Slope Length Factor Research Articles

EROS: A grid-based program for estimating spatially-distributed erosion indices

EROS is a grid-based terrain analysis program for estimating the spatial distribution of soil loss and erosion-and-deposition potential in a catchment. The sediment transport index is similar to the length-slope factor in the Revised Universal Soil Loss Equation, but is applicable to three-dimensional terrain. It characterizes the effects of topography and catchment hydrology on soil loss, and helps to identify areas in a catchment that are highly susceptible to erosion by flowing water. The method is based on characterizing the sediment transport capacity of overland flow using a stream-power approach. The terrain attributes generated by TAPES-G provide the basic terrain attributes used by EROS. Stream networks, subcatchments and the spatial distribution of individual attributes can be plotted interactively or copied to the ARC/INFO geographic information system (GIS) for further analysis and display.

Using rill/interrill comparisons to infer likely responses of erosion to slope length: implications for land management

With the release of the Revised Universal Soil Loss Equation (RUSLE) there is potential to consider a range of responses of erosion to increasing slope length. This paper presents data to illustrate commonly observed effects of increasing overland flow on erosion processes and erosion rates, and considers the application of the data to specifying land management strategies and forms of vegetative cover most suited to particular soils. It also discusses a methodology for assessing relevant slope length factors for the RUSLE based on rill/interrill susceptibility. Three basic responses to slope length are noted: (i) little increase in erosion per unit area with increasing length, due to either the failure of rills to develop for the range of overland flows considered, or rill formation at very low hows with no further increase in erosion rates as flow rates increase; (ii) moderate increase in erosion per unit area with slope length associated with slight rill development; and (iii) large increases in erosion per unit area with slope length as rilling develops strongly. These responses have significance for the relative importance of surface and contact cover (and therefore, for the plant species grown and/or residue management strategy adopted), and for the use of contour banks to reduce slope length.

Combining a modified Universal Soil Loss Equation with a digital terrain model for computing high resolution maps of soil loss resulting from rain wash

Summary Soil loss must be predicted with high resolution for landscape planning in areas of complex toporaphy. In the first part of this paper the length-slope factor LS is differentiated for an application on complex slope geometries, with specific consideration given to catchment convergence and divergence. The result is a differentiated Universal Soil Loss Equation: dUSLE. The second part describes its computational implementation on a surface model, which has the structure of a triangulated irregular network (TIN). The third part shows an example of how this method can be combined with the functions of a geographical information system. This leads to an application of the differentiated USLE, which produces high resolution maps of soil loss by rain fall, if the values of the R-, C-, K- and P-factors are given.

Revised Slope Length Factor for the Universal Soil Loss Equation

ABSTRACT An analysis based on theoretical considerations and data interpretation was used in developing revised relationships for the slope length exponent for the Universal Soil Loss Equation. The analysis was based on the ratio of rill to interrill erosion and resulted in a general relationship between the slope length exponent and slope steepness. Parameters in the relationship are changed depending upon whether the ratio of rill to interrill erosion is expected to be low, moderate or high. Such conditions might be representative of rangeland or no-till seeding, normal seedbed conditions or highly disturbed conditions, respectively. For thawing soil conditions where rill erosion is dominant, an exponent value of 0.5 is recommended..

Soil Erodibility and Slope-length Factors in Soil Loss Prediction of a Farm Land in Japan

Soil Erodibility and Slope-length Factors in Soil Loss Prediction of a Farm Land in Japan