TY - JOUR

T1 - Representation of dissolved organic carbon in the JULES land surface model (vn4.4-JULES-DOCM)

AU - Nakhavali, Mahdi

AU - Friedlingstein, Pierre

AU - Lauerwald, Ronny

AU - Tang, Jing

AU - Chadburn, Sarah

AU - Camino-Serrano, Marta

AU - Guenet, Bertrand

AU - Harper, Anna

AU - Walmsley, David

AU - Peichl, Matthias

AU - Gielen, Bert

PY - 2018/2/12

Y1 - 2018/2/12

N2 - Current global models of the carbon (C) cycle consider only vertical gas exchanges between terrestrial or oceanic reservoirs and the atmosphere, thus not considering the lateral transport of carbon from the continents to the oceans. Therefore, those models implicitly consider all of the C which is not respired to the atmosphere to be stored on land and hence overestimate the land C sink capability. A model that represents the whole continuum from atmosphere to land and into the ocean would provide a better understanding of the Earth's C cycle and hence more reliable historical or future projections. A first and critical step in that direction is to include processes representing the production and export of dissolved organic carbon in soils. Here we present an original representation of dissolved organic C (DOC) processes in the Joint UK Land Environment Simulator (JULES-DOCM) that integrates a representation of DOC production in terrestrial ecosystems based on the incomplete decomposition of organic matter, DOC decomposition within the soil column, and DOC export to the river network via leaching. The model performance is evaluated in five specific sites for which observations of soil DOC concentration are available. Results show that the model is able to reproduce the DOC concentration and controlling processes, including leaching to the riverine system, which is fundamental for integrating terrestrial and aquatic ecosystems. Future work should include the fate of exported DOC in the river system as well as DIC and POC export from soil.

AB - Current global models of the carbon (C) cycle consider only vertical gas exchanges between terrestrial or oceanic reservoirs and the atmosphere, thus not considering the lateral transport of carbon from the continents to the oceans. Therefore, those models implicitly consider all of the C which is not respired to the atmosphere to be stored on land and hence overestimate the land C sink capability. A model that represents the whole continuum from atmosphere to land and into the ocean would provide a better understanding of the Earth's C cycle and hence more reliable historical or future projections. A first and critical step in that direction is to include processes representing the production and export of dissolved organic carbon in soils. Here we present an original representation of dissolved organic C (DOC) processes in the Joint UK Land Environment Simulator (JULES-DOCM) that integrates a representation of DOC production in terrestrial ecosystems based on the incomplete decomposition of organic matter, DOC decomposition within the soil column, and DOC export to the river network via leaching. The model performance is evaluated in five specific sites for which observations of soil DOC concentration are available. Results show that the model is able to reproduce the DOC concentration and controlling processes, including leaching to the riverine system, which is fundamental for integrating terrestrial and aquatic ecosystems. Future work should include the fate of exported DOC in the river system as well as DIC and POC export from soil.

KW - Ecosystems Research

UR - http://www.scopus.com/inward/record.url?scp=85041909232&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/4dfecddc-ede7-34b7-9cda-44814b9621f7/

U2 - 10.5194/gmd-11-593-2018

DO - 10.5194/gmd-11-593-2018

M3 - Journal articles

AN - SCOPUS:85041909232

VL - 11

SP - 593

EP - 609

JO - Geoscientific Model Development

JF - Geoscientific Model Development

SN - 1991-959X

IS - 2

ER -