Digital Elevation Model Networks (DEMON): A model of flow over hillslopes for computation of contributing and dispersal areas

Abstract

Current algorithms for computing contributing areas from a rectangular grid digital elevation model (DEM) use the flow-routing model of O'Callaghan and Mark (1984), which has two major restrictions: (1) flow which originates over a twodimensional pixel is treated as a point source (nondimensional) and is projected downslope by a line (one dimensional) (Moore and Grayson, 1991), and (2) the flow direction in each pixel is restricted to eight possibilities. We show that large errors in the computed contributing areas result for any terrain topography: divergent, convergent, or planar. We present a new model, called digital elevation model networks (DEMON), which avoids the above problems by representing flow in two dimensions and directed by aspect. DEMON allows computation of both contributing and dispersal areas. DEMON offers the main advantage of contour-based models (e.g., Moore et al., 1988), the representation of varying flow width over nonplanar topography, while having the convenience of using rectangular grid DEMs.

Characterization of fluvial activity in Parana Valles using different age-dating techniques

“…The original algorithm is called the D8 flow model, but there have been several advances of this model through time that allow better computation of divergent flows on hillslope, such as the D-1 model (Tarboton, 1997) and the Mass Flux Method (Costa-Cabral and Burges, 1994), as well as flow over flat terrain (Garbrecht and Martz, 1997). For simplicity, we only describe the D8 flow model, which determines the flow direction from every grid cell in a DEM by calculating the steepest downhill slope from a grid cell to the eight surrounding grid cells.…”

Massively parallel landscape-evolution modelling using general purpose graphical processing units

“…Alternate routing methods, based upon MFD, have been proposed such as DEMON [18] and D ∞ [19]. The relative merits of these methods were discussed by Erskine [20] and although it is acknowledged that MFD produces more realistic drainage patterns in certain areas, the computational overhead introduced, especially for large DEMs, has seen it largely ignored in favour of the more efficient SFD.…”

Mapping of the Microrelief Structures Using Topographic Data

“…These upper parts are hardly interpretable on topographic maps of 1:10000 scale, which are widely used in land management. The catchment area [1] maps are used to estimate locations of modern streams. However, modern streams are not coincide with the thalwegs of ancient ravines in many cases.…”