Simulation and comparison of stream power in-channel and on the floodplain in a German lowland area

Title:

Simulation and comparison of stream power in-channel and on the floodplain in a German lowland area

Creator:

Song, Song, Schmalz, Britta, and Fohrer, Nicola

Identifier:

https://cdk.lib.cas.cz/client/handle/uuid:09a78152-ad1e-4d38-a4c2-a7736e70772d
uuid:09a78152-ad1e-4d38-a4c2-a7736e70772d
doi:10.2478/johh-2014-0018

Subject:

HEC-RAS model, in-channel flow, floodplain flow, unit stream power, and inundation area

Type:

model:article and TEXT

Format:

bez média and svazek

Description:

Extensive lowland floodplains cover substantial parts of the glacially formed landscape of Northern Germany. Stream power is recognized as a force of formation and development of the river morphology and an interaction system between channel and floodplain. In order to understand the effects of the river power and flood power, HEC-RAS models were set up for ten river sections in the Upper Stör catchment, based on a 1 m digital elevation model and field data, sampled during a moderate water level period (September, 2011), flood season (January, 2012) and dry season (April, 2012). The models were proven to be highly efficient and accurate through the seasonal roughness modification. The coefficients of determination (R2 ) of the calibrated models were 0.90, 0.90, 0.93 and 0.95 respectively. Combined with the continuous and long-term data support from SWAT model, the stream power both in-channel and on the floodplain was analysed. Results show that the 10-year-averaged discharge and unit stream power were around 1/3 of bankfull discharge and unit power, and the 10-year-peak discharge and unit stream power were nearly 1.6 times the bankfull conditions. Unit stream power was proportional to the increase of stream discharge, while the increase rate of unit in-channel stream power was 3 times higher than that of unit stream power on the floodplain. Finally, the distribution of the hydraulic parameters under 10-years-peak discharge conditions was shown, indicating that only 1-10% of flow stream was generated by floodplain flow, but 40-75% volume of water was located on the floodplain. The variation of the increasing rate of the stream power was dominated by the local roughness height, while the stream power distributed on the floodplain mainly depended on the local slope of the sub-catchment.

Language:

Slovak

Rights:

http://creativecommons.org/licenses/by-nc-sa/4.0/
policy:public

Coverage:

133-144

Source:

Journal of hydrology and hydromechanics | 2014 Volume:62 | Number:2

Harvested from:

CDK

Metadata only:

false