New reports show Minnesota's wetlands are in danger
The Minnesota Pollution Control Agency and the Minnesota Department of Natural Resources jointly issued reports on the state's wetlands last week.
Data shows that Minnesota currently has 10.6 million acres of wetlands, which comprise 19.7 percent of the state's land cover, not counting deep lakes and rivers.
In the northeastern region of the state, the majority of pre-settlement wetlands still exist, and a large percentage are in good condition. However, in the western and southern parts of the state, where many wetlands have been lost, those that remain are generally in poor condition.
Plant communities in nearly half of all depressional wetlands, such as marshes and ponds, were shown to be in poor condition, while aquatic macroinvertebrates (such as insects, leeches and snails) fared much better. Certain species of plants and aquatic macroinvertebrates are sensitive to various disturbances, so they are good indicators of a wetland's ecological health or condition.
Wetlands serve a variety of functions, such as providing valuable habitat for wildlife, filtering out pollutants and sediment for the protection of downstream water quality in lakes and streams, and attenuating the impacts of floods by storing water during intense rain storms and snow melt. In addition to downstream benefits, wetlands are important resources in and of themselves.
"Even urban wetlands that look like they have nothing but cattails in them can harbor dozens of species of plants," said Glenn Skuta, MPCA water monitoring manager.
The reports concluded:
-Plant communities are in good condition in only 29 percent of Minnesota's depressional wetlands, while 25 percent are in fair condition and 46 percent are in poor condition.
-Macroinvertebrate communities are in better condition, with estimates of 47 percent good, 33 percent fair, and 20 percent poor.
-Forested wetlands make up 4.4 million acres and are the most common wetland type in Minnesota, followed by emergent wetlands (shallow marshes, wet meadows), shrub swamps, and deep marshes/ponds.
"Even though 10 million acres of wetlands may seem like a lot, Minnesota has lost about half of its wetlands since pre-settlement days," said Doug Norris, wetland program coordinator for the DNR's ecological and water resources division. "Most of the loss has been in the southern and western part of the state. We need to be diligent about protecting what we have left."
The state started the wetland monitoring program in 2006 to assess status and trends of both wetland quantity and quality. Results will allow the agencies to compare future data to reveal trends for wetland quality and quantity. The information will allow the state to begin to understand whether policies, regulations, and incentives are achieving their goals.