Sedimentary Concentrations of Phosphorus and Carbon: Readme file
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                   NOAA Paleoclimatology Program
                               and
            World Data Center for Paleoclimatology, Boulder
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NOTE: PLEASE CITE ORIGINAL REFERENCE WHEN USING THIS DATA!!!!!

NAME OF DATA SET: Sedimentary Concentrations of Phosphorus and Carbon
LAST UPDATE: 04/2001 (Original Receipt by WDCA Paleo)  
CONTRIBUTORS: Linda D. Anderson, M.L. Delaney, and K.L. Faul, 
University of California Santa Cruz


IGBP PAGES/WDCA CONTRIBUTION SERIES NUMBER: 2001-036

SUGGESTED DATA CITATION: Anderson, L.D., et al., 2001, 
Sedimentary Concentrations of Phosphorus and Carbon, 
IGBP PAGES/World Data Center for Paleoclimatology, Boulder
Data Contribution Series #2001-036. 
NOAA/NGDC Paleoclimatology Program, Boulder CO, USA. 

ORIGINAL REFERENCE: Anderson, L.D., M.L. Delaney, and K.L. Faul, 2001,
Carbon to phosphorus ratios in sediments:  Implications for nutrient cycling, 
Global Biogeochemical Cycles, vol. 15(1), P. 65- 79.

GEOGRAPHIC REGION: Global
PERIOD OF RECORD: 0-70 MMYrBP

LIST OF FILES: Readme_Anderson2001.txt (this file), 
Appendix.doc (Microsoft Word format), 
Appendix.txt (tab-delimited ASCII text).


DESCRIPTION:
Sedimentary Concentrations of Phosphorus and Carbon.

Abstract
Defining the transformations of phosphorus (P) in sediments is critical 
to assessing the geochemical behavior of sedimentary P and the behavior 
of reactive P (Preactive = Poxide-associated + Pauthigenic + Porganic). 
relative to organic carbon (Corganic).  This study includes the 
determination of P components and Corganic concentrations on samples 
from sites in the California Current region (Ocean Drilling Program 
[ODP] leg 167, sites 1010, 1011, 1012, 1014, 1016, and 1021), 
in the Benguela Current region (ODP leg 175, sites 1082, 1084, and 1085), 
and on Blake Nose in the western Atlantic (ODP leg 171B, sites 1050 and 1052).  
Sample depths range from 0.45 m to 650 m and ages up to 65 Ma.  
Our data demonstrate the transformation of labile forms of P 
(Porganic and Poxide-associated) to Pauthigenic throughout the sediment 
column in all redox states and at all sedimentation rates investigated, 
until a substantial portion of reactive P is in the authigenic form (>80%).  
(C/P)organic ratios are always greater than or equal to the Redfield Ratio 
in all of the sediments that we studied.  Sediments with Corganic 
concentrations less than or equal to 2 wt% have Corganic/Preactive ratios 
less than the Redfield Ratio, and Corganic/Preactive ratios increase linearly 
with Corganic, consistent with degradation of Corganic with age.  In general, 
Corganic/Preactive ratios for sediments with Corganic concentrations 
greater than or equal to 2 wt%, from a variety of redox states and 
sedimentation rates, center around the Redfield Ratio, although some ratios 
are as high as 3x the Redfield Ratio.  However, Corganic/Preactive ratios 
(up to 400) do not approach the high ratios observed for (C/P)organic ratios 
(up to 4500).  Because of the efficient transfer of labile forms of P to 
Pauthigenic, Corganic/Preactive ratios better describe the geochemical 
behavior of sedimentary P.