Evaluating the effect of land cover, seasonality and delineation method on runoff at the watershed scale

Seventeen watersheds with varying land covers were delineated using three methods. The delineation methods differ in how the watershed's internal drainage is evaluated. Runoff estimates from storms for spring, summer, and fall were compared to observed to corresponding runoff from USGS gaging station data. Watersheds were categorized by their dominant land cover (agriculture, forest, or urban). The greatest differences between observed and estimated data were found in agriculture and urban especially spring versus fall for all delineations. Forest land cover was found to have no seasonal difference for all three delineation methods. This work contributes to the growing body of research demonstrating that vegetative seasonal differences have a greater impact on runoff than is accounted for in the model