On the Role of Bacteria in the Cycling of Dissolved Organic Matter in the Sea

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Publisher :
ISBN 13 :
Total Pages : 350 pages
Book Rating : 4.:/5 (318 download)

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Book Synopsis On the Role of Bacteria in the Cycling of Dissolved Organic Matter in the Sea by : Robert Edward Hodson

Download or read book On the Role of Bacteria in the Cycling of Dissolved Organic Matter in the Sea written by Robert Edward Hodson and published by . This book was released on 1977 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Biogeochemistry of Marine Dissolved Organic Matter

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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

Aquatic Humic Substances

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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

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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:

Cycling of DOC and DON by Novel Heterotrophic and Photoheterotrophic Bacteria in the Ocean

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (953 download)

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Book Synopsis Cycling of DOC and DON by Novel Heterotrophic and Photoheterotrophic Bacteria in the Ocean by :

Download or read book Cycling of DOC and DON by Novel Heterotrophic and Photoheterotrophic Bacteria in the Ocean written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The flux of dissolved organic matter (DOM) through aquatic bacterial communities is a major process in carbon cycling in the oceans and other aquatic systems. Our work addressed the general hypothesis that the phylogenetic make-up of bacterial communities and the abundances of key types of bacteria are important factors influencing the processing of DOM in aquatic ecosystems. Since most bacteria are not easily cultivated, the phylogenetic diversity of these microbes has to be assessed using culture-independent approaches. Even if the relevant bacteria were cultivated, their activity in the lab would likely differ from that under environmental conditions. This project found variation in DOM uptake by the major bacterial groups found in coastal waters. In brief, the data suggest substantial differences among groups in the use of high and molecular weight DOM components. It also made key discoveries about the role of light in affecting this uptake especially by cyanobacteria. In the North Atlantic Ocean, for example, over half of the light-stimulated uptake was by the coccoid cyanobacterium, Prochlorococcus, with the remaining uptake due to Synechococcus and other photoheterotrophic bacteria. The project also examined in detail the degradation of one organic matter component, chitin, which is often said to be the second most abundant compound in the biosphere. The findings of this project contribute to our understanding of DOM fluxes and microbial dynamics supported by those fluxes. It is possible that these findings will lead to improvements in models of the carbon cycle that have compartments for dissolved organic carbon (DOC), the largest pool of organic carbon in the oceans.

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

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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.

Flows of Energy and Materials in Marine Ecosystems

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Publisher : Springer Science & Business Media
ISBN 13 : 1475703872
Total Pages : 722 pages
Book Rating : 4.4/5 (757 download)

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Book Synopsis Flows of Energy and Materials in Marine Ecosystems by : M. J. R. Fasham

Download or read book Flows of Energy and Materials in Marine Ecosystems written by M. J. R. Fasham and published by Springer Science & Business Media. This book was released on 2013-03-09 with total page 722 pages. Available in PDF, EPUB and Kindle. Book excerpt: The impetus for the conference held at Bombannes, France in May, 1982 arose out of a Scientific Committee on Oceanic Research (SCOR) Working Group on "Mathematical Models in Biological Oceanography". This group was chaired by K.H. Mann and held two meetings in 1977 and 1979. At both meetings it was felt that, although reductionist modelling of marine ecosystems had achieved some successes, the future progress lay in the development of holistic ecosystem models. The members of the group (K.H. Mann, T. Platt, J.M. Colebrook, D.F. Smith, M.J.R. Fasham, J. Field, G. Radach, R.E. Ulanowicz and F. Wulff) produced a critical review of reductionist and holistic models which was published by the Unesco Press (Platt, Mann and Ulanowicz, 1981). One of the conclusions of this review was that, whether holistic or reductionist models are preferred, it is critically important to increase the scientific effort in the measurement of physiological rates for the computation of ecological fluxes. The Working Group therefore recommended that an international meeting should be organized which would attempt to bring together theoretical ecologists and biological oceanographers to assess the present and future capability for measuring ecological fluxes and incorporating these data into models. An approach was made to the Marine Sciences Panel of the NATO Science Committee who expressed an interest in funding such a meeting. They awarded a planning grant and a planning group was formed consisting of M.J.R. Fasham, M.V. Angel, T. Platt, R.E.

Biogeochemistry of Marine Dissolved Organic Matter

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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

Microbial Cycling of Marine High Molecular Weight Dissolved Organic Matter

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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.

The Organic Carbon Cycle in the Arctic Ocean

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Publisher : Springer Science & Business Media
ISBN 13 : 3642189121
Total Pages : 394 pages
Book Rating : 4.6/5 (421 download)

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Book Synopsis The Organic Carbon Cycle in the Arctic Ocean by : Rüdiger Stein

Download or read book The Organic Carbon Cycle in the Arctic Ocean written by Rüdiger Stein and published by Springer Science & Business Media. This book was released on 2011-06-27 with total page 394 pages. Available in PDF, EPUB and Kindle. Book excerpt: The flux, preservation, and accumulation of organic carbon in marine systems are controlled by various mechanisms including primary p- duction of the surface water, supply of terrigenous organic matter from the surrounding continents, biogeochemical processes in the water column and at the seafloor, and sedimentation rate. For the world's oceans, phytoplankton productivity is by far the largest organic carbon 9 source, estimated to be about 30 to 50 Gt (10 tonnes) per year (Berger et al. 1989; Hedges and Keil 1995). By comparison, rivers contribute -1 about 0. 15 to 0. 23 Gt y of particulate organi.

The Chemistry of Microbiomes

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Publisher : National Academies Press
ISBN 13 : 0309458390
Total Pages : 133 pages
Book Rating : 4.3/5 (94 download)

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Book Synopsis The Chemistry of Microbiomes by : National Academies of Sciences, Engineering, and Medicine

Download or read book The Chemistry of Microbiomes written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2017-07-19 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: The 21st century has witnessed a complete revolution in the understanding and description of bacteria in eco- systems and microbial assemblages, and how they are regulated by complex interactions among microbes, hosts, and environments. The human organism is no longer considered a monolithic assembly of tissues, but is instead a true ecosystem composed of human cells, bacteria, fungi, algae, and viruses. As such, humans are not unlike other complex ecosystems containing microbial assemblages observed in the marine and earth environments. They all share a basic functional principle: Chemical communication is the universal language that allows such groups to properly function together. These chemical networks regulate interactions like metabolic exchange, antibiosis and symbiosis, and communication. The National Academies of Sciences, Engineering, and Medicine's Chemical Sciences Roundtable organized a series of four seminars in the autumn of 2016 to explore the current advances, opportunities, and challenges toward unveiling this "chemical dark matter" and its role in the regulation and function of different ecosystems. The first three focused on specific ecosystemsâ€"earth, marine, and humanâ€"and the last on all microbiome systems. This publication summarizes the presentations and discussions from the seminars.

Contributions of Abundant Bacterial Groups to the Flux of Dissolved Organic Matter in the Ocean

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Publisher :
ISBN 13 : 9780542458057
Total Pages : pages
Book Rating : 4.4/5 (58 download)

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Book Synopsis Contributions of Abundant Bacterial Groups to the Flux of Dissolved Organic Matter in the Ocean by : Rex R. Malmstrom

Download or read book Contributions of Abundant Bacterial Groups to the Flux of Dissolved Organic Matter in the Ocean written by Rex R. Malmstrom and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bacterioplankton communities play a crucial role marine biogeochemical cycles because they mediate the flux of dissolved organic matter (DOM), which is equal to about half of primary production in the ocean. These bacterial communities are also known to be incredibly diverse and comprised of bacteria from several different phylogenetic groups. However, the relationship between microbial diversity and biogeochemical cycling remains unclear. My dissertation focused on determining the contributions of abundant bacterial phylogenetic groups to the biogeochemical flux of DOM in the ocean. One specific goal if this dissertation was the identification and quantification of bacteria that assimilate the organic sulfur compound dimethylsulfoniopropionate (DMSP). DMSP can be hydrolyzed to produce dimethylsulfide (DMS), a sulfurous gas hypothesized to moderate changes in global temperature. However, most dissolved DMSP is assimilated into bacterial biomass, a process that satisfies nearly all of the bacterial S demand in the surface waters of the ocean. Since the biogeochemical fate of DMSP can affect either climate regulation or S transfer through marine food webs, it is important to identify bacteria that metabolize DMSP. To identify and quantify bacteria assimilating DMSP, I used a combination of micro-autoradiography and fluorescence in situ hybridization (Micro-FISH) to follow 35 S-DMSP assimilation into marine bacterial communities. In addition to DMSP flux, I also investigated the ecological activity of SAR11 bacteria. Gene sequences belonging to the SAR11 clade typically dominate 16S rRNA clone libraries from the ocean, and investigations with fluorescence in situ hybridization confirm that SAR11 bacteria often make up 25--35% of bacterioplankton communities. (Abstract shortened by UMI.).

Aquatic Ecosystems: Interactivity of Dissolved Organic Matter

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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.

Structure and Function of Microbial Communities Processing Dissolved Organic Matter in Marine Environments

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Publisher :
ISBN 13 : 9789570516012
Total Pages : 127 pages
Book Rating : 4.5/5 (16 download)

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Book Synopsis Structure and Function of Microbial Communities Processing Dissolved Organic Matter in Marine Environments by : Hila Elifantz

Download or read book Structure and Function of Microbial Communities Processing Dissolved Organic Matter in Marine Environments written by Hila Elifantz and published by . This book was released on 2007 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: The current study added to the growing information regarding the composition of bacterial community in aquatic environments and the role of specific bacterial groups in DOM assimilation. In particular, this study was the first to unfold the relation between structure and function of the bacterial community in the Arctic Ocean, the only cold environment studied in that aspect to date. The molecular study of GH5 revealed the potential of the community for polysaccharides degradation, however, more need to be done to broaden our understanding of the mineralization of these compounds in the marine environment.

Dissolved Organic Matter in Lacustrine Ecosystems

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Publisher : Springer Science & Business Media
ISBN 13 : 9401124744
Total Pages : 292 pages
Book Rating : 4.4/5 (11 download)

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Book Synopsis Dissolved Organic Matter in Lacustrine Ecosystems by : K. Salonen

Download or read book Dissolved Organic Matter in Lacustrine Ecosystems written by K. Salonen and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 292 pages. Available in PDF, EPUB and Kindle. Book excerpt: Concentrations of dissolved organic matter (DOM) in lakes are often an order of magnitude greater than concentrations of particulate organic matter; nevertheless, the biogeochemical analysis of DOM is described in only a few textbooks on limnology (most thoroughly by Wetzel). The orgins of dissolved organic substances are largely photosynthetic; DOM is either autochthonously synthesized by littoral and pelagic flora through secretions and autolysis of cellular contents, or allochthonously generated in terrestrial systems of the drainage basin, composing largely of humic substances refractory to rapid microbial degradation. The role of DOM in lacustrine ecosystems, as energy source and system regulator, however, is still poorly known. The aim of this book is: (1) to present state-of-the-art reviews of the role of dissolved autochthonous and allochthonous organic matter in pelagial and littoral zones; and (2) to focus attention on poorly understood but critical topics and hence to provide direction for future research activity.

Aquatic Organic Matter Fluorescence

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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.

Nitrogen in the Marine Environment

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Publisher : Elsevier
ISBN 13 : 1483288293
Total Pages : 919 pages
Book Rating : 4.4/5 (832 download)

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Book Synopsis Nitrogen in the Marine Environment by : Edward J. Carpenter

Download or read book Nitrogen in the Marine Environment written by Edward J. Carpenter and published by Elsevier. This book was released on 2013-10-22 with total page 919 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen in the Marine Environment provides information pertinent to the many aspects of the nitrogen cycle. This book presents the advances in ocean productivity research, with emphasis on the role of microbes in nitrogen transformations with excursions to higher trophic levels. Organized into 24 chapters, this book begins with an overview of the abundance and distribution of the various forms of nitrogen in a number of estuaries. This text then provides a comparison of the nitrogen cycling of various ecosystems within the marine environment. Other chapters consider chemical distributions and methodology as an aid to those entering the field. This book discusses as well the enzymology of the initial steps of inorganic nitrogen assimilation. The final chapter deals with the philosophy and application of modeling as an investigative method in basic research on nitrogen dynamics in coastal and open-ocean marine environments. This book is a valuable resource for plant biochemists, microbiologists, aquatic ecologists, and bacteriologists.