Mixing it up in the ocean carbon cycle and the removal of refractory dissolved organic carbon

Scientific Reports, Год журнала: 2018, Номер 8(1)

Опубликована: Фев. 1, 2018

A large quantity of reduced carbon is sequestered in the ocean as refractory dissolved molecules that persist through several circuits global overturning circulation. Key aspects cycling organic (DOC) remain unknown, making it challenging to predict how this reservoir will respond climate change. Herein we investigate mechanisms remove DOC using bioassay experiments with isolated from surface, mesopelagic and deep waters Atlantic Ocean. The was degradation by native microbial communities, even at elevated concentrations. However, when introduced a series novel environmental conditions, including addition labile substrate, community coastal exposure solar radiation, substantial fraction (7-13%) removed within 1.5 years. Our results suggest while can for millennia, removal rapid they encounter their fate. observed projected climate-induced slowdown circulation could reduce disparate processes. Assuming constant rate production, size increase slows, providing negative feedback rising atmospheric CO2.

Язык: Английский

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Unveiling the enigma of refractory carbon in the ocean

National Science Review, Год журнала: 2018, Номер 5(4), С. 459 - 463

Опубликована: Янв. 30, 2018

Язык: Английский

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Ammonia‐oxidizing archaea release a suite of organic compounds potentially fueling prokaryotic heterotrophy in the ocean

Environmental Microbiology, Год журнала: 2019, Номер 21(11), С. 4062 - 4075

Опубликована: Июль 23, 2019

Summary Ammonia‐oxidizing archaea (AOA) constitute a considerable fraction of microbial biomass in the global ocean, comprising 20%–40% ocean's prokaryotic plankton. However, it remains enigmatic to what extent these chemolithoautotrophic release dissolved organic carbon (DOC). A combination targeted and untargeted metabolomics was used characterize exometabolomes three model AOA strains Nitrosopumilus genus. Our results indicate that marine exude suite compounds with potentially varying reactivities, dominated by nitrogen‐containing compounds. significant released matter (DOM) consists labile compounds, which typically limit heterotrophic activity open ocean waters, including amino acids, thymidine B vitamins. Amino acid rates corresponded ammonia oxidation predominantly hydrophobic as result passive diffusion. Despite low contribution DOC (~0.08%–1.05%) demand, physiologically relevant metabolites could be crucial for microbes are auxotrophic some members globally abundant ubiquitous SAR11 clade.

Язык: Английский

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Functional Molecular Diversity of Marine Dissolved Organic Matter Is Reduced during Degradation

Frontiers in Marine Science, Год журнала: 2017, Номер 4

Опубликована: Июнь 30, 2017

Dissolved organic matter (DOM) is a highly diverse mixture of compounds, accounting for one the world's largest active carbon pools. The surprising recalcitrance some DOM compounds to bacterial degradation has recently been associated with its diversity. However, little known about large-scale patterns marine diversity and change through degradation, in particular considering functional DOM. Here, we analyze development during two data sets comprising very different ages: three-year mesocosm experiment highly-resolved field samples from Atlantic Southern Ocean. molecular composition was determined using ultra-high resolution mass spectrometry. We quantify three conceptually measures, namely richness formulas, abundance-based diversity, Using these measures find stable age >1 year, systematic changes molecules' abundance distribution state, increasing homogeneity respect chemical properties more degraded Coinciding differences sea water density, spatial separated clearly into regions high low joint application yields comprehensive overview on temporal valuable general conclusions drivers consequences

Язык: Английский

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Plastic pollution impacts on marine carbon biogeochemistry

Environmental Pollution, Год журнала: 2020, Номер 268, С. 115598 - 115598

Опубликована: Сен. 10, 2020

Язык: Английский

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