Determination of curve number in Betancí subwatershed (Córdoba, Colombia) through remote sensing and GIS

Abstract

The runoff behavior in a watershed can be characterized through thecurve number (CN), which is determined with field information aboutsoil and cover. Remote sensing was used to establish the soil covers,while the geographic information system (GIS) allowed to generate ahydrologic soil group layer and combine data to produce a curve numbermap. In Betancí subwatershed the grass covers 85% of the total areaand 83% of soils have a high runoff potential. For this reason, majorpart of the ground has a CN between 81 and 86. These conditions makerunoff greater than infiltration and tend to increase the erosion process,flood and the desertification. As a result, it is recommended to studyevolution term of the curve number and to extend its use to anotherareas of the Córdoba department.