Deep-Sea Research Part I-Oceanographic Research Papers最新文献

{"title":"Interaction between the M2 internal tides and typhoon-induced near-inertial waves near the Luzon Strait","authors":"Anzhou Cao ,&nbsp;Zheng Guo ,&nbsp;Xu Chen ,&nbsp;Xinyu Guo ,&nbsp;Jinbao Song","doi":"10.1016/j.dsr.2025.104452","DOIUrl":"10.1016/j.dsr.2025.104452","url":null,"abstract":"<div><div>The South China Sea is abundant with intense internal tides (ITs) and typhoon-induced near-inertial waves (NIWs), which inevitably interact with each other. Based on the numerical simulation results, the interaction between the M₂ ITs and typhoon Megi-induced NIWs in the deep ocean near the Luzon Strait is studied. The interaction gives rise to sum- and difference-frequency waves, denoted as the <em>f</em>M₂ and M₂-<em>f</em> waves. Results of this study highlight the contribution of the M₂-<em>f</em> waves to shear enhancement: The kinetic energy of the M₂-<em>f</em> waves is one order of magnitude smaller than that of the M₂ ITs, but the domain-averaged vertical shear squared caused by the M₂-<em>f</em> waves is comparable to that of the M₂ ITs. The IT-NIW interaction is dominated by the product of vertical internal tidal velocity and vertical shear of horizontal near-inertial velocity, which is followed by the product of horizontal near-inertial velocity and horizontal shear of horizontal internal tidal velocity. The IT-NIW interaction influences the evolution of near-inertial kinetic energy through modulating the energy exchange and near-inertial energy flux, which are site-dependent. In the modulation of energy exchange, the terms associated with horizontal shear of horizontal internal tidal velocity play crucial roles. Whereas in the modulation of near-inertial energy flux, the terms associated with vertical shear of horizontal near-inertial velocity are dominant.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"217 ","pages":"Article 104452"},"PeriodicalIF":2.3,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133978","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rock bottom: Colonization patterns of deep-sea Arctic and subarctic dropstones (200–1300 m)","authors":"Sophie Wolvin ,&nbsp;Jean-François Hamel ,&nbsp;Annie Mercier","doi":"10.1016/j.dsr.2025.104454","DOIUrl":"10.1016/j.dsr.2025.104454","url":null,"abstract":"<div><div>Hard substrata of allochthonous origin, such as ice-rafted dropstones, can provide essential habitat for benthic communities in the polar and subpolar deep sea, acting as “islands” in otherwise finer-grained sedimentary environments. The present study explored the diversity and distribution patterns of morphospecies (msp/mspp) present on dropstones collected at depths of ∼200–500 m in the Labrador Sea (LAB) and ∼700–1300 m in Baffin Bay (BAF), respectively spanning subarctic and Arctic regions of eastern Canada. Specifically, the zonation, intra- and interspecific interactions, and succession of all colonizers were examined. Based on <em>in</em>-<em>situ</em> images, dropstones exhibited ∼94% greater epibenthic megafaunal richness than similar surfaces of the substratum immediately surrounding them. Analysis of three dropstones collected from each of six sites documented a total of 101 sessile and motile taxa spanning 10 phyla. Across sites, bryozoans dominated at all depths and locations (27 mspp, plus 3 dead) followed by poriferans (27 mspp), 19 cnidarians, eight arthropods, eight annelids, five chordates (tunicates), three echinoderms, three molluscs, and one foraminifer. There were 19 mspp that spanned both LAB and BAF, with greater overall richness in the subarctic region (62 vs 26 mspp). A total of 64 sessile mspp occurred above the stone-sediment interface (e.g., cnidarians and poriferans), whereas 22 mspp (mostly bryozoans) occurred at the stone-sediment interface; one morphospecies of polychaete occurred below. The most abundant morphospecies was an arborescent bryozoan, while two encrusting bryozoans covered the most surface area. Eight morphospecies occurred as just one individual or colony per stone, and 35 mspp appeared to maintain an exclusion zone between conspecifics (e.g., tube-dwelling annelids, hydrozoans, and anthozoans). Conversely, in 51 mspp conspecifics occurred abutting one another (e.g., bryozoans and poriferans). Allospecific exclusion zones appeared to occur in 27 mspp (e.g., bryozoans and annelids), whereas 59 allospecifics (e.g., poriferans, cnidarians, and chordates) occurred within touching distance. Secondary colonization (including cases of epibiosis) was observed in 83 mspp, documenting 204 unique pairings of hosts and colonizers. The number and diversity of morphospecies colonizing dropstones in the deep sea of the eastern Canadian Arctic and subarctic support the role of dropstones as oases that facilitate connectivity in an otherwise poorly diversified epibenthic environment.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"217 ","pages":"Article 104454"},"PeriodicalIF":2.3,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133520","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Strong magnetism and geochemical characteristics of sediment in Challenger Deep and their indications for sources","authors":"KaiWei Wang ,&nbsp;YongHong Wang ,&nbsp;QiuYu Yue ,&nbsp;XiaoHua Zhang ,&nbsp;JiWen Liu ,&nbsp;Chunhui Xiao ,&nbsp;Toshiya Kanamatsu ,&nbsp;Michael Strasser ,&nbsp;Rui Bao","doi":"10.1016/j.dsr.2025.104455","DOIUrl":"10.1016/j.dsr.2025.104455","url":null,"abstract":"<div><div>Understanding the properties of trench sediments is an important aspect of comprehending the sources and transport variations of trench sediments. This study seeks to identify the sources of sediment and understand the mechanisms driving sediment source variation in the Challenger Deep, based on the environmental magnetic characteristics and geochemical properties of the MT20-750 core retrieved from a depth of 10,815 m in the Mariana Trench. The proximal sediment source of the MT20-750 core comprises mainly altered bedrock components from the southern Pacific Plate and volcanic eruption materials from the northern Philippine Plate, while the distal source is primarily aeolian dust input, with biogenic materials also contributing. The overall magnetic susceptibility values of the sediments in the Challenger Deep are significantly higher, reaching 3–5 times that of other regions in the Pacific Ocean. The strong magnetic properties of these sediments are primarily due to the enhanced alteration of the southern subducting plate rocks, which are mainly composed of basalt rich in iron and magnesium (mafic basalt), under the action of Pacific bottom water. This represents a normal state when sediments are funneled into the trench axis and preserved in an oxidizing environment. However, the sediments from the northern Philippine Sea Plate, mainly composed of tuffaceous rocks with lower Fe, Mg, and Ti content, intermittently enter the trench during seismic events or turbidity flows. These events alter the sediment composition in the trench, leading to a decrease in magnetic susceptibility values, with the change in provenance primarily driven by the varying intensity of geological processes and the specific conditions of sediment transport.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"217 ","pages":"Article 104455"},"PeriodicalIF":2.3,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133521","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vertical variations in zooplankton size spectra down to 3,000 m depth and significant effects of the sizes of Calanoida and Ergasilida across the subarctic, transitional, and subtropical regions of the western North Pacific","authors":"Dongwoo Kim ,&nbsp;Sota Komeda ,&nbsp;Kohei Matsuno ,&nbsp;Atsushi Yamaguchi","doi":"10.1016/j.dsr.2025.104445","DOIUrl":"10.1016/j.dsr.2025.104445","url":null,"abstract":"<div><div>Zooplankton size spectra are crucial for evaluating marine ecosystem structure, with copepods being the predominant taxa within the marine zooplankton communities. Among copepods, Calanoida and Ergasilida are the two numerically dominant taxa. Despite their importance, limited information exists regarding the effects of these two taxa on the overall zooplankton size spectra. This study aimed to comprehensively evaluate the regional and vertical changes in zooplankton size spectra, normalised biomass size spectrum (NBSS), and size diversity across subarctic, transitional, and subtropical regions of the western North Pacific Ocean. Additionally, the study aimed to investigate the effects of size variations in two dominant copepod taxa, Calanoida and Ergasilida, on the overall zooplankton size spectra. To achieve this, vertically stratified zooplankton samples were collected from 12 layers, ranging from the sea surface to a depth of 3000 m, at five stations across the subtropical to subarctic western North Pacific. The samples were analysed using ZooScan to assess the overall zooplankton size spectra and the effects of Calanoida and Ergasilida on it. Across all stations, the NBSS slopes became moderate, and the size diversity increased with increasing depth, particularly evident for the oxygen minimum layer (OML) at approximately 1000 m depth. These patterns reflect a high proportion of large-sized zooplankton in the deeper layers and a lower predation pressure from micronektonic fish around the OML. Calanoida and Ergasilida accounted for 43.3% and 24.6% of the mean zooplankton abundance, respectively. Among the two taxa, Calanoida exhibited significant changes in body size depending on the station and depth, being larger in the subarctic region and deeper layers. Ergasilida showed minimal changes in body size relative to location and depth. The body size of Calanoida significantly influenced the overall zooplankton size spectra. Therefore, the dominance of large-sized Calanoida induced a moderate NBSS slope and high size diversity in the overall zooplankton size spectra. The results of this study indicate that the size of Calanoida, the dominant taxon in the zooplankton community, primarily governs the size spectra of the overall zooplankton community.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"217 ","pages":"Article 104445"},"PeriodicalIF":2.3,"publicationDate":"2025-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Interannual variability in surface mesozooplankton in the Western Antarctic Peninsula during two anomalous years","authors":"Camila Máximo Leonor ,&nbsp;Erik Muxagata","doi":"10.1016/j.dsr.2025.104444","DOIUrl":"10.1016/j.dsr.2025.104444","url":null,"abstract":"<div><div>Zooplankton play a key role in the Southern Ocean, are closely linked to oceanographic variations and are highly sensitive to environmental changes. The Western Antarctic Peninsula (WAP) is a critical global climate hotspot where the variability and vulnerability of marine ecosystems are particularly evident. This study aims to characterize the variability of surface mesozooplankton across the Gerlache (GS) and Bransfield (BS) straits. Data were collected with a continuous plankton recorder (CPR) during the austral summer of 2016 (CPR-34 route) and 2017 (CPP-35 route), enabling extensive spatial mapping of zooplankton communities. In 2016, the average sea surface temperature (SST) was 0.57 °C, whereas in 2017, it increased to a maximum of 2.13 °C. The surface salinity (SS) was lower in 2017 (average 33.86). High chlorophyll-<em>a</em> values were recorded in the GS in 2016 (43.78 mg m⁻³). PERMANOVA revealed significant differences in community composition between the year and location site. Beta diversity analysis revealed nestedness in 2016, with Copepoda dominating the mesozooplankton community, particularly <em>Metridia gerlachei</em> and <em>Metridia longa,</em> which accounted for 85% of the total abundance of Copepoda. In 2017, events of replacement, known as turnover, were observed, with a shift from copepods to salps along with lower local diversity. The BS had a relatively high abundance in both years, reflecting the sampling periods and dial migration patterns. CCA revealed positive correlations between salps and temperature and negative correlations between salinity and copepods. These findings highlight distinct community structure patterns driven by specific environmental conditions linked to major climatic events, i.e., the ENSO and SAM, offering insights into zooplankton responses to anomalous oceanographic conditions in the WAP.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"217 ","pages":"Article 104444"},"PeriodicalIF":2.3,"publicationDate":"2025-01-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133980","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Short-period cross-strait internal waves from wave-topography-hydrodynamics interactions: Observations and 3-D model results in the strait of Gibraltar","authors":"Carlos J. González ,&nbsp;Juan J. Gomiz-Pascual ,&nbsp;Jesús Gómez-Enri ,&nbsp;Alfredo Izquierdo ,&nbsp;Miguel Bruno ,&nbsp;Rafael Mañanes ,&nbsp;Óscar Álvarez","doi":"10.1016/j.dsr.2025.104443","DOIUrl":"10.1016/j.dsr.2025.104443","url":null,"abstract":"<div><div>The origin, characteristics, and behavior of cross-strait short-period internal waves in the Strait of Gibraltar are analyzed, by means of a 3D, baroclinic, non-hydrostatic, hydrodynamic model, as well as satellite SAR images. The origin of these cross-strait waves was found to be related to the reflection of the main longitudinal (along-strait) internal wave on the continental shelf slope, where the reflected wave is firstly arrested by the eastward tidal current, and then released towards the northern coast once this tidal current has weakened enough to achieve its subcritical value. The main example of this topographic wave interaction is the cross-strait internal wave reflected from the African shore east of Tangier Bay, which propagates north-westwards towards the Iberian coast near Tarifa. Other waves along the Strait are also found. The latter explains the presence of internal waves in unexpected directions of propagation at times far later than the main longitudinal wave at certain locations, all of them with plausible influence on mixing processes, upwelling phenomena and biogeochemical activity in the area.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"217 ","pages":"Article 104443"},"PeriodicalIF":2.3,"publicationDate":"2025-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143133977","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sedimentary, geochemical and reservoir characteristics of the Quaternary submarine fan in the Qiongdongnan basin","authors":"Junfeng Zhang ,&nbsp;Detian Yan ,&nbsp;Jianxiang Pei ,&nbsp;Wei Luo ,&nbsp;Entao Liu ,&nbsp;Peng Song ,&nbsp;Tong Li ,&nbsp;Zeyu Lu ,&nbsp;Xudong Lin","doi":"10.1016/j.dsr.2024.104429","DOIUrl":"10.1016/j.dsr.2024.104429","url":null,"abstract":"<div><div>The South China Sea holds significant marine oil and gas resources, with the Qiongdongnan Basin being a key area. Submarine fans, as major marine reservoir systems, are crucial for storing natural gas and gas hydrates. However, research on the large Quaternary submarine fan in this basin is limited. Our study examines the importance of Quaternary submarine fans in the Qiongdongnan Basin, South China Sea, with a focus on their development. By utilizing 3D seismic data and core samples, our research aims to analyze submarine fan features and their developmental processes. The submarine fans are divided into four units, with Unit 1–2 submarine fans and internal waterways gradually increasing in size, and Unit 2 to Unit 4 submarine fans and waterway development decreasing in size. Through major and trace element analysis of core samples, we discovered that each major and trace element has different characteristics in different units, such as higher relative contents of Zr and Ti in Units 3 and 4, and higher relative contents of K in Unit 2. Simultaneously microscopic observations and reservoir characteristic parameters are utilized to evaluate the quality of submarine fan reservoirs. We reveal that Unit 2 has the best reservoir quality, followed by Unit 1, and that Units 3 and 4 have poor reservoirs quality This research enhances understanding of the sedimentary evolution of submarine fans in the Qiongdongnan Basin, offers insights into regional geological processes and contributes to global deep-water basin exploration and management.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"215 ","pages":"Article 104429"},"PeriodicalIF":2.3,"publicationDate":"2025-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143138710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New insights on the deep alkaline phosphatase paradox from a site in the Northeastern Pacific Ocean","authors":"Kerry Dykens ,&nbsp;Robert Letscher ,&nbsp;Atsushi Matsuoka ,&nbsp;Kai Ziervogel","doi":"10.1016/j.dsr.2024.104419","DOIUrl":"10.1016/j.dsr.2024.104419","url":null,"abstract":"<div><div>Extracellular hydrolytic enzymes are the main tools for microorganisms to access and degrade organic matter in the ocean. We investigated potential activities of four hydrolytic enzymes (alkaline phosphatase, beta-glucosidase, leucine aminopeptidase, chitinase) in the water column and surficial sediments at a deepwater site in the Northeastern Pacific Ocean (water depth: 2658 m). Our goal was to investigate the potential role of (re-)suspended particles as a source for enzyme activities in subsurface waters. Alkaline phosphatase (AP) dominated hydrolytic activities in subsurface waters and in sediments, reaching up to two orders of magnitude higher rates compared with the other three enzymes. Peak AP activities in the center of the oxygen minimum zone and in bottom waters were decoupled from concentrations of inorganic phosphorous (P_i), a pattern known as the <em>deep AP paradox</em>. A weak correlation between AP and bacterial abundances indicated that a fraction of AP was physically detached from their source cells (i.e., cell-free enzymes) and associated with particles either from surface waters (marine snow) or resuspended from the seafloor. We estimated that cell-free AP activities, which are decoupled from nutritional needs and oxidative processes of their source cells, contribute about 2%–9% of regenerated P_i in the bathypelagic Northeastern Pacific Ocean. (Re-)suspended particles as a source of cell-free AP thus play an important yet understudied role in deep-ocean elemental cycles.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"215 ","pages":"Article 104419"},"PeriodicalIF":2.3,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vertical zonation and environmental drivers of North-West Pacific abyssal and hadal mobile faunal communities","authors":"Denise J.B. Swanborn ,&nbsp;Todd Bond ,&nbsp;Jessica L. Kolbusz ,&nbsp;Megan E. Cundy ,&nbsp;Melanie S. Stott ,&nbsp;Elin A. Thomas ,&nbsp;Hiroshi Kitazato ,&nbsp;Alan J. Jamieson","doi":"10.1016/j.dsr.2024.104418","DOIUrl":"10.1016/j.dsr.2024.104418","url":null,"abstract":"<div><div>This study examines the composition, vertical zonation and drivers of mobile abyssal and hadal faunal assemblages to understand the environmental patterns underlying biological organisation at lower abyssal and hadal depths. Biological data were analysed from 96 baited lander deployments across five North-West Pacific subduction trenches and one triple trench junction (the Mariana Trench, Philippine Trench, Ryukyu Trench, Japan Trench, Izu-Ogasawara Trench and Boso Triple Junction) and combined with environmental metrics of terrain geomorphology and oceanography at deployment locations. Hierarchical clustering revealed three depth-driven faunal zones, representing an abyssal-hadal transition community (∼5500–6500 m), an upper hadal community (∼7000–7500 m) and a lower hadal community (&gt;8500 m). Clustering results support an abyssal-hadal ecotone &gt;6500 m depth and a further hadal transition ∼8000 m. Environmental factors explained 40.4% of community structure, with depth and location as main contributors to the final model. These factors, through the latter's relationships with surface oceanography and productivity, were also key determinants of relative abundance, diversity, richness and the total relative abundance of dominant faunal groups and families among deployments. Results suggest limited ecological effects of intra-trench environmental variability, and highlight a need for further high-resolution studies sampling a range of environmental conditions and their associated biodiversity within individual hadal features.</div></div>","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"215 ","pages":"Article 104418"},"PeriodicalIF":2.3,"publicationDate":"2024-11-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142697153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutrient fluxes, oxygen consumption and fatty acid composition from deep-water demo- and hexactinellid sponges from New Zealand","authors":"Tanja Stratmann ,&nbsp;Kathrin Busch ,&nbsp;Anna de Kluijver ,&nbsp;Michelle Kelly ,&nbsp;Sadie Mills ,&nbsp;Sven Rossel ,&nbsp;Peter J. Schupp","doi":"10.1016/j.dsr.2024.104416","DOIUrl":"10.1016/j.dsr.2024.104416","url":null,"abstract":"&lt;div&gt;&lt;div&gt;Sponges are an important component of deep-water ecosystems enhancing eukaryotic biodiversity by hosting diverse endo- and epibiota and providing three dimensional habitats for benthic invertebrates and fishes. As holobionts they are important hosts of microorganisms which are involved in carbon and nitrogen cycling. While increasing exploration of deep-water habitats results in new sponge species being discovered, little is known about their physiology and role in nutrient fluxes. Around New Zealand (Southwest Pacific), the sponge biodiversity is particularly high, and we selected six deep-sea sponge genera (&lt;em&gt;Saccocalyx&lt;/em&gt;, &lt;em&gt;Suberites&lt;/em&gt;, &lt;em&gt;Tedania&lt;/em&gt;, &lt;em&gt;Halichondria&lt;/em&gt;/&lt;em&gt;Dendoricella&lt;/em&gt;, &lt;em&gt;Lissodendoryx&lt;/em&gt;) and a member of the Sceptrulophora order for &lt;em&gt;in-situ&lt;/em&gt; and &lt;em&gt;ex-situ&lt;/em&gt; experiments.&lt;/div&gt;&lt;div&gt;We investigated the biochemical composition of the sponges, measured oxygen consumption and inorganic nutrient fluxes, as well as bacterial and phospholipid-derived fatty acid (PLFA) compositions. Our aim was to assess differences in fluxes and fatty acid composition among sponges and linking their bacterial communities to nitrogen cycling processes.&lt;/div&gt;&lt;div&gt;All sponges excreted nitrite and ammonia. Nitrate and phosphate excretion were independent of phylum affiliation (Demospongiae, Hexactinellida). Nitrate was excreted by &lt;em&gt;Halichondria&lt;/em&gt;/&lt;em&gt;Dendoricella&lt;/em&gt; and &lt;em&gt;Lissodendoryx&lt;/em&gt;, whereas &lt;em&gt;Suberites&lt;/em&gt;, &lt;em&gt;Tedania&lt;/em&gt;, and Sceptrulophora consumed it. Phosphate was excreted by Sceptrulophora and &lt;em&gt;Halichondria&lt;/em&gt;/&lt;em&gt;Dendoricella&lt;/em&gt; and consumed by all other sponges. Oxygen consumption rates ranged from 0.17 to 3.56 ± 0.60 mmol O&lt;sub&gt;2&lt;/sub&gt; g C&lt;sup&gt;-1&lt;/sup&gt; d&lt;sup&gt;−1&lt;/sup&gt;.&lt;/div&gt;&lt;div&gt;The PLFA composition was very sponge-genera dependent and consisted mostly of long-chain fatty acids. Most PLFAs were sponge-specific, followed by bacteria-specific PLFAs, and others.&lt;/div&gt;&lt;div&gt;All sponges, except for &lt;em&gt;Suberites&lt;/em&gt;, were low-microbial abundance (LMA) sponges whose bacterial community composition was dominated by Proteobacteria, Bacteroidota, Planctomycetota, and Nitrospinota. &lt;em&gt;Suberites&lt;/em&gt; consisted of high-microbial abundance (HMA) sponges with Proteobacteria, Chloroflexota, Acidobacteriota, and Actinobacteriota as dominant bacteria.&lt;/div&gt;&lt;div&gt;Based on the inorganic nitrogen flux measurements, we identified three types of nitrogen cycling in the sponges: In type 1, sponges (&lt;em&gt;Dendoricella&lt;/em&gt; spp. indet., &lt;em&gt;Lissodendoryx&lt;/em&gt;) respired aerobically and ammonificated organic matter (OM) to ammonium, fixed N&lt;sub&gt;2&lt;/sub&gt; to ammonium, and nitrified aerobically heterotrophically produced ammonium to nitrate and nitrite. In type 2, sponges (&lt;em&gt;Halichondria&lt;/em&gt; sp., Sceptrulophora, &lt;em&gt;Suberites&lt;/em&gt;, &lt;em&gt;Tedania&lt;/em&gt;) respired OM aerobically and ammonificated it to ammonium. They also reduced nitrate anaerobically to ammonium via dissimilatory nitrate reduction to amm","PeriodicalId":51009,"journal":{"name":"Deep-Sea Research Part I-Oceanographic Research Papers","volume":"214 ","pages":"Article 104416"},"PeriodicalIF":2.3,"publicationDate":"2024-11-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142658364","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}