Using Science to Protect the Mackinaw River

Years of research prove the value of constructed wetlands.

Over 20 years ago, The Nature Conservancy saw something special in central Illinois’ Mackinaw River watershed. This river is teeming with fish and mussels, and its high-quality tributary streams support native and migratory species. In recognition of the watershed’s exceptional value, TNC selected it as a priority conservation site and worked with partners to develop the Mackinaw River Watershed Management Plan in 1998.

At that time, the watershed was facing several stresses: alterations to the river’s hydrology, habitat degradation and reduced water quality. Since 2000, TNC has studied agricultural conservation practices designed to improve water quality, flows and fluctuation patterns. Led by Maria Lemke, director of conservation science for TNC in Illinois, the team examines strategies like grassed waterways, reduced tillage, filter strips, winter cover crops and constructed wetlands.

One of the team’s long-term studies showed the importance of wetlands on farm fields. The findings showed that constructing small wetlands on the edges of fields was incredibly effective at reducing runoff of agricultural pollutants, like nitrogen and phosphorus, into rivers and streams. These wetlands also provide much-needed habitat for many freshwater plants and animals.

The next step is to scale up conservation in the watershed. TNC is developing the Mackinaw River Watershed Greenprint, an online tool designed to document real-time conservation, coordinate efforts,

Choose Native Wildflowers for Solar Arrays

Pollinator-friendly plantings can offer big benefits.

It’s a two-for-one deal: Growing wildflowers and other native prairie plants under and around solar arrays provides a range of environmental benefits, from hosting wildlife to addressing climate change. Native flowering plants can increase pollinator abundance in solar arrays by up to 30% compared with the conventional choice, turfgrass. They can help support species like the endangered rusty patched bumble bee and the iconic monarch butterfly. They also benefit soil and water quality, sequester more carbon and are easier to maintain.

But not all native prairie plants work well; many species grow too tall to fit under the panels. Raising the height of panels can significantly increase planting options and the resulting benefits.

To help land managers figure out the best approach, TNC and Pollinator Partnership created a guide called Greening the Clean Energy Transition: identify new partnership and funding opportunities and ensure that areas of high biodiversity are protected. Caring for freshwater ecosystems, like the Mackinaw River, is part of TNC’s contribution to a global call to protect 30% of the planet by 2030.

Smart Siting and Pollinator-Friendly Solar Energy in Illinois. The guide lays out the benefits of combining pollinator-friendly plantings and solar energy installations, recommends the best species to plant and explains how to prepare and maintain the sites.

Solar energy is taking off in Illinois. New solar could impact up to 320,000 acres across the state by 2050. The new installations will help Illinois reach its goal of a 100% clean energy economy by 2050. Choosing the most appropriate sites for renewables and combining solar with native plantings can ensure that this ramping up occurs in an environmentally friendly manner. Read the guide at nature.org/ilclimate