Implementation of a distributed sediment model in different data availability scenarios.

Abstract

Soil erosion by water can cause agricultural soil losses, desertification, water pollution, reservoir sedimentation, local excess of erosion (such as bridge scour) or deposition, etc. For this reason, the assessment of soil erosion and sediment transport is a key component of integrated catchment management. One of the most useful and up-to-date tools available to catchment managers for soil erosion and sediment transport assessment is distributed modelling. During the last few decades, many sedimentological distributed models were developed and applied for a wide range of climates and basins. Their main advantage is that they allow spatial interpolation or extrapolation of their results. Nevertheless, their use is still limited by some constraints. One of the most relevant limitations to the use of such models is the lack of recorded sediment transport data to be used for model calibration and validation. It is widely recognised that both sediment discharge series and soil erosion measurements are only available in a few and small-to medium-size experimental catchments. The aim of this dissertation is to investigate the possibility of using reservoir sedimentation data as a source of proxy information for sedimentological model calibration and validation. In order to carry out this task, a distributed sedimentological model called TETIS was tested in set of catchments with different sediment data availability. First of all, the TETIS model, developed over the last years by the research group of hydrological and environmental modelling of the Technical University of Valencia, is described, especially focusing on the new features developed within this dissertation (sedimentological sub-model automatic calibration algorithm, small pond sediment retention module, etc.). Then, the model is applied to three catchments with different sediment data availability. The first case-study is the Goodwin Creek catchment (Mississippi, US), an experimental catchment with high sediment transport data availability. The model performance is evaluated, and some considerations are made on the estimation of the sediment volume deposited into the drainage network at the beginning of a rainstorm. The second case-study is the Rambla del Poyo catchment (Valencia, Spain), a medium size semi-arid catchment draining to a coastal lagoon with severe sedimentation problems. The TETIS sedimentological sub-model is calibrated and validated using checkdam sedimentation volumes as an estimator of the total sediment transport. A detailed description of the alluvial stratigraphy infilling a check dam that drains a 12.9 km 2 subcatchment was used as indirect information of sediment yield data. A further application was also developed in this catchment in order to investigate the possibility of calibrating and validating both the hydrological and the sediment sub-models by using reservoir sedimentation volumes and employing neither water nor sediment discharge direct records. The third case-study is the Ésera River catchment (Huesca, Spain), a...

Self-organized criticality in river basins: Challenging sedimentary records of environmental change

“…This erosion that is more recurrent than landslides is often modelled as surface erosion via USLE parameterizations (e.g. Bussi (2014)) at event to seasonal scale. On the other hand, at geomorphology scale about centuries, dynamic colluvium storage is modelled as a simplified system in hollows or headwater streams, whose input comes by erosion and mass wasting, and whose output is just estimated by empirical coefficients (Allen & Hovius, 1998) and transited through the low order streams of the drainage network (Lee Benda & Dunne, 1997).…”

Modelado de la producción de sedimentos en una cuenca con poca información incluyendo los potenciales efectos del cambio climático y el cambio de uso de suelo

“…ISSN online 2007-9621 Ramos Castillo, L. A., & Orozco Medina, I. Modelado de la producción de sedimentos en una cuenca con poca información incluyendo los potenciales efectos del cambio climático y el cambio de uso de suelo | 1-19 El submodelo sedimentológico de TETIS utiliza en la estimación de la capacidad del transporte en zonas de ladera (Qh) la ecuación de Kilinc y Richardson, modificada por Bussi (2014). Según Bussi (2014), la Ecuación 1 depende del caudal, la pendiente del terreno, el tipo de suelo y los usos de la tierra.…”

“…El submodelo sedimentológico utiliza de forma distribuida los parámetros K, C, P y los porcentajes de arena, limo y arcilla (Bussi, 2014). En la figura 6 se presentan los parámetros obtenidos para el submodelo sedimentológico, estimados usando información geográfica e imágenes de satélite.…”

“…De acuerdo con Bussi (2014), estos parámetros introducen una elevada incertidumbre en la simulación de los procesos de producción y transporte de sedimentos. Es por ello que a través de los ISSN online 2007-9621 Ramos Castillo, L. A., & Orozco Medina, I. Modelado de la producción de sedimentos en una cuenca con poca información incluyendo los potenciales efectos del cambio climático y el cambio de uso de suelo | 1-19 calibración manual o automática.…”

“…a) Esquema conceptual del movimiento vertical de los flujos del modelo TETIS; b) y c) esquema del transporte de sedimentos en ladera y en canales del submodelo sedimentológico. Fuente:Francés et al (2007) yBussi (2014).…”