Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century
Article first published online: 15 FEB 2008
Copyright 2008 by the American Geophysical Union.
Global Biogeochemical Cycles
Volume 22, Issue 1, March 2008
How to Cite
2008), Sediment organic carbon burial in agriculturally eutrophic impoundments over the last century, Global Biogeochem. Cycles, 22, GB1018, doi:10.1029/2006GB002854., , , , , , , and (
- Issue published online: 15 FEB 2008
- Article first published online: 15 FEB 2008
- Manuscript Accepted: 14 SEP 2007
- Manuscript Revised: 13 JUN 2007
- Manuscript Received: 3 OCT 2006
- organic carbon;
 We estimated organic carbon (OC) burial over the past century in 40 impoundments in one of the most intensively agricultural regions of the world. The volume of sediment deposited per unit time varied as a function of lake and watershed size, but smaller impoundments had greater deposition and accumulation rates per unit area. Annual water storage losses varied from 0.1–20% and were negatively correlated with impoundment size. Estimated sediment OC content was greatest in lakes with low ratios of watershed to impoundment area. Sediment OC burial rates were higher than those assumed for fertile impoundments by previous studies and were much higher than those measured in natural lakes. OC burial ranged from a high of 17,000 g C m−2 a−1 to a low of 148 g C m−2 a−1 and was significantly greater in small impoundments than large ones. The OC buried in these lakes originates in both autochthonous and allochthonous production. These analyses suggest that OC sequestration in moderate to large impoundments may be double the rate assumed in previous analyses. Extrapolation suggests that they may bury 4 times as much carbon (C) as the world's oceans. The world's farm ponds alone may bury more OC than the oceans and 33% as much as the world's rivers deliver to the sea.