Application of a distributed 2D overland flow model for rainfall/runoff and erosion simulation in a Mediterranean watershed

Abstract

Soil erosion has reemerged as an environmental problem associated with climate change that requires the help of simulation tools for forecasting future consequences. This topic becomes even more relevant in Mediterranean catchments due to the highly variable and irregular rainfall regime. Hence, an approach that includes the rainfall/runoff and erosion phenomena is required for quantifying the amount of soil the catchments are transferring to the rivers. As the calibration process of the infiltration and erosion parameters can become cumbersome in terms of iterations to the optimal values to fit experimental data, a Simplified Catchment Model (SCM) is introduced as a first approach. The set of tuning constants that provides the best fit are used as input for re-calibrating the parameters by means of the simulation of the real catchment. The modeling effort here presented opens its application to the analysis of the hydro-sedimentary processes at larger temporal and spatial scales.

A Process-Based, Fully Distributed Soil Erosion and Sediment Transport Model for WRF-Hydro

“…Among all the erosive agents, water is the most prevalent and usually dominates. Moreover, due to the current climate change, the frequency, and the intensity of extreme rainfall events are projected to increase, which will lead to more intensive erosion [2]. With this in mind, a lot of soil erosion models have been developed to mainly simulate water-induced erosion.…”

“…Notable examples are LISEM (LImburg Soil Erosion Model [11]), SHESED [12] and CASC2D-SED (CASCade 2 dimensional sediment model [13]). Recently, a physically based hydrological and soil erosion model has been developed by coupling the Soil Conservation Service model with a 2D fully Dynamic Wave model and a Hillslope Erosion model by Juez et al [2] The model is applied over a Mediterranean watershed to simulate the rainfall-runoff and soil erosion process during two rainfall events with satisfactory results generated. An efficient approach has been applied on the model for calibration process, which has largely reduced the computational cost.…”

A 2D finite volume simulation tool to enable the assessment of combined hydrological and morphodynamical processes in mountain catchments

“…In the last decades, the increasing awareness of the relevance of catchmentscale hydrology and morphodynamics led to numerous authors to develop numerical models able to simulate different physical processes in mountain basins, such as distributed rainfall-runoff conversion [4,5,6], infiltration-exfiltration processes related to the groundwater flow [7,8,9] or sediment dynamics (erosiondeposition and morphodynamics changes in the watershed) [10,11,12]. Recent reviews of the state of the art of both branches are covered in [13] and [14].…”

“…To the authors' knowledge this approach is not extended. The work is oriented to show that traditionally used simplified models, such as diffusive (zero-inertia) or kinematic wave models for the overland flow or hill-slope erosion models for the erosive part [12,20], can be replaced by the shallow water equations based models. Also, the novelty of our approach is oriented to show the interest of combining robust and well balanced finite volume simulation schemes for both the hydrological flow and the sediment transport.…”

Watershed Sediment and Its Effect on Storage Capacity: Case Study of Dokan Dam Reservoir

“…Another technique is used for flow and erosion, and sediment transport is the distributed mode. Juez et al [18] simulates the hydro-sedimentary response of the Western Mediterranean catchment to a representative rainfall storm. The simulation combines the distributed flow surface model with the empirical model for infiltration, the Soil Conservation Services Model (SCS), and the erosion model, which is the Hillslope Erosion Model (HEM), considering water depth and flow as a 2D model.…”