WEPP: A new generation of erosion prediction technology

EROSION prediction is the most widely used and most effective tool for soil conservation planning and design in the United States. Because it is impossible to monitor the influence of every farm and ranch management practice in all ecosystems under all weather conditions, erosion predictions are used to rank alternative practices with regard to their likely impact on erosion. These erosion predictions are thus an essential part of soil conservation programs in the United States. The prediction of soil erosion by water has played an important role in the use, management, and assessment of land, not only in the United States, but in most regions of the world. The major tool has been the universal soil loss equation (USLE) developed by Wischmeier and Smith ( 10, 11 ). USLE is a fixtor-based equation. The soil erosion process is quantified and approximated by a series of factors. Each factor may quantify one or more processes and their interactions. The equation has served and continues to serve our needs in erosion prediction well. However, like most tech- nology that is at least 30 years old-with components that are similar to those derived nearly 50 years ago-there are some short- comings. As …