March 12, 2008
North Mankato, Minn. - Students attending the 2008 Children's Water Festival at South Central College in North Mankato got a first hand look at how different coverage of soils can have a dramatic impact on the amount of erosion taking place on farm fields. Minnesota Department of Agriculture (MDA) Sustainable Agriculture Specialist Mark Zumwinkle demonstrated the department's rainfall simulator to several hundred fourth graders at the event on March 12. The simulator is designed to mimic a natural rainstorm on three different types of soil conditions: bare soil, soil with a cover-crop and soil covered with woodchip mulch. Students were able to observe the amount of runoff, soil splash and erosion on each type of soil.
The MDA also has a larger version of the rainfall simulator it uses to assist farmers, researchers, extension, and state agency staff with designing and implementing on-site farm research to study the interaction of rainfall and various tillage systems, including water retention, runoff, etc. Simulated rainfall is a primary tool used on farms to assess tillage management effects on soil and water quality.