TY  - JOUR
A1  - Bronstert, Axel
A1  - de Araujo, Jose-Carlos
A1  - Batalla  Villanueva, Ramon J.
A1  - Costa, Alexandre Cunha
A1  - Delgado, José Miguel Martins
A1  - Francke, Till
A1  - Förster, Saskia
A1  - Guentner, Andreas
A1  - Lopez-Tarazon, José Andrés
A1  - Mamede, George Leite
A1  - Medeiros, Pedro Henrique Augusto
A1  - Mueller, Eva
A1  - Vericat, Damia
T1  - Process-based modelling of erosion, sediment transport and reservoir siltation in mesoscale semi-arid catchments
T2  - Journal of soils and sediments : protection, risk assessment and remediation
N2  - To support scientifically sound water management in dryland environments a modelling system has been developed for the quantitative assessment of water and sediment fluxes in catchments, transport in the river system, and retention in reservoirs. The spatial scale of interest is the mesoscale because this is the scale most relevant for management of water and land resources.
 This modelling system comprises process-oriented hydrological components tailored for dryland characteristics coupled with components comprising hillslope erosion, sediment transport and reservoir deposition processes. The spatial discretization is hierarchically designed according to a multi-scale concept to account for particular relevant process scales. The non-linear and partly intermittent run-off generation and sediment dynamics are dealt with by accounting for connectivity phenomena at the intersections of landscape compartments. The modelling system has been developed by means of data from nested research catchments in NE-Spain and in NE-Brazil.
 In the semi-arid NE of Brazil sediment retention along the topography is the main process for sediment retention at all scales, i.e. the sediment delivery is transport limited. This kind of deposition retains roughly 50 to 60 % of eroded sediment, maintaining a similar deposition proportion in all spatial scales investigated. On the other hand, the sediment retained in reservoirs is clearly related to the scale, increasing with catchment area. With increasing area, there are more reservoirs, increasing the possibility of deposition. Furthermore, the area increase also promotes an increase in flow volume, favouring the construction of larger reservoirs, which generally overflow less frequently and retain higher sediment fractions. The second example comprises a highly dynamic Mediterranean catchment in NE-Spain with nested sub-catchments and reveals the full dynamics of hydrological, erosion and deposition features. The run-off modelling performed well with only some overestimation during low-flow periods due to the neglect of water losses along the river. The simulated peaks in sediment flux are reproduced well, while low-flow sediment transport is less well captured, due to the disregard of sediment remobilization in the riverbed during low flow.
 This combined observation and modelling study deepened the understanding of hydro-sedimentological systems characterized by flashy run-off generation and by erosion and sediment transport pulses through the different landscape compartments. The connectivity between the different landscape compartments plays a very relevant role, regarding both the total mass of water and sediment transport and the transport time through the catchment.
KW  - Connectivity
KW  - Deposition
KW  - Erosion
KW  - Modelling
KW  - Sediment transfer
KW  - Semi-arid
Y1  - 2014
UR  - https://publishup.uni-potsdam.de/frontdoor/index/index/docId/37371
SN  - 1439-0108
SN  - 1614-7480
VL  - 14
IS  - 12
SP  - 2001
EP  - 2018
PB  - Springer
CY  - Heidelberg
ER  -