title: Physical model for the decay and preservation of marine organic carbon.
abstract: Degradation of marine organic carbon provides a major source of atmospheric carbon dioxide, whereas preservation in sediments results in accumulation of oxygen. These processes involve the slow decay of chemically recalcitrant compounds and physical protection. To assess the importance of physical protection, we constructed a reaction-diffusion model in which organic matter differs only in its accessibility to microbial degradation but not its intrinsic reactivity. The model predicts that organic matter decays logarithmically with time t and that decay rates decrease approximately as 0.2 x t(-1) until burial. Analyses of sediment-core data are consistent with these predictions.
authors.affiliation: Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. dhr@mit.edu
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Rothman
authors.forename: David C
authors.initials: DC
authors.lastname: Forney
mesh_terms: D000538:Aluminum Silicates; D001419:Bacteria / Q000378:metabolism*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000378:metabolism; D000077215:Clay; D016208:Databases, Factual; D004058:Diffusion; D004798:Enzymes / Q000378:metabolism; D019015:Geologic Sediments / Q000737:chemistry / Q000382:microbiology; D006868:Hydrolysis; D007700:Kinetics; D008433:Mathematics; D008962:Models, Theoretical; D009792:Oceans and Seas; D009930:Organic Chemicals / Q000737:chemistry / Q000378:metabolism; D010100:Oxygen / Q000032:analysis; D012623:Seawater
chemical_list: D000538:Aluminum Silicates; D004798:Enzymes; D009930:Organic Chemicals; D002244:Carbon; D010100:Oxygen; D000077215:Clay