title: Terrestrial and marine perspectives on modeling organic matter degradation pathways.
abstract: Organic matter (OM) plays a major role in both terrestrial and oceanic biogeochemical cycles. The amount of carbon stored in these systems is far greater than that of carbon dioxide (CO2 ) in the atmosphere, and annual fluxes of CO2 from these pools to the atmosphere exceed those from fossil fuel combustion. Understanding the processes that determine the fate of detrital material is important for predicting the effects that climate change will have on feedbacks to the global carbon cycle. However, Earth System Models (ESMs) typically utilize very simple formulations of processes affecting the mineralization and storage of detrital OM. Recent changes in our view of the nature of this material and the factors controlling its transformation have yet to find their way into models. In this review, we highlight the current understanding of the role and cycling of detrital OM in terrestrial and marine systems and examine how this pool of material is represented in ESMs. We include a discussion of the different mineralization pathways available as organic matter moves from soils, through inland waters to coastal systems and ultimately into open ocean environments. We argue that there is strong commonality between aspects of OM transformation in both terrestrial and marine systems and that our respective scientific communities would benefit from closer collaboration.
authors.affiliation: Department of Marine Sciences, University of Georgia, Athens, GA, 30602, USA.
authors.forename: Adrian B
authors.initials: AB
authors.lastname: Burd
authors.affiliation: Department of Natural Resources & the Environment, University of New Hampshire, Durham, NH, 03824, USA.
authors.forename: Serita
authors.initials: S
authors.lastname: Frey
authors.affiliation: Department of Earth & Sciences, University of Pennsylvania, Philadelphia, PA, 19104, USA.
authors.forename: Anna
authors.initials: A
authors.lastname: Cabre
authors.affiliation: School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, 30332, USA.
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Ito
authors.affiliation: Department of Biology, University of Southern California, Los Angeles, CA, 90089, USA.
authors.forename: Naomi M
authors.identifier: http://orcid.org/0000-0002-4963-0535
authors.initials: NM
authors.lastname: Levine
authors.affiliation: Australian Institute of Marine Science, PMB 3, Townsville MC, QLD, 4810, Australia.
authors.forename: Christian
authors.initials: C
authors.lastname: Lønborg
authors.affiliation: Climate and Global Dynamics Division, National Center for Atmospheric Research, PO Box 3000, Boulder, CO 80307-3000, USA.
authors.forename: Matthew
authors.initials: M
authors.lastname: Long
authors.affiliation: Center for Ecosystem Science and Society, Department of Biological Sciences, Northern Arizona University, Flagstaff, AZ, 86011, USA.
authors.forename: Marguerite
authors.identifier: http://orcid.org/0000-0001-8733-9119
authors.initials: M
authors.lastname: Mauritz
authors.affiliation: Department of Forest Resources and Environmental Conservation, Virginia Tech, Blacksburg, VA, 24061, USA.
authors.forename: R Quinn
authors.initials: RQ
authors.lastname: Thomas
authors.affiliation: Geosciences Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA, 92093, USA.
authors.forename: Brandon M
authors.initials: BM
authors.lastname: Stephens
authors.affiliation: Department of Agronomy, Leonardo da Vinci Building, Campus Rabanales, Cordoba 14071, Spain.
authors.forename: Tom
authors.initials: T
authors.lastname: Vanwalleghem
authors.affiliation: Department of Atmospheric and Oceanic Science, University of Maryland, College Park, MD, 20742, USA.
authors.forename: Ning
authors.initials: N
authors.lastname: Zeng
mesh_terms: D002244:Carbon / Q000378:metabolism; D057486:Carbon Cycle; D017753:Ecosystem; D008962:Models, Theoretical; D009792:Oceans and Seas; D012987:Soil / Q000737:chemistry
chemical_list: D012987:Soil; D002244:Carbon
keywords: carbon cycles; climate; modeling; organic matter degradation; remineralization