Photochemical formation of water-soluble oxyPAHs, naphthenic acids, and other hydrocarbon oxidation products from Cook Inlet, Alaska crude oil and diesel in simulated seawater spills

Environmental Science Advances, Journal Year: 2023, Volume and Issue: 2(3), P. 447 - 461

Published: Jan. 1, 2023

Hydrocarbon oxidation products (HOPs) formed from crude oil and diesel were generated laboratory simulated spills at four different periods (1, 4, 7, 10 days) under environmental conditions that mimicked those in Cook Inlet, Alaska.

Language: Английский

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Hydrological Controls on Dissolved Organic Matter Composition throughout the Aquatic Continuum of the Watershed of Selin Co, the Largest Lake on the Tibetan Plateau

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(11), P. 4668 - 4678

Published: March 9, 2023

Alpine river and lake systems on the Tibetan Plateau are highly sensitive indicators amplifiers of global climate change important components carbon cycle. Dissolved organic matter (DOM) encompasses in aquatic systems, yet knowledge about DOM variation throughout river–lake continuum within alpine regions is limited. We used optical spectroscopy, ultrahigh-resolution mass spectrometry (Fourier transform ion cyclotron resonance spectrometry), stable water isotopic measurements to evaluate linkages between composition hydrological connection. investigated glacial influences watershed Selin Co, including upstream glacier-fed rivers downstream-linked lakes. found that dissolved concentration increased, whereas specific ultraviolet absorbance (SUVA254) decreased along continuum. Relative rivers, downstream lakes had low relative abundances polyphenolic condensed aromatic compounds humic-like substances but increased aliphatics protein-like compounds. SUVA254 while with enriched isotope δ2H-H2O, indicating aromaticity declined autochthonous production flow paths. Glacier meltwater contributed elevated aliphatic headwater streams, aromatics were than conclude changes conditions, glacier melt driven by a warming climate, will significantly alter potentially their biogeochemical function surface waters Plateau.

Language: Английский

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Identification of next-generation International Humic Substances Society reference materials for advancing the understanding of the role of natural organic matter in the Anthropocene

Aquatic Sciences, Journal Year: 2023, Volume and Issue: 85(1)

Published: Jan. 1, 2023

Abstract Many challenges remain before we can fully understand the multifaceted role that natural organic matter (NOM) plays in soil and aquatic systems. These despite considerable progress has been made understanding NOM’s properties reactivity using latest analytical techniques. For nearly 4 decades, International Humic Substances Society (IHSS, which is a non-profit scientific society) distributed standard substances adhere to strict isolation protocols reference materials are collected bulk originate from clearly defined sites. NOM samples offer relatively uniform for designing experiments developing new methods. The isolating NOM, humic fulvic acid fractions of utilize well-established preparative scale column chromatography reverse osmosis used by international community study across range disciplines engineered systems, thereby seeding transfer knowledge research fields. Recently, powerful techniques characterize have revealed complexities its composition transcend “microbial” vs. “terrestrial” precursor paradigm. To continue advance Anthropocene epoch, workshop was convened identify potential sites would encompass sources be relevant studying mediating environmental biogeochemical processes. We anticipate expanding portfolio IHSS available will enable this diverse group scientists engineers better globally under influence anthropogenic mediated changes.

Language: Английский

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Unraveling the Linkages between Molecular Abundance and Stable Carbon Isotope Ratio in Dissolved Organic Matter Using Machine Learning

Environmental Science & Technology, Journal Year: 2023, Volume and Issue: 57(46), P. 17900 - 17909

Published: April 20, 2023

Dissolved organic matter (DOM) is a complex mixture of molecules that constitutes one the largest reservoirs on Earth. While stable carbon isotope values (δ13C) provide valuable insights into DOM transformations from land to ocean, it remains unclear how individual respond changes in properties such as δ13C. To address this, we employed Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) characterize molecular composition 510 samples China Coastal Environments, with 320 having δ13C measurements. Utilizing machine learning model based 5199 formulas, predicted mean absolute error (MAE) 0.30‰ training data set, surpassing traditional linear regression methods (MAE 0.85‰). Our findings suggest degradation processes, microbial activities, and primary production regulate rivers ocean continuum. Additionally, accurately without known other published sets, reflecting trend along This study demonstrates potential capture relationships between bulk parameters, particularly larger sets increasing research future.

Language: Английский

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Using Community Science to Reveal the Global Chemogeography of River Metabolomes

Metabolites, Journal Year: 2020, Volume and Issue: 10(12), P. 518 - 518

Published: Dec. 20, 2020

River corridor metabolomes reflect organic matter (OM) processing that drives aquatic biogeochemical cycles. Recent work highlights the power of ultrahigh-resolution mass spectrometry for understanding metabolome composition and river metabolism. However, there have been no studies on global chemogeography surface water sediment using techniques. Here, we describe a community science effort from Worldwide Hydrobiogeochemistry Observation Network Dynamic Systems (WHONDRS) consortium to characterize in span multiple stream orders biomes. We distribution key aspects including elemental groups, chemical classes, indices, inferred biochemical transformations. show significantly differ across are more rich variable. also use transformations identify core metabolic processes shared among sediment. Finally, observe significant spatial variation metabolites between rivers eastern western portions contiguous United States. Our not only provides basis patterns cycles but demonstrates endeavors can enable research projects unfeasible with traditional models.

Language: Английский

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