Comparison of Two 16S rRNA Primers (V3–V4 and V4–V5) for Studies of Arctic Microbial Communities

Frontiers in Microbiology, Journal Year: 2021, Volume and Issue: 12

Published: Feb. 16, 2021

Microbial communities of the Arctic Ocean are poorly characterized in comparison to other aquatic environments as their horizontal, vertical, and temporal turnover. Yet, recent studies showed that marine ecosystem harbors unique microbial community members adapted harsh environmental conditions, such near-freezing temperatures extreme seasonality. The gene for small ribosomal subunit (16S rRNA) is commonly used study taxonomic composition natural environment. Several primer sets this marker have been extensively tested across various sample sets, but these typically originated from low-latitude environments. An explicit evaluation primer-set performances representing currently lacking. To select a suitable set studying microbiomes habitats (sea ice, surface water, snow, deep ocean basin, deep-sea sediment), we conducted performance between two widely targeting different hypervariable regions 16S rRNA (V3-V4 V4-V5). We observed both were highly similar total down genus rank, which was also confirmed independently by subgroup-specific catalyzed reporter deposition-fluorescence

Language: Английский

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Sea-ice derived meltwater stratification slows the biological carbon pump: results from continuous observations

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: Dec. 15, 2021

The ocean moderates the world's climate through absorption of heat and carbon, but how much carbon will continue to absorb remains unknown. North Atlantic Ocean west (Baffin Bay/Labrador Sea) east (Fram Strait/Greenland Greenland features most intense anthropogenic globally; biological pump (BCP) contributes substantially. As Arctic sea-ice melts, BCP changes, impacting global other critical attributes (e.g. biodiversity). Full understanding requires year-round observations across a range ice conditions. Here we present such observations: autonomously collected Eulerian continuous 24-month time-series in Fram Strait. We show that, compared ice-unaffected conditions, derived meltwater stratification slows by 4 months, shift from an export retention system, with measurable impacts on benthic communities. This has implications for ecosystem dynamics future warmer where seasonal zone is expected expand.

Language: Английский

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Carbon Export in the Ocean: A Biologist's Perspective

Annual Review of Marine Science, Journal Year: 2022, Volume and Issue: 15(1), P. 357 - 381

Published: Sept. 3, 2022

Understanding the nature of organic matter flux in ocean remains a major goal oceanography because it impacts some most important processes ocean. Sinking particles are for carbon dioxide removal from atmosphere and its movement to deep They also feed life below ocean's productive surface sustain sea, addition depositing on seafloor. However, magnitude all these is dependent transformation sinking during their journey through water column. This review focuses sea via biological pump examines that prevent this downward movement-namely, attenuation microbial colonization zooplankton feeding. It discusses how depth-specific interactions among microbes, zooplankton, aggregates determine export as well nutrient recycling, which turn impact production Earth's climate.

Language: Английский

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The polar night shift: seasonal dynamics and drivers of Arctic Ocean microbiomes revealed by autonomous sampling

ISME Communications, Journal Year: 2021, Volume and Issue: 1(1)

Published: Dec. 1, 2021

The Arctic Ocean features extreme seasonal differences in daylight, temperature, ice cover, and mixed layer depth. However, the diversity ecology of microbes across these contrasting environmental conditions remain enigmatic. Here, using autonomous samplers sensors deployed at two mooring sites, we portray an annual cycle microbial diversity, nutrient concentrations physical oceanography major hydrographic regimes Fram Strait. ice-free West Spitsbergen Current displayed a marked separation into productive summer (dominated by diatoms carbohydrate-degrading bacteria) regenerative winter state heterotrophic Syndiniales, radiolarians, chemoautotrophic bacteria, archaea). autumn post-bloom with maximal depletion featured Coscinodiscophyceae, Rhodobacteraceae (e.g. Amylibacter) SAR116 clade. Winter replenishment nitrate, silicate phosphate, linked to vertical mixing unique microbiome that included Magnetospiraceae Dadabacteriales, fueled following phytoplankton bloom. spring-summer succession Phaeocystis, Grammonema Thalassiosira coincided ephemeral peaks Aurantivirga, Formosa, Polaribacter NS lineages, indicating metabolic relationships. In East Greenland Current, deeper sampling depth, cover polar water masses concurred weaker seasonality stronger signature. ice-related comprised Bacillaria, Naviculales, Polarella, Chrysophyceae Flavobacterium ASVs. Low advection Atlantic Water diminished abundances bacteria while others such as Phaeocystis increased, suggesting Atlantification alters structure eventually biological carbon pump. These insights promote understanding night Ocean, region severely affected climate change.

Language: Английский

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Atlantic water influx and sea-ice cover drive taxonomic and functional shifts in Arctic marine bacterial communities

The ISME Journal, Journal Year: 2023, Volume and Issue: 17(10), P. 1612 - 1625

Published: July 8, 2023

The Arctic Ocean is experiencing unprecedented changes because of climate warming, necessitating detailed analyses on the ecology and dynamics biological communities to understand current future ecosystem shifts. Here, we generated a four-year, high-resolution amplicon dataset along with one annual cycle PacBio HiFi read metagenomes from East Greenland Current (EGC), combined this datasets spanning different spatiotemporal scales (Tara MOSAiC) assess impact Atlantic water influx sea-ice cover bacterial in Ocean. Densely ice-covered polar waters harboured temporally stable, resident microbiome. reduced resulted dominance seasonally fluctuating populations, resembling process "replacement" through advection, mixing environmental sorting. We identified signature populations distinct regimes, including night high-ice cover, assessed their ecological roles. Dynamics were consistent across wider Arctic; e.g. those associated dense ice winter EGC abundant central winter. Population- community-level revealed metabolic distinctions between bacteria affiliated conditions; former increased potential use bacterial- terrestrial-derived substrates or inorganic compounds. Our evidence over provides novel insights into indicates progressing Biological Atlantification warming Ocean, consequences for food webs biogeochemical cycles.

Language: Английский

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Sea-ice melt determines seasonal phytoplankton dynamics and delimits the habitat of temperate Atlantic taxa as the Arctic Ocean atlantifies

ISME Communications, Journal Year: 2024, Volume and Issue: 4(1)

Published: Jan. 1, 2024

The Arctic Ocean is one of the regions where anthropogenic environmental change progressing most rapidly and drastically. impact rising temperatures decreasing sea ice on marine microbial communities yet not well understood. Microbes form basis food webs in Ocean, providing energy for larger organisms. Previous studies have shown that Atlantic taxa associated with low light are robust to more polar conditions. We compared which extent melt influences light-associated phytoplankton dynamics biodiversity over two years at mooring locations Fram Strait. One deployed pure water, second intermittently ice-covered Marginal Ice Zone. Time-series analysis amplicon sequence variants abundance a 2-year period, allowed us identify co-occurring exhibit similar patterns throughout annual cycle. then examined how alterations conditions affect prevalence species. During high periods diatoms, populations dominated, while temperate were weakly represented. Furthermore, we found pelagic ice-associated taxa, such as

Language: Английский

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Carbon dioxide sink in the Arctic Ocean from cross-shelf transport of dense Barents Sea water

Nature Geoscience, Journal Year: 2022, Volume and Issue: 16(1), P. 82 - 88

Published: Nov. 21, 2022

Abstract Large amounts of atmospheric carbon can be exported and retained in the deep sea on millennial time scales, buffering global warming. However, while Barents Sea is one most biologically productive areas Arctic Ocean, retention times were thought to short. Here we present observations, complemented by numerical model simulations, that revealed a widespread lateral injection approximately 2.33 kt C d −1 from shelf some 1,200 m Nansen Basin, driven Bottom Water transport. With increasing distance outflow region, plume expanded penetrated into even deeper waters sediment. The seasonally fluctuating but continuous increases sequestration 1/3 feeds community Basin. Our findings combined with those other regions carbon-rich polar dense highlight importance as sink. Resolving uncertainties around negative feedbacks warming due ice decline will necessitate observation changes bottom water formation biological productivity at resolution high enough quantify future injection.

Language: Английский

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Seasonal patterns of vertical flux in the northwestern Barents Sea under Atlantic Water influence and sea-ice decline

Progress In Oceanography, Journal Year: 2023, Volume and Issue: 219, P. 103132 - 103132

Published: Sept. 27, 2023

The northern Barents Sea is a productive Arctic inflow shelf with seasonal ice cover and as such, location an efficient downward export of particulate organic matter through the biological carbon pump.The region under strong influence Atlantification sea-ice decline, resulting in longer open water summer period. In order to understand how these processes pump, it important identify spatial dynamics vertical flux matter. 2019 2021, short-term sediment traps were deployed between 30 200m depth along latitudinal transect northwestern during March, May, August, December. Vertical carbon, δ13C δ15N values, Chl-a, protists fecal pellets assessed. We identified clear pattern, highest May August (178 ± 202 159 79 mg C m-2 d‾1, respectively). Fluxes December March < 45 d‾1. was characterized by diatom- Chl a-rich fluxes high variability, while had higher contribution small flagellates, spatially more homogenous. Standing stocks suspended suggesting retention system late summer. gradient Atlantic Water probably led variability spring, due their on primary productivity. conclude that efficiency pump prolonged open-water period depends reworking small, slow sinking material into efficiently or aggregates, occurrence mixing.

Language: Английский

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Reduced efficiency of pelagic–benthic coupling in the Arctic deep sea during lower ice cover

Scientific Reports, Journal Year: 2023, Volume and Issue: 13(1)

Published: April 25, 2023

Abstract Pelagic–benthic coupling describes the connection between surface-water production and seafloor habitats via energy, nutrient mass exchange. Massive ice loss warming in poorly studied Arctic Chukchi Borderland are hypothesized to affect this coupling. The strength of pelagic–benthic was compared 2 years varying climate settings, 2005 2016, based on δ 13 C 15 N stable isotopes food-web end-members pelagic deep-sea benthic consumers. Considerably higher isotopic niche overlap generally shorter distance were found food web components than suggesting weaker latter, low-ice year. values indicated more refractory consumed by benthos 2016 fresher reaching 2005. Higher zooplankton indirectly suggested a contribution algae 2016. difference these is consistent with energy retention within system, perhaps due strong stratification Amerasian Basin recent decade. Weaker can be expected continue study area, reducing biomass remineralization capacity; monitoring area needed confirm prediction.

Language: Английский

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Unveiling pelagic-benthic coupling associated with the biological carbon pump in the Fram Strait (Arctic Ocean)

Nature Communications, Journal Year: 2025, Volume and Issue: 16(1)

Published: Jan. 20, 2025

Language: Английский

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