A catchment as a simple dynamical system: Characterization by the streamflow component approach

作者：Rusjan Simon^*; Mikos Matjaz

来源：Journal of Hydrology, 2015, 527: 794-808.

DOI：10.1016/j.jhydrol.2015.05.050

• Streamflow recession
• Catchment storage
• Bypassing flow
• Discharge sensitivity function
• Streamwater electrical conductivity
• Hydrograph separation

The simple dynamical system approach was implemented to analyze, explain and simulate streamflow fluxes in diverse seasonal hydrological conditions within the forested Padez stream catchment in SW Slovenia. The catchment is characterized by the flushing, torrential hydrological response conditioned by the flysch geological settings of a low hydraulic conductivity. Consequently, the streamflow formation is not controlled solely by the deeper subsurface catchment storage but is also strongly influenced by the rainfall-runoff that bypasses the deeper subsurface part of the total catchment storage. Therefore, fast component of the streamflow is identified using two-component hydrograph separation; the component recession behavior is described by a separate sensitivity function and used in a simple model to simulate the streamflow. According to the simulation results, the Padez stream catchment behaves primarily like a deeper subsurface storage-dependent system during most of the hydrological conditions. When rainfall intensities increase (rainfall intensities close to 10 mm/h or higher), triggering of the secondary streamflow formation mechanism described by separate, bypassing flow sensitivity function becomes evident and causes fast hydrograph formation with steeply rising and falling limbs. To be able to implement the modeling concept for streamflow predictions, the rainfall losses, most likely associated with interception losses not covered under the potential evapotranspiration calculation, would have to be more thoroughly analyzed through rainfall interception measurements. Our study shows the possible way that two hydrological concepts, the streamflow recession analysis and the two-component hydrograph separation based on relatively easily measurable tracers, such as electrical conductivity, could be combined for analyzing streamflow fluxes.

• 出版日期2015-8