Impacts of Eutrophication on Carbon Burial in Freshwater Lakes in an Intensively Agricultural Landscape
- 1.1k Downloads
The influence of inland water bodies on the global carbon cycle and the great potential for long-term carbon burial in them is an important component of global limnology. We used paleolimnological methods to estimate changes in carbon burial rates through time in a suite of natural lakes in the US state of Iowa which has watersheds that have been heavily modified over the last 150 years. Our results show increasing carbon burial for all lakes in our study as agriculture intensified. Our estimates of carbon burial rates, before land clearance, are similar to the published worldwide averages for nutrient-poor lakes. In nearly all the cases, burial rates increased to very high levels (up to 200 g C m−2 y−1) following agricultural development. These results support the idea that the increased autochthonous and allochthonous carbon flux, related to anthropogenic change, leads to higher rates of carbon burial. Further, these results imply that the fraction of global carbon buried by lakes will be increasingly important in the future if worldwide trends in anthropogenic eutrophication continue.
Keywordscarbon burial eutrophication paleolimnology sediment agriculture global change organic matter
This study was funded by the Iowa Department of Natural Resources and was inspired by the ITAC (Integration of the Terrestrial and Aquatic Carbon) Working Group supported by the National Center for Ecological Analysis and Synthesis, a Center funded by NSF (Grant DEB-94-21535), the University of California at Santa Barbara, and the State of California. The authors would like to thank Joy Ramstack, Mark Edlund, Dan Engstrom, and Erin Mortenson at the St. Croix Watershed Research Station for their assistance in the field and technical advice in the laboratory, as well as Kristina Brady and Amy Mybro at the Limnological Research Center for their assistance in core processing. The authors would also like to thank Charles Umbanhowar, Jr., for the use of his piston corer. Special thanks to Patricia Soranno and the Anonymous Reviewers 1 and 2 for their helpful comments on this manuscript.
- Anderson PF. 1997. GIS research to digitize maps of Iowa 1832–1859 vegetation from General Land Office township plat maps. Des Moines, IA: Iowa Department of Natural Resources.Google Scholar
- Bachmann RW, Jones JR. 1974. Water quality in the Iowa Great Lakes: a report to the Iowa Great Lakes Water Quality Control Plan. Ames, IA: Iowa Agricultural and Home Economics Experiment Station Project.Google Scholar
- Balmer MB, Downing JA. 2011. Carbon dioxide concentrations in eutrophic lakes: undersaturation implies atmospheric uptake. Inland Waters 1:125–32.Google Scholar
- Cleveland WS, Grosse E, Shyu WM. 1992. Local regression models. In: Chambers JM, Hastie TJ, Eds. Statistical models in S. Boca Raton, FL: Chapman & Hall. p 309–76.Google Scholar
- Dean WE. 1974. Determination of carbonate and organic-matter in calcareous sediments and sedimentary-rocks by loss on ignition—comparison with other methods. J Sediment Petrol 44:242–8.Google Scholar
- Downing JA. 2003. Looking into Earth’s eye: a watershed view of clear lakes. Des Moines, IA: Iowa Natural Heritage Foundation. pp 8–11.Google Scholar
- ESRI. 2008. ArcMap 9.3. Redlands, CA: Environmental Research Systems Institute.Google Scholar
- Mutel CF. 2008. The emerald horizon: the history of nature in Iowa. Iowa City, IA: University of Iowa Press.Google Scholar
- Risser J. 1981. A renewed threat of soil-erosion—its worse than the dust bowl. Smithsonian 11:120–31.Google Scholar
- Stumm W, Morgan JJ. 1996. Aquatic chemistry: chemical equilibria and rates in natural waters. New York: Wiley.Google Scholar
- Tranvik LJ, Downing JA, Cotner JB, Loiselle SA, Striegl RG, Ballatore TJ, Dillon P, Finlay K, Fortino K, Knoll LB, Kortelainen PL, Kutser T, Larsen S, Laurion I, Leech DM, McCallister SL, McKnight DM, Melack JM, Overholt E, Porter JA, Prairie Y, Renwick WH, Roland F, Sherman BS, Schindler DW, Sobek S, Tremblay A, Vanni MJ, Verschoor AM, von Wachenfeldt E, Weyhenmeyer GA. 2009. Lakes and reservoirs as regulators of carbon cycling and climate. Limnol Oceanogr 54:2298–314.CrossRefGoogle Scholar