ORCHIDEE-SOM: Modeling soil organic carbon (SOC) and dissolved organic carbon (DOC) dynamics along vertical soil profiles in Europe

Publikation: Beiträge in ZeitschriftenZeitschriftenaufsätzeForschungbegutachtet

Authors

  • Marta Camino-Serrano
  • Bertrand Guenet
  • Sebastiaan Luyssaert
  • Philippe Ciais
  • Vladislav Bastrikov
  • Bruno De Vos
  • Bert Gielen
  • Gerd Gleixner
  • Albert Jornet-Puig
  • Klaus Kaiser
  • Dolly Kothawala
  • Ronny Lauerwald
  • Josep Peñuelas
  • Marion Schrumpf
  • Sara Vicca
  • Nicolas Vuichard
  • David Walmsley
  • Ivan A. Janssens

Current land surface models (LSMs) typically represent soils in a very simplistic way, assuming soil organic carbon (SOC) as a bulk, and thus impeding a correct representation of deep soil carbon dynamics. Moreover, LSMs generally neglect the production and export of dissolved organic carbon (DOC) from soils to rivers, leading to overestimations of the potential carbon sequestration on land. This common oversimplified processing of SOC in LSMs is partly responsible for the large uncertainty in the predictions of the soil carbon response to climate change. In this study, we present a new soil carbon module called ORCHIDEE-SOM, embedded within the land surface model ORCHIDEE, which is able to reproduce the DOC and SOC dynamics in a vertically discretized soil to 2gm. The model includes processes of biological production and consumption of SOC and DOC, DOC adsorption on and desorption from soil minerals, diffusion of SOC and DOC, and DOC transport with water through and out of the soils to rivers. We evaluated ORCHIDEE-SOM against observations of DOC concentrations and SOC stocks from four European sites with different vegetation covers: A coniferous forest, a deciduous forest, a grassland, and a cropland. The model was able to reproduce the SOC stocks along their vertical profiles at the four sites and the DOC concentrations within the range of measurements, with the exception of the DOC concentrations in the upper soil horizon at the coniferous forest. However, the model was not able to fully capture the temporal dynamics of DOC concentrations. Further model improvements should focus on a plant- A nd depth-dependent parameterization of the new input model parameters, such as the turnover times of DOC and the microbial carbon use efficiency. We suggest that this new soil module, when parameterized for global simulations, will improve the representation of the global carbon cycle in LSMs, thus helping to constrain the predictions of the future SOC response to global warming.

OriginalspracheEnglisch
ZeitschriftGeoscientific Model Development
Jahrgang11
Ausgabenummer3
Seiten (von - bis)937-957
Anzahl der Seiten21
ISSN1991-959X
DOIs
PublikationsstatusErschienen - 15.03.2018

Dokumente

DOI