Chemical Controls On The Cycling And Reactivity Of Marine Dissolved Organic Matter

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Chemical Controls on the Cycling and Reactivity of Marine Dissolved Organic Matter

Author : Benjamin Nash Granzow
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (143 download)

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Book Synopsis Chemical Controls on the Cycling and Reactivity of Marine Dissolved Organic Matter by : Benjamin Nash Granzow

Download or read book Chemical Controls on the Cycling and Reactivity of Marine Dissolved Organic Matter written by Benjamin Nash Granzow and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine dissolved organic matter (DOM) is an actively cycling reservoir of carbon containing thousands of unique compounds. To describe the complex dynamics that govern the biological transformation and decomposition of compounds in this molecular black box, models of DOM reactivity use chemical characteristics, as well as environmental parameters, to describe trends in the turnover time of classes of DOM. In this thesis, I describe two projects that examine hypotheses regarding the turnover of two classes of DOM. In the 1st project, I test the assumption made by the size-reactivity continuum hypothesis that high molecular weight (> 1 kDa) DOM (HMWDOM) represents a diagenetic intermediate between large labile material and small recalcitrant compounds. Size-fractions of HMWDOM were collected using size-exclusion chromatography, and the changes in MW and chemical composition of the fractions were studied using diffusion-ordered spectroscopy. The size fraction carbon isotopic values were correlated with the proportion of humic substances in the fractions. Through linear modeling, the apparent radiocarbon ages of the two major components of HMWDOM were determined to be 1-3 yrs and 2-4 kyrs, respectively. Combined with the measurements of MW distribution this work demonstrates that HMWDOM is composed of two components that have contrasting decomposition pathways in the ocean. HMWDOM cannot be treated as a single DOM pool when incorporated into models of DOM diagenesis. The 2nd project in this dissertation examines the remineralization of phosphonates, compounds with a direct C-P bond, in the lower euphotic zone using a newly developed fluorescent assay, which measures the activity of carbon-phosphorus lyase. C-P lyase activity (CLA) profiles from the North Pacific Subtropical Gyre (NPSG) showed a sharp activity maximum near the deep-chlorophyll maximum (DCM). High-resolution nutrient measurements suggest that this subsurface CLA maximum is the result of a high nitrate flux at the top of the nitracline. The composition of particulate-P through the euphotic zone was also examined. While phosphonates were not detected in suspended particles, a significant amount of aminoethylphosphonate was measured in sinking material, suggesting eukaryotic material may be an important source of phosphonates to the ocean.

Biogeochemistry of Marine Dissolved Organic Matter

Author : Dennis A. Hansell
Publisher : Academic Press
ISBN 13 : 0124071538
Total Pages : 712 pages
Book Rating : 4.1/5 (24 download)

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Book Synopsis Biogeochemistry of Marine Dissolved Organic Matter by : Dennis A. Hansell

Download or read book Biogeochemistry of Marine Dissolved Organic Matter written by Dennis A. Hansell and published by Academic Press. This book was released on 2014-10-02 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine dissolved organic matter (DOM) is a complex mixture of molecules found throughout the world's oceans. It plays a key role in the export, distribution, and sequestration of carbon in the oceanic water column, posited to be a source of atmospheric climate regulation. Biogeochemistry of Marine Dissolved Organic Matter, Second Edition, focuses on the chemical constituents of DOM and its biogeochemical, biological, and ecological significance in the global ocean, and provides a single, unique source for the references, information, and informed judgments of the community of marine biogeochemists. Presented by some of the world's leading scientists, this revised edition reports on the major advances in this area and includes new chapters covering the role of DOM in ancient ocean carbon cycles, the long term stability of marine DOM, the biophysical dynamics of DOM, fluvial DOM qualities and fate, and the Mediterranean Sea. Biogeochemistry of Marine Dissolved Organic Matter, Second Edition, is an extremely useful resource that helps people interested in the largest pool of active carbon on the planet (DOC) get a firm grounding on the general paradigms and many of the relevant references on this topic. Features up-to-date knowledge of DOM, including five new chapters The only published work to synthesize recent research on dissolved organic carbon in the Mediterranean Sea Includes chapters that address inputs from freshwater terrestrial DOM

Encyclopedia of Geochemistry

Author : William M. White
Publisher : Springer
ISBN 13 : 9783319393117
Total Pages : 1680 pages
Book Rating : 4.3/5 (931 download)

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Book Synopsis Encyclopedia of Geochemistry by : William M. White

Download or read book Encyclopedia of Geochemistry written by William M. White and published by Springer. This book was released on 2018-07-24 with total page 1680 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Encyclopedia is a complete and authoritative reference work for this rapidly evolving field. Over 200 international scientists, each experts in their specialties, have written over 330 separate topics on different aspects of geochemistry including geochemical thermodynamics and kinetics, isotope and organic geochemistry, meteorites and cosmochemistry, the carbon cycle and climate, trace elements, geochemistry of high and low temperature processes, and ore deposition, to name just a few. The geochemical behavior of the elements is described as is the state of the art in analytical geochemistry. Each topic incorporates cross-referencing to related articles, and also has its own reference list to lead the reader to the essential articles within the published literature. The entries are arranged alphabetically, for easy access, and the subject and citation indices are comprehensive and extensive. Geochemistry applies chemical techniques and approaches to understanding the Earth and how it works. It touches upon almost every aspect of earth science, ranging from applied topics such as the search for energy and mineral resources, environmental pollution, and climate change to more basic questions such as the Earth’s origin and composition, the origin and evolution of life, rock weathering and metamorphism, and the pattern of ocean and mantle circulation. Geochemistry allows us to assign absolute ages to events in Earth’s history, to trace the flow of ocean water both now and in the past, trace sediments into subduction zones and arc volcanoes, and trace petroleum to its source rock and ultimately the environment in which it formed. The earliest of evidence of life is chemical and isotopic traces, not fossils, preserved in rocks. Geochemistry has allowed us to unravel the history of the ice ages and thereby deduce their cause. Geochemistry allows us to determine the swings in Earth’s surface temperatures during the ice ages, determine the temperatures and pressures at which rocks have been metamorphosed, and the rates at which ancient magma chambers cooled and crystallized. The field has grown rapidly more sophisticated, in both analytical techniques that can determine elemental concentrations or isotope ratios with exquisite precision and in computational modeling on scales ranging from atomic to planetary.

Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters

Author : Christopher L. Osburn
Publisher : Frontiers Media SA
ISBN 13 : 2889450813
Total Pages : 244 pages
Book Rating : 4.8/5 (894 download)

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Book Synopsis Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters by : Christopher L. Osburn

Download or read book Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters written by Christopher L. Osburn and published by Frontiers Media SA. This book was released on 2017-01-17 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt: A substantial increase in the number of studies using the optical properties (absorbance and fluorescence) of dissolved organic matter (DOM) as a proxy for its chemical properties in estuaries and the coastal and open ocean has occurred during the last decade. We are making progress on finding the actual chemical compounds or phenomena responsible for DOM’s optical properties. Ultrahigh resolution mass spectrometry, in particular, has made important progress in making the key connections between optics and chemistry. But serious questions remain and the last major special issue on DOM optics and chemistry occurred nearly 10 years ago. Controversies remain from the non-specific optical properties of DOM that are not linked to discrete sources, and sometimes provide conflicting information. The use of optics, which is relatively easier to employ in synoptic and high resolution sampling to determine chemistry, is a critical connection to make and can lead to major advances in our understanding of organic matter cycling in all aquatic ecosystems. The contentions and controversies raised by our poor understanding of the linkages between optics and chemistry of DOM are bottlenecks that need to be addressed and overcome.

Biogeochemistry of Marine Dissolved Organic Matter

Author : Dennis A. Hansell
Publisher : Elsevier
ISBN 13 : 0443138591
Total Pages : 870 pages
Book Rating : 4.4/5 (431 download)

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Book Synopsis Biogeochemistry of Marine Dissolved Organic Matter by : Dennis A. Hansell

Download or read book Biogeochemistry of Marine Dissolved Organic Matter written by Dennis A. Hansell and published by Elsevier. This book was released on 2024-07-04 with total page 870 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biogeochemistry of Marine Dissolved Organic Matter, 3rd edition is the most up-to-date revision of the fundamental reference for the biogeochemistry of marine dissolved organic matter. Since its original publication in June 2002, the science, questions, and priorities have advanced, and the editors of this essential guide, have added nine new chapters, including one on the South China Sea. An indispensable manual edited by the most distinguished experts in the field, this book is addressed to graduate students, marine scientists, and all professionals interested in advancing their knowledge of the field. Features up-to-date knowledge on DOM, including 9 new chapters Presents the only published work to synthesize recent research on dissolved organic carbon in the South China, a region receiving a great deal of attention in recent decades Offers contributions by world-class research leaders

Chemical Characterization of Dissolved Organic Matter (DOM) in Seawater

Author : Tracy Michelle Quan
Publisher :
ISBN 13 :
Total Pages : 212 pages
Book Rating : 4.:/5 (61 download)

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Book Synopsis Chemical Characterization of Dissolved Organic Matter (DOM) in Seawater by : Tracy Michelle Quan

Download or read book Chemical Characterization of Dissolved Organic Matter (DOM) in Seawater written by Tracy Michelle Quan and published by . This book was released on 2005 with total page 212 pages. Available in PDF, EPUB and Kindle. Book excerpt: (Cont.) This new separation protocol utilized various chromatographic techniques, including cation exchange chromatography and high- pressure liquid chromatography (HPLC) using C18 and strong cation exchange (SCX) columns. Six amino acids were isolated from a HMWDOM sample with sufficient purity and quantity for radiocarbon analysis. These amino acids had a range of A'4C values, from 121%o to -454%o. The final section investigates biological controls on the dissolved organic nitrogen (DON) pool. Total hydrolyzable amino acids (THAA), and nucleic acids were measured for four incubations: a control incubation, a grazer added incubation, a zero virus incubation, and a 10 times virus incubation. Comparison to the control showed THAA and nucleic acid release were influenced by viruses but not grazers.

Aquatic Humic Substances

Author : Dag Hessen
Publisher : Springer Science & Business Media
ISBN 13 : 366203736X
Total Pages : 350 pages
Book Rating : 4.6/5 (62 download)

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Book Synopsis Aquatic Humic Substances by : Dag Hessen

Download or read book Aquatic Humic Substances written by Dag Hessen and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt: Humic substances occur in all kinds of aquatic systems, but are particularly important in northern, coniferous areas. They strongly modify the aquatic ecosystems and also constitute a major problem in the drinking water supply. This volume covers all aspects of aquatic humic substances, from their origin and chemical properties, their effects on light and nutrient regimes and biogeochemical cycling, to their role regarding organisms, productivity and food web organization from bacteria to fish. Special emphasis is paid to carbon cycling and food web organization in humic lakes, but aspects of marine carbon cycling related to humus are treated as well.

Microbial Utilization and Transformation of Dissolved Organic Matter in Aquatic Environments - from Streams to the Deep Ocean

Author : Johanna Sjöstedt
Publisher : Frontiers Media SA
ISBN 13 : 2889711021
Total Pages : 255 pages
Book Rating : 4.8/5 (897 download)

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Book Synopsis Microbial Utilization and Transformation of Dissolved Organic Matter in Aquatic Environments - from Streams to the Deep Ocean by : Johanna Sjöstedt

Download or read book Microbial Utilization and Transformation of Dissolved Organic Matter in Aquatic Environments - from Streams to the Deep Ocean written by Johanna Sjöstedt and published by Frontiers Media SA. This book was released on 2021-07-28 with total page 255 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Aquatic Ecosystems: Interactivity of Dissolved Organic Matter

Author : Stuart Findlay
Publisher : Academic Press
ISBN 13 : 0122563719
Total Pages : 534 pages
Book Rating : 4.1/5 (225 download)

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Book Synopsis Aquatic Ecosystems: Interactivity of Dissolved Organic Matter by : Stuart Findlay

Download or read book Aquatic Ecosystems: Interactivity of Dissolved Organic Matter written by Stuart Findlay and published by Academic Press. This book was released on 2003 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Overviews of the source, supply and variability of DOM, surveys of the processes that mediate inputs to microbial food webs, and syntheses consolidating research findings provide a comprehensive review of what is known of DOM in freshwater. This book will be important to anyone interested in understanding the fundamental factors associated with DOM that control aquatic ecosystems."--BOOK JACKET.

Microbial Cycling of Marine High Molecular Weight Dissolved Organic Matter

Author : Oscar Abraham Sosa
Publisher :
ISBN 13 :
Total Pages : 246 pages
Book Rating : 4.:/5 (956 download)

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Book Synopsis Microbial Cycling of Marine High Molecular Weight Dissolved Organic Matter by : Oscar Abraham Sosa

Download or read book Microbial Cycling of Marine High Molecular Weight Dissolved Organic Matter written by Oscar Abraham Sosa and published by . This book was released on 2016 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Microorganisms play a central role mediating biogeochemical cycles in the ocean. Marine dissolved organic matter (DOM) – a reservoir of organic solutes and colloids derived from plankton is a major source of carbon, nutrients, and energy to microbial communities. The biological transformation and remineralization of DOM sustains marine productivity by linking the microbial food web to higher trophic levels (the microbial loop) and exerts important controls over the cycles of carbon and bioessential elements, such as nitrogen and phosphorus, in the sea. Yet insight into the underlying metabolism and reactions driving the degradation of DOM is limited partly because its exact molecular composition is difficult to constrain and appropriate microbial model systems known to decompose marine DOM are lacking. This thesis identifies marine microorganisms that can serve as model systems to study the metabolic pathways and biochemical reactions that control an important ecosystem function, DOM turnover. To accomplish this goal, bacterial isolates were obtained by enriching seawater in dilution-to-extinction culturing experiments with a natural source of DOM, specifically, the high molecular weight (HMW) fraction (>1 kDa nominal molecular weight) obtained by ultrafiltration. Because it is relatively easy to concentrate and it is fairly uniform in its chemical composition across the global ocean and other aquatic environments, HMW DOM has the potential to serve as a model growth substrate to study the biological breakdown of DOM. The phylogeny, genomes, and growth characteristics of the organisms identified through this work indicate that HMW DOM contains bioavailable substrates that may support widespread microbial populations in coastal and open-ocean environments. The availability of ecologically relevant isolates in culture can now serve to test hypothesis emerging from cultivation-independent studies pertaining the potential role of microbial groups in the decomposition of organic matter in the sea. Detailed studies of the biochemical changes exerted on DOM by selected bacterial strains will provide new insight into the processes driving the aerobic microbial food chain in the upper ocean.

Acquisition, Degradation, and Cycling of Organic Matter Within Sea-ice Brines by Bacteria and Their Viruses

Author : Gordon Maxwell Showalter
Publisher :
ISBN 13 :
Total Pages : 11 pages
Book Rating : 4.:/5 (124 download)

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Book Synopsis Acquisition, Degradation, and Cycling of Organic Matter Within Sea-ice Brines by Bacteria and Their Viruses by : Gordon Maxwell Showalter

Download or read book Acquisition, Degradation, and Cycling of Organic Matter Within Sea-ice Brines by Bacteria and Their Viruses written by Gordon Maxwell Showalter and published by . This book was released on 2020 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine dissolved organic carbon (DOC) is a major component of the global carbon pool, and thus can have significant effects on global carbon cycling. Within the oceans, DOC is largely regulated by microbial communities, which can serve as both a source and sink of organic carbon. Microbial controls on DOC cycling within sea ice are especially relevant to global processes, as sea ice can act as an inhibitor of exchange between the ocean and the atmosphere while also affecting carbon export to the deep sea. However, how sea-ice communities influence DOC cycling, especially in very cold conditions of winter sea ice, is poorly understood. This dissertation explores how bacterial communities, which dominate winter sea ice, may influence DOC cycling. Chapter 1 presents an introduction of sea-ice microbial communities in the low-temperature, high salinity conditions which characterize sea-ice brines. How bacteria within brines swim in response to temperature, salinity, and chemical gradients in sea ice is presented in Chapter 2, which demonstrates a low-temperature record for directed bacterial swimming and suggests explanations for how bacteria position themselves within brines to access DOC. However, most DOC within the marine environment is too large for bacterial uptake, necessitating degradation by enzymes. Chapter 3 demonstrates bacterial extracellular enzyme activity both in a laboratory setting and in situ, showing growth-dependent enzyme activity down to -8°C and up to 142 ppt salts and across a freeze-thaw cycle within sea ice and sea-surface microlayer samples. Finally, Chapter 4 presents a model of bacterially and virally mediated DOC cycling. This model uses simple differential equations, explained further in Appendix 1, to probe the potential existence of a viral shunt within sea-ice brines by demonstrating the role of bacteriophage in population dynamics of a theoretical brine, suggesting low viral production, high host-specificity, and virally-driven DOC cycling may be common within this environment. The results of this dissertation have implications for the understanding of DOC within polar seas and demonstrate the potential for active DOC cycling mediated by bacteria and their viruses within winter sea ice, which serves as an analog for very cold ice elsewhere.

Deep Carbon

Author : Beth N. Orcutt
Publisher : Cambridge University Press
ISBN 13 : 1108477496
Total Pages : 687 pages
Book Rating : 4.1/5 (84 download)

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Book Synopsis Deep Carbon by : Beth N. Orcutt

Download or read book Deep Carbon written by Beth N. Orcutt and published by Cambridge University Press. This book was released on 2019-10-17 with total page 687 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive guide to carbon inside Earth - its quantities, movements, forms, origins, changes over time and impact on planetary processes. This title is also available as Open Access on Cambridge Core.

Marine Organic Chemistry

Author : E.K. Duursma
Publisher : Elsevier
ISBN 13 : 0080870694
Total Pages : 534 pages
Book Rating : 4.0/5 (88 download)

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Book Synopsis Marine Organic Chemistry by : E.K. Duursma

Download or read book Marine Organic Chemistry written by E.K. Duursma and published by Elsevier. This book was released on 2011-09-22 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine Organic Chemistry

Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters

Author :
Publisher :
ISBN 13 :
Total Pages : 0 pages
Book Rating : 4.:/5 (136 download)

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Book Synopsis Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters by :

Download or read book Linking Optical and Chemical Properties of Dissolved Organic Matter in Natural Waters written by and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A substantial increase in the number of studies using the optical properties (absorbance and fluorescence) of dissolved organic matter (DOM) as a proxy for its chemical properties in estuaries and the coastal and open ocean has occurred during the last decade. We are making progress on finding the actual chemical compounds or phenomena responsible for DOM's optical properties. Ultrahigh resolution mass spectrometry, in particular, has made important progress in making the key connections between optics and chemistry. But serious questions remain and the last major special issue on DOM optics and chemistry occurred nearly 10 years ago. Controversies remain from the non-specific optical properties of DOM that are not linked to discrete sources, and sometimes provide conflicting information. The use of optics, which is relatively easier to employ in synoptic and high resolution sampling to determine chemistry, is a critical connection to make and can lead to major advances in our understanding of organic matter cycling in all aquatic ecosystems. The contentions and controversies raised by our poor understanding of the linkages between optics and chemistry of DOM are bottlenecks that need to be addressed and overcome.

Chemical Characterization of Dissolved Organic Matter (DOM) in Seawater

Author :
Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (659 download)

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Book Synopsis Chemical Characterization of Dissolved Organic Matter (DOM) in Seawater by :

Download or read book Chemical Characterization of Dissolved Organic Matter (DOM) in Seawater written by and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Funding for this research was provided by the National Science Foundation (OCE-981 8654) and the Department of Energy (DEFG0200ERG62999). Student support was also provided by a National Science Foundation Graduate Student Fellowship.

Aquatic Organic Matter Fluorescence

Author : Paula G. Coble
Publisher : Cambridge University Press
ISBN 13 : 0521764610
Total Pages : 407 pages
Book Rating : 4.5/5 (217 download)

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Book Synopsis Aquatic Organic Matter Fluorescence by : Paula G. Coble

Download or read book Aquatic Organic Matter Fluorescence written by Paula G. Coble and published by Cambridge University Press. This book was released on 2014-07-14 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: A core text on principles, laboratory/field methodologies, and data interpretation for fluorescence applications in aquatic science, for advanced students and researchers.

Microbial Ecology of the Oceans

Author : Josep M. Gasol
Publisher : John Wiley & Sons
ISBN 13 : 1119107202
Total Pages : 663 pages
Book Rating : 4.1/5 (191 download)

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Book Synopsis Microbial Ecology of the Oceans by : Josep M. Gasol

Download or read book Microbial Ecology of the Oceans written by Josep M. Gasol and published by John Wiley & Sons. This book was released on 2018-01-31 with total page 663 pages. Available in PDF, EPUB and Kindle. Book excerpt: The newly revised and updated third edition of the bestselling book on microbial ecology in the oceans The third edition of Microbial Ecology of the Oceans features new topics, as well as different approaches to subjects dealt with in previous editions. The book starts out with a general introduction to the changes in the field, as well as looking at the prospects for the coming years. Chapters cover ecology, diversity, and function of microbes, and of microbial genes in the ocean. The biology and ecology of some model organisms, and how we can model the whole of the marine microbes, are dealt with, and some of the trophic roles that have changed in the last years are discussed. Finally, the role of microbes in the oceanic P cycle are presented. Microbial Ecology of the Oceans, Third Edition offers chapters on The Evolution of Microbial Ecology of the Ocean; Marine Microbial Diversity as Seen by High Throughput Sequencing; Ecological Significance of Microbial Trophic Mixing in the Oligotrophic Ocean; Metatranscritomics and Metaproteomics; Advances in Microbial Ecology from Model Marine Bacteria; Marine Microbes and Nonliving Organic Matter; Microbial Ecology and Biogeochemistry of Oxygen-Deficient Water Columns; The Ocean’s Microscale; Ecological Genomics of Marine Viruses; Microbial Physiological Ecology of The Marine Phosphorus Cycle; Phytoplankton Functional Types; and more. A new and updated edition of a key book in aquatic microbial ecology Includes widely used methodological approaches Fully describes the structure of the microbial ecosystem, discussing in particular the sources of carbon for microbial growth Offers theoretical interpretations of subtropical plankton biogeography Microbial Ecology of the Oceans is an ideal text for advanced undergraduates, beginning graduate students, and colleagues from other fields wishing to learn about microbes and the processes they mediate in marine systems.