This paper describes methods that use digital elevation models (DEMs) in hydrology, implemented as an ArcGIS toolbar using Visual Basic and the ESRI object library. I describe generalized channel network delineation to objectively estimate drainage density and by using terrain curvature accommodate spatially variable drainage density. The multiple flow direction field determined from a DEM also...

A major challenge in runoff and soil erosion modelling is the adequate representation of most relevant processes models while avoiding over parameterization. In European loess belt, progressive crusting during rainfall events, resulting infiltration-excess runoff, usually considered dominant process generating on catchments covered with silty soils. Saturation-excess may also occur affect their...

Full coupling of physical processes, natural numerical coupling, and parsimonious but accurate data coupling are three key steps in efficient and accurate simulation of distributed hydrologic states in watersheds. Here we present a physically-based, spatially distributed hydrologic model (called PIHM) that utilizes all the three coupling strategies. Interception, snow melt, transpiration, evapo...

Data collected at two measurement scales from a semiarid grassland are presented and analyzed to explore the hydrologic effects of grazing, interactions between overland flow and infiltration, and scale issues. Rainfall-runoff simulations were used to quantify the areal ~3 by 10 m plot scale! response, and small-diameter ~9 cm! disk infiltrometers were used to estimate point-scale hydraulic con...

The relationship between landuse/landcover (LULC) changes and land degradation in two Mediterranean sites is investigated using remotely sensed and ancillary data. The areas of study, the Xaló river catchment in the north of the Alicante province in southeast Spain and the Aegean island of Lesbos, Greece, have both been subjected to changes in LULC, such as abandonment, overgrazing, forest fire...

Forestry operations can significantly alter hydrological and erosional processes in a catchment. In the course of developing timberland, a network of persistent roads and skid trails causing soil compaction is usually established. Hereby, the infiltration rate of the soil is distinctly reduced, which leads to the generation of overland flow—this may also cause soil erosion. In this study, a sma...