The Curve Number (CN) rainfall–runoff model is a widely used method for estimating the amount of rainfall and runoff, but its accuracy in predicting runoff has been questioned globally due to failure produce precise predictions. was developed by United States Department Agriculture (USDA) Soil Conservation Services (SCS) 1954, data documentation about development are incomplete, making it diffi...

nowadays protecting land cover, quality and quantity of water resources are important. surface runoff is one of most important reasons of soil erosion which causes sediment in reservoirs and reduction of land’s fertility and also quality reduction water of rivers. so the main issue is exact prediction of basin runoff to raining events. the hydrologic models are simplified models of real hydrolo...

The Rational method was reviewed, and found to be a special case of the kinematic wave solution under a uniform rainfall excess. In this study, a moving average procedure is introduced to the kinematic wave model. The kinematic wave solution is modified from an instantaneous rainfall to an average rainfall over a period of time of concentration. The revised kinematic wave solution provides the ...

[1] The O/O ratio of snowmelt from a seasonal snowpack typically increases with time as the melting process progresses. This temporal evolution is caused by isotopic exchange between liquid and ice as meltwater percolates down the snow column. Consequently, hydrograph separations of spring runoff using the bulk snow composition as the new water end-member will be erroneous. Accurate determinati...

It is often assumed that stable water isotopes (dD and d18O) provide redundant information for a given sample of water. In this note we illustrate that the choice of isotope used may influence the resultant hydrograph separation. This is especially true in light of the spatial and temporal variability in the isotopic composition of rainfall water at the catchment scale. We present several possi...

[1] This study investigated how roads interact with hillslope flow in a steep, forested landscape dominated by subsurface flow and how road interactions with hillslope flow paths influence hydrologic response during storms in a second-order catchment. Runoff was measured continuously from 12 subcatchments draining to road segments and covering 14% of a 101-ha, second-order catchment (WS3) in th...