Optical properties of chromophoric dissolved organic matter (CDOM) in surface and pore waters adjacent to an oil well in a southern California salt marsh.
Chromophoric dissolved organic matter (CDOM) optical properties were measured in surface and pore waters as a function of depth and distance from an oil well in a southern California salt marsh. Higher fluorescence and absorbances in pore vs. surface waters suggest soil pore water is a reservoir of CDOM in the marsh. Protein-like fluorophores in pore waters at distinct depths corresponded to variations in sulfate depletion and Fe(II) concentrations from anaerobic microbial activity. These variations were supported by fluorescence indexes and are consistent with differences in optical molecular weight and aromaticity indicators. Fluorescence indices were consistent with autochthonous material of aquatic origin in surface waters, with more terrestrial, humified allochthonous material in deeper pore waters. CDOM optical properties were consistent with significantly enhanced microbial activity in regions closest to the oil well, along with a three-dimensional excitation/emission matrix fluorescence spectrum peak attributable to oil, suggesting anaerobic microbial degradation of oil.
Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA 98266, United States.
Jennifer C
JC
Bowen
Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA 98266, United States.
Catherine D
CD
Clark
Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA 98266, United States.
Jason K
JK
Keller
Schmid College of Science and Technology, Chapman University, One University Drive, Orange, CA 98266, United States. Electronic address: debruyn@chapman.edu.
Warren J
WJ
De Bruyn
D002140:California; D004784:Environmental Monitoring; D005453:Fluorescence; D061329:Oil and Gas Fields; D009930:Organic Chemicals / Q000737:chemistry*; D012965:Sodium Chloride; D013050:Spectrometry, Fluorescence / Q000379:methods; D014867:Water; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000737:chemistry*; D053833:Wetlands
D009930:Organic Chemicals; D014874:Water Pollutants, Chemical; D014867:Water; D012965:Sodium Chloride
CDOM; EEMS; Oil; Optical properties; Salt marsh