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Clark HP, Smith AG, McKay Fletcher D, Larsson AI, Jaspars M, De Clippele LH. New interactive machine learning tool for marine image analysis. ROYAL SOCIETY OPEN SCIENCE 2024; 11:231678. [PMID: 39157716 PMCID: PMC11328963 DOI: 10.1098/rsos.231678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 03/28/2024] [Accepted: 04/02/2024] [Indexed: 08/20/2024]
Abstract
Advancing imaging technologies are drastically increasing the rate of marine video and image data collection. Often these datasets are not analysed to their full potential as extracting information for multiple species is incredibly time-consuming. This study demonstrates the capability of the open-source interactive machine learning tool, RootPainter, to analyse large marine image datasets quickly and accurately. The ability of RootPainter to extract the presence and surface area of the cold-water coral reef associate sponge species, Mycale lingua, was tested in two datasets: 18 346 time-lapse images and 1420 remotely operated vehicle video frames. New corrective annotation metrics integrated with RootPainter allow objective assessment of when to stop model training and reduce the need for manual model validation. Three highly accurate M. lingua models were created using RootPainter, with an average dice score of 0.94 ± 0.06. Transfer learning aided the production of two of the models, increasing analysis efficiency from 6 to 16 times faster than manual annotation for time-lapse images. Surface area measurements were extracted from both datasets allowing future investigation of sponge behaviours and distributions. Moving forward, interactive machine learning tools and model sharing could dramatically increase image analysis speeds, collaborative research and our understanding of spatiotemporal patterns in biodiversity.
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Affiliation(s)
- H. Poppy Clark
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, AberdeenAB24 3UE, UK
| | - Abraham George Smith
- Department of Computer Science, University of Copenhagen, Copenhagen2100, Denmark
| | - Daniel McKay Fletcher
- Rural Economy, Environment and Society, Scotland’s Rural College, EdinburghEH9 3JG, UK
| | - Ann I. Larsson
- Tjärnö Marine Laboratory, Department of Marine Sciences, University of Gothenburg, Sweden
| | - Marcel Jaspars
- Marine Biodiscovery Centre, Department of Chemistry, University of Aberdeen, AberdeenAB24 3UE, UK
| | - Laurence H. De Clippele
- School of Biodiversity, One Health & Veterinary Medicine, University of Glasgow, GlasgowG61 1QH, UK
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2
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Stratmann T, Simon-Lledó E, Morganti TM, de Kluijver A, Vedenin A, Purser A. Habitat types and megabenthos composition from three sponge-dominated high-Arctic seamounts. Sci Rep 2022; 12:20610. [PMID: 36446839 PMCID: PMC9708660 DOI: 10.1038/s41598-022-25240-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
Seamounts are isolated underwater mountains stretching > 1000 m above the seafloor. They are identified as biodiversity hotspots of marine life, and host benthic assemblages that may vary on regional (among seamounts) and local (within seamounts) scales. Here, we collected seafloor imagery of three seamounts at the Langseth Ridge in the central Arctic Ocean to assess habitats and megabenthos community composition at the Central Mount (CM), the Karasik Seamount (KS), and the Northern Mount (NM). The majority of seafloor across these seamounts comprised bare rock, covered with a mixed layer of sponge spicule mats intermixed with detrital debris composed of polychaete tubes, and sand, gravel, and/or rocks. The megabenthos assemblages consisted of in total 15 invertebrate epibenthos taxa and 4 fish taxa, contributing to mean megabenthos densities of 55,745 ind. ha-1 at CM, 110,442 ind. ha-1 at KS, and 65,849 ind. ha-1 at NM. The faunal assemblages at all three seamounts were dominated by habitat-forming Tetractinellida sponges that contributed between 66% (KS) and 85% (CM) to all megabenthos. Interestingly, taxa richness did not differ at regional and local scale, whereas the megabenthos community composition did. Abiotic and biogenic factors shaping distinct habitat types played a major role in structuring of benthic communities in high-Arctic seamounts.
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Affiliation(s)
- Tanja Stratmann
- grid.5477.10000000120346234Department of Earth Sciences, Utrecht University, Vening Meineszgebouw A, Princetonlaan 8, 3584 CB Utrecht, The Netherlands ,grid.419529.20000 0004 0491 3210HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany ,grid.10914.3d0000 0001 2227 4609Department of Ocean Systems, NIOZ – Royal Netherlands Institute for Sea Research, Landsdiep 4, 1797 SZ ‘t Horntje (Texel), The Netherlands
| | - Erik Simon-Lledó
- grid.418022.d0000 0004 0603 464XOcean BioGeosciences, National Oceanography Centre, European Way, Southampton, SO14 3ZH UK
| | - Teresa Maria Morganti
- grid.419529.20000 0004 0491 3210HGF MPG Joint Research Group for Deep-Sea Ecology and Technology, Max Planck Institute for Marine Microbiology, Celsiusstraße 1, 28359 Bremen, Germany ,grid.423940.80000 0001 2188 0463Marine Chemistry Department, Leibniz Institute for Baltic Sea Research Warnemünde, Seestraße 15, 18119 Rostock, Germany
| | - Anna de Kluijver
- grid.5477.10000000120346234Department of Earth Sciences, Utrecht University, Vening Meineszgebouw A, Princetonlaan 8, 3584 CB Utrecht, The Netherlands
| | - Andrey Vedenin
- grid.500026.10000 0004 0487 6958Marine Biology Section, Senckenberg am Meer, Südstrand 40, 26382 Wilhelmshaven, Germany
| | - Autun Purser
- grid.10894.340000 0001 1033 7684Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Am Handelshafen 12, 27570 Bremerhaven, Germany
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3
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Corbera G, Lo Iacono C, Simarro G, Grinyó J, Ambroso S, Huvenne VAI, Mienis F, Carreiro-Silva M, Martins I, Mano B, Orejas C, Larsson A, Hennige S, Gori A. Local-scale feedbacks influencing cold-water coral growth and subsequent reef formation. Sci Rep 2022; 12:20389. [PMID: 36437278 PMCID: PMC9701764 DOI: 10.1038/s41598-022-24711-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Accepted: 11/18/2022] [Indexed: 11/29/2022] Open
Abstract
Despite cold-water coral (CWC) reefs being considered biodiversity hotspots, very little is known about the main processes driving their morphological development. Indeed, there is a considerable knowledge gap in quantitative experimental studies that help understand the interaction between reef morphology, near-bed hydrodynamics, coral growth, and (food) particle transport processes. In the present study, we performed a 2-month long flume experiment in which living coral nubbins were placed on a reef patch to determine the effect of a unidirectional flow on the growth and physiological condition of Lophelia pertusa. Measurements revealed how the presence of coral framework increased current speed and turbulence above the frontal part of the reef patch, while conditions immediately behind it were characterised by an almost stagnant flow and reduced turbulence. Owing to the higher current speeds that likely promoted a higher food encounter rate and intake of ions involved in the calcification process, the coral nubbins located on the upstream part of the reef presented a significantly enhanced average growth and a lower expression of stress-related enzymes than the downstream ones. Yet, further experiments would be needed to fully quantify how the variations in water hydrodynamics modify particle encounter and ion intake rates by coral nubbins located in different parts of a reef, and how such discrepancies may ultimately affect coral growth. Nonetheless, the results acquired here denote that a reef influenced by a unidirectional water flow would grow into the current: a pattern of reef development that coincides with that of actual coral reefs located in similar water flow settings. Ultimately, the results of this study suggest that at the local scale coral reef morphology has a direct effect on coral growth thus, indicating that the spatial patterns of living CWC colonies in reef patches are the result of spatial self-organisation.
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Affiliation(s)
- Guillem Corbera
- grid.4711.30000 0001 2183 4846Institut de Ciències del Mar, CSIC, Barcelona, Spain ,grid.5491.90000 0004 1936 9297University of Southampton, Southampton, UK ,grid.418022.d0000 0004 0603 464XNational Oceanography Centre, Southampton, UK
| | - Claudio Lo Iacono
- grid.4711.30000 0001 2183 4846Institut de Ciències del Mar, CSIC, Barcelona, Spain
| | - Gonzalo Simarro
- grid.4711.30000 0001 2183 4846Institut de Ciències del Mar, CSIC, Barcelona, Spain
| | - Jordi Grinyó
- grid.4711.30000 0001 2183 4846Institut de Ciències del Mar, CSIC, Barcelona, Spain ,grid.10914.3d0000 0001 2227 4609Royal Netherlands Institute for Sea Research (NIOZ), Texel, The Netherlands
| | - Stefano Ambroso
- grid.4711.30000 0001 2183 4846Institut de Ciències del Mar, CSIC, Barcelona, Spain
| | - Veerle A. I. Huvenne
- grid.418022.d0000 0004 0603 464XNational Oceanography Centre, Southampton, UK ,grid.484198.80000 0001 0659 5066Hanse-Wissenschaftskolleg – Institute for Advanced Study (HWK), Lehmkuhlenbusch 4, 27753 Delmenhorst, Germany
| | - Furu Mienis
- grid.10914.3d0000 0001 2227 4609Royal Netherlands Institute for Sea Research (NIOZ), Texel, The Netherlands
| | - Marina Carreiro-Silva
- grid.7338.f0000 0001 2096 9474Institute of Marine Research-Okeanos, University of Azores, Ponta Delgada, Portugal
| | - Inês Martins
- grid.7338.f0000 0001 2096 9474Institute of Marine Research-Okeanos, University of Azores, Ponta Delgada, Portugal
| | - Beatriz Mano
- grid.7338.f0000 0001 2096 9474Institute of Marine Research-Okeanos, University of Azores, Ponta Delgada, Portugal
| | - Covadonga Orejas
- grid.410389.70000 0001 0943 6642Centro Oceanográfico de Gijón, Instituto Español de Oceanografía (IEO-CSIC), Avenida Príncipe de Asturias 70 Bis, 33212 Gijón, Spain ,grid.484198.80000 0001 0659 5066Hanse-Wissenschaftskolleg – Institute for Advanced Study (HWK), Lehmkuhlenbusch 4, 27753 Delmenhorst, Germany
| | - Ann Larsson
- grid.8761.80000 0000 9919 9582University of Gothenburg, Gothenburg, Sweden
| | - Sebastian Hennige
- grid.4305.20000 0004 1936 7988School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - Andrea Gori
- grid.4711.30000 0001 2183 4846Institut de Ciències del Mar, CSIC, Barcelona, Spain ,grid.9906.60000 0001 2289 7785Università del Salento, Lecce, Italy ,grid.5841.80000 0004 1937 0247Universitat de Barcelona, Barcelona, Spain
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Environmental stability and phenotypic plasticity benefit the cold-water coral Desmophyllum dianthus in an acidified fjord. Commun Biol 2022; 5:683. [PMID: 35810196 PMCID: PMC9271058 DOI: 10.1038/s42003-022-03622-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Accepted: 06/22/2022] [Indexed: 11/13/2022] Open
Abstract
The stratified Chilean Comau Fjord sustains a dense population of the cold-water coral (CWC) Desmophyllum dianthus in aragonite supersaturated shallow and aragonite undersaturated deep water. This provides a rare opportunity to evaluate CWC fitness trade-offs in response to physico-chemical drivers and their variability. Here, we combined year-long reciprocal transplantation experiments along natural oceanographic gradients with an in situ assessment of CWC fitness. Following transplantation, corals acclimated fast to the novel environment with no discernible difference between native and novel (i.e. cross-transplanted) corals, demonstrating high phenotypic plasticity. Surprisingly, corals exposed to lowest aragonite saturation (Ωarag < 1) and temperature (T < 12.0 °C), but stable environmental conditions, at the deep station grew fastest and expressed the fittest phenotype. We found an inverse relationship between CWC fitness and environmental variability and propose to consider the high frequency fluctuations of abiotic and biotic factors to better predict the future of CWCs in a changing ocean. The cold-water coral Desmophyllum dianthus benefits from stable environmental conditions in deep waters of Comau Fjord (Chile) and is able to acclimatise quickly to new environmental conditions after transplantation.
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Portilho-Ramos RDC, Titschack J, Wienberg C, Siccha Rojas MG, Yokoyama Y, Hebbeln D. Major environmental drivers determining life and death of cold-water corals through time. PLoS Biol 2022; 20:e3001628. [PMID: 35587463 PMCID: PMC9119455 DOI: 10.1371/journal.pbio.3001628] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 04/12/2022] [Indexed: 11/24/2022] Open
Abstract
Cold-water corals (CWCs) are the engineers of complex ecosystems forming unique biodiversity hotspots in the deep sea. They are expected to suffer dramatically from future environmental changes in the oceans such as ocean warming, food depletion, deoxygenation, and acidification. However, over the last decades of intense deep-sea research, no extinction event of a CWC ecosystem is documented, leaving quite some uncertainty on their sensitivity to these environmental parameters. Paleoceanographic reconstructions offer the opportunity to align the on- and offsets of CWC proliferation to environmental parameters. Here, we present the synthesis of 6 case studies from the North Atlantic Ocean and the Mediterranean Sea, revealing that food supply controlled by export production and turbulent hydrodynamics at the seabed exerted the strongest impact on coral vitality during the past 20,000 years, whereas locally low oxygen concentrations in the bottom water can act as an additional relevant stressor. The fate of CWCs in a changing ocean will largely depend on how these oceanographic processes will be modulated. Future ocean deoxygenation may be compensated regionally where the food delivery and food quality are optimal.
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Affiliation(s)
| | - Jürgen Titschack
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
- Senckenberg am Meer, Marine Research Department, Wilhelmshaven, Germany
| | - Claudia Wienberg
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
| | | | - Yusuke Yokoyama
- Analytical Center for Environmental Science–Atmosphere and Ocean Research Institute, University of Tokyo, Tokyo, Japan
| | - Dierk Hebbeln
- MARUM–Center for Marine Environmental Sciences, University of Bremen, Bremen, Germany
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6
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Raddatz J, Liebetrau V, Rüggeberg A, Foubert A, Flögel S, Nürnberg D, Hissmann K, Musiol J, Goepfert TJ, Eisenhauer A, Dullo WC. Living on the edge: environmental variability of a shallow late Holocene cold-water coral mound. CORAL REEFS (ONLINE) 2022; 41:1255-1271. [PMID: 35912336 PMCID: PMC9325858 DOI: 10.1007/s00338-022-02249-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2021] [Accepted: 03/19/2022] [Indexed: 06/01/2023]
Abstract
UNLABELLED Similar to their tropical counterparts, cold-water corals (CWCs) are able to build large three-dimensional reef structures. These unique ecosystems are at risk due to ongoing climate change. In particular, ocean warming, ocean acidification and changes in the hydrological cycle may jeopardize the existence of CWCs. In order to predict how CWCs and their reefs or mounds will develop in the near future one important strategy is to study past fossil CWC mounds and especially shallow CWC ecosystems as they experience a greater environmental variability compared to other deep-water CWC ecosystems. We present results from a CWC mound off southern Norway. A sediment core drilled from this relatively shallow (~ 100 m) CWC mound exposes in full detail hydrographical changes during the late Holocene, which were crucial for mound build-up. We applied computed tomography, 230Th/U dating, and foraminiferal geochemical proxy reconstructions of bottom-water-temperature (Mg/Ca-based BWT), δ18O for seawater density, and the combination of both to infer salinity changes. Our results demonstrate that the CWC mound formed in the late Holocene between 4 kiloannum (ka) and 1.5 ka with an average aggradation rate of 104 cm/kiloyears (kyr), which is significantly lower than other Holocene Norwegian mounds. The reconstructed BWTMg/Ca and seawater density exhibit large variations throughout the entire period of mound formation, but are strikingly similar to modern in situ observations in the nearby Tisler Reef. We argue that BWT does not exert a primary control on CWC mound formation. Instead, strong salinity and seawater density variation throughout the entire mound sequence appears to be controlled by the interplay between the Atlantic Water (AW) inflow and the overlying, outflowing Baltic-Sea water. CWC growth and mound formation in the NE Skagerrak was supported by strong current flow, oxygen replenishment, the presence of a strong boundary layer and larval dispersal through the AW, but possibly inhibited by the influence of fresh Baltic Water during the late Holocene. Our study therefore highlights that modern shallow Norwegian CWC reefs may be particularly endangered due to changes in water-column stratification associated with increasing net precipitation caused by climate change. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s00338-022-02249-4.
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Affiliation(s)
- Jacek Raddatz
- Institute of Geosciences, Goethe University Frankfurt, Altenhöferallee 1, 60438 Frankfurt, Germany
| | - Volker Liebetrau
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
| | - Andres Rüggeberg
- Department of Geosciences, University of Fribourg, Chemin du Musée 6, 1700 Fribourg, Switzerland
| | - Anneleen Foubert
- Department of Geosciences, University of Fribourg, Chemin du Musée 6, 1700 Fribourg, Switzerland
| | - Sascha Flögel
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
| | - Dirk Nürnberg
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
| | - Karen Hissmann
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
| | - Johannes Musiol
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
| | - Tyler Jay Goepfert
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
- Present Address: School of Earth & Space Exploration, Arizona State University, Tempe, AZ 85287-1404 USA
| | - Anton Eisenhauer
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
| | - Wolf-Christian Dullo
- GEOMAR Helmholtz Centre for Ocean Research Kiel, Wischhofstr. 1-3, 24148 Kiel, Germany
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7
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Sanna G, Freiwald A. Deciphering the composite morphological diversity of
Lophelia pertusa
, a cosmopolitan deep‐water ecosystem engineer. Ecosphere 2021. [DOI: 10.1002/ecs2.3802] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
Affiliation(s)
- Giovanni Sanna
- Marine Research Department Senckenberg am Meer Wilhelmshaven 26382 Germany
- Faculty of Geosciences University of Bremen Bremen 28359 Germany
- MARUM—Center for Marine Environmental Sciences University of Bremen Bremen 28359 Germany
| | - André Freiwald
- Marine Research Department Senckenberg am Meer Wilhelmshaven 26382 Germany
- Faculty of Geosciences University of Bremen Bremen 28359 Germany
- MARUM—Center for Marine Environmental Sciences University of Bremen Bremen 28359 Germany
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8
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Hennige SJ, Larsson AI, Orejas C, Gori A, De Clippele LH, Lee YC, Jimeno G, Georgoulas K, Kamenos NA, Roberts JM. Using the Goldilocks Principle to model coral ecosystem engineering. Proc Biol Sci 2021; 288:20211260. [PMID: 34375552 PMCID: PMC8354746 DOI: 10.1098/rspb.2021.1260] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The occurrence and proliferation of reef-forming corals is of vast importance in terms of the biodiversity they support and the ecosystem services they provide. The complex three-dimensional structures engineered by corals are comprised of both live and dead coral, and the function, growth and stability of these systems will depend on the ratio of both. To model how the ratio of live : dead coral may change, the ‘Goldilocks Principle’ can be used, where organisms will only flourish if conditions are ‘just right’. With data from particle imaging velocimetry and numerical smooth particle hydrodynamic modelling with two simple rules, we demonstrate how this principle can be applied to a model reef system, and how corals are effectively optimizing their own local flow requirements through habitat engineering. Building on advances here, these approaches can be used in conjunction with numerical modelling to investigate the growth and mortality of biodiversity supporting framework in present-day and future coral reef structures.
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Affiliation(s)
- S J Hennige
- Changing Oceans Group, School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - A I Larsson
- Department of Marine Sciences, Tjärnö Marine Laboratory, University of Gothenburg, Gothenburg, Sweden
| | - C Orejas
- Instituto Español de Oceanografía, Centro Oceanográfico de Gijón, IEO, CSIC, Gijón, Spain
| | - A Gori
- Departament de Biologia Evolutiva, Ecologia i Ciències Ambientals, Universitat de Barcelona, Barcelona, Spain
| | - L H De Clippele
- Changing Oceans Group, School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - Y C Lee
- School of Engineering, Computing and Mathematics, University of Plymouth, Devon, UK
| | - G Jimeno
- School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - K Georgoulas
- Changing Oceans Group, School of GeoSciences, University of Edinburgh, Edinburgh, UK
| | - N A Kamenos
- School of Geographical and Earth Sciences, University of Glasgow, Glasgow, UK
| | - J M Roberts
- Changing Oceans Group, School of GeoSciences, University of Edinburgh, Edinburgh, UK
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9
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A Fluid Dynamics Approach for Assessing the Intelligent Geomorphic Design of the Japanese Pufferfish Nest. GEOSCIENCES 2021. [DOI: 10.3390/geosciences11010022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Research into the geometric nests built by white-spotted pufferfish indicated the nest’s potential for flow control and reduction in flow velocity. However, studies to date have only focused on the construction process and behaviour of the male pufferfish. Hence, the form and functions of the unique features of the nest remain unclear. The present study aims to explore the flow features most useful in understanding the habitat conditions of the nest through a combination of photogrammetric reconstructions of the nest features and two-dimensional (2D) computational fluid dynamic simulations. The findings show the role of the nest structure in reducing the flow velocity and shear stress within the nesting site. Analysis of shear stress indicates that male pufferfish build the outer zones of the nest with coarser material that improves the overall shear strength of these areas. The study identified the function of the nest structure in the protection of the eggs through reduction in flow variations and improved aeration. The addition of shell fragments to the nest peaks by the male pufferfish contributes to the resiliency of the nest structure and ensures a stable bed surface at the central zone.
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10
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Cold-Water Coral Habitat Mapping: Trends and Developments in Acquisition and Processing Methods. GEOSCIENCES 2020. [DOI: 10.3390/geosciences11010009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Cold-water coral (CWC) habitats are considered important centers of biodiversity in the deep sea, acting as spawning grounds and feeding area for many fish and invertebrates. Given their occurrence in remote parts of the planet, research on CWC habitats has largely been derived from remotely-sensed marine spatial data. However, with ever-developing marine data acquisition and processing methods and non-ubiquitous nature of infrastructure, many studies are completed in isolation resulting in large inconsistencies. Here, we present a concise review of marine remotely-sensed spatial raster data acquisition and processing methods in CWC habitats to highlight trends and knowledge gaps. Sixty-three studies that acquire and process marine spatial raster data since the year 2000 were reviewed, noting regional geographic location, data types (‘acquired data’) and how the data were analyzed (‘processing methods’). Results show that global efforts are not uniform with most studies concentrating in the NE Atlantic. Although side scan sonar was a popular mapping method between 2002 and 2012, since then, research has focused on the use of multibeam echosounder and photogrammetric methods. Despite advances in terrestrial mapping with machine learning, it is clear that manual processing methods are largely favored in marine mapping. On a broader scale, with large-scale mapping programs (INFOMAR, Mareano, Seabed2030), results from this review can help identify where more urgent research efforts can be concentrated for CWC habitats and other vulnerable marine ecosystems.
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11
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Influence of benthic currents on cold-water coral habitats: a combined benthic monitoring and 3D photogrammetric investigation. Sci Rep 2020; 10:19433. [PMID: 33173079 PMCID: PMC7655950 DOI: 10.1038/s41598-020-76446-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Accepted: 10/29/2020] [Indexed: 01/12/2023] Open
Abstract
Strong currents are a key component of benthic habitats by supplying food and nutrients to filter-feeding organisms such as cold-water corals. Although field measurements show that cold-water coral habitats exist in areas of elevated bottom currents, flume studies show that cold-water corals feed more effectively at lower flow speeds. This research aims to explore this disconnect in situ by utilising high spatial resolution ROV photogrammetric data coupled with high temporal resolution in situ acoustic doppler current profile measurements at seven study sites within the upper Porcupine Bank Canyon (uPBC), NE Atlantic. Object-based image analysis of photogrammetric data show that coral habitats vary considerably within the upper canyon. Although there is a regional hydrodynamic trend across the uPBC, this variation is likely driven locally by topographic steering. Although live coral tends not to face directly into the prevailing current direction, preferring lower local flows speeds, they can tolerate exposure to high-flow speeds of up to 114 cm s-1, the highest recorded in a Desmophyllum pertusum habitat. Not only do these high flow speeds supply food and nutrients, they may also help contribute to coral rubble production through physical erosion. These results can be incorporated into simulations of future deep-water habitat response to changing environmental conditions while extending the upper current speed threshold for cold-water corals.
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12
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Goode SL, Rowden AA, Bowden DA, Clark MR. Resilience of seamount benthic communities to trawling disturbance. MARINE ENVIRONMENTAL RESEARCH 2020; 161:105086. [PMID: 32889447 DOI: 10.1016/j.marenvres.2020.105086] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2020] [Revised: 07/06/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
Despite bottom trawling being the most widespread, severe disturbance affecting deep-sea environments, it remains uncertain whether recovery is possible once trawling has ceased. Here, we review information regarding the resilience of seamount benthic communities to trawling. We focus on seamounts because benthic communities associated with these features are especially vulnerable to trawling as they are often dominated by emergent, sessile epifauna, and trawling on seamounts can be highly concentrated. We perform a meta-analysis to investigate whether any taxa demonstrate potential for recovery once trawling has ceased. Our findings indicate that mean total abundance can gradually increase after protection measures are placed, although taxa exhibit various responses, from no recovery to intermediate/high recovery, resistance, or signs of early colonisation. We use our results to recommend directions for future research to improve our understanding of the resilience of seamount benthic communities, and thereby inform the management of trawling impacts on these ecosystems.
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Affiliation(s)
- Savannah L Goode
- National Institute of Water and Atmospheric Research, Wellington, New Zealand; Victoria University of Wellington, Wellington, New Zealand.
| | - Ashley A Rowden
- National Institute of Water and Atmospheric Research, Wellington, New Zealand; Victoria University of Wellington, Wellington, New Zealand
| | - David A Bowden
- National Institute of Water and Atmospheric Research, Wellington, New Zealand
| | - Malcolm R Clark
- National Institute of Water and Atmospheric Research, Wellington, New Zealand
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Plasticity in Three-Dimensional Geometry of Branching Corals Along a Cross-Shelf Gradient. DIVERSITY 2019. [DOI: 10.3390/d11030044] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Scleractinian corals often exhibit high levels of morphological plasticity, which is potentially important in enabling individual species to occupy benthic spaces across a wide range of environmental gradients. This study tested for differences in the three-dimensional (3D) geometry of three branching corals, Acropora nasuta, Pocillopora spp. and Stylophora pistillata among inner-, mid- and outer-shelf reefs in the central Great Barrier Reef, Australia. Important attributes of coral morphology (e.g., surface area to volume ratio) were expected to vary linearly across the shelf in accordance with marked gradients in environmental conditions, but instead, we detected non-linear trends in the colony structure of A. nasuta and Pocillopora spp. The surface area to volume ratio of both A. nasuta and Pocillopora spp. was highest at mid-shelf locations, (reflecting higher colony complexity) and was significantly lower at both inner-shelf and outer-shelf reefs. The branching structure of these corals was also far more tightly packed at inner-shelf and outer-shelf reefs, compared to mid-shelf reefs. Apparent declines in complexity and inter-branch spacing at inner and outer-shelf reefs (compared to conspecifics from mid-shelf reefs) may reflect changes driven by gradients of sedimentation and hydrodynamics. The generality and explanations of observed patterns warrant further investigation, which is very feasible using the 3D-photogrammetry techniques used in this study.
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