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North Temperate Lakes Long-Term Ecological Research Site

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LTER: Comparative Study of a Suite of Lakes in Wisconsin  (University of Wisconsin-Madison)

Research Focus

Scientists at the North Temperate Lakes Long-Term Ecological Research (LTER) site are interested in how the environment, climate and changing land use and cover interact to shape lake characteristics and dynamics over time.

The North Temperate Lakes LTER primary study sites include a set of seven northern Wisconsin and four southern Wisconsin lakes and their landscapes. The lakes are located from high to low in forested, agricultural, and urban catchment landscapes.

Through a broad range of research activities, the program seeks to gain a predictive understanding of lake ecology at longer and broader scales than has been traditional in limnology, the study of lakes. Thus, the North Temperate Lakes LTER analyzes and interprets data from suites of lakes collected over long periods. Its research program is interdisciplinary and aims to understand the ecology of lakes in relation to relevant atmospheric, geochemical, landscape and human processes.

NTL-LTER supports two field stations, the Hasler Laboratory of Limnology on Lake Mendota in the Yahara Lake District of southern Wisconsin and the Trout Lake Station in the Northern Highlands of Wisconsin. Most of the data collected are public, available online, and date to 1981 when NTL-LTER became one of NSF's first six LTER sites.

The project is administered by the Center for Limnology at the University of Wisconsin-Madison.

Research Outcomes

The North Temperate Lakes LTER developed the concept of "lake landscape position" – how a lake’s location within the larger landscape provides a basis for understanding lake characteristics and dynamics. This concept is a powerful tool for forecasting how and why lakes will respond differently to changes in land use and climate or to invasive species and other disturbances.  It also frees policymakers from having to use "one size fits all" management policies for lakes.

North Temperate Lakes LTER scientists also provided the first experimental evidence that radical change in an ecosystem can be detected in advance, possibly in time to prevent ecological catastrophe. In other research, synthesis of long-term records of lake and river ice duration throughout the Northern Hemisphere provided evidence that freshwater ecosystems are responding to climate change over the past 150 years.

Education & Outreach

The Northern Temperate Lakes LTER Partnerships with Schools: NTL-LTER establishes long-term relationships with schools and districts in Wisconsin. The LTER and the Center for Biology Education at the University of Wisconsin Madison have collaborated since 1998 on outreach and education.

It partners with schools in the Arbor-Vitae Woodruff area of northern Wisconsin near its Trout Lake Field Station. Scientists and other staff members at the field station work with elementary and middle school teachers to involve students in winter activities that introduce students to scientists, LTER research done in their area, biological diversity and limnological methods. The Trout Lake Field Station also hosts Research Experiences for Teachers participants.

LTER-school partnerships in southern Wisconsin include workshops and courses for K-12 teachers, precollege activities for K-12 students and research experiences for teachers.

The site has also partnered with science education reform research projects in Wisconsin, California, and Tennessee. Researchers collaborated with K-12 teachers in the Verona school district to help children develop their understanding of ecology.

Professional Development Resources and Instructional Materials for Students: The North Temperate Lakes LTER partnerships with schools have led to new educational materials for teacher professional development and instructional materials for students. 

Research Experiences for Teachers: NTL-LTER scientists at the Trout Lake Biological Field Station and at UW-Madison routinely host teachers in their research group. Research Experiences for Teachers participants typically spend part of their summer actively conducting research and developing instructional materials related to their research, followed by academic year field-testing in their schools.



Images (1 of )

  • painting, fish in foreground and ghostly fish in background
  • photo in quadrants of lake bottom stripped of most life forms
  • photo in quadrants showing lake bottom with vegetative life
The school of walleyes in this painting by Melinda Schnell is fading away as the rainbow smelt increase in numbers. It was part of an exhibit titled "Drawing Water: Artists and Scientists Explore Northern Lakes"
M. Schnell; UW-Madison
Sparkling Lake, Wis., before removal of invasive rusty crayfish.
Steve Carpenter, University of Wisconsin-Madison
Sparkling Lake, Wis., after the removal of rusty crayfish, an invasive species, from its waters.
Steve Carpenter, University of Wisconsin-Madison