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  • 2010-2014  (11)
  • 2005-2009  (1)
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  • 1
    In: Biogeosciences, Göttingen : Copernicus Publ., 2004, 9(2012), 11, Seite 4629-4643, 1726-4170
    In: volume:9
    In: year:2012
    In: number:11
    In: pages:4629-4643
    Materialart: Artikel
    ISSN: 1726-4170
    Sprache: Englisch
    Anmerkung: Auch als elektronisches Dokument verfügbar: http://www.biogeosciences.net/9/4629/2012/bg-9-4629-2012.pdf
    Standort Signatur Einschränkungen Verfügbarkeit
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  • 2
    Online-Ressource
    Online-Ressource
    Dordrecht :Springer Netherlands,
    Schlagwort(e): Coastal zone management. ; Electronic books.
    Beschreibung / Inhaltsverzeichnis: Coastal areas face rising pressures from land use change, developmental activities, shoreline erosion, biodiversity losses and natural calamities. This volume addresses those issues in light of sustainability, focusing on the most urgent current problems.
    Materialart: Online-Ressource
    Seiten: 1 online resource (289 pages)
    Ausgabe: 1st ed.
    ISBN: 9789048130689
    DDC: 333.917
    Sprache: Englisch
    Anmerkung: Intro -- Title Page -- Copyright Page -- Foreword -- Preface -- About the Editors -- Table of Contents -- SECTION 1 Evaluation, Status Prediction, Modelling and Developments of Coastal Zones: Management Issues -- 1 Observational Needs for Sustainable Coastal Prediction and Management -- 1. INTRODUCTION -- 1.1 Defining the Earth System -- 1.2 What is Sustainability? -- 1.3 Modelling the Earth System -- 1.4 Earth System Prediction -- 1.5 Observing the Earth System for Sustainable Management -- 2. OBSERVATIONS FOR SUSTAINABLE COASTAL MANAGEMENT -- 2.1 Observing the Natural-human System -- 2.2 Observing the Coast from Microbes to Man -- 2.3 A Prototype Regional Earth System Prediction for an Estuary -- 2.4 Model-data Synthesis for Sustainable Management -- 3. CONCLUDING THOUGHTS -- REFERENCES -- 2 Ecological Modelling as a Tool for Coastal Ecosystem Management -- 1. INTRODUCTION -- 2. COASTAL ECOSYSTEM MANAGEMENT AND MODELLING -- 3. STATISTICAL ECOSYSTEM MODELLING -- 4. DYNAMIC ECOSYSTEM MODELLING -- 4.1 Hydrodynamic Modelling -- 4.1.1 Hydrostatic Models -- 4.1.2 Non-hydrostatic Models -- 4.1.3 Challenges of Current Hydrodynamic/Physical Models -- 4.2 Lower Trophic Level Modelling -- 4.3 Higher Trophic Level Food Web Modelling -- 4.4 Sediment Flux Modelling -- 5. SPECIAL ISSUES -- 5.1 Marshes, Wetlands and Mangroves -- 5.2 Data Assimilation -- 5.3 Submerged Aquatic Vegetation Modelling -- 5.4 Model Skill Assessment -- 6. CONCLUSION AND FUTURE DIRECTIONS -- REFERENCES -- 3 Current Status of Coastal Zone Management Practices in India -- 1. INTRODUCTION -- 2. STATUS OF INDIAN COASTAL ENVIRONMENT -- 3. IMPACT OF SEA LEVEL RISE ON THE INDIAN COASTAL ENVIRONMENT -- 4. MAJOR INITIATIVES FOR PROTECTION OF MARINE AND COASTAL ENVIRONMENT IN INDIA -- 4.1 Implementation of the CRZ Notification -- 4.2 Current Status of the CRZ. , 4.3 Objections against the CZM Notification -- 4.3.1 The CZM Notification - Conservation -- 4.3.2 The CZM Notification - Sustainable Development -- 4.3.3 The CZM Notification - Livelihoods -- 5. CONCLUSION -- REFERENCES -- 4 Climate Resilient Coastal Zone Development in Bangladesh: Participatory Governance for Common Resources Management -- 1. INTRODUCTION -- 2. COMMON PROPERTY REGIME: AN ENTRY POINT FOR POVERTY REDUCTION -- 2.1 Participatory Governance of the Common Resources -- 2.2 Case Studies on Individual, Community and Systematic Capability Approach -- 2.3 Discussion on Case Studies and Way Forward -- 3. COASTAL FOREST RESOURCES MANAGEMENT THROUGH SCIENTIFIC APPROACH -- 4. COASTAL LAND RESOURCES MANAGEMENT THROUGH PARTICIPATORY APPROACH -- 5. CREATE MECHANISMS TO ENSURE STAKEHOLDERS' PARTICIPATION IN BIODIVERSITY CONSERVATION AT LOCAL LEVEL -- 6. ESTABLISHMENT OF COMMON WEALTH AND PARTICIPATORY MANAGEMENT -- 6.1 Common Wealth for Sustainable Management (CWSM) - With Special Reference to SPA -- 6.2 CWSM - With Special Reference to Shrimp Cultivation -- 6.3 CWSM - With Special Reference to Coastal Embankments and Its Erosion Control -- 6.4 CWSM - With Special Reference to Joint Coastal Forest Management -- 7. CONCLUSIONS -- REFERENCES -- 5 Present Status, Challenges and Management of the Japanese Coastal Zone Environment -- 1. INTRODUCTION -- 2. FACTS ABOUT THE JAPANESE COASTLINE -- 3. MAJOR CONCERNS OF JAPANESE COAST -- 3.1 Sea Level Rise and Climate Change -- 3.2 Eco-hydrological Conditions -- 3.3 Anthropogenic Utilization and Their Impact -- 3.4 Disaster Situation and Their Prevention -- 4. COASTAL ZONE MANAGEMENT IN JAPAN -- 4.1 Legal Framework of Coastal Management -- 4.2 Integrated Coastal Zone Management-Concept -- 4.3 ICZM Practices in Japan -- 4.4 Challenges for Integrated Coastal Zone Management -- 5. CONCLUSIONS -- REFERENCES. , 6 Integrating Hydrologic and Hydrodynamic Models for Decision Support Systems and Management of Coastal Zones and Estuaries -- 1. INTRODUCTION -- 2. STUDY AREA -- 3. MATERIALS AND METHODS -- 3.1 Mixing/flow Dynamics -- 3.2 Spatially Distributed Hydrologic Forcing -- 3.3 Calibration, Validation/Verification with a Case Study -- 4. RESULTS AND DISCUSSIONS -- 5. CONCLUSIONS -- REFERENCES -- 7 Creation of System "Delta-Sea" as a Basis of Ecosystem Approach to the Management of Large Aral Sea's Coastal Zone -- 1. INTRODUCTION -- 2. SOUTHERN PREARALIE: DEVELOPING SITUATION -- 2.1 Basic Results of Researches Carried Out and Suggestions for Aral Sea's Survival -- 2.2 Eternal Russian Question: What to do? -- 3. CONCLUSION -- REFERENCES -- SECTION 2 Coastal Zone Water Resources (Quantity and Quality): Challenges for Sustainability -- 8 Critical Evaluation of the Recent Development and Trends in Submarine Groundwater Discharge Research in Asia -- 1. INTRODUCTION -- 2. PHENOMENOLOGICAL DESCRIPTION AND DRIVERS -- 3. ESTIMATION OF THE MAGNITUDE OF SGD -- 3.1 Investigations from the Land Side -- 3.2 Investigations from the Sea Side -- 3.3 Indirect Indicators of SGD -- 3.4 Mixing Near the Sea Shore -- 4. IMPORTANCE OF SGD IN ASIAN OUTLOOK -- 5. CURRENT STATUS OF SGD RESEARCH IN ASIA -- 5.1 Japan -- 5.2 Korea -- 5.3 India -- 5.4 Bangladesh -- 5.5 Thailand -- 5.6 China -- 6. FUTURE PERSPECTIVES -- 7. SUMMARY -- REFERENCES -- 9 Influence of Climate Factors on the Groundwater Resources of Coastal Tamilnadu -- 1. INTRODUCTION -- 1.1 Study Area -- 1.2 Quaternary Formations -- 1.3 Depth to Water Table -- 2. METHODOLOGY -- 3. HYDROGEOCHEMISTRY -- 3.1 Tritium -- 3.2 Geochemical Nature -- 3.3 18O -- 3.4 13C -- 4. CONCLUSION -- REFERENCES -- 10 Natural Arsenic in Coastal Groundwaters in the Bengal Delta Region in West Bengal, India -- 1. INTRODUCTION. , 2. MATERIALS AND METHODS -- 2.1 Study Area -- 2.2 Sampling and Analytical Techniques -- 3. RESULTS AND DISCUSSION -- 3.1 pH, Redox and Major Ion Characteristics -- 3.2 Distribution of Arsenic, Iron, Manganese and DOC -- 3.3 Relationship between the Key Water Quality Parameters with Redox Sensitive Elements -- 3.4 Statistical Evaluation of the Data -- 3.4.1 Factor 1 -- 3.4.2 Factor 2 -- 3.4.3 Factor 3 -- 4. CONCLUSIONS -- REFERENCES -- 11 Chemical Composition and Origin of the Coastal Zone Thermal Springs in Far East Russia -- 1. INTRODUCTION -- 2. MATERIALS AND METHODS -- 3. STUDY AREA -- 4. RESULTS AND DISCUSSION -- 4.1 Major Ions -- 4.2 Trace Elements -- 4.2.1 Siderophile Elements -- 4.2.2 Chalcophile Elements -- 4.2.3 Lithophile Group -- 4.2.4 Rare-earth Elements (REE) -- 4.3 Gas Composition -- 4.4 Origin of Thermal Waters -- 5. CONCLUSIONS -- REFERENCES -- SECTION 3 Biodiversity of Coastal Zones and Its Sustainability -- 12 Organic Matter and Mangrove Productivity -- 1. INTRODUCTION -- 2. ORGANIC MATTER SOURCES AND SINKS -- 3. CHEMICAL CHARACTERISTICS OF ORGANIC MATTER -- 3.1 Atomic C:N Ratio and Stable Carbon Isotopes -- 3.2 Molecular Biomarkers -- 4. OUTWELLING AND TRANSPORT OF MANGROVE ORGANIC MATTER -- 5. SUMMARY AND CONCLUSION -- REFERENCES -- 13 Influence of Terrestrial Inputs on Mangrove and Coral Reef: Primary Productivity of the Andaman Islands -- 1. BACKGROUND -- 2. STUDY AREA -- Mangrove Forests of the Andaman Islands -- Coral Reef Ecosystems of the Andaman Islands -- Significance of the Terrestrial and Coastal Ecosystems -- Mineralization and Immobilization -- 3. MATERIALS AND METHODS -- Sampling of Surface Water -- Sediment Denitrification -- Primary Productivity -- Leaf Litter C:N Estimation -- 4. RESULTS AND DISCUSSION -- 4.1 Spatial Variations -- 4.2 Denitrification -- 4.3 SEDIMENT CARBON AND NITROGEN -- 4.4 Primary Productivity. , 4.5 Leaf Litter C:N Analysis -- 5. SUMMARY AND CONCLUSIONS -- REFERENCES -- 14 Dissolved Metal Distribution in Indian Mangrove Ecosystem: Case Studies from East Coast of India -- 1. INTRODUCTION -- 2. MATERIALS AND METHODS -- 3. RESULTS AND DISCUSSION -- 4. CONCLUSION -- REFERENCES -- SECTION 4 Threats to Coastal Aquatic Ecosystems: Developmental and Sustainability Issues -- 15 Shrimp Culture: Trend, Consequences and Sustainability in the South-western Coastal Region of Bangladesh -- 1. INTRODUCTION -- 2. CURRENT STATE OF SHRIMP CULTURE -- 3. THE TRENDS -- 3.1 Trends in the Changes of Land-use Pattern -- 3.2 Trends in Employment Pattern -- 3.3 Trends in Yield, Export and Earnings -- 3.4 Trends in Local Supply Chain -- 4. THE CONSEQUENCES -- 4.1 Consequences on the Physical Environment -- 4.2 Consequences on the Biological Environment -- 4.3 Societal and Economic Consequences -- 5. THE BLUE REVOLUTION: A REALITY CHECK -- 6. THE ISSUE OF SUSTAINABILITY: ENVIRONMENTAL CONCERNS -- 7. THE MEASURES FOR SUSTAINABILITY: POLICY AND LEGAL ISSUES -- 8. CONCLUSION -- REFERENCES -- 16 Role of Sand Dunes and Mangroves in the Mitigation of Coastal Hazards with Reference to 2004 Tsunami -- 1. INTRODUCTION -- 2. SAND DUNES -- 2.1 Sand Dunes Saved the Villages -- 2.2 Saving the Sand Dunes -- 2.2.1 Dune Grass Planting -- 2.2.2 Dune Thatching -- 2.2.3 Sand Bag Structures -- 2.2.4 Public Awareness and Community-based Participation -- 3. MANGROVES -- 3.1 Causes of Depletion -- 3.2 Mangroves - Life Saving Role -- 3.3 Protecting Mangroves -- 4. MODEL PLAN -- 5. CONCLUSION -- REFERENCES -- 17 Assessment of Potential Health Risk through Arsenic Flow in FoodChain-A Study in Gangetic Delta of West Bengal -- 1. INTRODUCTION -- 2. MATERIALS AND METHODS -- 2.1 Teflon Bomb Digestion of Vegetable and Crop Samples -- 2.2 Sample Analysis -- 3. RESULTS. , 3.1 Bioaccumulation of Arsenic in Cereals and Pulses.
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  • 3
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    Unbekannt
    ACS Puplications
    In:  Environmental Science & Technology, 46 (8). pp. 4419-4426.
    Publikationsdatum: 2021-02-22
    Beschreibung: Coagulation of dissolved organic matter (DOM) by hydrolyzing metals is an important environmental process with particular relevance, e.g., for the cycling of organic matter in metal-rich aquatic systems or the flocculation of organic matter in wastewater treatment plants. Often, a nonremovable fraction of DOM remains in solution even at low DOM/metal ratios. Because coagulation by metals results from interactions with functional groups, we hypothesize that noncoagulating fractions have a distinct molecular composition. To test the hypothesis, we analyzed peat-derived dissolved organic matter remaining in solution after mixing with salts of Ca, Al, and Fe using 15 T Electrospray Ionization Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry (ESI-FT-ICR-MS). Addition of metals resulted in a net removal of DOM. Also a reduction of molecular diversity was observed, as the number of peaks from the ESI-FT-ICR-MS spectra decreased. At DOM/metal ratios of ∼9 Ca did not show any preference for distinct molecular fractions, while Fe and Al removed preferentially the most oxidized compounds (O/C ratio 〉0.4) of the peat leachate. Lowering DOM/metal ratios to ∼1 resulted in further removal of less oxidized as well as more aromatic compounds (“black carbon”). Molecular composition in the residual solution after coagulation was more saturated, less polar, and less oxidized compared to the original peat leachate and exhibited a surprising similarity with DOM of marine origin. By identifying more than 9200 molecular formulas we can show that structural properties (saturation and aromaticity) and oxygen content of individual DOM molecules play an important role in coagulation with metals. We conclude that polyvalent cations not only alter the net mobility but also the very molecular composition of DOM in aquatic environments.
    Materialart: Article , PeerReviewed
    Format: text
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  • 4
    Publikationsdatum: 2019-09-23
    Beschreibung: The tropical South East Pacific is characterized by strong coastal upwelling on the narrow continental shelf and an intense oxygen minimum zone (OMZ) in the intermediate water layer. These hydrographic properties are responsible for a permanent supply of intermediate water masses to the surface rich in nutrients and with a remarkably low inorganic N:P stoichiometry. To investigate the impact of OMZ-influenced upwelling waters on phytoplankton growth, elemental and taxonomical composition we measured hydrographic and biogeochemical parameters along an east–west transect at 10°S in the tropical South East Pacific, stretching from the upwelling region above the narrow continental shelf to the well-stratified oceanic section of the eastern boundary regime. New production in the area of coastal upwelling was driven by large-sized phytoplankton (e.g. diatoms) with generally low N:P ratios (〈16:1). While nitrate and phosphate concentrations were at levels not limiting phytoplankton growth along the entire transect, silicate depletion prohibited diatom growth further off-shore. A deep chlorophyll a maximum consisting of pico-/nano- (Synechococcus, flagellates) and microphytoplankton occurred within a pronounced thermocline in subsurface waters above the shelf break and showed intermediate N:P ratios close to Redfield proportions. High PON:POP (〉20:1) ratios were observed in the stratified open ocean section of the transect, coinciding with the abundance of two strains of the pico-cyanobacterium Prochlorococcus; a high-light adapted strain in the surface layer and a low-light adapted strain occurring along the oxic-anoxic transition zone below the thermocline. Excess phosphate present along the entire transect did not appear to stimulate growth of nitrogen-fixing phytoplankton, as pigment fingerprinting did not indicate the presence of diazotrophic cyanobacteria at any of our sampling stations. Instead, a large fraction of the excess phosphate generated within the oxygen minimum zone was consumed by non-Redfield production of large phytoplankton in shelf surface waters.
    Materialart: Article , PeerReviewed
    Format: text
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  • 5
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    Unbekannt
    PANGAEA
    In:  Supplement to: Bienhold, Christina; Pop Ristova, Petra; Wenzhöfer, Frank; Dittmar, Thorsten; Boetius, Antje (2013): How deep-sea wood falls sustain chemosynthetic life. PLoS ONE, 8(1), e53590, https://doi.org/10.1371/journal.pone.0053590
    Publikationsdatum: 2023-05-12
    Beschreibung: Large organic food falls to the deep sea - such as whale carcasses and wood logs - support the development of reduced, sulfidic niches in an otherwise oxygenated, oligotrophic deep-sea environment. These transient hot spot ecosystems may serve the dispersal of highly adapted chemosynthetic organisms such as thiotrophic bivalves and siboglinid worms. Here we investigated the biogeochemical and microbiological processes leading to the development of sulfidic niches. Wood colonization experiments were carried out for the duration of one year in the vicinity of a cold seep area in the Nile deep-sea fan (Eastern Mediterranean) at depths of 1690 m. Wood logs were deployed in 2006 during the BIONIL cruise (RV Meteor M70/2 with ROV Quest, Marum, Germany) and sampled in 2007 during the Medeco-2 cruise (RV Pourquoi Pas? with ROV Victor 6000, Ifremer, France). Wood-boring bivalves played a key role in the initial degradation of the wood, the dispersal of wood chips and fecal matter around the wood log, and the provision of colonization surfaces to other organisms. Total oxygen uptake measured with a ROV-operated benthic chamber module was higher at the wood (0.5 m away) in contrast to 10 m away at a reference site (25 mmol m-2 d-1 and 1 mmol m-2 d-1, respectively), indicating an increased activity of sedimentary communities around the wood falls. Bacterial cell numbers associated with wood increased substantially from freshly submerged wood to the wood chip/fecal matter layer next to the wood experiments, as determined with Acridine Orange Direct Counts (AODC) and DAPI-stained counts. Microsensor measurements of sulfide, oxygen and pH were conducted ex situ. Sulfide fluxes were higher at the wood experiments when compared to reference measurements (19 and 32 mmol m-2 d-1 vs. 0 and 16 mmol -2 d-1, respectively). Sulfate reduction (SR) rates at the wood experiments were determined in ex situ incubations (1.3 and 2.0 mmol m-2 d-1) and fell into the lower range of SR rates previously observed from other chemosynthetic habitats at cold seeps. There was no influence of wood deposition on phosphate, silicate and nitrate concentrations, but ammonium concentrations were elevated at the wood chip-sediment boundary layer. Concentrations of dissolved organic carbon were much higher at the wood experiments (wood chip-sediment boundary layer) in comparison to measurements at the reference sites, which may indicate that cellulose degradation was highest under anoxic conditions and hence enabled by anaerobic benthic bacteria, e.g. fermenters and sulfate reducers. Our observations demonstrate that, after one year, the presence of wood at the seafloor had led to the creation of sulfidic niches, comparable to what has been observed at whale falls, albeit at lower rates.
    Schlagwort(e): CHEMECO; HERMES; HERMIONE; Hotspot Ecosystem Research and Mans Impact On European Seas; Hotspot Ecosystem Research on the Margins of European Seas; Monitoring colonisation processes in chemosynthetic ecosystems
    Materialart: Dataset
    Format: application/zip, 11 datasets
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  • 6
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    Unbekannt
    PANGAEA
    In:  Supplement to: Koch, Boris P; Witt, Matthias; Engbrodt, Ralph; Dittmar, Thorsten; Kattner, Gerhard (2005): Molecular formulae of marine and terrigenous dissolved organic matter detected by electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry. Geochimica et Cosmochimica Acta, 69(13), 3299-3308, https://doi.org/10.1016/j.gca.2005.02.027
    Publikationsdatum: 2023-10-28
    Beschreibung: The chemical structure of refractory marine dissolved organic matter (DOM) is still largely unknown. Electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (ESI FT-ICR-MS) was used to resolve the complex mixtures of DOM and provide valuable information on elemental compositions on a molecular scale. We characterized and compared DOM from two sharply contrasting aquatic environments, algal-derived DOM from the Weddell Sea (Antarctica) and terrigenous DOM from pore water of a tropical mangrove area in northern Brazil. Several thousand molecular formulas in the mass range of 300-600 Da were identified and reproduced in element ratio plots. On the basis of molecular elemental composition and double-bond equivalents (DBE) we calculated an average composition for marine DOM. O/C ratios in the marine samples were lower (0.36 ± 0.01) than in the mangrove pore-water sample (0.42). A small proportion of chemical formulas with higher molecular mass in the marine samples were characterized by very low O/C and H/C ratios probably reflecting amphiphilic properties. The average number of unsaturations in the marine samples was surprisingly high (DBE = 9.9; mangrove pore water: DBE = 9.4) most likely due to a significant contribution of carbonyl carbon. There was no significant difference in elemental composition between surface and deep-water DOM in the Weddell Sea. Although there were some molecules with unique marine elemental composition, there was a conspicuous degree of similarity between the terrigenous and algal-derived end members. Approximately one third of the molecular formulas were present in all marine as well as in the mangrove samples. We infer that different forms of microbial degradation ultimately lead to similar structural features that are intrinsically refractory, independent of the source of the organic matter and the environmental conditions where degradation took place.
    Schlagwort(e): ANT-XIX/2; AWI; Caete_mangr; Carbon, organic, dissolved; CTD, Seabird; CTD-R; Date/Time of event; DEPTH, water; Equatorial West Atlantic; Event label; High temperature catalytic oxidation; Latitude of event; Longitude of event; Percentage; Polarstern; Priority Programme 1158 Antarctic Research with Comparable Investigations in Arctic Sea Ice Areas; PS61; PS61/024-1; PS61/027-1; PS61/031-1; Salinity; Sample type; SPP1158; Station label; Water sample; Weddell Sea; WS
    Materialart: Dataset
    Format: text/tab-separated-values, 35 data points
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  • 7
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    Unbekannt
    PANGAEA
    In:  Supplement to: Franz, Jasmin; Hauss, Helena; Sommer, Ulrich; Dittmar, Thorsten; Riebesell, Ulf (2012): Production, partitioning and stoichiometry of organic matter under variable nutrient supply during mesocosm experiments in the tropical Pacific and Atlantic Ocean. Biogeosciences, 9(11), 4629-4643, https://doi.org/10.5194/bg-9-4629-2012
    Publikationsdatum: 2023-10-28
    Beschreibung: Oxygen-deficient waters in the ocean, generally referred to as oxygen minimum zones (OMZ), are expected to expand as a consequence of global climate change. Poor oxygenation is promoting microbial loss of inorganic nitrogen (N) and increasing release of sediment-bound phosphate (P) into the water column. These intermediate water masses, nutrient-loaded but with an N deficit relative to the canonical N:P Redfield ratio of 16:1, are transported via coastal upwelling into the euphotic zone. To test the impact of nutrient supply and nutrient stoichiometry on production, partitioning and elemental composition of dissolved (DOC, DON, DOP) and particulate (POC, PON, POP) organic matter, three nutrient enrichment experiments were conducted with natural microbial communities in shipboard mesocosms, during research cruises in the tropical waters of the southeast Pacific and the northeast Atlantic. Maximum accumulation of POC and PON was observed under high N supply conditions, indicating that primary production was controlled by N availability. The stoichiometry of microbial biomass was unaffected by nutrient N:P supply during exponential growth under nutrient saturation, while it was highly variable under conditions of nutrient limitation and closely correlated to the N:P supply ratio, although PON:POP of accumulated biomass generally exceeded the supply ratio. Microbial N:P composition was constrained by a general lower limit of 5:1. Channelling of assimilated P into DOP appears to be the mechanism responsible for the consistent offset of cellular stoichiometry relative to inorganic nutrient supply and nutrient drawdown, as DOP build-up was observed to intensify under decreasing N:P supply. Low nutrient N:P conditions in coastal upwelling areas overlying O2-deficient waters seem to represent a net source for DOP, which may stimulate growth of diazotrophic phytoplankton. These results demonstrate that microbial nutrient assimilation and partitioning of organic matter between the particulate and the dissolved phase are controlled by the N:P ratio of upwelled nutrients, implying substantial consequences for nutrient cycling and organic matter pools in the course of decreasing nutrient N:P stoichiometry.
    Schlagwort(e): Climate - Biogeochemistry Interactions in the Tropical Ocean; SFB754
    Materialart: Dataset
    Format: application/zip, 3 datasets
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  • 8
    Publikationsdatum: 2023-10-28
    Schlagwort(e): Biogenic silica; Carbon, organic, dissolved; Carbon, organic, particulate; Climate - Biogeochemistry Interactions in the Tropical Ocean; DATE/TIME; M77/3; M77/3-mesocosm; MESO; Mesocosm experiment; Meteor (1986); Nitrogen, organic, dissolved; Nitrogen, organic, particulate; Nitrogen, total; Phosphorus, organic, dissolved; Phosphorus, organic, particulate; Phosphorus, total; Sample code/label; SFB754; Silicate; Transparent exopolymer particles; Treatment
    Materialart: Dataset
    Format: text/tab-separated-values, 1070 data points
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  • 9
    Publikationsdatum: 2024-05-22
    Schlagwort(e): Ammonium; Biogenic silica; Carbon, organic, particulate; Chlorophyll a; Climate - Biogeochemistry Interactions in the Tropical Ocean; DATE/TIME; Day of experiment; M80/2; M80/2-mesocosm; MESO; Mesocosm experiment; Meteor (1986); Nitrate; Nitrite; Nitrogen, organic, dissolved; Nitrogen, organic, particulate; Nitrogen, total; Phosphate; Phosphorus, organic, dissolved; Phosphorus, organic, particulate; Phosphorus, total; Sample code/label; SFB754; Silicate; Treatment
    Materialart: Dataset
    Format: text/tab-separated-values, 2192 data points
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  • 10
    Publikationsdatum: 2024-05-22
    Schlagwort(e): Ammonium; Carbon, organic, dissolved; Carbon, organic, particulate; Chlorophyll a; Climate - Biogeochemistry Interactions in the Tropical Ocean; DATE/TIME; M83/1; M83/1-mesocosm; MESO; Mesocosm experiment; Meteor (1986); Nitrate; Nitrite; Nitrogen, organic, dissolved; Nitrogen, organic, particulate; Phosphate; Phosphorus, organic, dissolved; Phosphorus, organic, particulate; Sample code/label; SFB754; Silicate; Treatment
    Materialart: Dataset
    Format: text/tab-separated-values, 1893 data points
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