Net ecosystem production and organic carbon balance of U.S. East Coast estuaries: A synthesis approach
Tóm tắt
Net ecosystem production (NEP) and the overall organic carbon budget for the estuaries along the East Coast of the United States are estimated. We focus on the open estuarine waters, excluding the fringing wetlands. We developed empirical models relating NEP to loading ratios of dissolved inorganic nitrogen to total organic carbon, and carbon burial in the sediment to estuarine water residence time and total nitrogen input across the landward boundary. Output from a data‐constrained water quality model was used to estimate inputs of total nitrogen and organic carbon to the estuaries across the landward boundary, including fluvial and tidal‐wetland sources. Organic carbon export from the estuaries to the continental shelf was computed by difference, assuming steady state. Uncertainties in the budget were estimated by allowing uncertainties in the supporting model relations. Collectively, U.S. East Coast estuaries are net heterotrophic, with the area‐integrated NEP of −1.5 (−2.8, −1.0) Tg C yr−1 (best estimate and 95% confidence interval) and area‐normalized NEP of −3.2 (−6.1, −2.3) mol C m−2 yr−1. East Coast estuaries serve as a source of organic carbon to the shelf, exporting 3.4 (2.0, 4.3) Tg C yr−1 or 7.6 (4.4, 9.5) mol C m−2 yr−1. Organic carbon inputs from fluvial and tidal‐wetland sources for the region are estimated at 5.4 (4.6, 6.5) Tg C yr−1 or 12 (10, 14) mol C m−2 yr−1 and carbon burial in the open estuarine waters at 0.50 (0.33, 0.78) Tg C yr−1 or 1.1 (0.73, 1.7) mol C m−2 yr−1. Our results highlight the importance of estuarine systems in the overall coastal budget of organic carbon, suggesting that in the aggregate, U.S. East Coast estuaries assimilate (via respiration and burial) ~40% of organic carbon inputs from fluvial and tidal‐wetland sources and allow ~60% to be exported to the shelf.
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Tài liệu tham khảo
Axelrad D. M., 1976, Nitrogen, Phosphorus, and Carbon Flux in Chesapeake Bay marshes
Bricker S. B., 1999, National Estuarine Eutrophication Assessment: Effects of Nutrient Enrichment in the Nation's Estuaries
Bricker S. B., 2007, Effects of Nutrient Enrichment in the Nation's Estuaries: A Decade of Change
Childers D. L., 2000, Concepts and Controversies in Tidal Marsh Ecology, 391
Dame R. F., 1995, The net flux of materials between marsh‐estuarine systems and the sea: The Atlantic coast of the United States, Oceanogr. Lit. Rev., 42
Denning A. S., 2005, Science Implementation Strategy for the North American Carbon Program
Dyer K. R., 1997, Estuaries: A Physical Introduction
Hales B., 2008, North American Continental Margins: A Synthesis and Planning Workshop
Kennedy V. S.(1984) The estuary as a filter in Proceedings of the Seventh Biennial International Estuarine Research Conference Virginia Beach Virginia October 23–26 1983 511pp.
National Oceanic and Atmospheric Administration (NOAA), 1985, National Estuarine Inventory Data Atlas, Volume 1: Physical and Hydrologic Characteristics
Odum E. P.(1968) A research challenge: Evaluating the productivity of coastal and estuarine water in Proceedings of the Second Sea Grant Conference pp.63–64.
Redfield A. C., 1963, The Influence of Organisms on the Composition of Seawater, in The Sea, 26
Seaber P. R., 1987, Hydrologic Unit Maps
Shih J. S., 2010, An Initial SPARROW Model of Land Use and in‐Stream Controls on Total Organic Carbon in Streams of the Conterminous United States, U.S. Geol. Surv. Open File Rep., 2010–1276
Wilks D. S., 2006, Statistical Methods in the Atmospheric Sciences