@article {402,
	title = {Inputs of Fossil Carbon from Wastewater Treatment Plants to US Rivers and Oceans},
	journal = {Environmental Science \& Technology},
	volume = {43},
	year = {2009},
	note = {id: 1833; 476XR Times Cited:0 Cited References Count:51Y},
	pages = {5647-5651},
	abstract = {Every day more than 500 million cubic meters of treated wastewater are discharged into rivers, estuaries, and oceans, an amount slightly less than the average flow of the Danube River. Typically, wastewaters have high organic carbon [OC) concentrations and represent a large fraction of total river flow and a higher fraction of river OC in densely populated watersheds. Here, we report the first direct measurements of radiocarbon (C-14) in municipal wastewater treatment plant (WWTP) effluent. The radiocarbon ages of particulate and dissolved organic carbon (POC and DOC) in effluent are old and relatively uniform across a range of WWTPs in New York and Connecticut. Wastewater DOC has a mean radiocarbon age of 1630 +/- 500 years B.P. and a mean delta C-13 of -26.0 +/- 1 parts per thousand. Mass balance calculations indicate that 25\% of wastewater DOC is fossil carbon, which is likely derived from petroleum-based household products such as detergents and pharmaceuticals. These findings warrant reevaluation of the "apparent age" of riverine DOC, the total flux of petroleum carbon to U.S. oceans, and OC source assignments in waters impacted by sewage.},
	issn = {0013-936X},
	doi = {10.1021/As9004043},
	author = {Griffith, D. R. and Barnes, R. T. and Raymond, P. A.}
}
@article {1888,
	title = {Carbon export and cycling by the York, Tanana and Porcupine Rivers, Alaska, 2001-2005},
	journal = {Water Resources Res.},
	volume = {43},
	year = {2007},
	note = {id: 1162},
	month = {2007},
	author = {Striegl, R. G. and Dornblaser, M. M. and Aiken, G. R. and Wickland, K. P. and Raymond, P. A.}
}
@article {2443,
	title = {Linking lithology and land use to sources of dissolved and particulate organic matter in headwaters of a temperate, passive-margin river system},
	journal = {Geochimica Et Cosmochimica Acta},
	volume = {71},
	year = {2007},
	note = {30},
	month = {Sep},
	pages = {4233-4250},
	abstract = {A number of rivers have been found to transport highly aged organic matter [OM]; however, the sources of this aged material remain a matter of debate. One potential source may be erosion and weathering of headwater lithologies rich in ancient sedimentary OM. In this study, waters, suspended particulates, streambed sediments, rocks and soils from fourteen small headwater watersheds of a mid-size, temperate, passive margin river were sampled and characterized by Delta C-14, delta C-13, and POC/TPN ratios to identify sources of particulate and dissolved OM delivered to the river mainstem. These headwater sites encompass a range in lithology (OM-rich shales, OM-lean carbonate/mudstone facies, and OM-free crystalline rocks) and land use types (forested and agricultural), and allow investigation of the influence of agriculture and bedrock types on stream OM characteristics. Streams draining large areas of both agricultural land use and OM-rich lithology contain particulate OM [POM] that is more C-14-depleted than streams draining forested, shale-free watersheds. However, this is not sufficient to account for the significantly lower Delta C-14-POC measured in the river mainstern. Dissolved OM [DOM] Delta C-14 are in all cases enriched compared to POM from the same stream, but are otherwise highly variable and unrelated to either land use or lithology. POC/TPN ratios were likewise highly variable. POC and DOC delta C-13 signatures were similar across all watersheds. Based on isotope mass balance, C-14-free fossil OM sources contribute 0-12\% of total stream POM. Although these results do not unequivocally separate the influences of land use and lithology, watershed coverage by shale and agriculture are both important controls on stream A Delta C-14-POC. Thus export of aged, particle-associated OM may be a feature of river systems along both passive and active continental margins. (C) 2007 Elsevier Ltd. All rights reserved.},
	keywords = {ATCHAFALAYA RIVER, ATMOSPHERIC O-2, BLACK SHALE, continental-shelf, GULF-OF-MEXICO, marine-sediments, MINERAL, SPACE-TIME CLIMATE, STABLE-ISOTOPES, surface sediments, SURFACES},
	isbn = {0016-7037},
	doi = {10.1016/j.gca.2007.06.056},
	author = {Longworth, B. E. and Petsch, S. T. and Raymond, P. A. and Bauer, J. E.}
}
@article {977,
	title = {Quantity, C-14 age and lability of desorbed soil organic carbon in fresh water and seawater},
	journal = {Organic Geochemistry},
	volume = {38},
	year = {2007},
	note = {id: 1161},
	pages = {1547-1557},
	abstract = {Soil organic carbon (OC) resulting from terrestrial photosynthesis is one of the largest reactive pools of sequestered atmospheric CO2. As an intermediate storage mechanism for organic material through time, the vertical distribution of carbon in a soil profile generally shows an age continuum with depth. Aged soil carbon is often the result of sorptive preservation, a physical mechanism that protects organic matter (OM) from microbial decay. Sorptive preservation is, however, a reversible process. Upon desorption, previously protected OM could be available for decomposition. Here we present simple fresh and salt water desorption experiments designed to determine the amount, 14C age and lability of {\textquotedblleft}reversible{\textquotedblright} OM. Results suggest that 1.1{\textendash}3.9\% and 1.5{\textendash}6.7\% of OC, and 0.7{\textendash}3\% and 0.6{\textendash}5\% of total soil nitrogen can be desorbed using fresh and salt water, respectively. Radiocarbon data suggest this desorbed carbon is Δ14C-enriched compared to the bulk soil, with Δ14C values close to modern atmospheric Δ14CO2 at the soil surface, and aging with depth. Of this extractable aged carbon, upwards of 23{\textendash}56\% is labile across all treatments and with depth. Additional carbon is extracted with salt water compared to fresh water and this surplus is non-labile and younger than the labile component. Radiocarbon dating shows that the 14C age of soil carbon increases with depth and that there is a pool of Δ14C-depleted OC that is readily remineralized upon entering an aquatic/marine environment. These results indicate that eroded soil particles can release OC and organic N when entering rivers and oceans and that up to 50\% of this carbon is available for aquatic metabolism.},
	doi = {10.1016/j.orggeochem.2007.05.011},
	author = {Butman, D. and Raymond, P. A. and Oh, N. H. and Mull, K.}
}
@conference {1775,
	title = {Regional variability in the ages and reactivities of riverine dissolved and particulate organic matter exported to a temperate ocean margin},
	booktitle = {ASLO Aquatic Sciences Meeting},
	year = {2007},
	note = {id: 477},
	month = {2007},
	address = {Santa Fe, NM},
	author = {Bauer, J. E. and Raymond, P. A. and Cole, J. J. and Petsch, S. T. and Longworth, B. E. and Caraco, N. F. and Keesee, E. J.}
}
@conference {1638,
	title = {A geostatistical approach to watershed sources of aged riverine organic matter to the Hudson-Mohawk River system},
	booktitle = {American Geophysical Union Fall Meeting},
	year = {2006},
	note = {id: 483},
	month = {2006},
	address = {San Francisco, CA},
	author = {Longworth, B. E. and Petsch, S. T. and Raymond, P. A. and Bauer, J. E.}
}
@conference {1725,
	title = {Organic Carbon in Rivers (Plenary Lecture)},
	booktitle = {Geochemical Earth Reference Model (GERM) Workshop},
	year = {2006},
	note = {id: 488},
	month = {2006},
	address = {Lamont-Doherty},
	author = {Raymond, P. A.}
}
@conference {1790,
	title = {Sources age and composition of dissolved and particulate organic matter delivered to a passive margin river system},
	booktitle = {ASLO/AGU Ocean Science Meeting},
	year = {2006},
	note = {id: 485},
	month = {2006},
	address = {Honolulu, HI},
	author = {Petsch, S. T. and Gordon, E. S. and Longworth, B. E. and Schillawki, S. E. and Raymond, P. A.}
}
@conference {1791,
	title = {Sources, fate and turnover of terrestrial organic carbon in rivers},
	booktitle = {Goldschmidt Conference},
	year = {2006},
	note = {id: 489},
	month = {2006},
	address = {Melbourne, Australia},
	author = {Raymond, P. A.}
}
@conference {1792,
	title = {Sources, fate and turnover of terrestrial organic carbon in rivers (Lecture)},
	booktitle = {Organic Geochemistry Gordon Conference},
	year = {2006},
	note = {id: 491},
	month = {2006},
	address = {Plymouth, NH},
	author = {Raymond, P. A. and Oh, N. H.}
}
@conference {1823,
	title = {Variability in the character, age and reactivity of organic matter exported from rivers and estuaries to ocean margins},
	booktitle = {Ocean Sciences Meeting},
	year = {2006},
	note = {id: 476},
	month = {2006},
	address = {Honolulu, HI},
	author = {Bauer, J. E. and Cole, J. J. and Caraco, N. F. and Raymond, P. A. and Keesee, E. J. and Fernald, S. and Mull, K.}
}
@conference {1584,
	title = {Carbon Isotopes in Riverine Systems},
	booktitle = {Lindeman Speaker, Department of Ecology, Evolution and Behavior},
	year = {2005},
	note = {id: 487},
	month = {2005},
	address = {University of Minnesota},
	author = {Raymond, P. A.}
}
@article {1974,
	title = {The composition and transport of organic carbon in rainfall: insights from the natural (13C and 14C) isotopes of carbon},
	journal = {Geophysical Research Letters},
	volume = {32},
	year = {2005},
	note = {id: 599},
	month = {2005},
	author = {Raymond, P. A.}
}
@article {1965,
	title = {A decrease in discharge-normalized DOC export by the Yukon River during summer through autumn},
	journal = {Geophysical Research Letters},
	volume = {32},
	year = {2005},
	note = {985cuTimes Cited:163
Cited References Count:28
},
	month = {Nov 12},
	abstract = {Climate warming is having a dramatic effect on the vegetation distribution and carbon cycling of terrestrial subarctic and arctic ecosystems. Here, we present hydrologic evidence that warming is also affecting the export of dissolved organic carbon and bicarbonate (DOC and HCO3-) at the large basin scale. In the 831,400 km(2) Yukon River basin, water discharge (Q) corrected DOC export significantly decreased during the growing season from 1978 - 80 to 2001 - 03, indicating a major shift in terrestrial to aquatic C transfer. We conclude that decreased DOC export, relative to total summer through autumn Q, results from increased flow path, residence time, and microbial mineralization of DOC in the soil active layer and groundwater. Counter to current predictions, we argue that continued warming could result in decreased DOC export to the Bering Sea and Arctic Ocean by major subarctic and arctic rivers, due to increased respiration of organic C on land.},
	keywords = {alaska, arctic-ocean, climate-change, CO2, discontinuous permafrost, dissolved organic-carbon, flux, MATTER, tundra},
	isbn = {0094-8276},
	doi = {10.1029/2005GL024413},
	url = {http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2\&amp;SrcAuth=Alerting\&amp;SrcApp=Alerting\&amp;DestApp=WOS\&amp;DestLinkType=FullRecord;UT=WOS:000233354500009},
	author = {Striegl, R. G. and Aiken, G. R. and Dornblaser, M. M. and Raymond, P. A. and Wickland, K. P.}
}
@conference {1657,
	title = {An investigation of accurate gas exchange measurements for determing a large river carbon isotope mass balance},
	booktitle = {37th Liege International Colloquium on Gas Transfer at Water Survaces},
	year = {2005},
	note = {id: 490},
	month = {2005},
	address = {Liege, Belgium},
	author = {Raymond, P. A. and McGillis, W. R. and Bauer, J. E. and Caraco, N. F. and Cole, J. J.}
}
@conference {1726,
	title = {Organic matter inputs and metabolism in a large river estuary (the Hudson): Insights from natural abundance isotopes and whole system metabolism},
	booktitle = {American Society of Limnology and Oceanography},
	year = {2005},
	note = {id: 478},
	month = {2005},
	address = {Salt Lake City, UT},
	author = {Caraco, N. F. and Cole, J. J. and Raymond, P. A. and Bauer, J. E.}
}
@article {2028,
	title = {Controls on the variability of organic matter and dissolved inorganic carbon ages in northeast U.S. rivers},
	journal = {Marine Chemistry},
	volume = {92},
	year = {2004},
	note = {id: 967},
	month = {2004},
	pages = {353-366},
	author = {Raymond, P. A. and Bauer, J. E. and Caraco, N. F. and Cole, J. J. and Longworth, B. E. and Petsch, S. T.}
}
@conference {1563,
	title = {Ancient organic matter sources to the Hudson-Mohawk River system: implications of riverine transport of ancient organic matter for the global biogeochemical},
	booktitle = {American Geophysical Union (AGU)},
	year = {2003},
	note = {id: 1027},
	month = {2003},
	address = {San Francisco, CA},
	author = {Longworth, B. E. and Raymond, P. A. and Petsch, S. T.}
}
@article {615,
	title = {Ecosystem modulation of dissolved carbon age in a temperate marsh-dominated estuary},
	journal = {Ecosystems},
	volume = {6},
	year = {2003},
	note = {746zrTimes Cited:42Cited References Count:73},
	month = {Nov},
	pages = {694-705},
	abstract = {We measured the concentrations and isotopic values (Delta(14)C and delta(13)C) of dissolved inorganic, dissolved organic, and particulate organic carbon (DIC, DOC, and POC, respectively) in the Parker River watershed and estuary in Massachusetts, USA, to determine the age of carbon (C) entering the estuary and how estuarine processing affects the quantity and apparent age of C transported to the Gulf of Maine. The watershed measurements indicated the transport of Delta(14)C-enriched modern DIC and DOC and variably aged POC from the watershed to the estuary. The transport of organic matter from the watershed was dominated by DOC transport, with POC making up less than 10\% of the total. Surveys within the watershed aimed at determining which land-use type dominated the DOC export indicated that wetlands, although they made up only around 20\% of the land use, could be responsible for approximately 75\% of the DOC export. We therefore conclude that the wetland land uses of the Parker River watershed are exporting mainly Delta(14)C-enriched modem DOC. DIC isotopes indicate that the source of DIC in the Parker River watershed is dominated by the weathering of noncarbonate parent material by Delta(14)C-enriched carbon dioxide (CO2) originating from the respiration of young organic matter in soils. Transects in the estuary displayed net additions of all C species. For DOC and DIC, the export of this internally added DOC and DIC was approximately equal to the amount being exported from the watershed, showing the importance of focusing on estuaries when estimating the export of C to the coastal ocean. With respect to DIC, the total input is even larger when the atmospheric exchange of excess PCO2 is calculated. The Delta(14)C -DOC and Delta(14)C-DIC transects indicate that the internally added DOC and DIC is Delta(14)C-enriched modern material. The source of this material is the fringing marshes and estuarine phytoplankton, with the relative importance of these two sources changing over time. Taken together, the bulk C and Delta(14)C measurements show that the estuary is adding significant quantities of young DOC despite the presence of vast quantities of old marsh peat flanking the entire estuary. Furthermore, the DIC data indicate that Delta(14)C-enriched modern material is what is fueling the majority of heterotrophic respiration within the system.},
	issn = {1432-9840},
	doi = {10.1007/s10021-002-0213-6},
	author = {Raymond, P. A. and Hopkinson, C. S.}
}
@conference {1631,
	title = {Evaluating system-specific variability in riverine organic matter ages: implications for determining terrestrial contributions to oceanic DOC},
	booktitle = {Symposium on New Approaches in Marine Organic Biogeochemistry},
	year = {2003},
	note = {id: 486},
	month = {2003},
	address = {Friday Harbor Laboratory, Seattle, WA},
	author = {Raymond, P. A.}
}
@article {2133,
	title = {Use of 14C and 13C natural abundances for evaluating riverine, estuarine, and coastal DOC and POC sources and cycling: Review and Synthesis},
	journal = {Org. Geochem},
	volume = {32},
	year = {2001},
	note = {id: 278},
	month = {2001},
	pages = {469-485},
	author = {Raymond, P. A. and Bauer, J. E.}
}
