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Dr. Laodong Guo Professor School of Freshwater Sciences (SFS) |
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Current Research Projects
• MRI: Acquisition of a flow field-flow
fractionation system to enhance colloidal research and education at USM. Funded by National
Science Foundation (NSF)-Major Research Instrument (MRI) program
(NSF-MRI #1126420) through OCE
Division of Ocean Sciences. $161,910 with additional 30% matching funds from the university, funding
period: January 2012-December 2013, (Principal Investigator with Co-PIs: Drs.
Orcutt and Shiller).
We propose to acquire an asymmetric flow
field-flow fractionation (FFF) system. This instrument will support
cross-disciplinary faculty research that integrates graduate and undergraduate
education with research. The requested instrument will add new research
capabilities, support and augment graduate education and ongoing research
projects in natural colloids and nanoparticles in aquatic systems. It has been
shown that colloids and nanoparticles are important intermediaries in
regulating the concentration and speciation and thus the fate, transport and
bioavailability/toxicity of many chemical species and contaminants in aquatic
environments. However, quantitative characterization of natural colloids and
knowledge of their environmental behavior remains scarce. Flow field-flow
fractionation is a chromatograph-like elution technique capable of simultaneous
separation and characterization of colloids, nanoparticles and macromolecules.
It has the advantages of providing a continuous size distribution or size
spectrum of colloids and other nanoparticles. By interfacing directly or
indirectly with other online or offline detection techniques such as ICP-MS and
gamma/alpha spectrometer, it will allow the elucidation of pathways and
mechanisms in the interactions between colloids/macromolecules and trace metals
and radionuclides in aquatic environments.
• Gulf of Mexico Research Initiatives
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RAPID: Effect of oil
spill on organic carbon partitioning and transformation in the water column in
the northern Gulf. (NSF-OCE
#1042790), $60,000, funding period: 06/01/2010-05/31/2012 (no-cost
extension), principal investigator.
This is a Rapid Response Research
(RAPID) project funded by National Science Foundation
(NSF) Chemical
Oceanography Program (NSF-OCE#1042790).
We will examine the Deepwater Horizon oil spill in the northern Gulf of Mexico -- an oil spill of national significance
-- to study the fate, transport and transformation of crude oil components and
their interactions with marine organic matter from baseline to maximum impact
in a complete time series. Their working hypothesis is that the crude oil
components are isotopically light (in terms of carbon-13) and distinct in
optical properties (UV-vis and fluorescence) from natural marine organic matter,
thus allowing the use of stable isotopes and fluorescence techniques for
quantitative understanding of their fate, transport, and transformations in the
northern Gulf of Mexico. They will collect seawater samples at a station in the
Mississippi Bight in the northern Gulf of Mexico
from base line conditions to maximum impact. EEM fluorescence, stable isotopes,
and flow field-flow fractionation techniques will be employed. Results of this
study are expected to provide new insights into how organic matter from oil
spills interacts with marine organic matter affecting the ocean carbon budget,
biogeochemical processes, and marine ecosystems as a whole.
•
RAPID: Responses of Benthic
Communities and Sedimentary Dynamics to Hydrocarbon Exposure in Coastal Ecosystems
of the northern Gulf of Mexico . (NSF-OCE#1042907),
$147,874, June
2010-May 2011, (no-cost
extension), Co-PI with Drs.Yeager, Brunner, and Briggs.
This is a
RAPID award to respond to the Deep Horizon oil spill in the Gulf
of Mexico . The work involves the time series collection of samples
to examine the changes, from baseline conditions to maximum exposure, to the
oil leaking out of the deepwater well head to a variety of coastal sites along
the Northern Gulf of Mexico . Sampling sites
include the intertidal zone at Belle Fontaine Point in eastern Mississippi and the New
Harbor Islands
in Louisiana
• 2010-2012:Time-series and Underway Assessments
of Ocean Acidification and Carbon System Properties in Coastal Waters
(supported by NOAA through Northern Gulf Institute). This project will provide time-series
observations of coastal ocean pH and carbon system properties in various
coastal regions in support of NOAA goals. While the majority of the work will
focus on the Gulf of Mexico, additional time-series sites will be maintained in
the South Atlantic Bight and
•
Examining
the binding of radionuclides with marine biopolymers, A comparative study on
Th, Pa, Be, Po and Pb isotopes. (NSF-OCE#0850957), principal
investigator, funding period: 2009-2012.
Funded by National Science Foundation (NSF) Chemical
Oceanography Program (NSF-OCE#0850957).
Th(IV), Pa(IV,V), Po(IV, II,-II), Pb(II)
and Be(II) radioisotopes are important proxies in oceanographic investigations,
such as, for tracing particle dynamics and particulate organic matter (POC)
fluxes out of the euphotic zone, and for studying boundary scavenging,
paleo-productivity and ocean circulation. Even though considered routine, these
approaches rely on often poorly constrained, empirically determined and
variable isotope ratios or ratios to POC. Previously conducted laboratory and
field investigations suggest that a number of biopolymers, potentially produced
by both phytoplankton and bacteria, are carrier molecules for most of these
isotopes, rather than purely inorganic surfaces. Our hypothesis is that
specific binding and redox processes control marine scavenging and the most efficient
binding would occur to acid polysaccharide- and protein-containing
biomolecules. Proposed experiments will attempt to separate, identify and
characterize radioisotope carriers that are hypothesized to be effective
binding ligands. Our proposed interdisciplinary research project will require
instrumental approaches for characterization studies, in combination with
controlled laboratory and field experimentation. Laboratory studies consist of
comparative uptake experiments of a suite of naturally occurring radionuclides
to a number of substrates, including model organic and inorganic compounds,
marine colloidal and particulate organic matter, and biopolymers harvested from
cultures. The proposed field program will include collections and characterization
of diverse types of suspended and sinking organic matter from different parts
of the ocean.
• Coastal Impact Assistance Project (CIAP):
What is the state of health of the
Recent Research Projects
• MRI-RAPID: Acquisition of Spectroscopic
Instrumentation for Oil Spill Research (NSF-MRI
#1057726), $108,871, funding period: 8/1/2010-7/31/2011, (Co-PI with Dr. Shiller).
Through
this NSF MRI-RAPID grant
and matching funds from University of Southern Mississippi (USM), we obtained several items of equipment to
be used to determine machine, water isotopes and colored dissolved organic
matter (CDOM) in oil spill samples in the Gulf of Mexico .
The requested instrumentation includes two cavity ring down spectrometers
(CRDS), one for determination of methane and the other for determination of the
oxygen and hydrogen isotopic composition of water. The CRDS methane analyzer is
needed because a significant fraction of material discharged from the Macondo
well is methane. The CRDS water isotope analyzer will allow the PI's to utilize
oxygen and hydrogen isotopes of water as a coastal water mass tracer. Both CRDS
instruments are robust enough to be used in the field. Using them in the field
will allow the PI's to adjust their sampling strategies based on the analytical
information obtained and to better understand water circulation/mixing and thus
oil transport and transformation in the northern Gulf of
Mexico . In addition, the PI's request a UV/visible
spectrophotometer. The spectrophotometer is a basic tool needed for determining
the optical properties of natural organic matter and oil-contaminated waters to
quantify the fate, transport and transformation of oil components.
• Monitoring
and Assessment of Coastal and Marine Ecosystems in the Northern Gulf”
(NGI/NOAA). This project is aimed at understanding the coastal nutrient,
carbon, and trace element fluxes in these several key environments, with an
emphasis on better understanding the transport and processing of nutrients and
pollutants through the coastal transition zone. A key element to this is the
role of fluvial inputs. Freshwater riverine input and it's associated dissolved
and particulate matter have a myriad of positive and negative effects on
coastal ecosystems. Basic steps in understanding the effects of inputs from
rivers and estuaries on coastal ecosystems include measuring the variability of
flow rates and concentrations of the constituents, tracking the concentrations
offshore from the input regions and determining the effects of freshwater input
to development of stratification and water quality variations. Time series of
these basic observations will be used to further understanding about the
processes transforming riverine input within the ecosystem of the northern
•
• Spatial
variation and temporal trend of water quality in the northern Gulf of Mexico,
This is a research project supported by the National Oceanographic and
Atmospheric Administration (NOAA) through
the Northern
Gulf of Mexico (NGI), a NOAA Cooperative Institute. We proposed to conduct
ground truth observations and standardize algorithms to produce and evaluate
the spatial and temporal variations of water quality parameters (concentrations
of suspended organic (SOM) and inorganic matters (SIM), and water clarity) in
the Northern Gulf of Mexico, an effort aimed at improving the monitoring of
NGOM ecosystem based on remote sensing and understanding the dynamics of harmful
algae blooms in the northern Gulf of Mexico (Co-PI with Dr. Zhong-Ping Lee at Mississippi State University).
September 2009-September 2011.
• Composition and Fluxes of Organic
Carbon Species from the Yukon
River Basin
Funded by National Science
Foundation (NSF) Integrated Carbon Cycle Research Program (2004-2009, Principal Investigator).
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This project seeks to understand the biogeochemical
processes governing the composition, reactivity, transformation and flux of
organic carbon species, including dissolved, colloidal and particulate organic
carbon from the To learn more about global carbon cycle, click here. See also IARC research highlights. |
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Major publications from this project: 1. Belzile,
C. and Guo, L. 2006. Optical properties
of low molecular weight and colloidal organic matter: Application of the
ultrafiltration permeation model to DOM absorption and fluorescence. Marine Chemistry, 98, 183-196. 2. Gueguen,
C., Guo, L., Wang, D. Tanaka, N, and Hung, C.-C. 2006. Chemical
characteristics and origin of dissolved organic matter in the 3.
Guo, L., and Macdonald, R.W. 2006. Source and
transport of terrigenous organic matter in the upper 4. Zou,
L., Sun, M.-Y. and Guo, L. 2006. Temporal variations of organic carbon
inputs into the upper 5. Guo, L. and Santschi, P.H. 2007. Ultrafiltration and its applications to sampling and characterization of aquatic colloids. In "Environmental Colloids and Particles," Wilkinson, K. and Lead, J. (Eds), Chapter 4, p159-221, International Union of Pure and Applied Chemistry (IUPAC) Series on Analytical and Physical Chemistry of Environmental Systems, John Wiley. 6.
Guo, L.D., 7. Elmquist,
M., Semiletov, 8.
Cai, Y., Guo, L.D. and 9.
Cai, Y., Guo, L., 10. Xu,
C.H., Guo, L., Dou, F. and 11. Xu,
C.H., Guo, L., Ping, C. L., and White, D. M. Chemical and isotopic characterization of size-fractionated organic matter
from cryoturbated soils, 12. Cai, Y. and Guo, L. 2009. Abundance and
variation of colloidal organic phosphorus in riverine, estuarine and coastal
waters in the northern 13. McGuire, A.D., 14. Cooke,
M.P., van Dongen, B. E., Talbot, H.M., Semiletov, 15. Guo, L., Cai, Y., Belzile, C. and Macdonald, R. 2010. Sources and export
fluxes of inorganic and organic carbon and nutrient species from the
seasonally ice-covered |
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1151-1159,
• Collaborative Research: Th(IV) and Pa(IV, V)
binding to exopolymeric acid and polysaccharides in marine environments (NSF-OCE#0350758 or OCE#0627820,
2004-2009)
Funded by the National
Science Foundation (NSF) Chemical
Oceanography Program (2004-2009).
Th(IV) and Pa(IV,V) isotopes are important
proxies in oceanographic investigations, such as, for tracing particle dynamics
and particulate organic matter (POC) fluxes out of the euphotic zone through the
use of 234Th/POC ratios, and for studying boundary scavenging,
paleoproductivity and ocean circulation through the use of 231Pa/230Th ratios.
Even though almost routine, these approaches rely on often poorly constrained,
empirically determined and variable isotope ratios or ratios to POC. Previously
conducted laboratory and field investigations suggest that Th(IV) removal could
be controlled through binding by exopolymeric acid polysaccharide (APS) rich
biomolecules, potentially produced by both phytoplankton and bacteria. However,
we believe that Pa(V) present in ocean water must first be reduced to Pa(IV) by
organic biomolecules before efficient binding to solid phases can occur, and
that the most efficient binding would occur to APS-rich biomolecules produced
by phytoplankton species such as diatoms, prymnesiophytes and cyanobacteria. In
this study, the team of scientists at Texas A&M Research Foundation and the
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Partitioning of Th-234 among dissolved, colloidal and particulate
phases in seawater |
Fractionation between Th(IV) and
Pa(IV,V) scavenging in the ocean resulting from particulate composition
difference (from Guo et al. 2002) |
Dr. Yihua Cai sampling during a 2006 cruise to the |
The R/V Seward
Johnson |
Publications from this NSF project
- Benitez-Nelson
C. and Th-234 Group. 2004. Future applications of Thorium-234 in aquatic
ecosystems. EOS, Transactions,
American Geophysical
- Hung,
C.C., Guo, L., Roberts, K.A. and Santschi, P.H. 2004. Upper ocean
carbon fluxes determined by the 234Th approach and sediment
traps using size fractionated POC and 234Th data from the
- Buesseler, K. O., Benitez-Nelson, C., Moran, S. B., Burd, A. , Charette, M. , Cochran, J. K., Coppola, L., Fisher, N., Fowler, S. W., Gardner, W., Guo, L. D., Gustafsson, O., Lamborg, C., Masque, P. , Miquel, J. C. , Passow, U., Santschi, P.H., Savoye, N., Stewart, G., and Trull, T..2006. An assessment of particulate organic carbon to thorium-234 ratios in the ocean and their impact on the application of 234Th as a POC flux proxy. Marine Chemistry, 100, 213-233.
- Santschi,
P.H.,
- Wang,
D., Henrichs, S.M. and Guo, L. 2006. Distributions of nutrients,
dissolved organic carbon and carbohydrates in the western
- Guo, L. and Santschi, P.H. 2007. Ultrafiltration and its applications to sampling and characterization of aquatic colloids. In "Environmental Colloids and Particles," Wilkinson, K. and Lead, J. (Eds), Chapter 4, p159-221, International Union of Pure and Applied Chemistry (IUPAC) Series on Analytical and Physical Chemistry of Environmental Systems, John Wiley.
- Guo, L.D., Warnken, K.W. and Santschi, P.H. 2007. Retention behavior of dissolved uranium during ultrafiltration, implications for colloidal U in surface waters. Marine Chemistry, 107(2), 156-166.
- Hung, C.-C., Moran, S. B., Cochran, J. K.,
Guo, L.D., and Santschi. P.H. 2008. Comment on: How accurate are 234Th
measurements in seawater based on the MnO2-impregnated
cartridge technique? by Pinghe Cai et al.” Geochemistry Geophysics Geosystems, 9, Q02009, doi10.1029/2007GC001770.
- Zou, L., Guo, L.D., Sun, B.W. and Sun, M.Y. 2008, Origins of high-molecular-weight dissolved organic matter in the Middle Atlantic Bight: Clue from lipids and molecular d13C ratio. The Open Oceanography Journal, 2, 1-5.
- Guo, L. and M.-Y. Sun. 2009. Isotope composition of organic matter in seawater. In: "Practical Guidelines for the Analysis of Seawater", O. Wurl, editor, Chapter 6, p97-123, CRC Press-Taylor and Francis Group, LLC.
- Guo,
L., White, D.M., Xu, C., and Santschi, P.H. 2009. Chemical and
isotopic composition of HMW-DOM from the
- Zhou, Z., Stolpe, B. and Guo, L. 2009.
Composition and size spectra of colored dissolved organic matter in river
waters as characterized by fluorescence EEM and flow field-flow
fractionation techniques. The 2009
- Stolpe, B., Guo, L. Shiller, A. and Hassellov,
M. 2010. Size and composition of colloidal organic matter and Fe in the
- Wang,
X., Cai, Y. and Guo, L.
2010. Preferential removal of dissolved carbohydrates during estuarine
mixing in the
doi:10.1016/j.marchem.2010.01.006
(see Abstract
on line or pdf). - Hung, C.-C.,
Xu, C., Santschi, P. H., Zhang, S., Schwehr, K.A., Quigg, A., Guo, L.,
Gong, G.-C., Pinckney, J., Long, R., and Wei, C.-L. 2010. Comparative evaluation of sediment-trap
and 234Th-derived POC fluxes from the upper oligotrophic waters
in the Gulf of Mexico and the subtropical northwestern doi:10.1016/j.marchem.2010.03.011.
• Flux and transformation of organic carbon across the
eroding coastline of northern
Funded by the National Science Foundation (NSF) Arctic
System Science/Office of Polar Program
(2005-2009),
through collaboration with Drs. Chien-Lu
Ping and
Yuri Shur at UAF and Torre Jorgenson at ABR
Inc., Fairbanks (meet these
PIs). Our project is part of SNACS (Study of the
Northern Alaska Coastal System) Program, a contribution to the study of
environmental arctic change (SEARCH).
This proposed research addresses
scientific questions through four main components designed to: (1) characterize
the abundance, composition, and age of soil OC and the abundance and structure
of ground ice in relation to geomorphic environments, (2) estimate the total OC
flux along the entire Alaskan Beaufort Sea coast and develop empirical models
based on terrain and oceanographic factors to assess the vulnerability of the
coasts to increased erosion resulting from a longer fetch due to sea-ice
retreat, (3) to determine the biogeochemical transformation and bioavailability
of OC associated with various dissolved and particulate forms as they cross the
land/sea interface through field study and controlled laboratory
experimentation; and (4) integrate our results to the pan-arctic scale through
international collaboration with the Arctic Coastal Dynamics program. The study
will involve extensive sampling at 50 random locations along the entire coast
to develop precise estimates of OC abundance and flux with explicit confidence
limits. Intensive sampling at three key sites that represent the dominant
coastline types will be conducted to evaluate the transformation of the eroded
OC. Three additional secondary sites will be established to broaden the
monitoring to other coastline types and to involve local communities in the
assessment of coastal changes.
Broader Impacts: This project will provide information
critical to understanding of biogeochemical consequences of environmental
changes in the northern
Publications from this NSF project (Guo’s Group)
• Guo,
L.D.,
• Dou,
F.,
• Elmquist, M., Semiletov,
• Xu,
C.H., Guo, L., Dou, F. and
• Xu,
C.H., Guo, L.,
•
Cooke, M.P., van Dongen, B. E., Talbot, H.M., Semiletov, 
1151-1159,
doi:10.1016/j.orggeochem.2009.07.014,
(abstract or
pdf)
• Dou, F., Yu, X.,
• Zhang,
J.-Z., Guo, L. and Fischer,
C.R. 2010. Abundance and Chemical Speciation of Phosphorus in Sediments of the
Mackenzie Delta,
•
• Ping,
C.-L., G.J. Michaelson, L.D. Guo, M.T. Jorgenson, M. Kanevskiy, Y. Shur, F. Dou
and J. Liang. 2011. Soil carbon and material flux across the eroding coastline
of the Beaufort Sea,
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Export of old terrigenous organic matter across the arctic land/ocean interface: Evidence from estuarine sedimentary organic carbon 14C ages along the Siberian Arctic coast (from Guo et al., 2004, Global Biogeochemical Cycles, 18(1), GB1036, pdf file). |
Increasing coastal erotion under a changing climate in the North What are the impacts and biogeochemical consequencies of climate and environmental change in the north? |
A NSF Supported project (NSF-OCE #9906823): Th-234 has been widely used as a tracer to quantify the
fluxes of organic carbon export from the euphotic zone to the deep ocean in
many global research projects, such as Joint
Global Ocean Flux Study (JGOFS). Particulate organic carbon (POC)
fluxes are calculated as the product of the 234Th export flux times the
POC/234Th ratio. However, POC/234Th ratio in suspended and sinking particles
are not constant. It varies with different particle sizes, water depths, and
study areas. Understanding factors controlling the POC/234Th ratio in the ocean
is of paramount importance in global carbon cycle study and thus the climate
changes in the time scale of human concern.
The major objectives of the
proposed work are: 1) To collect colloidal, suspended and sinking particles
from marine environments for laboratory studies and to quantify the
relationships between the abundance of polysaccharide enriched marine
aggregates and Th(IV) deficiency (See photos of R/V Gyre 2000
and 2001Cruises); 2) To
conduct controlled laboratory experiments to investigate the interactions of Th
(IV) with individual organic compound classes of marine organic matter to
elucidate whether complexing of Th is a non-selective physicochemical process
(less likely) or organic ligand dependent (most likely); 3) To characterize the
bulk chemical, surface chemical, and isotopic composition of marine organic
matter to determine their acid-base and ligand properties and the nature of
organic or inorganic functional groups that Th (IV) tracks; 4) To construct an
improved scavenging model which relies on information on Th(IV) sorption to
strong surface active and non-surface active ligand groups in particulate and
colloidal organic matter. Experimental and model results will be used to
recommend improvements in the use of POC/234Thp ratios for POC flux
determinations.
• Role of natural organic matter in governing the bioavailability
of potentially toxic metals to estuarine bivalves (SeaGrant/NOAA, 2001-2004)
Supported by NOAA-Sea Grant: Bivalves have been extensively used as bio-indicator
organisms in environmental assessment and monitoring programs to assess the
bioavailable contaminant concentrations in coastal environments (e.g., NOAA's
NS&T program). Natural dissolved organic matter (DOM) is ubiquitous and is
a potentially nutritious food source for bivalves. However, the presence of DOM
may significantly alter the bioavailability and biogeochemical cycling pathways
of many trace metals in marine environments. The role of natural DOM in
governing the bioavailability of potentially toxic metals to bivalves is not
well understood and has rarely been tested. To better use bivalves as pollution
indicator organisms, a thorough understanding of metal uptake pathways and
mechanisms as a function of the quality and quantity of DOM is sorely needed.
The primary objectives of this research is to determine how DOM affects the
bioavailability of metals to bivalves, including oysters (Crasostrea
virginica) and mussels (Ischadium recurvum), and whether DOM can be
directly used as a food source by these bivalves using radiotracers and
molecular probes in controlled laboratory experiments. Our research will provide
crucial information applicable to environmental assessment and monitoring.
This is a research project supported by the NOAA-Sea Grant between
2001-2004, collaborating with Professor Peter Santschi
and Professor Sammy Ray in the
Laboratory for Oceanographic and Environmental Research (LOER) at the Texas A&M University at Galveston. My previous SeaGrant
supported project, namely "Bioavailability
of colloid-associated metals to estuarine bivalves" was completed during
1998-2001.
Ssee our publications in Environmental Science and
Technology (Guo et al. 2001, pdf)
and Marine
Environmental Research (Guo et al., 2002, pdf).
• Nature and fluxes of nutrients and organic matter from Yukon
River Basin (IARC, 2001-2004)
Principal investigator, Supported by Japan Frontier Research System for Global
Change/IARC: The Yukon River is one
of the largest rivers draining into the Arctic with an annual discharge of more
than 200 billion m3 of freshwater and ~60 million tons of suspended sediment,
and contributes ~8% of the total freshwater input to the Arctic Ocean.
Recent evidence shows that the polar region and the northern ecosystem are
quite sensitive to global and regional climate and environmental changes.
Therefore, environmental and climate changes in the northern arctic and thus increasing
freshwater flow and organic matter inputs from the Yukon River Basin will have
profound impacts on the ecosystem and biogeochemical cycles in the Bering Sea
and Arctic Ocean. However, due to its remoteness and the extreme weather
conditions, the
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• Radiocarbon and molecular characterization of organic compound
classes of dissolved organic matter in the ocean
Dissolved organic carbon (DOC) is the largest
organic C pool in the ocean and plays an important role in the global carbon
cycling. However, understanding the cycling of DOC in the ocean remains a major
challenge to oceanographers despite recent advances in marine organic carbon
cycling. To further explore the detailed biogeochemical pathways of different
organic components and to better understand the complex cycling of DOC in the
ocean, measurements of isotopic composition in different organic compound
classes are sorely needed, as are the chemical and molecular characterization
of different size or molecular weight fractionated DOC components.
The major objectives of the proposed research are: 1) To collect large
quantities of high molecular weight (HMW) dissolved organic matter from
seawater for chemical and isotopic characterizations, using cross-flow
ultrafiltration techniques; 2) To characterize elemental composition, major
organic compound classes and individual organic molecules using elemental
analysis, pyrolysis-GC/MS and liquid extraction techniques; 3) To determine
radiocarbon (14C) and stable carbon (d13C) and nitrogen (d15N) isotope
signatures of major organic compound classes, amino acids,
carbohydrates, total lipids, and acid-insoluble fractions in isolated HMW DOC
fractions; 4) To elucidate how chemical composition and isotope signatures of
the compound classes reflect their production and decomposition processes in
the ocean and to better understand the biogeochemical pathways and turnover
times of each compound class, whose geochemical behavior could be significantly
different from that of the total DOC pool.
This is a collaborative proposal declined by the National
Science Foundation (NSF) - Ocean
Science Division.
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A schematic diagram of a ultrafiltration system for isolating colloids and naoparticles from natural waters (from Guo 1995). |
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Research collaborators
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Name |
Department |
Affiliation |
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Oceanography and Marine Sciences |
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Laboratory for Isotope Geology |
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Department of Oceanography |
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Department of Oceanography |
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Pacific Oceanological Institute |
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Dr. Xiaoling Ding |
Environmental Sciences |
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Soil
Sciences |
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Dr. Chin-Chang Hung |
Oceanography |
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Dr. Robie Macdonald |
Marine Environmental Quality |
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Water Chemistry, GEES |
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Dr. Tom Douglas |
CRREL, |
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Dr. Ming-Yi SUN |
Major Equipment
Total organic carbon and nitrogen
analyzer (Shimadzu TOC-V) with
capability of measuring DOC and TN;
Canberra
gamma counting system, with ultrahigh purity Ge well detector and multichannel
analyzer;
Shimadzu RF-5301 Spectroflurometer;
Aglient 8453
Spectrophotometer;
TIDAS-LWCC High Performance fiber
optic spectrophotometer (World Precision Instruments)
Autoanalyzer (Seal) for nutrient analysis;
Flow field-flow fractionation
(FlFFF) and SPLITT systems (Postnova
Analytics) which can be
coupled with on-line detectors such as UV absorbance, fluoresce, refractive
index, light scattering. and ICP-MS, providing continuum size spectra in
colloidal and nanoparticle materials in natural waters.
Cross-flow ultrafiltration
systems (e.g., Millipore Proflux
M-30 and Amicon DC-10 systems);
Ultra-pure water system,
ultracentrifuge, freeze dryer, clean benches, auto balances, etc.
See also Center for Trace Analysis at USM
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This page Copyright © 2001-2011 Laodong
Guo.
Last updated Wednesday, June 01, 2011