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Sediment Yield Model Implementation Based on Check Dam Infill

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Sediment Yield Model Implementation Based on Check Dam Infill EGU Journal Logos (RGB) Open Access Open Access Open Access Advances in Annales Nonlinear Processes Geosciences Geophysicae in Geophysics Open Access Open Access Natural Hazards Natural Hazards and Earth System and Earth System Sciences Sciences Discussions Open Access Open Access Atmospheric Atmospheric Chemistry Chemistry and Physics and Physics Discussions Open Access Open Access Atmospheric Atmospheric Measurement Measurement Techniques Techniques Discussions Open Access Open Access Biogeosciences Biogeosciences Discussions Open Access Open Access Climate Climate of the Past of the Past Discussions Open Access Open Access Earth System Earth System Dynamics Dynamics Discussions Open Access Geoscientific Geoscientific Open Access Instrumentation Instrumentation Methods and Methods and Data Systems Data Systems Discussions Open Access Open Access Geoscientific Geoscientific Model Development Model Development Discussions Open Access Open Access Hydrol. Earth Syst. Sci., 17, 3339–3354, 2013 Hydrology and Hydrology and www.hydrol-earth-syst-sci.net/17/3339/2013/ doi:10.5194/hess-17-3339-2013 Earth System Earth System © Author(s) 2013. CC Attribution 3.0 License. Sciences Sciences Discussions Open Access Open Access Ocean Science Ocean Science Discussions Sediment yield model implementation based on check dam infill Open Access stratigraphy in a semiarid Mediterranean catchment Open Access Solid Earth Solid Earth G. Bussi1,*, X. Rodr´ıguez-Lloveras2, F. Frances´ 1, G. Benito2, Y. Sanchez-Moya´ 3, and A. Sopena˜ 3 Discussions 1Research Institute of Water and Environmental Engineering (IIAMA), Universitat Politecnica` de Valencia,` Spain 2Geology Department, National Museum of Natural Sciences – CSIC, Madrid, Spain 3Geoscience Institute, CSIC, UCM, Madrid, Spain Open Access Open Access The Cryosphere *Invited contribution by G. Bussi, recipient of the EGU Young Scientists Outstanding PosterThe PaperCryosphere Award 2012. Discussions Correspondence to: G. Bussi ([email protected]) Received: 28 January 2013 – Published in Hydrol. Earth Syst. Sci. Discuss.: 14 March 2013 Revised: 14 June 2013 – Accepted: 20 July 2013 – Published: 29 August 2013 Abstract. Soil loss and sediment transport in Mediterranean 1 Introduction areas are driven by complex non-linear processes which have been only partially understood. Distributed models can Modelling sediment yield is a complex task due to the non- be very helpful tools for understanding the catchment-scale linearity of natural processes intervening at slope and basin phenomena which lead to soil erosion and sediment trans- scale (Schumm and Lichty, 1965; Coulthard et al., 1998; port. In this study, a modelling approach is proposed to re- Roering et al., 1999). Recent computing advances, together produce and evaluate erosion and sediment yield processes with a better understanding of hydrodynamic processes in- in a Mediterranean catchment (Rambla del Poyo, Valencia, volved in the surface runoff, sediment production and sed- Spain). Due to the lack of sediment transport records for iment transport, have stimulated the development of phys- model calibration and validation, a detailed description of ically based and distributed parameter models (e.g. WEPP, the alluvial stratigraphy infilling a check dam that drains a EUROSEM and LISEM). The reliability of such sediment 2 12.9 km sub-catchment was used as indirect information of yield models depends on a robust calibration and/or val- sediment yield data. These dam infill sediments showed ev- idation process that, at ungauged catchments, as it is the idences of at least 15 depositional events (floods) over the case of most of small basins around the world, may limit time period 1990–2009. The TETIS model, a distributed con- a broad use of such models. Different authors have used ceptual hydrological and sediment model, was coupled to the the sediment volume accumulated in lakes and reservoirs Sediment Trap Efficiency for Small Ponds (STEP) model as an indirect validation method for modelling sediment for reproducing reservoir retention, and it was calibrated yield at regional scale (Van Rompaey et al., 2003; Grauso and validated using the sedimentation volume estimated for et al., 2008). Reservoir sediment volumes have been used the depositional units associated with discrete runoff events. since the 1950s as an estimate of the catchment mean sed- The results show relatively low net erosion rates compared iment yield for comparison with the results of empirical −1 −1 to other Mediterranean catchments (0.136 Mg ha yr ), equations. Some examples are Geiger (1957), Ackermann probably due to the extensive outcrops of limestone bedrock, and Corinth (1962), Rohel (1962), Farnham et al. (1966), thin soils and rather homogeneous vegetation cover. The sim- Callander and Duder (1979), Jolly (1982), Le Roux and ulated sediment production and transport rates offer model Roos (1982), Duck and McManus (1993), Avendano˜ Salas satisfactory results, further supported by in-site palaeohy- et al. (1995, 1997) and Verstraeten et al. (2003). drological evidences and spatial validation using additional Recently, sediment volumes stored in water-retention check dams, showing the great potential of the presented dams have also been used for distributed mathematical data assimilation methodology for the quantitative analysis model validation, as shown in De Vente et al. (2005, 2008) of sediment dynamics in ungauged Mediterranean basins. and Alatorre et al. (2010). In De Vente et al. (2005), two Published by Copernicus Publications on behalf of the European Geosciences Union. 3340 G. Bussi et al.: Sediment yield model implementation semi-quantitative models for mean annual net erosion rates (Phillips and Nelson, 1981) or in the Brno reservoir in Czech estimation are compared, and their results contrasted versus Republic (Nehyba et al., 2011). reservoir sedimentation rates. In De Vente et al. (2008), the In Mediterranean ephemeral streams a large number of reservoir sedimentation rates were used to compare the re- check dams have been built to prevent or reduce sediment sults of three distributed approaches for soil erosion rates and inputs into perennial streams during the first winter or rainy long-term sediment yield estimation: the WATEM/SEDEM season following a wildfire (Boix-Fayos et al., 2008) or to model (Van Rompaey et al., 2001), the PESERA model correct local channel slope (Romero-Diaz et al., 2007). In (Kirkby et al., 2008) and the SPADS model (De Vente et these check dams, infill deposits record historical pulses of al., 2008). In Alatorre et al. (2010), the WATEM/SEDEM sediments produced during discrete flood events after their model is calibrated using the depositional record of the Bara- construction. The coarse texture of the deposited material sona reservoir (NE Spain) and then used for Esera´ River prevents coring, but allows the use of fluvial palaeohydro- catchment sediment yield modelling, providing mean annual logical techniques. The detailed analysis of their alluvial erosion and sediment yield. stratigraphy may provide quantitative information for spe- Not only large reservoirs, such as the Spanish data set cific events, such as the number of events, timing, and de- mentioned above (Avendano˜ Salas et al., 1997), can be used posited volume(s) of an individual flood or floods. Similar for sediment yield estimation, but also smaller reservoirs like techniques have been used in the reconstruction of the magni- check dam reservoirs, irrigation and water supply ponds, etc., tude and frequency of past floods using geological evidence can be in a similar way, a source of information. Verstraeten (Kochel and Baker, 1982; Baker, 2008; Benito et al., 2010; and Poesen (2000) quantify the number of these structures Machado et al., 2011). around the world in a few million dams, with small dams The aim of this paper is to present a new methodology for being defined as retention structures with a storage capacity model calibration and/or validation in catchments with no of between 50 and 5 × 106 m3. This large number of small sediment data availability, by taking advantage of the flood reservoirs in the world is a high potential source of informa- sediment proxy information obtained from check dam in- tion for sediment yield assessment and modelling. Some ex- fills. An existing hydrological and sediment model, the dis- amples of sediment yield studies based on sedimentation vol- tributed TETIS model (Frances´ et al., 2002, 2007; Mon- umes in small reservoirs include McManus and Duck (1985), toya, 2008), is used to illustrate the proposed procedure. Van den Wall Blake (1986), Neil and Mazari (1993), Fos- With this model we aim to reproduce the hydrological and ter and Walling (1994), White et al. (1996), Romero-D´ıaz et sediment regime of a small semi-arid Mediterranean basin al. (2007), Boix-Fayos et al. (2008), Sougnez et al. (2011) (Rambla del Poyo, Valencia, Spain). Downstream-measured and Bellin et al. (2011). Verstraeten and Poesen (2002) cal- water discharge records at a gauge station (with a catch- culated the error on sediment yield estimation for 21 catch- ment area of 184 km2) are employed to calibrate and vali- ments located in central Belgium using small reservoir de- date the hydrological sub-model; the sediment trapped in a posits and concluded that this is a suitable methodology small reservoir, draining a 12.9 km2 upstream subcatchment, for medium-sized catchments (101–104 km2) and for mid- is used to calibrate the sediment sub-model. Time-variable term
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