… Some Ugly Truth Revealed
Written by Dr. Richard Cruse, Director of the Iowa Water Center and Professor in Agronomy at Iowa State University
Answering a speaking request from the Nebraska Natural Resource Districts, I delivered a talk last week in Central Nebraska. Kearney, Nebraska to be more exact. Kearney is located deep into the irrigated area of the Great Plains, and so I wondered a little – actually more than a little – why this group would be interested in my focus area of soil erosion. More specifically, why they would be interested in hearing about a project that I am working on that is called, The Daily Erosion Project.
The Daily Erosion Project is a tool that utilizes multiple data sources to estimate soil movement and water runoff from hill slopes on a daily basis. Currently, this tool models soil erosion across approximately 1600 small watersheds that geographically form the State of Iowa. The development and expansion of this tool is coming to other regions of the Midwest, such as Minnesota, Kansas, Wisconsin, and Eastern Nebraska.
Why would anyone be interested in this information? Healthy and abundant soils lead to healthy and abundant crops. Our ever-increasing loss of topsoil reduces crop yield potential, and in times of drought, this becomes more and more evident. As we’ve seen throughout history, societies without quality soils tend to have short histories.
Soil erosion also contributes to our surface water quality problems. Eroded sediments fill reservoirs and floodplains. This not only damages our built environment, but also disrupts ecological habitats in our water systems. Solutions to this include removing sediment from ditches – or dredging – at a significant cost to the taxpayer.
Soil loss also comes at a cost to the farmer. Lost sediment from farm fields carry nutrients that have been valued at more than $2.50 per ton of lost soil. The average hillslope soil loss rate of Iowa is about 5.8 tons per acre per year, with some watersheds averaging over 30 tons per acre per year. Soil erosion costs!
Soil erosion can be minimized with a three-pronged approach to managing the issue. Farmers and landowners across the US Corn Belt Region can: (1) seek to understand the cost or impact of inappropriate management, (2) learn how the right soil management practices can pay dividends, and (3) use the soil management practices that are well-suited for their operation.
Targeting limited financial resources to assist with land management improvement in the areas of most need and/or most vulnerable has merit and just makes good economic sense. Data driven soil erosion estimates, such as those generated by the Daily Erosion Project, can provide the foundation for informed policy and good, everyday practices on farmland across the Midwest.
Now, back to Nebraska.
Areas of Nebraska have recently experienced periodic rainfalls of five or more inches of rain. This is occurring more frequently in recent years than it did in the past. Similar rainfall experiences exist for Iowa and surrounding states. People from around the corners of the Midwest are coming to acknowledge that our land is not immune to the extreme weather events that we have been experiencing from year-to-year. Some watershed-level soil erosion estimates during storm filled years in Iowa have even exceeded 40 tons per acre – in a single year.
The Nebraska Natural Resources District seems to get it. They were energetic, highly engaged, and rich with questions. A good and very important question from the group was: Can the Daily Erosion Project be used to test scenarios of different management practices? Currently, the tool is being developed to run different scenarios with a variety of in-field conservation practices, such as extended crop rotations and conservation tillage practices. Using the Daily Erosion Project in this way is the next step to not only place data in the hands of farmers, but to also help them make better management decisions on their land.
We can do better; we must do better. By getting tools, such as the Daily Erosion Project, in the hands of the public we now have the ability to do better. It’s another tool in the toolbox that the public can use to help make better decisions. Nebraskans get it and others must, too.