Thomas G. Dahlgren's research while affiliated with University of Gothenburg and other places

Publications (194)

Article
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The deep ocean comprises complex ecosystems made up of numerous community and habitat types that provide multiple services that benefit humans. As the industrialization of the deep sea proceeds, a standardized and robust set of methods and metrics need to be developed to monitor the baseline conditions and any anthropogenic and climate change-relat...
Article
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After nearly 30 years of experience with offshore wind energy (OWE), the industry is moving past the initial learning phase and into large-scale development. One of the strongest motivations for OWE is that projects are large enough to replace fossil-fueled electricity production that we know is a primary contributor to the ongoing climate crisis....
Article
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This is a contribution in a series of taxonomic publications on benthic fauna of polymetallic nodule fields in the eastern abyssal Clarion-Clipperton Zone (CCZ). The material was collected during environmental surveys targeting exploration contract areas ‘UK-1’, ‘OMS’ and ‘NORI-D’, as well as an Area of Particular Environmental Interest, ‘APEI-6’....
Article
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This paper represents a continuation of taxonomic publications on the benthic fauna of polymetallic nodule fields in the eastern Clarion-Clipperton Zone (CCZ) using material collected during baseline environmental survey work targeting two exploration contract areas (“UK-1” and “OMS”) and one Area of Particular Environmental Interest, “APEI-6.” Fam...
Article
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There is a growing interest in the exploitation of deep-sea mineral deposits, particularly on the abyssal seafloor of the central Pacific Clarion-Clipperton Zone (CCZ), which is rich in polymetallic nodules. In order to effectively manage potential exploitation activities, a thorough understanding of the biodiversity, community structure, species r...
Article
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Apart from its contribution to climate change, offshore oil and gas extraction is also a potential threat to the diversity and function of marine ecosystems. Routine monitoring of the environmental status of affected areas is therefore critical for effective management. While current morphology-based monitoring is relatively time consuming, costly...
Article
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Many microorganisms feed on the tissue and recalcitrant bone materials from dead animals, however little is known about the collaborative effort and characteristics of their enzymes. In this study, microbial metagenomes from symbionts of the marine bone-dwelling worm Osedax mucofloris, and from microbial biofilms growing on experimentally deployed...
Article
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A new species of abyssal Neanthes Kinberg, 1865, N. goodayi sp. nov., is described from the Clarion-Clipperton Zone in the central Pacific Ocean, a region targeted for seabed mineral exploration for polymetallic nodules. It is a relatively large animal found living inside polymetallic nodules and in xenophyophores (giant Foraminifera) growing on no...
Article
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To protect the range of habitats, species, and ecosystem functions in the Clarion Clipperton Zone (CCZ), a region of interest for deep-sea polymetallic nodule mining in the Pacific, nine Areas of Particular Environmental Interest (APEIs) have been designated by the International Seabed Authority (ISA). The APEIs are remote, rarely visited and poorl...
Article
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Recently, there has been a resurgent interest in the exploration of deep-sea mineral deposits, particularly polymetallic nodules in the Clarion-Clipperton Zone (CCZ), central Pacific. Accurate environmental impact assessment is critical to the effective management of a new industry and depends on a sound understanding of species taxonomy, biogeogra...
Article
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Environmental DNA methods such as metabarcoding have been suggested as possible alternatives or complements to the current practice of morphology-based diversity assessment for characterizing benthic communities in marine sediment. However, the source volume used in sediment eDNA studies is several magnitudes lower than that used in morphological i...
Article
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Metabarcoding of environmental DNA (eDNA) is an attractive complement to morphological methods for surveys and routine monitoring of marine sediment benthic communities. However, metabarcoding and other genetic techniques are heavily affected by choices made during sampling, processing, and analysis. Here, we investigated the effect of different eD...
Chapter
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• The abyss lies between 3 and 6 km water depth and covers more of the Earth’s sur- face than all other habitats combined. • The present chapter is the first in the World Ocean Assessment that is dedicated to the abyss, covering biodiversity, regional dif- ferences, biogeography, and changes and impacts as a result of natural stressors and anthropo...
Article
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Macrofauna are an abundant and diverse component of abyssal benthic communities and are likely to be heavily impacted by polymetallic nodule mining in the Clarion-Clipperton Zone (CCZ). In 2012, the International Seabed Authority (ISA) used available benthic biodiversity data and environmental proxies to establish nine no-mining areas, called Areas...
Conference Paper
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Routine biological monitoring of the areas affected by offshore oil drilling and extraction is critical for ensuring proper environmental management. In addition to sufficient knowledge of the ecosystem affected, formalised e.g. as biotic indices of indicator species, adequate temporal and spatial resolution is also required, to provide accurate in...
Article
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The marine bone biome is a complex assemblage of macro- and microorganisms; however, the enzymatic repertoire to access bone-derived nutrients remains unknown. The bone matrix is a composite material made up mainly of organic collagen and inorganic hydroxyapatite. We conducted field experiments to study microbial assemblages that can use organic bo...
Article
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The Prince Gustav Channel is a narrow seaway located in the western Weddell Sea on the northeastern-most tip of the Antarctic Peninsula. The channel is notable for both its deep (>1200 m) basins, and a dynamic glacial history that most recently includes the break-up of the Prince Gustav Ice Shelf, which covered the southern portion of the channel u...
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Development of benthic components within integrated multi-trophic aquaculture (IMTA) systems warrants more attention, and the development of polychaetes as an extractive component in IMTA systems is ongoing. This study estimates the bioremediation potential of Capitella sp. and Ophryotrocha craigsmithi for coupled and decoupled salmon-driven IMTA....
Article
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Significant effort is spent on monitoring of benthic ecosystems through government funding or indirectly as a cost of business, and metabarcoding of environmental DNA samples has been suggested as a possible complement or alternative to current morphological methods to assess biodiversity. In metabarcoding, a public sequence database is typically u...
Article
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Large parcels of organic matter in the deep sea, such as whale carcasses, harbor a very specialized fauna, most famously the bone-eating worms in the genus Osedax (Annelida, Siboglinidae). Although Osedax was first described only 15 years ago, there are already 26 described species from the Pacific, Atlantic, and Southern Oceans. The high discovery...
Article
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An effective management of vulnerable marine ecosystems is dependent on thorough knowledge of their location. Multibeam bathymetric mapping and targeted remotely operated vehicle (ROV) surveys are currently used to map areas impacted by industrial activities when vulnerable species are expected. However, multibeam bathymetric mapping is not always...
Preprint
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The marine bone biome is a complex assemblage of macro- and microorganisms, however the enzymatic repertoire to access bone-derived nutrients remains unknown. The resilient structure of collagen in bones, its main organic component and its interwoven character with inorganic hydroxyapatite makes it however difficult to be exploited as an organic re...
Article
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Prionospio Malmgren 1867 and Aurospio Maciolek 1981 (Annelida: Spionidae) are polychaete genera commonly found in the deep sea. Both genera belong to the Prionospio complex, whose members are known to have limited distinguishing characters. Morphological identification of specimens from the deep sea is challenging, as fragmentation and other damage...
Article
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We present DNA taxonomy of abyssal polychaete worms from the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruises ‘AB01’ and ‘AB02’ to the UK Seabed Resources Ltd (UKSRL) polymetallic nodule exploration contract area ‘UK-1’, the Ocean Mineral...
Article
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Fish farms are increasingly situated in strong current sites above or near to mixed-bottom habitats that include organisms not normally considered in the context of organic enrichment. This study takes a holistic view of the benthic enrichment process by combining different survey techniques on complimentary spatial scales: conventional macrofaunal...
Article
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Better scientific knowledge of the poorly-known deep sea and areas beyond national jurisdiction (ABNJ) is key to its conservation, an urgent need in light of increasing environmental pressures. Access to marine genetic resources (MGR) for the biodiversity research community is essential to allow these environments to be better characterised. Negoti...
Article
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Capitella sp. and Ophryotrocha craigsmithi received a diet of salmon feces to evaluate their potential to convert fish waste into valuable marine products, e.g. ingredients for fish feed formulation. Production rate and body composition (focusing on fatty acid [FA] profiles) were determined for polychaetes fed fresh, acid-preserved or oven-dried sa...
Article
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The clinging jellyfish Gonionemus sp. is a small hydromedusa species known historically from the Swedish west coast but not reported in recent times. This species is thought to be native to the northwest Pacific where it is notorious for causing severe stings in humans and is considered invasive or cryptogenic elsewhere. This year, unlike in the pa...
Article
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Ensuring that the wealth of resources contained in our oceans are managed and developed in a sustainable manner is a priority for the emerging 'blue economy'. However, modern ecosystem-based management approaches do not translate well to regions where we know almost nothing about the individual species found in the ecosystem. Here, we propose a new...
Article
Sufficient, clean and secure energy is the main driver for a worldwide growing welfare and economic development of a society. Environmental concerns on the expansion of offshore renewable energy and its impact on marine organisms need to be scientifically assessed for risks and consequences. In order to observe the effects of an operating wind farm...
Article
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We present the first DNA taxonomy publication on abyssal Mollusca from the Clarion-Clipperton Zone (CCZ), central Pacific ocean, using material collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise ‘AB01’ to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration area ‘UK-1’ in the eastern CCZ. This is the th...
Article
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The abyssal demosponge Plenaster craigi is endemic to the Clarion - Clipperton Zone (CCZ) in the NE Pacific, a region with abundant seafloor polymetallic nodules and of potential interest for mining. Plenaster craigi encrusts on these nodules and is an abundant component of the ecosystem. To assess the impact of mining operations, it is crucial to...
Article
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The Clarion-Clipperton Zone (CCZ) in the East Pacific is a vast region targeted for deep-sea mineral exploration, for which there are almost no published taxonomic data. Here we describe Plenaster craigi gen. nov. sp. nov. from depths of ∼4000 m in the eastern CCZ polymetallic nodule province. Despite over 40 years of intense exploration in the are...
Article
The immense energy potential of the oceans is being increasingly recognized the world over, at the same time the integrity of marine ecosystems is challenged by pressure from multiple human activities. For good reasons environmental licensing procedures are precautionary and new industries must declare their detrimental impacts and provide mitigati...
Article
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Background Recent years have seen a rapid increase in survey and sampling expeditions to the Clarion-Clipperton Zone (CCZ) abyssal plain, a vast area of the central Pacific that is currently being actively explored for deep-sea minerals (ISA, 2016). Critical to the development of evidence-based environmental policy in the CCZ are data on the bioge...
Article
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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...
Article
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Background We present data from a DNA taxonomy register of the abyssal Cnidaria collected as part of the Abyssal Baseline (ABYSSLINE) environmental survey cruise ?AB01? to the UK Seabed Resources Ltd (UKSRL) polymetallic-nodule exploration area ?UK-1? in the eastern Clarion-Clipperton Zone (CCZ), central Pacific Ocean abyssal plain. This is the sec...