LORICA – A new model for linking landscape and soil profile evolution: Development and sensitivity analysis

• Published in: Computers & geosciences Vol. 90; pp. 131 - 143
• Main Authors: Temme, Arnaud J.A.M., Vanwalleghem, Tom
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.05.2016
• Subjects: Bodemgeografie en Landschap; catenas; clay; Computer simulation; computers; Determinants; Evolution; Landscape evolution modelling; landscape position; Landscapes; LORICA; Mathematical models; particle size; particle size distribution; PE&RC; Sensitivity analysis; Soil (material); Soil erosion; soil formation; Soil Geography and Landscape; Soil modelling; soil profiles; soil properties; Soilscape; Soil–landscape modelling; vegetation; weathering; Soilscape; Sensitivity analysis; Landscape evolution modelling; Soil–landscape modelling; LORICA; Soil modelling
• ISSN: 0098-3004; 1873-7803
• DOI: 10.1016/j.cageo.2015.08.004

Soils and landscapes evolve in tandem. Landscape position is a strong determinant of vertical soil development, which has often been formalized in the catena concept. At the same time, soil properties are strong determinants of geomorphic processes such as overland erosion, landsliding and creep. We present a new soilscape evolution model; LORICA, to study these numerous interactions between soil and landscape development. The model is based on the existing landscape evolution model LAPSUS and the soil formation model MILESD. The model includes similar soil formation processes as MILESD, but the main novelties include the consideration of more layers and the dynamic adaption of the number of layers as a function of the soil profile's heterogeneity. New processes in the landscape evolution component include a negative feedback of vegetation and armouring and particle size selectivity of the erosion–deposition process. In order to quantify these different interactions, we present a full sensitivity analysis of the input parameters. First results show that the model successfully simulates various soil–landscape interactions, leading to outputs where the surface changes in the landscape clearly depend on soil development, and soil changes depend on landscape location. Sensitivity analysis of the model confirms that soil and landscape interact: variables controlling amount and position of fine clay have the largest effect on erosion, and erosion variables control among others the amount of chemical weathering. These results show the importance of particle size distribution, and especially processes controlling the presence of finer clay particles that are easily eroded, both for the resulting landscape form as for the resulting soil profiles. Further research will have to show whether this is specific to the boundary conditions of this study or a general phenomenon. •We present a new soil–landscape model: LORICA.•Model assumptions and equations are discussed.•Example results appear satisfactory.•Global sensitivity analysis is performed.•Soil and landscape development are intimately linked.