Nature center offers lesson in karst

Published 12:00 am Friday, March 2, 2001

Education in a trunk was unveiled this week at the J.

Friday, March 02, 2001

Education in a trunk was unveiled this week at the J.C. Hormel Nature Center.

Email newsletter signup

The subject is karst and how it impacts on the area’s water supply and water quality.

Karst in a trunk brings the subject closer than karst in a cave.

Warren Netherton, the Minnesota Department of Natural Resources manager at Mystery Cave in Fillmore County, can show visitors just what karst is during an underground trek.

However, classroom teachers have a hard time translating the importance of karst in their earth science classes.

For instance, consider a brief primer on karst.

Karst is a type of landscape that forms over limestone and other soluble rocks. The word comes from the Germanized version of the Slovenian word "kras," meaning a dry, waterless place.

Karst landscapes are characterized by solution or the dissolving of the underlying rock. Rainwater moves through the soil, takes up carbon dioxide and becomes a weak carbonic acid solution.

In turn, rocks, such as limestone, dolomite and gypsum, dissolve.

Typically, the line between the groundwater and surface water blurs. They are closed depressions or sinkholes and blind valleys, water skins underground and surface drainage is disrupted, caves occur and there is rapid flow of groundwater.

Jeffrey Green and E. Calvin Alexander, Jr., reported on karst in Mower County for the Minnesota Geological Survey.

Their findings showed Mower County is entirely underlain by karst, and while it is literally everywhere, the LeRoy area may be considered the karst capital of the county.

More than 300 sinkholes have been inventoried in the county. Some of the karst-created sinkholes are large, some are very small and some are still developing.

According to the findings by Green and Alexander, Mower County has three significant karsts, which have important ground water resources that are vulnerable to contamination. This, Green and Alexander, said mandates that karst aquifer protection is a top priority for citizens and government in Mower County.

The unique learning trunk as well as a far-ranging display at the Ruby Rupner Auditorium on the grounds of the J.C. Hormel Nature Center will help convey that message and to educate area students and the public about the impact karst has on water quality.

Larry Dolphin, director and naturalist at the nature center, welcomed 36 teachers and other participants to Monday’s workshop.

Green was the keynote speaker. Other presenters during the day-long workshop kept the teachers busy.

Bea Hoffman of the Southeast Minnesota Water Resources Board introduced participants to the giant karst display and told how it could be used in educational activities.

Jim Heintzman of the Minnesota Science Museum literally opened the karst learning trunk, one of 12 trunks which examine different topics of interest and are made available throughout Minnesota to teachers and others.

The karst display will be open to the public, during regular nature center visitor hours. Ellis Middle School students will assist the curious in understanding through the hands-on activities how important karst is the water quality.

Among teachers from 12 different school districts in a nine-county area at Monday’s workshop were Kathy Huffman and Cheryl Dunlap, who both said the self-contained karst learning trunk will be an invaluable to earth science educators.

"The karst model will be so helpful," said Dunlap, an eighth-grade science teacher. "It such an abstract subject for middle school students, but these materials and the display will help so much to clarify it."

Huffman, a sixth-grade science teacher, said, "It’s really hard to find resource materials to teach about water quality and groundwater and other aspects like that of earth sciences, but the learning trunk puts all of that in one place."

Lynn Brigham, a Lyle Public Schools science teacher, called the display and learning trunk "valuable tools for teachers."

"Anyone teaching earth science knows how hard it is to find the necessary materials," Brigham said. "Now, this will help me a lot, because it is about a topical subject and something they can relate to in Mower County."

Heintzman, an education resources manager for the Minnesota Science Museum and a former college classmate of Dolphin’s, said the development team responsible for the display and learning trunk had teachers in mind when they went to work.

"We wanted it to be educational, but we wanted it to be more informal and have all the components they would need," he said.

With specific hands-on activities and an "operator’s manual," Heintzman expects the learning trunks program to beckon a new audience to science, while stimulating the currently curious.

As far as the area’s earth science teachers go, they hope the karst display and learning trunk will help them get to the bottom of the fascinating mystery.