"Primary effects include conversion of land cover or reversion to an earlier stage of successional development. Both types of change can have cascading effects through ecosystems; however, the long-term effects where forests are allowed to regrow are poorly understood."
What is understood, says Schulte, are the stresses the forest changes are having on wildlife, including birds. Schulte has looked at several species of warblers that have historically inhabited the area. According to her findings, the outlook for them doesn't look good.
"These birds don't have much habitat at present, compared to historical times," she said.
They are also an important and beautiful element of biodiversity, she said. They perform an important function in these forests by eating insects that can become forest pests.
Among natural resource professionals, the forests in the Upper Midwest had been suspected to be changing for some time, according to Schulte, but now there is evidence to support the theories.
"We knew that these kinds of changes had happened," she said. "But this is the first paper to really quantitatively look at it across the entire region. So, anytime you can quantitatively show something, it has a lot more power than simple conjecture."
|Contact: Lisa Schulte|
Iowa State University