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  1. AU="Jutta Niggemann"
  2. AU="Castilho, Grazielle Rodrigues"
  3. AU="Neza, Brian Nicholas"
  4. AU="van Oppen, Madeleine J H"
  5. AU="Cuevas, J."
  6. AU="Ekendahl, Daniela"
  7. AU="Cantoni, Valeria"
  8. AU="Barrett, Anne E"
  9. AU="van Steijn, Leonie"
  10. AU="Zeng, Zhenling"
  11. AU="Silva Helio B."
  12. AU="Bellicoso, Daniela"
  13. AU="Cruz Viggi, Carolina"

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  1. Artikel ; Online: Dissolved Organic Matter Cycling in the Coastal Upwelling System Off Central Peru During an “El Niño” Year

    Maricarmen Igarza / Thorsten Dittmar / Michelle Graco / Jutta Niggemann

    Frontiers in Marine Science, Vol

    2019  Band 6

    Abstract: The Peruvian upwelling system (PUS) is among the most productive regions in the ocean, with high rates of primary production and an intense oxygen minimum zone (OMZ). The main perturbation of this system is associated to “El Niño” (EN), which affects ... ...

    Abstract The Peruvian upwelling system (PUS) is among the most productive regions in the ocean, with high rates of primary production and an intense oxygen minimum zone (OMZ). The main perturbation of this system is associated to “El Niño” (EN), which affects water mass distribution and reduces primary production. Previous studies in the PUS provided first insights into the dynamics of dissolved organic matter (DOM), but high-resolution studies involving the molecular characterization of the DOM pool to reveal the processes that affect the carbon cycle in this highly productive system are lacking. We characterized the molecular composition of solid-phase extractable DOM (SPE-DOM) in the coastal upwelling system off Central Peru and linked it to specific processes that affect DOM cycling. Seasonal sampling (April, August, and December) was carried out off Central Peru (12°S) during 2015, a low productivity year marked by EN conditions. The DOM molecular composition was obtained via Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). Solid-phase extractable dissolved organic carbon (SPE-DOC) concentrations showed significant differences (p < 0.05) between the water masses present off central Peru. In order to explore if changes in SPE-DOC concentrations were the result of water mass mixing, we applied a conservative mixing (CM) model. The model revealed a non-conservative behavior of SPE-DOC and allowed us to identify two distinct groups of samples with increased and decreased SPE-DOC concentrations, respectively, and one group of samples inside the CM range. Differences in environmental parameters characterizing these groups were in accordance with respective processes associated to production and degradation of SPE-DOC. The trends observed for molecular parameters revealed the imprint of processes related to DOM production and DOM degradation, both biotic (microbial degradation) and abiotic (photodegradation). Our study suggests that even under low productivity conditions like EN, there is an ...
    Schlagwörter Peruvian upwelling system ; Central Peru ; El Niño ; dissolved organic matter ; carbon cycling ; ultrahigh-resolution mass spectrometry ; Science ; Q ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Thema/Rubrik (Code) 550
    Sprache Englisch
    Erscheinungsdatum 2019-05-01T00:00:00Z
    Verlag Frontiers Media S.A.
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  2. Artikel ; Online: Comparison of different solid phase extraction sorbents for the qualitative assessment of dissolved organic nitrogen in freshwater samples using FT-ICR-MS

    Patrick E. Stücheli / Jutta Niggemann / Carsten J. Schubert

    Journal of Limnology, Vol 77, Iss

    2018  Band 3

    Abstract: Fate and reactivity of dissolved organic matter (DOM) is directly linked to its chemical composition. Therefore, molecular characterisation, for example using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), is used for a better ... ...

    Abstract Fate and reactivity of dissolved organic matter (DOM) is directly linked to its chemical composition. Therefore, molecular characterisation, for example using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), is used for a better understanding of those factors. To study organic compounds in the water column, an efficient extraction method is important. The commonly used extraction method for FT-ICR-MS is solid phase extraction (SPE) using a reversed-phase sorbent (BondElut PPL). But this method, to the best of our knowledge, was not evaluated for its ability to extract organic nitrogen compounds which are important building blocks of life and therefore an important fraction of DOM. In this study, several solid phase sorbents were tested for their ability to extract organic nitrogen compounds from water samples of natural aqueous environments. Different cartridges concerning their retention mechanism and pore size were tested. Three cartridges with different extraction mechanism (reversed phase, cation exchange or a mixture of both) or different pore size were tested. Except for one sorbent type, which heavily contaminated the samples with organic molecules, the tested cartridges leached neither a significant amount of dissolved organic carbon (DOC) nor dissolved organic nitrogen (DON). The sorbents were tested with lake water to be able to investigate their functionality in real conditions. It could be shown, that the molecular composition of the sample should be considered for the choice of the sorbent material. Additionally, it was shown that a mixed-bed sorbent is a valuable complementary SPE sorbent for the molecular characterisation of lacustrine samples using FT-ICR-MS and it might also be useful for a quantitative extraction. Furthermore, it could be shown that HyperSep Retain CX sorbent allows to extract a broader range of organic nitrogen compounds leading to a more comprehensive data set for investigating organic nitrogen compounds in lakes using FT-ICR-MS.
    Schlagwörter Solid phase extraction ; organic nitrogen ; limnology ; cation exchange ; Fourier transform ion cyclotron resonance mass spectrometry ; Geography. Anthropology. Recreation ; G ; Physical geography ; GB3-5030 ; Environmental sciences ; GE1-350
    Thema/Rubrik (Code) 540 ; 500
    Sprache Englisch
    Erscheinungsdatum 2018-06-01T00:00:00Z
    Verlag PAGEPress Publications
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  3. Artikel ; Online: The carbon and nitrogen budget of Desmophyllum dianthus—a voracious cold-water coral thriving in an acidified Patagonian fjord

    Sandra R. Maier / Carin Jantzen / Jürgen Laudien / Verena Häussermann / Günter Försterra / Astrid Cornils / Jutta Niggemann / Thorsten Dittmar / Claudio Richter

    PeerJ, Vol 9, p e

    2021  Band 12609

    Abstract: In the North Patagonian fjord region, the cold-water coral (CWC) Desmophyllum dianthus occurs in high densities, in spite of low pH and aragonite saturation. If and how these conditions affect the energy demand of the corals is so far unknown. In a ... ...

    Abstract In the North Patagonian fjord region, the cold-water coral (CWC) Desmophyllum dianthus occurs in high densities, in spite of low pH and aragonite saturation. If and how these conditions affect the energy demand of the corals is so far unknown. In a laboratory experiment, we investigated the carbon and nitrogen (C, N) budget of D. dianthus from Comau Fjord under three feeding scenarios: (1) live fjord zooplankton (100–2,300 µm), (2) live fjord zooplankton plus krill (>7 mm), and (3) four-day food deprivation. In closed incubations, C and N budgets were derived from the difference between C and N uptake during feeding and subsequent C and N loss through respiration, ammonium excretion, release of particulate organic carbon and nitrogen (POC, PON). Additional feeding with krill significantly increased coral respiration (35%), excretion (131%), and POC release (67%) compared to feeding on zooplankton only. Nevertheless, the higher C and N losses were overcompensated by the threefold higher C and N uptake, indicating a high assimilation and growth efficiency for the krill plus zooplankton diet. In contrast, short food deprivation caused a substantial reduction in respiration (59%), excretion (54%), release of POC (73%) and PON (87%) compared to feeding on zooplankton, suggesting a high potential to acclimatize to food scarcity (e.g., in winter). Notwithstanding, unfed corals ‘lost’ 2% of their tissue-C and 1.2% of their tissue-N per day in terms of metabolism and released particulate organic matter (likely mucus). To balance the C (N) losses, each D. dianthus polyp has to consume around 700 (400) zooplankters per day. The capture of a single, large krill individual, however, provides enough C and N to compensate daily C and N losses and grow tissue reserves, suggesting that krill plays an important nutritional role for the fjord corals. Efficient krill and zooplankton capture, as well as dietary and metabolic flexibility, may enable D. dianthus to thrive under adverse environmental conditions in its fjord habitat; ...
    Schlagwörter Scleractinian corals ; Deep-sea corals ; Feeding ; Energy budget ; Zooplankton ; Krill ; Medicine ; R ; Biology (General) ; QH301-705.5
    Thema/Rubrik (Code) 590
    Sprache Englisch
    Erscheinungsdatum 2021-12-01T00:00:00Z
    Verlag PeerJ Inc.
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  4. Artikel ; Online: Environmental drivers of dissolved organic matter molecular composition in the Delaware Estuary

    Helena Osterholz / David L. Kirchman / Jutta Niggemann / Thorsten Dittmar

    Frontiers in Earth Science, Vol

    2016  Band 4

    Abstract: Estuaries as connectors of freshwater and marine aquatic systems are hotspots of biogeochemical element cycling. In one of the best studied temperate estuaries, the Delaware Estuary (USA), we investigated the variability of dissolved organic matter (DOM) ...

    Abstract Estuaries as connectors of freshwater and marine aquatic systems are hotspots of biogeochemical element cycling. In one of the best studied temperate estuaries, the Delaware Estuary (USA), we investigated the variability of dissolved organic matter (DOM) over five sampling cruises along the salinity gradient in August and November of 3 consecutive years. Dissolved organic carbon (DOC) concentrations were more variable in the upper reaches of the estuary (245±49 µmol L-1) than at the mouth of the estuary (129±14 µmol L-1). Bulk DOC decreased conservatively along the transect in November but was non-conservative with increased DOC concentrations mid-estuary in August. Detailed analysis of the solid-phase extractable DOM pool via ultrahigh resolution mass spectrometry (Fourier-transform ion cyclotron resonance mass spectrometry, FT-ICR-MS) revealed compositional differences at the molecular level that were not reflected in changes in concentration. Besides the mixing of terrestrial and marine endmember signatures, river discharge levels and biological activity were found to impact DOM molecular composition. DOM composition changed less between August and November than along the salinity gradient. Relative contributions of presumed photolabile DOM compounds did not reveal non-conservative behavior indicative of photochemical processing; suggesting that on the timescales of estuarine mixing photochemical removal of molecules plays a minor role in the turbid Delaware Bay. Overall, a large portion of molecular formulae overlapped between sampling campaigns and persisted during estuarine passage. Extending the analysis to the structural level via the fragmentation of molecular masses in the FT-ICR-MS cell, we found that the relative abundance of isomers along the salinity gradient did not change, indicating a high structural similarity of aquatic DOM independent of the origin. These results point towards a recalcitrant character of the DOM supplied by the Delaware River. We demonstrate that in addition to bulk DOC ...
    Schlagwörter Dissolved organic matter (DOM) ; Seasonal variation ; Discharges ; Delaware Estuary ; FT-ICR-MS ; Conservative mixing ; Science ; Q
    Thema/Rubrik (Code) 551
    Sprache Englisch
    Erscheinungsdatum 2016-11-01T00:00:00Z
    Verlag Frontiers Media S.A.
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  5. Artikel ; Online: Diatom fucan polysaccharide precipitates carbon during algal blooms

    Silvia Vidal-Melgosa / Andreas Sichert / T. Ben Francis / Daniel Bartosik / Jutta Niggemann / Antje Wichels / William G. T. Willats / Bernhard M. Fuchs / Hanno Teeling / Dörte Becher / Thomas Schweder / Rudolf Amann / Jan-Hendrik Hehemann

    Nature Communications, Vol 12, Iss 1, Pp 1-

    2021  Band 13

    Abstract: The fate of ocean carbon is determined by the balance between primary productivity and heterotrophic breakdown of that photosynthate. Here the authors show that diatoms produce a polysaccharide that resists bacterial degradation, accumulates, aggregates ... ...

    Abstract The fate of ocean carbon is determined by the balance between primary productivity and heterotrophic breakdown of that photosynthate. Here the authors show that diatoms produce a polysaccharide that resists bacterial degradation, accumulates, aggregates and stores carbon during spring blooms.
    Schlagwörter Science ; Q
    Sprache Englisch
    Erscheinungsdatum 2021-02-01T00:00:00Z
    Verlag Nature Portfolio
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  6. Artikel ; Online: Questions remain about the biolability of dissolved black carbon along the combustion continuum

    Sasha Wagner / Alysha I. Coppola / Aron Stubbins / Thorsten Dittmar / Jutta Niggemann / Travis W. Drake / Michael Seidel / Robert G. M. Spencer / Hongyan Bao

    Nature Communications, Vol 12, Iss 1, Pp 1-

    2021  Band 4

    Schlagwörter Science ; Q
    Sprache Englisch
    Erscheinungsdatum 2021-07-01T00:00:00Z
    Verlag Nature Portfolio
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  7. Artikel ; Online: Aerosols as a source of dissolved black carbon to the ocean

    Hongyan Bao / Jutta Niggemann / Li Luo / Thorsten Dittmar / Shuh-Ji Kao

    Nature Communications, Vol 8, Iss 1, Pp 1-

    2017  Band 7

    Abstract: The contribution of atmospheric deposition to the oceanic dissolved black carbon pool (DBC) is unclear. Here, the authors show that water-soluble black carbon is positively correlated with water-soluble organic carbon in marine aerosols, and that ... ...

    Abstract The contribution of atmospheric deposition to the oceanic dissolved black carbon pool (DBC) is unclear. Here, the authors show that water-soluble black carbon is positively correlated with water-soluble organic carbon in marine aerosols, and that atmospheric deposition is a significant source of oceanic DBC.
    Schlagwörter Science ; Q
    Sprache Englisch
    Erscheinungsdatum 2017-09-01T00:00:00Z
    Verlag Nature Portfolio
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  8. Artikel ; Online: Aerosols as a source of dissolved black carbon to the ocean

    Hongyan Bao / Jutta Niggemann / Li Luo / Thorsten Dittmar / Shuh-Ji Kao

    Nature Communications, Vol 8, Iss 1, Pp 1-

    2017  Band 7

    Abstract: The contribution of atmospheric deposition to the oceanic dissolved black carbon pool (DBC) is unclear. Here, the authors show that water-soluble black carbon is positively correlated with water-soluble organic carbon in marine aerosols, and that ... ...

    Abstract The contribution of atmospheric deposition to the oceanic dissolved black carbon pool (DBC) is unclear. Here, the authors show that water-soluble black carbon is positively correlated with water-soluble organic carbon in marine aerosols, and that atmospheric deposition is a significant source of oceanic DBC.
    Schlagwörter Science ; Q
    Sprache Englisch
    Erscheinungsdatum 2017-09-01T00:00:00Z
    Verlag Nature Publishing Group
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  9. Artikel ; Online: Seasonal dynamics of atmospheric and river inputs of black carbon, and impacts on biogeochemical cycles in Halong Bay, Vietnam

    Xavier Mari / Thuoc Chu Van / Benjamin Guinot / Justine Brune / Jean-Pierre Lefebvre / Patrick Raimbault / Thorsten Dittmar / Jutta Niggemann

    Elementa: Science of the Anthropocene, Vol

    2017  Band 5

    Abstract: Emissions of black carbon (BC), a product of incomplete combustion of fossil fuels, biofuels and biomass, are high in the Asia-Pacific region, yet input pathways and rates to the ocean are not well constrained. Atmospheric and riverine inputs of BC in ... ...

    Abstract Emissions of black carbon (BC), a product of incomplete combustion of fossil fuels, biofuels and biomass, are high in the Asia-Pacific region, yet input pathways and rates to the ocean are not well constrained. Atmospheric and riverine inputs of BC in Halong Bay (Vietnam), a hotspot of atmospheric BC, were studied at monthly intervals during one year. Climate in Halong Bay is governed by the monsoon regime, characterized by a northeast winter monsoon (dry season) and southeast summer monsoon (wet season). During the dry season, atmospheric BC concentrations averaged twice those observed during the wet season. In the sea surface microlayer (SML) and underlying water (ULW), concentrations of particulate BC (PBC) averaged 539 and 11 μmol C L–1, respectively. Dissolved BC (DBC) concentrations averaged 2.6 μmol C L–1 in both the SML and ULW. Seasonal variations indicated that PBC concentration in the SML was controlled by atmospheric deposition during the dry season, while riverine inputs controlled both PBC and DBC concentrations in ULW during the wet season. Spatiotemporal variations of PBC and DBC during the wet season suggest that river runoff was efficient in transporting PBC that had accumulated on land during the dry season, and in mobilizing and transporting DBC to the ocean. The annual river flux of PBC was about 3.8 times higher than that of DBC. The monsoon regime controls BC input to Halong Bay by favoring dry deposition of BC originating from the north during the dry season, and wet deposition and river runoff during the wet season. High PBC concentrations seem to enhance the transfer of organic carbon from dissolved to particulate phase by adsorbing dissolved organic carbon and stimulating aggregation. Such processes may impact the availability and biogeochemical cycling of other dissolved substances, including nutrients, for the coastal marine ecosystem.
    Schlagwörter Black carbon ; Atmospheric deposition ; River input ; Sea surface microlayer ; Dissolved organic carbon ; Particulate organic carbon ; Environmental sciences ; GE1-350
    Sprache Englisch
    Erscheinungsdatum 2017-12-01T00:00:00Z
    Verlag BioOne
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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  10. Artikel ; Online: Biogeochemical Impacts of a Black Carbon Wet Deposition Event in Halong Bay, Vietnam

    Xavier Mari / Benjamin Guinot / Chu Van Thuoc / Justine Brune / Jean-Pierre Lefebvre / Pradeep Ram Angia Sriram / Patrick Raimbault / Thorsten Dittmar / Jutta Niggemann

    Frontiers in Marine Science, Vol

    2019  Band 6

    Abstract: Black carbon (BC) is emitted to the atmosphere during biomass, biofuel, and fossil fuel combustion, and leaves the atmosphere via dry or wet deposition on land and on the ocean. On a global scale, wet deposition accounts for about 80% of the total ... ...

    Abstract Black carbon (BC) is emitted to the atmosphere during biomass, biofuel, and fossil fuel combustion, and leaves the atmosphere via dry or wet deposition on land and on the ocean. On a global scale, wet deposition accounts for about 80% of the total atmospheric BC inputs to the ocean. The input of BC particles to the ocean can enrich surface waters with carbon and associated elements, and owing to high porosity and surface-active properties, BC can alter biogeochemical cycles by sorbing dissolved compounds and promoting aggregation. The rain-mediated input of BC to the ocean and its consequences on nutrient concentrations and particle dynamics were studied in Halong Bay, Vietnam, during a 24-h cycle impacted by short and heavy rainfall events. This study suggests that once introduced in the surface ocean via wet deposition, BC sorbs dissolved organic matter (DOM) and stimulates aggregation processes. The observed wet deposition events were characterized by sudden and pulsed inputs of BC particles that created a thin layer of sinking surface-active aggregates, acting as a net-like scavenger for DOM, nutrients (especially phosphate), and small particles. In addition, the wet deposition events coincided with an enrichment of nutrients in the surface microlayer, with an excess input of nitrogen relative to phosphorus leading to an increase of the molar N:P ratio from 24:1 to 37:1. In the underlying water, the molar N:P ratio also increased (i.e., from 39:1 to 64:1), and this can be attributed to the preferential scavenging of dissolved P-compounds on sinking BC-aggregates.
    Schlagwörter black carbon ; wet deposition ; sorption ; aggregation ; DOM ; nutrients ; Science ; Q ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Thema/Rubrik (Code) 551
    Sprache Englisch
    Erscheinungsdatum 2019-04-01T00:00:00Z
    Verlag Frontiers Media S.A.
    Dokumenttyp Artikel ; Online
    Datenquelle BASE - Bielefeld Academic Search Engine (Lebenswissenschaftliche Auswahl)

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