Performance of the RothC-26.3 model in short-term experiments in Mexican sites and systems

Abstract

SUMMARYInformation on the performance of the Rothamsted organic carbon turnover model (RothC model) in predicting changes in soil organic carbon (SOC) in short-term experiments is scarce. In Mexico, it was found that these experiments covered not more than 20 years. The purpose of the present study was to evaluate short-term SOC prediction performance of the RothC model in the following systems: (1) farming with residues added (A+R), (2) farming with no added residues (A−R), (3) pure forest stands (F), (4) grasslands (GR) and (5) rangeland (RL). Work was done in five experimental sites: Atécuaro, Michoacán; Santiago Tlalpan, Tlaxcala; El Batán, State of Mexico; Sierra Norte, Oaxaca; and Linares, Nuevo León. Carbon (C) inputs to the soil were plant residues and organic fertilizers, which need to be known to operate the RothC model. The adjustment coefficients for site modelling had R2 values of 0·77–0·95 and model efficiency (EF) was −0·60 to 0·93. When RothC performance was evaluated by a system, R2 values were 0·06–0·92 and EF was −0·24 to 0·90. The low R2 and EF values in rangelands were attributed to the fact that these systems are complex because of heterogeneous vegetation, soil and climate. In general, the evaluation of the RothC model indicates that it can be useful in simulating SOC changes in temperate and warm climate sites and in farming, forest and grassland systems in Mexico.

Simulation of soil organic carbon changes in Vertisols under conservation tillage using the RothC model

“…MSRE values were in the range of 12-16 %, lower than those reported by Gonzalez-Molina et al (2011) for agricultural systems in Mexico (25-36 %). ER was in the range of -6 to 8 %.…”

National‐scale estimates of forest root biomass carbon stocks and associated carbon fluxes in Canada

“…However, there are several potential changes to the CBM‐CFS3 which could improve predictions at a regional scale. Root productivity, turnover, and decay rates are site and species specific [ Bauhus and Messier , ; Currie et al ., ; Finér et al ., ; González‐Molina et al ., ; Gower et al ., ; Stover et al ., ; Yuan and Chen , ], but these fine‐scale dynamics are presently unaccounted for in the model. Root diseases have not been included in the model, but these could alter mortality, root to stem biomass proportions, and reduce long‐term site potential [ Cruickshank et al ., ].…”

Implications of input estimation, residue quality and carbon saturation on the predictive power of the Rothamsted Carbon Model

“…SOC in cropland is a potential source or sink for CO 2 , thereby affecting climate and food security (Lal, 2004;Paustian et al, 2000). Models simulating SOC dynamics may be useful to quantify changes in SOC due to general land use change (Gonzalez-Molina et al, 2011), cropland management such as fertilisation and organic amendment (Ludwig et al, 2010;Paustian et al, 1992;Powlson et al, 2011) and to deepen understanding on C-sequestration processes (Henriksen and Breland, 1999;Leifeld et al, 2008;Ludwig et al, 2007).…”