Anthropogenic Forcing of Carbonate and Organic Carbon Preservation in Marine Sediments.
Carbon preservation in marine sediments, supplemented by that in large lakes, is the primary mechanism that moves carbon from the active surficial carbon cycle to the slower geologic carbon cycle. Preservation rates are low relative to the rates at which carbon moves between surface pools, which has led to the preservation term largely being ignored when evaluating anthropogenic forcing of the global carbon cycle. However, a variety of anthropogenic drivers-including ocean warming, deoxygenation, and acidification, as well as human-induced changes in sediment delivery to the ocean and mixing and irrigation of continental margin sediments-all work to decrease the already small carbon preservation term. These drivers affect the cycling of both carbonate and organic carbon in the ocean. The overall effect of anthropogenic forcing in the modern ocean is to decrease delivery of carbon to sediments, increase sedimentary dissolution and remineralization, and subsequently decrease overall carbon preservation.
School of Oceanography, University of Washington, Seattle, Washington 98195-5351; email: rickkeil@uw.edu.
Richard
R
Keil
D002244:Carbon; D057486:Carbon Cycle; D002245:Carbon Dioxide; D002254:Carbonates; D019015:Geologic Sediments; D009792:Oceans and Seas
D002254:Carbonates; D002245:Carbon Dioxide; D002244:Carbon
Anthropocene; anthropogenic; carbonate; climate change; global carbon cycle; organic carbon; preservation; sediment