Carbonate compensation depth drives abyssal biogeography in the northeast Pacific

Nature Ecology & Evolution, Journal Year: 2023, Volume and Issue: 7(9), P. 1388 - 1397

Published: July 24, 2023

Abstract Abyssal seafloor communities cover more than 60% of Earth’s surface. Despite their great size, abyssal plains extend across modest environmental gradients compared to other marine ecosystems. However, little is known about the patterns and processes regulating biodiversity or potentially delimiting biogeographical boundaries at regional scales in abyss. Improved macroecological understanding remote environments urgent as threats widespread anthropogenic disturbance grow deep ocean. Here, we use a new, basin-scale dataset show existence clear zonation 5,000 km span Clarion–Clipperton Zone (northeast Pacific), an area targeted for deep-sea mining. We found two pronounced biogeographic provinces, shallow-abyssal, separated by transition zone between 4,300 4,800 m depth. Surprisingly, species richness was maintained this boundary phylum-level taxonomic replacements. These transitions are probably related calcium carbonate saturation taxa dependent on structures, such shelled molluscs, appear restricted shallower province. Our results suggest geochemical climatic forcing distributions populations over large spatial provide potential paradigm macroecology, opening new basis regional-scale research conservation strategies largest biome.

Language: Английский

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Microeukaryote metabolism across the western North Atlantic Ocean revealed through autonomous underwater profiling

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Nov. 21, 2023

Abstract Protists (microeukaryotes) are key contributors to marine carbon cycling, influencing the transfer of energy higher trophic levels and vertical movement ocean interior. Their physiology, ecology, interactions with chemical environment still poorly understood in offshore ecosystems, especially deep ocean. Using Autonomous Underwater Vehicle (AUV) Clio , microbial community along a 1,050 km transect western North Atlantic Ocean was surveyed at 10-200 m depth increments capture metabolic microeukaryote signatures spanning gradient oligotrophic, continental margin, productive coastal ecosystems. Plankton biomass collected surface this across features, taxonomy function were examined using paired metatranscriptomic metaproteomic approach. A shift composition observed from euphotic zone through mesopelagic into bathypelagic diverse assemblage consisting haptophytes, stramenopiles, dinoflagellates ciliates represented both transcript protein fractions, foraminifera, radiolaria, picozoa, discoba proteins enriched >200 depth, fungal emerging waters >3,000 depth. In broad community, nitrogen stress biomarkers found sites, phosphorus where Saharan dust input is thought supply iron nitrogen. This multi-omics dataset broadens our understanding how microeukaryotic taxa their functional processes structured environmental gradients temperature, light, macronutrients, trace metals.

Language: Английский

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Assigning the unassigned: A signature-based classification of rDNA metabarcodes reveals new deep-sea diversity

PLoS ONE, Journal Year: 2024, Volume and Issue: 19(2), P. e0298440 - e0298440

Published: Feb. 29, 2024

Environmental DNA metabarcoding reveals a vast genetic diversity of marine eukaryotes. Yet, most the data remain unassigned due to paucity reference databases. This is particularly true for deep-sea meiofauna and eukaryotic microbiota, whose hidden largely unexplored. Here, we tackle this issue by using unique signatures classify unknown metabarcodes assigned foraminifera. We analyzed obtained from 311 sediment samples collected in Clarion-Clipperton Fracture Zone, an area potential polymetallic nodule exploitation Eastern Pacific Ocean. Using designed 37F hypervariable region 18S rRNA gene, were able 802 into 61 novel lineages, which have been placed 27 phylogenetic clades. The comparison new lineages with other foraminiferal datasets shows that are widely distributed deep sea. Five also present shallow-water datasets; however, analysis these separates except one case. While signature-based classification does not solve problem gaps databases, taxonomy-free approach provides insight distribution ecology species represented metabarcodes, could be useful future applications environmental monitoring.

Language: Английский

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Taxonomic and abundance biases affect the record of marine eukaryotic plankton communities in sediment DNA archives

Molecular Ecology Resources, Journal Year: 2024, Volume and Issue: 24(8)

Published: Aug. 26, 2024

Environmental DNA (eDNA) preserved in marine sediments is increasingly being used to study past ecosystems. However, little known about how accurately biodiversity recorded sediment eDNA archives, especially planktonic taxa. Here, we address this question by comparing eukaryotic diversity 273 samples from three water depths and the surface of 24 stations Nordic Seas. Analysis 18S-V9 metabarcoding data reveals distinct assemblages between eDNA. Only 40% Amplicon Sequence Variants (ASVs) detected were also found Remarkably, ASVs shared accounted for 80% total sequence reads suggesting that a large amount plankton transported seafloor, predominantly abundant phytoplankton not all taxa equally archived on seafloor. The deposited was dominated diatoms showed an underrepresentation certain nano- picoplankton (Picozoa or Prymnesiophyceae). Our offers first insights into patterns relation seasonality spatial variability environmental conditions results suggest genetic composition structure community vary considerably throughout column differ what accumulates sediment. Hence, interpretation sedimentary archives should take account potential taxonomic abundance biases when reconstructing changes biodiversity.

Language: Английский

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Pattern changes of microbial communities in urban river affected by anthropogenic activities and their environmental driving mechanisms

Environmental Sciences Europe, Journal Year: 2022, Volume and Issue: 34(1)

Published: Sept. 20, 2022

Abstract The microbial community structure of sediments in the Bahe River Basin, China was studied using a high-throughput sequencing platform and PCR amplification to investigate pattern changes communities urban rivers affected by anthropogenic activities their environmental driving mechanisms. results demonstrated that average total nitrogen phosphorus were 524 734 mg/kg, respectively. T, COD $${\text{NH}}_{4}^{ + }$$ NH 4 + -N water moisture content has significantly impacted on structure. Twenty species with relative abundance > 1% river observed, accounting for 95–99% community. primary Proteobacteria (13.86–69.14%), Firmicutes (1.45–58.33%), Chloroflexi (3.68–26.18%), Actinobacteria (2.7–21.51%), Acidobacteria (0.73–16.36%), Bacteroides (1.53–14.11%), Thermodesulfobacteria (0.1–8.9%), over 90% At class level, γ-proteobacteria, Alphaproteobacteria, Anaerolineae, Bacillus, Bacteroidota, Actinobacteriota, Clostridia, 70% Our provide direct evidence link between environment factors. This demonstrates sediment microorganisms can be applied evaluate pollution levels, which scientific basis control management human activities.

Language: Английский

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