Applying a probabilistic streamflow model to steep mountain basins focusing on baseflow contribution
Abstract
A probabilistic streamflow model has been successfully used to analyze flow duration curves (FDCs) across a wide range of hydro-climatic regimes. This model was developed by extending soil moisture dynamics which allowed to describe steady-state probability distribution of soil moisture. However, the soil moisture dynamics introduced an assumption that lateral flow contribution can be neglected to simplify the mathematical treatment. This fact indicates that it is difficult to apply the soil moisture dynamics to steep mountain basins because the runoff generation consist of rapid lateral flow through soil or near-surface fractured bedrock and slow flow maintaining baseflow through deep bedrock. On the other hand, baseflow has been separated reasonably in the hydrograph using storage-discharge relationship which can express baseflow recession. Furthermore, the storage-discharge relationship has been integrated in the probabilistic streamflow model. These facts mean that the probabilistic streamflow model has a high affinity for the baseflow separation. In order to analyze baseflow duration curves (BFDCs) in steep mountain basins, we presented how to apply the baseflow separation procedure to the probabilistic streamflow model. The applicability was validated in steep mountain basins in Japan. The analyzed BFDCs fitted successfully the original BFDCs which were obtained to apply the observed hydrograph to the baseflow separation procedure. In addition, the observed FDCs ranging from middle to low parts fitted well the same parts of the analyzed BFDCs, which indicates that the analyzed BFDCs allow to estimate FDCs except rapid flow regime. Finally, we applied the analyzed BFDCs to estimation of water-usage for run-of-river hydropower as a case study.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2019
- Bibcode:
- 2019AGUFM.H13Q1987A
- Keywords:
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- 1847 Modeling;
- HYDROLOGY;
- 1873 Uncertainty assessment;
- HYDROLOGY;
- 1880 Water management;
- HYDROLOGY;
- 1916 Data and information discovery;
- INFORMATICS