Predictions in Ungauged Basins: Promise and Progress (Proceedings of symposium S7 held during the Seventh IAHS Scientific Assembly at Foz do Iguaçu, Brazil, April 2005). IAHS Publ. 303, 2006, 342-350.


 

Effects of conservation tillage on storm flow: a model-based assessment for a mesoscale watershed in Germany

 

INGO HAAG, ANNETTE LUCE & KAI GERLINGER

Dr.-Ing. Karl Ludwig, Consulting Engineers, Herrenstr. 14, D-76133 Karlsruhe, Germany

ingo.haag@ludwig-wawi.de

 

Abstract The hydrological model LARSIM was used to assess the flood miti­gating effect of conservation tillage within the 195-km2 loess covered water­shed of the River Glems, Germany. In order to adequately account for the effect of conservation tillage on the infiltration process and the formation of infiltration-excess overland flow, LARSIM was extended by an infiltration module. The new module was parameterized with the results of small-scale field studies, enabling one to upscale these results to the watershed scale. Modelling scenarios for River Glems show that only the peak discharges of floods caused by convective rain events of high intensity are mitigated by introducing conservation tillage. Since most floods in the mesoscale watershed are caused by advective precipitation events of moderate intensity, the overall effect of conservation tillage on peak discharges of given return periods is negligible.

 

Key words  flood mitigation; hydrological model; infiltration-excess; land-use scenario; LARSIM; loess soil; River Glems; runoff generation; soil management practice