Articles | Volume 7, issue 3
Geosci. Model Dev., 7, 867–881, 2014
Geosci. Model Dev., 7, 867–881, 2014

Model description paper 14 May 2014

Model description paper | 14 May 2014

Modeling dissolved organic carbon in temperate forest soils: TRIPLEX-DOC model development and validation

H. Wu1,2, C. Peng2,3, T. R. Moore4, D. Hua2,5, C. Li6, Q. Zhu2,3, M. Peichl7, M. A. Arain8, and Z. Guo1 H. Wu et al.
  • 1Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Science, P.O. Box 9825, Beijing 100029, China
  • 2Department of Biology Sciences, Institute of Environment Sciences, University of Quebec at Montreal, C.P. 8888, Succ. Centre-Ville, Montreal H3C 3P8, Canada
  • 3Laboratory for Ecological Forecasting and Global Change, College of Forestry, Northwest A & F University, Yangling, Shaanxi 712100, China
  • 4Department of Geography and Global Environmental and Climate Change Centre, McGill University, Montreal, H3A 0B9, Canada
  • 5Center for Climate Research, University of Wisconsin-Madison, Madison, WI 53706, USA
  • 6Institute for the study of Earth, Ocean and Space, University of New Hampshire, Durham, NH 03824, USA
  • 7Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden
  • 8School of Geography and Earth Sciences and McMaster Centre for Climate Change, McMaster University, Hamilton, Ontario L8S 4K1, Canada

Abstract. Even though dissolved organic carbon (DOC) is the most active carbon (C) cycling in soil organic carbon (SOC) pools, it receives little attention from the global C budget. DOC fluxes are critical to aquatic ecosystem inputs and contribute to the C balance of terrestrial ecosystems, but few ecosystem models have attempted to integrate DOC dynamics into terrestrial C cycling. This study introduces a new process-based model, TRIPLEX-DOC, that is capable of estimating DOC dynamics in forest soils by incorporating both ecological drivers and biogeochemical processes. TRIPLEX-DOC was developed from Forest-DNDC, a biogeochemical model simulating C and nitrogen (N) dynamics, coupled with a new DOC process module that predicts metabolic transformations, sorption/desorption, and DOC leaching in forest soils. The model was validated against field observations of DOC concentrations and fluxes at white pine forest stands located in southern Ontario, Canada. The model was able to simulate seasonal dynamics of DOC concentrations and the magnitudes observed within different soil layers, as well as DOC leaching in the age sequence of these forests. Additionally, TRIPLEX-DOC estimated the effect of forest harvesting on DOC leaching, with a significant increase following harvesting, illustrating that land use change is of critical importance in regulating DOC leaching in temperate forests as an important source of C input to aquatic ecosystems.