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View article: Using stable isotopes to describe the trophic structure of gelatinous zooplankton across the deep pelagic
Using stable isotopes to describe the trophic structure of gelatinous zooplankton across the deep pelagic Open
Although gelatinous zooplankton are key members of marine ecosystems and food webs, their trophic ecology is poorly described across the deep pelagic. We used stable carbon (bulk tissue) and nitrogen (bulk tissue and amino acid) isotope an…
View article: Carbohydrate content controls vertical variations in carbon to nitrogen ratios of organic particles within the euphotic zone in the northwest Sargasso Sea
Carbohydrate content controls vertical variations in carbon to nitrogen ratios of organic particles within the euphotic zone in the northwest Sargasso Sea Open
Latitudinal variations in the carbon:nitrogen (C:N) ratio of particulate organic matter are well-established, but vertical (depth) variations within the euphotic zone remain largely unexplored. Here, we found that C:N ratios (mol:mol) of t…
View article: A reproductive and trophic analysis of corals in a degraded environment
A reproductive and trophic analysis of corals in a degraded environment Open
View article: Transformations of Particulate Organic Matter from the Surface to the Abyssal Plain in the North Pacific as Inferred from Compound-Specific Stable Isotope and Microbial Community Analyses
Transformations of Particulate Organic Matter from the Surface to the Abyssal Plain in the North Pacific as Inferred from Compound-Specific Stable Isotope and Microbial Community Analyses Open
View article: Design, development, and implementation of IsoBank: A centralized repository for isotopic data
Design, development, and implementation of IsoBank: A centralized repository for isotopic data Open
Stable isotope data have made pivotal contributions to nearly every discipline of the physical and natural sciences. As the generation and application of stable isotope data continues to grow exponentially, so does the need for a unifying …
View article: Particulate mercury export in the Central Pacific Ocean using 234Th238U disequilibria
Particulate mercury export in the Central Pacific Ocean using 234Th238U disequilibria Open
Mercury (Hg) is a potent neurotoxin that enters the food web and may contaminate commercial, recreational, subsistence, and ceremonial fish stocks. Understanding the pathways by which this contamination occurs in marine systems is thus an …
View article: Vertical trophic structure and niche partitioning of gelatinous predators in a pelagic food web: Insights from stable isotopes of siphonophores
Vertical trophic structure and niche partitioning of gelatinous predators in a pelagic food web: Insights from stable isotopes of siphonophores Open
Gelatinous zooplankton are increasingly recognized as key components of pelagic ecosystems, and there have been many recent insights into their ecology and roles in food webs. To examine the trophic ecology of siphonophores (Cnidaria, Hydr…
View article: Variable carbon isotope fractionation of photosynthetic communities over depth in an open-ocean euphotic zone
Variable carbon isotope fractionation of photosynthetic communities over depth in an open-ocean euphotic zone Open
Marine particulate organic carbon (POC) contributes to carbon export, food webs, and sediments, but uncertainties remain in its origins. Globally, variations in stable carbon isotope ratios (δ 13 C values) of POC between the upper and lowe…
View article: Marine particle size-fractionation indicates organic matter is processed by differing microbial communities on depth-specific particles
Marine particle size-fractionation indicates organic matter is processed by differing microbial communities on depth-specific particles Open
Passive sinking flux of particulate organic matter in the ocean plays a central role in the biological carbon pump and carbon export to the ocean’s interior. Particle-associated microbes colonize particulate organic matter, producing “hots…
View article: Small particles and heterotrophic protists support the mesopelagic zooplankton food web in the subarctic northeast Pacific Ocean
Small particles and heterotrophic protists support the mesopelagic zooplankton food web in the subarctic northeast Pacific Ocean Open
A quantitative understanding of the mesopelagic zooplankton food web is key to development of accurate carbon budgets and geochemical models in marine systems. Here we use compound specific nitrogen stable isotope analysis of amino acids t…
View article: Deconvolving mechanisms of particle flux attenuation using nitrogen isotope analyses of amino acids
Deconvolving mechanisms of particle flux attenuation using nitrogen isotope analyses of amino acids Open
Particulate organic matter settling out of the euphotic zone is a major sink for atmospheric carbon dioxide and serves as a primary food source to mesopelagic food webs. Degradation of this organic matter encompasses a suite of mechanisms …
View article: Compound specific isotope and enantiomer analyses to better understand the impacts of marine microbes on oceanic carbon export
Compound specific isotope and enantiomer analyses to better understand the impacts of marine microbes on oceanic carbon export Open
View article: Reconciliation of total particulate organic carbon and nitrogen measurements determined using contrasting methods in the North Pacific Ocean as part of the NASA EXPORTS field campaign
Reconciliation of total particulate organic carbon and nitrogen measurements determined using contrasting methods in the North Pacific Ocean as part of the NASA EXPORTS field campaign Open
Measurements of particulate organic carbon (POC) are critical for understanding the ocean carbon cycle, including biogenic particle formation and removal processes, and for constraining models of carbon cycling at local, regional, and glob…
View article: Mercury isotopic evidence for the importance of particles as a source of mercury to marine organisms
Mercury isotopic evidence for the importance of particles as a source of mercury to marine organisms Open
The origin of methylmercury in pelagic fish remains unclear, with many unanswered questions regarding the production and degradation of this neurotoxin in the water column. We used mercury (Hg) stable isotope ratios of marine particles and…
View article: Distinguishing zooplankton fecal pellets as a component of the biological pump using compound‐specific isotope analysis of amino acids
Distinguishing zooplankton fecal pellets as a component of the biological pump using compound‐specific isotope analysis of amino acids Open
Zooplankton contribute a major component of the vertical flux of particulate organic matter to the ocean interior by packaging consumed food and waste into large, dense fecal pellets that sink quickly. Existing methods for quantifying the …
View article: Carbon isotope ratios of particulate organic carbon in the lower euphotic zone
Carbon isotope ratios of particulate organic carbon in the lower euphotic zone Open
Latitudinal variations in sea surface δ 13 C values of particulate organic carbon (δ 13 C POC ) are now well recognized, but no largescale efforts have been made to describe variations in δ 13 C POC over depth in the water column.We recent…
View article: An operational overview of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) Northeast Pacific field deployment
An operational overview of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) Northeast Pacific field deployment Open
The goal of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) field campaign is to develop a predictive understanding of the export, fate, and carbon cycle impacts of global ocean net primary production. To accomplish this go…
View article: Open-Ocean Minima in δ13C Values of Particulate Organic Carbon in the Lower Euphotic Zone
Open-Ocean Minima in δ13C Values of Particulate Organic Carbon in the Lower Euphotic Zone Open
Extensive studies in the 1980s–1990s led to the characterization of latitudinal variations in sea surface δ13C values of particulate organic carbon (δ13CPOC), and relationships were found with CO2 concentrations, temperature, growth rates,…
View article: Particulate Organic Carbon Deconstructed: Molecular and Chemical Composition of Particulate Organic Carbon in the Ocean
Particulate Organic Carbon Deconstructed: Molecular and Chemical Composition of Particulate Organic Carbon in the Ocean Open
The dynamics of the particulate organic carbon (POC) pool in the ocean are central to the marine carbon cycle. POC is the link between surface primary production, the deep ocean, and sediments. The rate at which POC is degraded in the dark…
View article: Deep zooplankton rely on small particles when particle fluxes are low
Deep zooplankton rely on small particles when particle fluxes are low Open
The fate of organic matter (OM) in the deep ocean remains enigmatic, with little understood regarding the flux and its utilization by deep food webs. We used compound‐specific nitrogen stable isotope ratios of source amino acids measured i…
View article: Molecular indicators of methane metabolisms at cold seeps along the United States Atlantic Margin
Molecular indicators of methane metabolisms at cold seeps along the United States Atlantic Margin Open
Anaerobic oxidation of methane (AOM) and the environmental conditions supporting AOM on continental margins is an essential component to global methane budgets. Diagnostic lipid biomarkers and their compound specific isotope analysis prese…
View article: Size fractionated zooplankton C:N, d13C, and d15N from the EXPORTS cruise on R/V Roger Revelle (RR1813) during August and September 2018
Size fractionated zooplankton C:N, d13C, and d15N from the EXPORTS cruise on R/V Roger Revelle (RR1813) during August and September 2018 Open
Size fractionated zooplankton C:N
View article: Mercury Cycling in the North Pacific Subtropical Gyre as Revealed by Mercury Stable Isotope Ratios
Mercury Cycling in the North Pacific Subtropical Gyre as Revealed by Mercury Stable Isotope Ratios Open
The oceans are an important global reservoir for mercury (Hg), and marine fish consumption is the dominant human exposure pathway for its toxic methylated form. A more thorough understanding of the global biogeochemical cycle of Hg require…
View article: Stable carbon isotope ratios of archaeal glycerol dibiphytanyl glycerol tetraether (GDGT) lipids from KN210-04 Cruise in spring 2013
Stable carbon isotope ratios of archaeal glycerol dibiphytanyl glycerol tetraether (GDGT) lipids from KN210-04 Cruise in spring 2013 Open
Stable carbon isotope ratios of archaeal glycerol dibiphytanyl glycerol tetraether (GDGT) lipids have been proposed as a proxy to infer past changes in the carbon isotope composition (δ13C) of dissolved inorganic carbon (DIC). The premise …
View article: Compound-Specific Isotope Geochemistry in the Ocean
Compound-Specific Isotope Geochemistry in the Ocean Open
Compound-specific isotope analysis encompasses a variety of methods for examining the naturally occurring isotope ratios of individual organic molecules. In marine environments, these methods have revealed heterogeneous sources and alterat…
View article: Glycerol dialkyl glycerol tetraethers (GDGT) abundance in suspended particulate matter from the South-west and Equatorial Atlantic Ocean
Glycerol dialkyl glycerol tetraethers (GDGT) abundance in suspended particulate matter from the South-west and Equatorial Atlantic Ocean Open
The TEX86 paleotemperature proxy is based on the distribution of archaeal glycerol dibiphytanyl glycerol tetraether (GDGT) lipids preserved in marine sediments, yet both the influence of different physiological factors on the structural di…
View article: Stable isotope analysis of micronekton around Hawaii reveals suspended particles are an important nutritional source in the lower mesopelagic and upper bathypelagic zones
Stable isotope analysis of micronekton around Hawaii reveals suspended particles are an important nutritional source in the lower mesopelagic and upper bathypelagic zones Open
Several studies have found that the respiratory demand for carbon by the mesopelagic community exceeds carbon supply through the particulate sinking flux by up to two to three orders of magnitude, suggesting that mesopelagic communities re…
View article: Diet of the prehistoric population of Rapa Nui (Easter Island, Chile) shows environmental adaptation and resilience
Diet of the prehistoric population of Rapa Nui (Easter Island, Chile) shows environmental adaptation and resilience Open
Objectives The Rapa Nui “ecocide” narrative questions whether the prehistoric population caused an avoidable ecological disaster through rapid deforestation and over‐exploitation of natural resources. The objective of this study was to cha…
View article: Geoscience 2020: Cyberinfrastructure to reveal the past, comprehend the present,and envision the future
Geoscience 2020: Cyberinfrastructure to reveal the past, comprehend the present,and envision the future Open