Download or read book Characterization of Biologically Produced Colored Dissolved Organic Matter written by and published by . This book was released on 1999 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Colored dissolved organic matter (CDOM) is one of the principal light-attenuating components of seawater. Over the past decade considerable progress has been made in describing the optical properties of CDOM. However, our understanding of CDOM structure and chemistry has not advanced apace, and we do not yet understand many of the factors that introduce and remove CDOM in seawater. Our objectives are to chemically characterize CDOM and to develop techniques for studying CDOM cycling in seawater. Recent work suggests that a large fraction of marine DOM consists of complex carbohydrates and proteins that are produced directly from biosynthesis, yet are biologically refractory towards microbial degradation. Previous studies have also suggested that a large fraction of CDOM is associated with biological activity. We wish to determine if marine phytoplankton and bacteria produce significant quantities of CDOM, and to compare the chemical characteristics of biologically produced CDOM with CDOM in seawater.
Download or read book Characterization of Biologically Produced Colored Dissolved Organic Matter in Seawater written by and published by . This book was released on 2005 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chromophoric, or colored dissolved organic maller (CDOM), influences the structure of aquatic ecosystems, complicates satellite measurements of ocean productivity, and affects the bioavailability and fate of important trace organic and metal species in seawater. The goals of this project were to chemically characterize biologically produced CDOM components, to characterize CDOM in laboratory algal cultures, and to develop techniques for studying CDOM cycling in seawater. Specifically, we compared the chemical characteristics of freshwater and marine CDOM in the Mississippi River estuary and Gulf of Mexico, characterized CDOM at two open ocean sites (N. Pacific Ocean, Sargasso Sea) and compared CDOM components with CDOM produced by laboratory cultures of marine algae. CDOM was collected by adsorption onto C18 resin from acidified seawater. From this fraction we identified 2,4-dichlorobenzoic acid (2,4-DCBA) and a series of tetrachloro-biphenyl aromatic acids (TCBCAs) that are structurally related to POBs as major components. Structures were determined using proton NMR, gas chromatographylmass spectrometry, and HPLC analyses by co-injection with authentic compounds. High concentrations of chlorinated aromatic acids were found in all seawater samples, but were not found in samples of Mississippi River water. The biological production of 2,4-DCBA and TCBCAs was confirmed by their production in laboratory cultures of the marine algae Emlliana huxleyi and Isochrysis galbana. Spent culture media from these two algae contained up to 500 mug/L 2,4-DCBA and 12 mug/L TCBCAs.
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
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.
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.
Download or read book Dynamics and Characterization of Marine Organic Matter written by T. Hama and published by Taylor & Francis US. This book was released on 2000 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade the scientific activities of the Joint Global Ocean Flux Study (JGOFS), which focuses on the role of the oceans in controlling climate change via the transport and storage of greenhouse gases and organic matter, have led to an increased interest in the study of the biogeochemistry of organic matter. There is also a growing interest in global climate fluctuations. This, and the need for a precise assessment of the dynamics of carbon and other bio-elements, has led to a demand for an improved understanding of biogeochemical processes and the chemical characteristics of both particulate and dissolved organic matter in the ocean. A large amount of proxy data has been published describing the changes of the oceanic environment, but qualitative and quantitative estimates of the vertical flux of (proxy) organic compounds have not been well documented. There is thus an urgent need to pursue this line of study and, to this end, this book starts with several papers dealing with the primary production of organic matter in the upper ocean. Thereafter, the book goes on to follow the flux and characterization of particulate organic matter, discussed in relation to the primary production in the euphotic zone and resuspension in the deep waters, including the vertical flux of proxy organic compounds. It goes on to explain the decomposition and transformation of organic matter in the ocean environment due to photochemical and biological agents, and the reactivity of bulk and specific organic compounds, including the air-sea interaction of biogenic gases. The 22 papers in the book reflect the interests of JGOFS and will thus serve as a valuable reference source for future biogeochemical investigations of both bio-elements and organic matter in seawater, clarifying the role of the ocean in global climate change.
Download or read book The Isolation and Partial Characterization of the Dissolved Organic Matter in Seawater written by Richard A. Kerr and published by . This book was released on 1977 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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.
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.
Download or read book Spectroscopic Characterization of Dissolved Organic Matter written by Xiaoyan Cao and published by . This book was released on 2014 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization and Optical Properties of Colored Dissolved Organic Matter During the Coastal Mixing Optics Experiment Using in Situ and Discrete Sampling Methods written by Robyn Nicole Conmy and published by . This book was released on 1999 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Spectroscopic Characterization of Dissolved Organic Matter written by John Robert Helms and published by . This book was released on 2012 with total page 438 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fluorescence and Size Characterization of Dissolved Organic Matter in Riverine and Sea Waters in the Northern Gulf of Mexico written by Zhengzhen Zhou and published by . This book was released on 2012 with total page 406 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Molecular Characterization of Dissolved Organic Matter DOM in Seawater written by Jasper Daniel Hendrik van Heemst and published by . This book was released on 2000 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Molecular Characterization and Photochemical Transformation of Dissolved Organic Matter from Land to Ocean written by Hongmei Chen and published by . This book was released on 2014 with total page 344 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Isolation and Physiochemical Characterization of Dissolved Organic Matter Across Limnic and Oceanic Systems written by Shamus J. Driver and published by . This book was released on 2020 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of the Hydrophobic Fraction of Marine Dissolved Organic Matter by High Performance Liquid Chrromatography written by Richard Michael Swaine and published by . This book was released on 1996 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt:
