Submitted to: Applied Engineering in Agriculture
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/12/2009
Publication Date: 4/1/2010
Citation: Norton, L.D., Savabi, M.R. 2010. Evolution of a Linear Variable Intensity Rainfall Simulator for Surface Hydrology and Erosion Studies. Applied Engineering in Agriculture. 26(2)239-245. Interpretive Summary: Erosion of soil is a major problem in the World which threatens food and water supply. To study erosion one can either wait for it to rain or make a machine to simulate natural rainfall. We took historical information from rainfall simulators and made a new one that could more accurately simulate storms that cause erosion and bad water quality in the real World. Our simulator was simple and easy to use and can provide information that researchers need to predict soil erosion for the future. We describe the rainfall simulator in this paper so that other researchers have the option to use this machine to make rain in their research, extension or teaching. The impact of this work is that scientists and engineers are informed of a better and lower cost way to simulate rainfall for their purposes to help solve the problem of soil erosion.
Technical Abstract: Because of dust bowl era wind erosion in the Central USA during the early 1930’s, Congress appropriate funding to study the problem and find ways to protect the land including from water erosion. Afterwards, a series of erosion stations were established across the Eastern USA and natural runoff plots on a wide range of soils, slopes and cropping/management systems, were monitored with natural rainfall. The data collected from these studies served as the basis for developing the Universal Soil Loss Equation (USLE) for rain induced erosion which is still, in revised form, the basis for determining “highly erodible land” for various USDA programs. Because of the expense of maintaining USLE plots and the extreme variability in the research data, they were discontinued and most research since the 1950’s in water erosion has focused on using rainfall simulators to quantify differences in erosion from all the variables of the USLE and refining other parameters. The simulators used over the last 60 years have varied widely in design and functionality and paid little or no attention to the type of water used to conduct the simulation. The objective of this paper is to describe some of the historical development of simulator technology in the USA and describe some recent advances in design that allow them to be used in a wider range of rainfall-runoff and erosion studies. This paper will also describe the most recent portable simulator developed at the National Soil Erosion Research Laboratory.