The remaining morphotypes were generally rare, as indicated by the rank order abundance curve (see Supplementary Figure S1), with 62% of the morphotypes (84 of 136) observed fewer than ten times, and 24% (33 morphotypes) seen only once in quantitative transects. There was greater com- munity similarity at the transect level within sites (> 80% similarity) than between sites (< 68% similarity) (see Supplementary Figure S2). ...
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... UK-1 exploration contract area is located in the eastern CCZ ( Fig. 1) and has an annual POC flux to the abyssal seafloor of roughly 1 gCm −2 y −1 , i.e., ~two-fold higher than in the western CCZ 50 . During the first cruise (ABYSSLINE Project cruise AB01, RV Melville cruise MV1313, 3-27 October, 2013), we focused on a 30 × 30 km stratum (UK-1 Stratum A) centered at 13°49′ N, 116°36′ W (Fig. 1). Multibeam ...
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... in the eastern CCZ ( Fig. 1) and has an annual POC flux to the abyssal seafloor of roughly 1 gCm −2 y −1 , i.e., ~two-fold higher than in the western CCZ 50 . During the first cruise (ABYSSLINE Project cruise AB01, RV Melville cruise MV1313, 3-27 October, 2013), we focused on a 30 × 30 km stratum (UK-1 Stratum A) centered at 13°49′ N, 116°36′ W (Fig. 1). Multibeam bathymetric surveys during the cruise indicated an abyssal seafloor characterized by ridges and valleys running from NNW to SSE at 3900-4400 m depth (Fig. 1). Bottom-water temperatures were ~2 °C, bottom-water oxygen concentrations were ~3.2 ml L −1 , and our observations revealed abyssal current velocities below sediment ...
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... first cruise (ABYSSLINE Project cruise AB01, RV Melville cruise MV1313, 3-27 October, 2013), we focused on a 30 × 30 km stratum (UK-1 Stratum A) centered at 13°49′ N, 116°36′ W (Fig. 1). Multibeam bathymetric surveys during the cruise indicated an abyssal seafloor characterized by ridges and valleys running from NNW to SSE at 3900-4400 m depth (Fig. 1). Bottom-water temperatures were ~2 °C, bottom-water oxygen concentrations were ~3.2 ml L −1 , and our observations revealed abyssal current velocities below sediment erosion thresholds throughout our 16 days on station (unpublished data, ABYSSLINE ...
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... commercial Remotely Operated Vehicle (ROV) Remora III, operated by Phoenix International Holdings, Inc., performed video surveys and sample collections at five randomly-located sites: four within UK-1 Stratum A, and one ~250 km to the east of the UK-1 contract area at a site here called 'EPIRB' centered at 13°40′ N, 114°24′ W (Fig. 1). Our original study design involved surveys at random sites within Stratum A, but ROV failures limited us to four sites. Work at the EPIRB site was dictated by an emergency response to an EPIRB distress signal and, although unplanned, provided a useful broader context for our study. The ROV was equipped with two manipula- tors, four ...
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... and all metazoan specimens sequenced for a range of DNA markers at the Natural History Museum, London, with tissue samples subsequently archived and made openly-available for future taxonomic work 37,38,62 . ROV megafaunal video surveys. ROV still images and video were collected at all five sites for the "qual- itative" analysis of megafauna (Fig. 1). This analysis utilized all video from both "pilot" and "science" cameras (covering roughly 8000 m 2 ) whereas the quantitative analysis only used the high-definition imagery from the Scientific RepoRts | 6:30492 | DOI: 10.1038/srep30492 "science" camera. Due to ROV failures and altitude instability during surveys, we were able to ...
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... only used the high-definition imagery from the Scientific RepoRts | 6:30492 | DOI: 10.1038/srep30492 "science" camera. Due to ROV failures and altitude instability during surveys, we were able to obtain only four 1-km surveys, two at each of two sites (Sites 6 and EPIRB), of sufficient quality to be utilized in the quantitative assessment ( Fig. 1 and see Supplementary Table S4). At each site, both transects were conducted along random headings, with the second transect beginning within 100 m of the end of the ...
Similar publications
Analysis of the seabed composition over a large spatial scale is an interesting yet very challenging task. Apart from the field work involved, hours of video footage captured by cameras mounted on Remote Operated Vehicles (ROVs) have to be reviewed by an expert in order to classify the seabed topology and to identify potential anthropogenic impacts...
Citations
... Commonly employed sampling methods associated with exploration activities, such as core collection (box cores, multiple or piston samplers) and EBS, could deepen the SML, with some flocculent surficial sediment being completely removed and/or laterally transported and redeposited nearby (Amon et al., 2016;Jung et al., 1998). ...
The sediment mixed layer (SML) in the deep ocean is an important interface with a rich diversity of benthic organisms. With increasing ocean mineral exploration, and eventual mining, the effect of sediment mixing on deep ocean ecosystems has raised considerable concern. We evaluate the distribution patterns and driving factors of SML depth in deep ocean nodule fields using naturally occurring ²¹⁰Pb–²²⁶Ra isotopes. Results show that average SML depth has increased in Mn‐nodule fields since the end of the last century. SML processes are associated with significant desorption of ²²⁶Ra from sediments, resulting in a departure from radioactive equilibrium. By estimating possible driving factors, we conclude that anthropogenic exploration activities, rather than natural physical and/or biological drivers, are the most likely mechanism for intensified sediment mixing. ²¹⁰Pb–²²⁶Ra disequilibria may be a potential tracer for quantifying the impact of human exploration on deep‐ocean sediment mixing and associated biological and geochemical effects.
... microbes, foraminifera, invertebrate metazoans (e.g., nematodes, polychaetes, copepods, sponges, and echinoderms), fish, and, to a lesser extent, mammals (Amon et al., 2016;Pape et al., 2013;Rabone et al., 2023). Importantly, species diversity remains poorly described for both terrestrial and oceanic ecosystems, with an estimated 91% and 86% of eukaryotic species expected yet to be discovered in the ocean and on land, respectively (Mora et al., 2011). ...
The crises of climate change and biodiversity loss are interlinked and must be addressed jointly. A proposed solution for reducing reliance on fossil fuels, and thus mitigating climate change, is the transition from conventional combustion‐engine to electric vehicles. This transition currently requires additional mineral resources, such as nickel and cobalt used in car batteries, presently obtained from land‐based mines. Most options to meet this demand are associated with some biodiversity loss. One proposal is to mine the deep seabed, a vast, relatively pristine and mostly unexplored region of our planet. Few comparisons of environmental impacts of solely expanding land‐based mining versus extending mining to the deep seabed for the additional resources exist and for biodiversity only qualitative. Here, we present a framework that facilitates a holistic comparison of relative ecosystem impacts by mining, using empirical data from relevant environmental metrics. This framework (Environmental Impact Wheel) includes a suite of physicochemical and biological components, rather than a few selected metrics, surrogates, or proxies. It is modified from the “recovery wheel” presented in the International Standards for the Practice of Ecological Restoration to address impacts rather than recovery. The wheel includes six attributes (physical condition, community composition, structural diversity, ecosystem function, external exchanges and absence of threats). Each has 3–5 sub attributes, in turn measured with several indicators. The framework includes five steps: (1) identifying geographic scope; (2) identifying relevant spatiotemporal scales; (3) selecting relevant indicators for each sub‐attribute; (4) aggregating changes in indicators to scores; and (5) generating Environmental Impact Wheels for targeted comparisons. To move forward comparisons of land‐based with deep seabed mining, thresholds of the indicators that reflect the range in severity of environmental impacts are needed. Indicators should be based on clearly articulated environmental goals, with objectives and targets that are specific, measurable, achievable, relevant, and time bound.
... Nodules offer hard substrata in an otherwise soft sediment environment and host a specific nodule-associated fauna. More than 60% of megafauna depend on the nodules for attachment and survival (Amon et al., 2016;Vanreusel et al., 2016;Simon-Lledoé t al., 2019a). In order to be able to quantify the impact of potential deep-sea mining on nodule associated fauna, there is an urgent need for extensive ecological baselines to understand the natural biodiversity, variation (spatial and temporal) and possible resilience of fauna to mining impacts. ...
Introduction
Technological developments have facilitated the collection of large amounts of imagery from isolated deep-sea ecosystems such as abyssal nodule fields. Application of imagery as a monitoring tool in these areas of interest for deep-sea exploitation is extremely valuable. However, in order to collect a comprehensive number of species observations, thousands of images need to be analysed, especially if a high diversity is combined with low abundances such is the case in the abyssal nodule fields. As the visual interpretation of large volumes of imagery and the manual extraction of quantitative information is time-consuming and error-prone, computational detection tools may play a key role to lessen this burden. Yet, there is still no established workflow for efficient marine image analysis using deep learning–based computer vision systems for the task of fauna detection and classification.
Methods
In this case study, a dataset of 2100 images from the deep-sea polymetallic nodule fields of the eastern Clarion-Clipperton Fracture zone from the SO268 expedition (2019) was selected to investigate the potential of machine learning–assisted marine image annotation workflows. The Machine Learning Assisted Image Annotation method (MAIA), provided by the BIIGLE system, was applied to different set-ups trained with manually annotated fauna data. The results computed with the different set-ups were compared to those obtained by trained marine biologists regarding accuracy (i.e. recall and precision) and time.
Results
Our results show that MAIA can be applied for a general object (i.e. species) detection with satisfactory accuracy (90.1% recall and 13.4% precision), when considered as one intermediate step in a comprehensive annotation workflow. We also investigated the performance for different volumes of training data, MAIA performance tuned for individual morphological groups and the impact of sediment coverage in the training data.
Discussion
We conclude that: a) steps must be taken to enable computer vision scientists to access more image data from the CCZ to improve the system’s performance and b) computational species detection in combination with a posteriori filtering by marine biologists has a higher efficiency than fully manual analyses.
... Most of the fauna lives in the upper 5 cm of the sediment (Spiess et al. 1987;Smith and Demopoulos 2003) or even uses the nodules themselves as a habitat (Thiel et al. 1993;Veillette et al. 2007;Vanreusel et al. 2016;Drennan et al. 2021;Pape et al. 2021;Sanchez et al. 2022). The latter will be lost for the nodule-obligate biota following PMN extraction (Amon et al. 2016). In addition, sediment plumes of returned mining fines or collector-generated, whirled-up seafloor sediments have been modelled to travel well beyond the actual mining block (e.g. ...
... Such plumes, although much more localised than originally modelled without taking note of fluid dynamics and aggregation processes (e.g. Aleynik et al. 2017), will be detrimental to the sedentary epifauna (Amon et al. 2016;Vanreusel et al. 2016) and the thick layer of redeposition potentially harmful for the infauna. ...
The macrofauna in soft sediments of the deep seafloor is generally diverse and represents a comparatively well-studied faunal group of deep-sea ecosystems. In the abyss of the Clarion Clipperton Fracture Zone (CCFZ) in the NE Pacific, macrofauna are major contributors to benthic biodiversity. Their distribution, composition, and diversity have been frequently investigated to assess the potential impacts of future mining activities on the resident fauna. In this study, patterns of densities and community structure of CCFZ macrobenthic infauna and their relationships with a range of environmental and climatic variables were examined, with a special focus on communities from the eastern German contract area (referred to as BGR CA). However, comparisons were also made with other contractor areas (e.g., IFREMER, IOM, GSR) and one Area of Particular Environmental Interest (APEI3). Material for this study was obtained by means of a box corer during six expeditions to the CCFZ between 2013 and 2018 resulting in 148 samples. Our study uncovered notable spatial and temporal variations in both faunal densities and community composition. While areas within the BGR CA exhibited a similar community composition, slight differences were observed between the various CAs and APEI3. Surprisingly, we found an unexpected negative correlation between food availability and both macrofaunal density and community structure that may be attributed to differences in sampling methodologies and pronounced temporal variation. Furthermore, we explored the impact of climatic fluctuations associated with the El Niño/Southern Oscillation (ENSO) on macrofaunal densities, observing an increase during warm (El Niño) events. Our findings underscore the challenges of accurately assessing spatial and temporal variations in the absence of standardised sampling protocols. Hence, we emphasize the importance of adopting standardised protocols to enhance data comparability, thereby fostering a deeper understanding of the underlying factors influencing spatial and temporal changes in macrofauna community structure within the CCFZ.
... These giant agglutinated foraminifera are particularly common on seamounts and continental slopes, in submarine canyons, and on abyssal plains (Tendal & Gooday 1981; Levin and Thomas 1988;Bett 2001;Gooday et al. 2011). In the equatorial Pacific, they are a dominant group among the megafauna seen in seabed images across large areas of the Clarion-Clipperton Zone (CCZ), where they often outnumber all the metazoan megafauna combined (Kamenskaya et al., 2013;Amon et al., 2016;Simon-Lledó et al., 2019a, 2019bDurden et al. 2021;Uhlenkott et al., 2023). Although xenophyophores are typically the most common organisms visible on the deep ocean floor, they are difficult to incorporate into ecological studies. ...
Xenophyophores are large, agglutinated foraminifera that dominate the benthic megafauna in some parts of the deep sea. Here, we describe an assemblage of largely fragmentary specimens from the Clarion-Clipperton Zone (CCZ), an area of the eastern abyssal Pacific hosting large, commercially significant deposits of polymetallic nodules. We recognised 18 morphospecies of which eight yielded DNA sequences. These include two new genera and three new species, Claraclippia seminuda gen. & sp. nov., Stereodiktyoma mollis gen. & sp. nov., and Aschemonella tani sp. nov., three that are assigned to known species, Abyssalia foliformis, Aschemonella monilis and Shinkaiya contorta, and two assigned to open nomenclature forms Abyssalia aff. foliformis and Stannophyllum aff. granularium. An additional ten forms are represented only by morphology. The following seven are placed in known genera, species and open-nomenclature forms: Aschemonella? sp., Homogammina sp., Psammina multiloculata, P. aff. multiloculata, P. aff. limbata form 1 sensu Gooday et al., 2018, P. aff. limbata form 2 sensu Gooday et al., 2018, and Stannophyllum spp. The other three could not be identified to genus level. This new collection brings the total of described and undescribed species and morphotypes from the CCZ to 27 and 70, respectively, reinforcing the already high diversity of xenophyophores known from this part of the Pacific.
... Although areas of potentially commercially viable nodule abundances are known, commercial extraction has yet to commence, though experimental works with nodule-gathering vehicles and on investigating the potential disturbance impacts on seafloor structure and communities are ongoing. The topic remains controversial as it is assumed that mining will have negative impacts on the deep-sea ecosystem, at least on the local scale, with the hard substrate provided by the nodules being wholly removed from the seafloor/ ocean interface (Amon et al. 2016;Jones et al. 2017;Stratmann et al. 2018;Smith et al. 2020). In general, soft sediments form much of this interface across the abyssal plains, though in regions where polymetallic nodules occur, these nodules provide a hard substrate, creating a complex which supports a highly diverse range of sessile fauna (Vanreusel et al. 2016), as well as adding complexity to the local hydrodynamic regime on the local scale. ...
Interest in deep-sea mining for polymetallic nodules as an alternative source to onshore mines for various high-technology metals has risen in recent years, as demands and costs have increased. The need for studies to assess its short- and long-term consequences on polymetallic nodule ecosystems is therefore also increasingly prescient. Recent image-based expedition studies have described the temporal impacts on epi-/megafauna seafloor communities across these ecosystems at particular points in time. However, these studies have failed to capture information on large infauna within the sediments or give information on potential transient and temporally limited users of these areas, such as mobile surface deposit feeders or fauna responding to bloom events or food fall depositions. This study uses data from the Peru Basin polymetallic nodule province, where the seafloor was previously disturbed with a plough harrow in 1989 and with an epibenthic sled (EBS) in 2015, to simulate two contrasting possible impact forms of mining disturbance. To try and address the shortfall on information on transient epifauna and infauna use of these various disturbed and undisturbed areas of nodule-rich seafloor, images collected 6 months after the 2015 disturbance event were inspected and all Lebensspuren , ‘traces of life’, were characterized by type (epi- or infauna tracemakers, as well as forming fauna species where possible), along with whether they occurred on undisturbed seafloor or regions disturbed in 1989 or 2015. The results show that epi- and endobenthic Lebensspuren were at least 50% less abundant across both the ploughed and EBS disturbed seafloors. This indicates that even 26 years after disturbance, sediment use by fauna may remain depressed across these areas.
... Among them, O.cf.glabrum is a very typical Ophiuroid species in the deep-sea environment. Amon et al. (2016) also reported that this species was present at all sampling sites in the CCZ area. In contrast to the widespread species, some meiofauna taxa (e.g., Platyhelminthes, Xenacoelomorpha, and Nemertea, Figure 3A) displayed patchy distributions and were found in random stations. ...
Trench-arc-basin (TAB) systems are widely distributed in the deep sea, yet our understanding of their biodiversity patterns and community assemblages remains limited. In this study, we collected sediment samples from 22 stations across a Western Pacific TAB system and identified 85 families of marine benthos from 15 phyla by using eDNA metabarcoding with the 18S rRNA gene V4 region. Nematodes were the most dominant metazoan taxa followed by echinoderms, arthropods, and annelids. The highest biodiversity and species specificity were observed at stations located near seamounts. The community assemblages were highly heterogeneous in this TAB system, likely induced by the large geographic barriers and the high habitat heterogeneity. Furthermore, the total organic carbon content and median grain size of the sediment drive the overall community composition, and the water depth exerts a significant influence on species richness and abundance. Our results provide insight into benthos diversity and distribution across a TAB system and data for further comparisons and modeling studies.
... Although they analysed polychaetes mostly at the family level, this localscale study was able to reveal a positive significant relationship between polychaete abundance and nodule densities (supported by Bonifácio et al. 2020 but not by Washburn et al. 2021a). This positive relationship is best known for sessile mega-and macrofauna requiring hard substrate for settling (Mullineaux 1987;Vanreusel et al. 2016;Amon et al. 2016). For example, Vanreusel et al. (2016) observed mega-epifaunal densities more than twice as high in nodule-rich areas, with some taxa (e.g. ...
The deep seafloor of the Northeastern Pacific Ocean between the Clarion and Clipperton Fracture Zones (CCZ) hosts large deposits of polymetallic nodules that are of great commercial interest as they are rich in valuable metals such as manganese, nickel, copper and cobalt. However, mining of these nodules has the potential to severely affect the benthic fauna, whose distribution and diversity are still poorly understood. The CCZ is characterized by strong gradients in sea surface productivity and hence changes in the amount of organic carbon reaching the seafloor, decreasing from mesotrophic conditions in the southeast to oligotrophic conditions in the northwest. Uncovering and understanding changes in community composition and structure along this productivity gradient are challenging but important, especially in the context of future mining impacts. Here, we summarize published data on benthic annelids (polychaetes), a major component of macrobenthic communities in the CCZ. Unlike previous studies, we attempt to explore all available data based on both morphology and genetics collected by box corer and epibenthic sledge. In this regard, we specifically aimed to (a) summarize and compare morphological and molecular data in relation to surface water nutrient conditions and (b) provide recommendations to advance the studies of polychaete biodiversity. Although initial studies on polychaetes in the CCZ were performed as far back as the 1970s, there are still large data gaps further explored in our review. For example, most of the current data are from the eastern CCZ, limiting understanding of species ranges across the region. An association between polychaete communities and the available food supply was generally observed in this study. Indeed, mesotrophic conditions supported higher abundance and species richness in polychaetes as a whole, but for certain groups of species, the patterns appear to be opposite — illustrating that relationships are likely more complex at lower taxonomic levels. A better understanding of biogeographical, ecological and evolutionary processes requires a concerted effort involving increased sampling and sharing of data and material to close existing knowledge gaps.
... However, these methods face challenges when processing complex thyroid nodule images, such as unstable image quality and diversity in nodule shape and density [14]. To address these issues, researchers have begun exploring deep-learning methods to facilitate thyroid nodule image localization and classification performance. ...
Aim
This study aims to establish an artificial intelligence model, ThyroidNet, to diagnose thyroid nodules using deep learning techniques accurately.
Methods
A novel method, ThyroidNet, is introduced and evaluated based on deep learning for the localization and classification of thyroid nodules. First, we propose the multitask TransUnet, which combines the TransUnet encoder and decoder with multitask learning. Second, we propose the DualLoss function, tailored to the thyroid nodule localization and classification tasks. It balances the learning of the localization and classification tasks to help improve the model’s generalization ability. Third, we introduce strategies for augmenting the data. Finally, we submit a novel deep learning model, ThyroidNet, to accurately detect thyroid nodules.
Results
ThyroidNet was evaluated on private datasets and was comparable to other existing methods, including U-Net and TransUnet. Experimental results show that ThyroidNet outperformed these methods in localizing and classifying thyroid nodules. It achieved improved accuracy of 3.9% and 1.5%, respectively.
Conclusion
ThyroidNet significantly improves the clinical diagnosis of thyroid nodules and supports medical image analysis tasks. Future research directions include optimization of the model structure, expansion of the dataset size, reduction of computational complexity and memory requirements, and exploration of additional applications of ThyroidNet in medical image analysis.
... Nodule mining will cause loss of essential habitats, including the structural habitat required by some faunal groups (Amon et al., 2016;Vanreusel et al., 2016;Leitner et al., 2017;Stratmann et al., 2021). This type of strip-mining will also substantially and persistently impact food web integrity, i.e. through loss of nodules as a structural habitat for ecological keystone taxa, such as stalked sponges (Stratmann et al., 2021). ...
Best environmental practice (BEP) is a key component of an ecosystem approach to management and is typically a product of practical experience in established industries. For an emerging activity such as deep seabed mining, no such experience will exist at the time of deciding on the permissibility of the first industrial mines. Therefore, experience from deep ocean scientific experiments and research are important to develop a preliminary understanding of BEP for deep seabed mining. This paper offers a detailed review of the scientific literature from which it identifies elements of preliminary BEP for nodule mining. The paper describes the currently envisaged mining process for manganese nodules and its expected effects on the environment and extracts specific recommendations on how to minimise environmental impacts from mining in different layers of the ocean (benthic, benthopelagic, pelagic, and surface waters) as well as from noise and light impacts. In doing so, the paper aims to inform the Mining Code being developed by the International Seabed Authority (ISA). The ISA is the intergovernmental institution mandated to organise and control seabed mining on the international seabed. The ISA is obligated to ensure effective protection of the marine environment from harm likely to arise from mining, with BEP being a core tool to achieve that. This paper provides suggestions for a future ISA Standard on BEP.
