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 the

curve number (CN), which is determined with field information about

soil and cover. Remote sensing was used to establish the soil covers,

while the geographic information system (GIS) allowed to generate a

hydrologic soil group layer and combine data to produce a curve number

map. In Betancí subwatershed the grass covers 85% of the total area

and 83% of soils have a high runoff potential. For this reason, major

part of the ground has a CN between 81 and 86. These conditions make

runoff greater than infiltration and tend to increase the erosion process,

flood and the desertification. As a result, it is recommended to study

evolution term of the curve number and to extend its use to another

areas of the Córdoba department.