An upper mesopelagic zone carbon budget for the subarctic North Pacific DOI Creative Commons
Brandon M. Stephens, Montserrat Roca‐Martí, Amy E. Maas

et al.

Published: Aug. 20, 2024

Abstract. Mesopelagic zone (MZ) carbon budgets comparing supply with demand can be difficult to constrain due the temporal and spatial offsets between key sources sinks, nuances of measurement techniques used, their associated uncertainties, potential sampling biases. To address some these challenges, EXport Processes in Ocean from RemoTe Sensing (EXPORTS) campaign increased number variety simultaneous measurements monitor variability MZ budget using both a Lagrangian frame reference long-term autonomous collection. In this study, we collate comprehensive combination new previously published organic collected surface (5 m) upper MZ, defined here as depths 100 m 500 m. Research cruise-based were near subarctic North Pacific’s Station Papa (OSP) during August 2018 EXPORTS field campaign. The particulate (POC) into averaged 3.0 mmol C m-2 d-1, roughly equal contributions passively sinking particles deposits active diel vertical migration zooplankton. demand, form respiration, 5.7 most free-living bacterioplankton minor zooplankton particle-attached bacterioplankton. ship-based estimate water column exceeded supply. Moreover, may have been even higher based on trends dissolved oxygen concentration glider biogeochemical float operating November 2018. This imbalance could resolved by particle dynamics influencing timescales utilization prior Net community production (NCP) rates measured preceding spring early summer mooring estimates inorganic concentrations. Seasonal backscattering vicinity OSP, addition decreases carbon, suggest that excess accounted for release, disaggregation, subsequent slow degradation NCP earlier year. OSP presented demonstrates studies attempting fate exported POC require integration samples over short-time (days weeks; ships) long-time (months; remote observations) scales. Finally, mass balance approach, highlight validate dioxide removal through export should consider multiple sample collections monitoring longer time

Language: Английский

Direct observations of microbial community succession on sinking marine particles DOI Creative Commons
Brandon M. Stephens, Colleen A. Durkin, Garrett Sharpe

et al.

The ISME Journal, Journal Year: 2024, Volume and Issue: 18(1)

Published: Jan. 1, 2024

Abstract Microbial community dynamics on sinking particles control the amount of carbon that reaches deep ocean and length time is stored, with potentially profound impacts Earth’s climate. A mechanistic understanding controls particle distributions has been hindered by limited depth- time-resolved sampling methods cannot distinguish individual particles. Here, we analyze microbial communities nearly 400 in conjunction more conventional composite samples to determine how colonization assembly might sequestration ocean. We observed succession corresponding changes metabolic potential larger transporting a significant fraction sea. richness decreased as aged sank; however, increased size attenuation export. This suggests theory island biogeography applies marine Changes POC flux composition depth were reproduced ecosystem model reflected range labilities growth rates. Our results highlight processes particles, isolation which necessary improve models uptake.

Language: Английский

Citations

10
DOM production, removal, and transformation processes in marine systems DOI
Craig A. Carlson, Shuting Liu, Brandon M. Stephens

et al.

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 137 - 246

Published: Jan. 1, 2024

Language: Английский

Citations

4
Oxidation state of bioavailable dissolved organic matter influences bacterioplankton respiration and growth efficiency DOI Creative Commons
Brandon M. Stephens, Paolo Stincone, Daniel Petras

et al.

Communications Biology, Journal Year: 2025, Volume and Issue: 8(1)

Published: Jan. 29, 2025

Oxygen consumption by oceanic microbes can predict respiration (CO2 production) but requires an assumed respiratory quotient (RQ; ΔO2/ΔCO2). Measured apparent RQs (ARQs) be impacted various processes, including nitrification and changes in dissolved organic matter (DOM) composition, leading to discrepancies between ARQ actual RQ. In DOM remineralization experiments conducted the eastern North Atlantic Ocean, ARQs averaged 1.39 ± 0.14, similar predictions for complete of plankton biomass. removed with elevated nominal oxidation state (i.e., more oxidized DOM), as detected liquid chromatography-tandem mass spectrometry, coincided increased hydrolyzable amino acid removal, bacterioplankton (BR), a decreased growth efficiency (BGE). Across experiments, evidence emerged that partial oxidation, driven part members OM43, SAR92 Rhodobacteraceae, elevate BR relative plankton-derived carbon. These rare synoptic measurements interrelated variables reveal complex biochemical cellular processes underlying variability large-scale CO2 production estimates. The is influenced composition metabolic potential bacteria, accounting

Language: Английский

Citations

0
Mix-match synthesis of nanosynbiotics from probiotics and prebiotics to counter gut dysbiosis via AI integrated formulation profiling DOI Creative Commons
Noor Ul Ain, Muhammad Naveed, Tariq Aziz

et al.

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: Aug. 8, 2024

Antibiotics, improper food, and stress have created a dysbiotic state in the gut almost 81% of world's population has been affected due to pandemic COVID-19 prevalence dengue virus past few years. The main intent this study is synthesize nanosynbiotics as nu traceuticals by combining probiotics, prebiotics with nanoformulation. effectiveness was evaluated using variety Nutra-pharmacogenetic assays leading an AI-integrated formulation profiling assessed machine learning methods. Consequently, Acetobacter oryzoeni probiotic inulin prebiotic chosen iron-mediated nanoformulation symbiotic achieved. Nanosynbiotics possessed 89.4, 96.7, 93.57, 83.53, 88.53% potential powers assays. Artificial intelligent solid dispersion high dissolution, absorption, distribution, synergism, addition, they are non-tox, non-allergen docking score - 10.83 kcal/mol, implying best interaction Pregnane X receptor involved dysbiosis. revolutionize treatment strategies through precise targeting modulation microbiome for improved health outcomes disease management promising. Their transformational influence projected be powered integration modern technology customized formulas. Further in-vivo studies required validation nutraceuticals.

Language: Английский

Citations

3
Chemical characterization and cycling of dissolved organic matter DOI
Daniel J. Repeta, Lihini I. Aluwihare

Elsevier eBooks, Journal Year: 2024, Volume and Issue: unknown, P. 13 - 67

Published: Jan. 1, 2024

Language: Английский

Citations

2
Metabolite release by nitrifiers facilitates metabolic interactions in the ocean DOI Creative Commons
Barbara Bayer, Shuting Liu, Katherine B. Louie

et al.

The ISME Journal, Journal Year: 2024, Volume and Issue: 18(1)

Published: Jan. 1, 2024

Language: Английский

Citations

2
Microbial respiration in contrasting ocean provinces via high-frequency optode assays DOI Creative Commons
Melanie R. Cohn, Brandon M. Stephens, Meredith G. Meyer

et al.

Frontiers in Marine Science, Journal Year: 2024, Volume and Issue: 11

Published: June 5, 2024

Microbial respiration is a critical component of the marine carbon cycle, determining proportion fixed that subject to remineralization as opposed being available for export ocean depths. Despite its importance, methodological constraints have led an inadequate understanding this process, especially in low-activity oligotrophic and mesopelagic regions. Here, we quantify rates low 0.2 µ mol O 2 L -1 d contrasting productivity provinces using oxygen optode sensors identify size-fractionated trends. In region North Pacific Ocean at Station Papa, surface whole water microbial was relatively stable 1.2 . Below surface, there decoupling between bacterial production coincided with increased phytodetritus small phytoplankton. Size-fractionated analysis revealed cells <5 m were responsible majority Pacific, both below mixed layer. At Atlantic Porcupine Abyssal Plain, higher (1.7 ) than decreased by 3-fold euphotic zone. The size-fraction contributions total shifted on order days during evolution phytoplankton bloom regular storm disturbances. high-resolution method used captured these significant shifts consistent coinciding stain-based methods historical site estimates. This study highlights dynamic nature across vertical, temporal, factors, emphasizing need sensitive, high-throughput techniques better understand ecosystem metabolism.

Language: Английский

Citations

1
Seasonal and anthropogenic influences on bacterioplankton communities: ecological impacts in the coastal waters of Qinhuangdao, Northern China DOI Creative Commons
Qiuzhen Wang,

Jia Yu,

Xiaofang Li

et al.

Frontiers in Microbiology, Journal Year: 2024, Volume and Issue: 15

Published: June 19, 2024

Marine bacterioplankton play a crucial role in the cycling of carbon, nitrogen, and phosphorus coastal waters. And impact environmental factors on bacterial community structure ecological functions is dynamic ongoing process. To systematically assess relationship between changes communities, this study delved into spatiotemporal distribution predicted metabolic characteristics communities at two estuarine beaches Northern China. Coastal water samples were collected regularly spring, summer, autumn, analyzed combination with parameters community. Results indicated significant seasonal variations as Bacteroidetes Actinobacteria enriched Cyanobacteria proliferated summer. While Pseudomonadota microorganisms associated organic matter decomposition prevailed closely linked to variation temperature, light nutrients such nitrogen phosphorus. Particularly increased tourism activities riverine inputs significantly raised nutrient levels, promoting proliferation specific photosynthetic microorganisms, potentially occurrence phytoplankton blooms. Spearman correlation analysis further revealed correlations salinity, chlorophyll , total dissolved (TDP). Additionally, features spring primarily characterized by enhanced prokaryotic carbon fixation pathways, reflecting rapid adaptation well contributions primary productivity. In involved glycolysis biosynthetic high energy metabolism responses biomass. adapted accelerated conditions through amino acid material pathways. These findings demonstrate that human influence function altering dynamics physical conditions. This provides important scientific insights marine biological under global change.

Language: Английский

Citations

1
Investigating the ocean’s biological pump using thorium-235 and polonium-210 DOI Creative Commons
Samantha J. Clevenger

Published: Feb. 1, 2024

Oceans play a critical role in the Earth’s ability to regulate atmospheric carbon dioxide, absorbing approximately one-third of all anthropogenically-emitted CO2. The biological pump is mechanism which controls oceanic uptake CO2 and sequestration into deeper waters. It complex web processes starting with biota upper ocean transform particulate organic (POC) via photosynthesis, portion ultimately sequestered from atmosphere. Due massive scale these processes, small changes strength can greatly impact levels. Tools used quantify flux biologically relevant elements such as POC biogenic silica are radioisotopes – naturally-occurring clocks allow us look back time study processes. In this thesis, two radioisotope pairs 234Th/238U 210Po/210Pb utilized. Chapter 2 an update measurement method simplifies protocol, allows for expansion use. 3 presents unprecedentedly extensive, non-steady state assess through NASA’s EXPORTS project. involved tracking eddy one month North Atlantic Ocean export over development dual-phase plankton spring bloom. 4, expanded add application tracer farther history export. Extensive comparison systems results new-to-the-field conclusions about concurrent use tracers. This thesis culminates 5, compares three studies community structure data make inferences it relates who present ecosystem. dataset “strong” endmember, WHOI’s Twilight Zone (OTZ) project offers “intermediate” case Northwest Slope, Pacific “weak” endmember. Taken together, expands tracers investigate diverse environments.

Language: Английский

Citations

0
An upper mesopelagic zone carbon budget for the subarctic North Pacific DOI Creative Commons
Brandon M. Stephens, Montserrat Roca‐Martí, Amy E. Maas

et al.

Published: Aug. 20, 2024

Abstract. Mesopelagic zone (MZ) carbon budgets comparing supply with demand can be difficult to constrain due the temporal and spatial offsets between key sources sinks, nuances of measurement techniques used, their associated uncertainties, potential sampling biases. To address some these challenges, EXport Processes in Ocean from RemoTe Sensing (EXPORTS) campaign increased number variety simultaneous measurements monitor variability MZ budget using both a Lagrangian frame reference long-term autonomous collection. In this study, we collate comprehensive combination new previously published organic collected surface (5 m) upper MZ, defined here as depths 100 m 500 m. Research cruise-based were near subarctic North Pacific’s Station Papa (OSP) during August 2018 EXPORTS field campaign. The particulate (POC) into averaged 3.0 mmol C m-2 d-1, roughly equal contributions passively sinking particles deposits active diel vertical migration zooplankton. demand, form respiration, 5.7 most free-living bacterioplankton minor zooplankton particle-attached bacterioplankton. ship-based estimate water column exceeded supply. Moreover, may have been even higher based on trends dissolved oxygen concentration glider biogeochemical float operating November 2018. This imbalance could resolved by particle dynamics influencing timescales utilization prior Net community production (NCP) rates measured preceding spring early summer mooring estimates inorganic concentrations. Seasonal backscattering vicinity OSP, addition decreases carbon, suggest that excess accounted for release, disaggregation, subsequent slow degradation NCP earlier year. OSP presented demonstrates studies attempting fate exported POC require integration samples over short-time (days weeks; ships) long-time (months; remote observations) scales. Finally, mass balance approach, highlight validate dioxide removal through export should consider multiple sample collections monitoring longer time

Language: Английский

Citations

0