Leopold Center work helped set stage for new Iowa wetlands program
By Laura Miller
Newsletter Editor
When ISU botanists Bill Crumpton and Arnold van der Valk asked the Leopold Center for $57,000 in 1989 to build experimental mini-wetlands next to a crop field north of Ames, they had no idea what they would discover.
They needed some way to study what happened to agricultural pesticides and nutrients after they entered a wetland. They proposed construction of wetland mesocosms -- a cutting-edge research method at the time -- that allowed them to take measurements in a complex system under controlled but realistic conditions. Each mesocosm consisted of a 12 ft. diameter plastic tank buried 2 ft. in the ground, filled with natural wetland soil and cattails, and connected to equipment to take periodic measurements.
The Leopold Center approved funds to build 36 mesocosms. Crumpton and van der Valk also received two Leopold Center competitive grants to begin work at the new facility.
As it turned out, they were correct in their assumptions. Wetlands are part of nature's own system of handling water pollutants. Eventually, other research would show that a marsh located in the right place in a watershed could remove 40 to 70 percent of nitrate contained within agricultural drainage water.
The Leopold Center-funded mesocosms laid the groundwork for other research. In 1992, Crumpton, van der Valk and ISU animal ecologist Gary Atchison secured more than $500,000 from the Environmental Protection Agency (EPA) for wetlands water quality work. Several years later, Crumpton began working with ISU agricultural and biosystems engineer Jim Baker on an expanded project that included the Iowa Department of Agriculture and Land Stewardship (IDALS) as a cooperator. That project became part of a long-term IDALS water quality program that has funded more than $500,000 of wetlands research projects since 1994.
Results from these projects and other watershed-scale research have been used to create a new $38 million Iowa program, the Conservation Reserve Enhancement Program (CREP). The goal of the program, which uses state and federal funding, is to build nitrate-cleansing wetlands in targeted areas of Iowa. Construction of the first wetland -- on a farm in Dallas County -- was announced October 31 by Iowa Agriculture Secretary Patty Judge and Derryl McClaren, state director of the U.S. Department of Agricultures Farm Service Agency.
Tom Isenhart, who helped monitor the mini-wetlands as Crumpton's graduate student, now coordinates CREP activities for IDALS.
CREP is a partnership between IDALS and the U.S. Department of Agriculture. An important part of CREP is building wetlands in the proper place in the watershed. To date, CREP has identified more than 150 possible sites in 37 targeted counties. How quickly the wetlands will be built depends on landowners, and availability of funds. IDALs also is providing funds for Crumpton's research group to monitor the effectiveness of the CREP wetlands.
The first CREP project is in the Beaver Creek watershed, a tributary to the Des Moines River, which provides much of the drinking water for the city of Des Moines that operates the world's largest nitrate-removal system. The 57-acre project includes a 15-acre wetland and buffers south of Woodward on an acreage owned by Darrell Hughes.
"The mesocosm facility still is one of the best wetlands research sites around," said Crumpton, whose work continues under a variety of sponsors. "It was a good investment just about any way you want to look at it. The facility made us competitive so that we could be considered for other major sources of funds, but more importantly, Leopold Center funds were the seed money that led to important new lines of research."
One mosquito, two mosquito, three mosquito, more??
A legitimate question, especially with the advance of West Nile Virus, is whether creating wetlands will further encourage mosquito breeding, potentially increasing disease risks where the mosquito is a vector. We recommend two publications, available on the web, for readers who want to further investigate interactions of wetland ecologies and mosquitoes. -- from the Leopold Center staff
- Did you know?...Healthy Wetlands Devour Mosquitoes (pdf format).
- Mosquitos in Constructed Wetlands: A Management Bugaboo? (pdf format).