Influence of land cover data sources on estimation of direct runoff according to SCS-CN and modified SME methods.

Abstract The aim of this work was to assess the accuracy of direct runoff depth calculated according to an original Soil Conservation Service – Curve Number (SCS-CN) method and a modified Sahu - Mishra - Eldho (SME) method based on different sources of information on land cover. Main novelty of this work is using Database of topographic objects (BDOT10k) instead of Corine Land Cover (CLC) for the assessment of land cover in a catchment. The research was performed in the Kamienica river, a right tributary of the Dunajec, Poland. The effect of land cover data on runoff depth was assessed with the original SCS-CN method, and modified SME method. The value of CN parameter was estimated using two databases on land use, CLC and BDOT10k. BDOT10k was proven to be a considerably more precise land cover database that enabled more accurate interpretation. The study demonstrated the highest accuracy of direct runoff calculation with SME-CN method, irrespective of the approach used for determination of the catchment land use. The use of SME-CN instead of the original SCS-CN method provides much more accurate prediction of direct runoff in a catchment. Highlights • BDOT10k should be used to determine a catchment land cover for smaller map scales. • Differences in CN according to BDOT10k or CLC were minor for large-scale maps. • Modified SME-CN model provided an accurate estimation of direct. [ABSTRACT FROM AUTHOR]