|Morgan, R.P.C. - CRANFIELD UNIVERSITY|
Submitted to: European Soil Conservation Society
Publication Type: Proceedings
Publication Acceptance Date: March 21, 2000
Publication Date: N/A
Interpretive Summary: This is a review paper on the subject of soil erosion models. Erosion models are used for purposes of designing conservation practices, helping to choose between conservation alternatives, making erosion surveys of regional and national scale areas, and for design of engineering projects. This paper reviews the types of erosion models used and describes two models is detail. Applications and limitations of erosion models are also presented. The paper will give the potential user of erosion models a quick overview of the state of the art of erosion prediction technology. The impact of this paper will be better and more efficient development of conservation and engineering plans in the future, which will result in a savings in the world's soil resource as well as investment capital. As an example, an engineering team might read this paper to decide what type of model to best use to evaluate soil erosion rates in the construction of a new reservoir, as well as to design conservation practices in the contributing watershed so as to prevent siltation and to lengthen the useful lifespan of the reservoir.
Technical Abstract: Soil erosion models can play a critical role in addressing problems associated with soil protection and conservation. They are used for assessment and inventory purposes when financial and time-costs of obtaining useful soil erosion measurements are prohibitive. They provide assessments of both on-site loss of topsoil and off-site delivery of sediments from fields and catchments. Thus they have value for addressing both declining soil productivity on agricultural lands and problems associated with non-point source pollution. Models are used for purposes of conservation planning, primarily for selecting from a range of options the most appropriate conservation measures for a particular field or geographical region. Models also are used with increasing frequency by governmental agencies at all levels to set regulations for erosion control practices for agriculture, construction, and forestry operations. Finally, models are used to increase and synthesize our knowledge of soil erosion and conservation science. In this paper we discuss and contrast the two principal classifications of soil erosion models, empirical and process-based, and present two of the newer process-based erosion models, EUROSEM and WEPP. The concepts behind the models are briefly discussed and examples are provided of their use in practice. In an assessment of their performance to date, guidelines are presented to model users regarding good and bad practice with respect to their application. The need to recognize and deal with problems of data and model uncertainty provides some challenges for the future that will enhance the value of process-based models to users.