Runoff is the amount of water flux over the surface or sub-surface. It can be measured in a gauged watershed or estimated using model. There are many modes to calculate runoff. One of them is Curve Number-NRCS. One advantaged to use CN is that it considers the major runoff-producing watershed properties like: land use, surface condition, antecedent moisture condition and land use.

It is important to monitor the soil loss, catchment water balance and the erosion extent

Hello Dear Eunice

Thanks from your answer. it is useful for me.

Dear Rakesh

Thanks

Simply speaking, runoff production is equivalent to water yield or effective rainfall in the rainfall-runoff relationship or the runoff cycle process. So method of estimation can use classic hydrol analysis substracting interception, infiltration and evapotranspiration from gross rainfall. More direct estimate is as represented by runoff coefficient.