Due in part to its historical industrial base, the St. Louis Metro East region, and the greater St. Louis region in general, has had significant historical issues with air quality. Overall air quality is better today than what it was at the beginning of the 20th century. However, work still needs to be done to reduce man-made ozone, as well as fine particulate matter, such as that coming from exhaust smoke, which threatens the health of residents within the region. For more information on air quality in Illinois and the Metro East, please visit: http://www.epa.state.il.us/air/air-quality-menu.html
Illinois contains some of the most highly productive soils in the world and southwestern Illinois is no exception. Approximately 800,000 acres in agriculture are listed as prime farmland, (recognized by USDA as land that has the best physical and chemical characteristics for producing food, feed, forage, fiber and is available for these uses), and another 400,000 acres are listed as soils of statewide importance (determined by the state and nearly meet the qualifications of prime farmland). This acreage is important in the production of corn and soybeans. Washington County also boasts the largest winter wheat harvest in the State of Illinois. Much of the world's supply of horseradish is produced in the Collinsville area, due in part to the high potash content within the soils.
Kaskaskia River Corridor:
Running northeast to southwest for a total of 325 miles the Kaskaskia River corridor is a significant migratory and ecological corridor within the state. Of the 59 animal species found in Illinois, 83% reside within the watershed. For reptiles, 60% of the species are represented in the basin. Vascular plants total about 1,100 species in the basin, or 40% of those in Illinois. Of the bird species found in Illinois, 287, or an amazing 96% are found here (including migrants).
The largest bottomland, hardwood forest within Illinois, at 43,000 acres, is located along the Kaskaskia between Carlyle Lake & Fayetteville. One tract within this forest is the single largest contiguous tract in Illinois (7,300 acres) and is approximately two miles wide at certain points. These dense forest blocks are especially important to neotropical songbirds that visit here from Central and South America.
Post oak flatwoods, also known as southern flatwoods, once covered 1.5 million acres in the southern one-third of Illinois, before European settlement. This region of the state, defined in the Natural Divisions of Illinois as the Southern Till Plain, is the world's primary home of the post oak flatwoods community. Today, however, this community type continues to disappear. The Illinois Natural Areas Inventory, (INAI), found that only 658 acres of high quality post oak flatwoods remain in all of Illinois. This amounts to little more than .0004 percent of the original post oak flatwoods landscape that existed in Illinois 200 years ago. A majority of the remaining high quality southern flatwoods are located in the southwestern Illinois counties of Clinton, St. Clair and Washington. Relatively few acres are permanently protected.
The karst topography, located in portions of Madison, Monroe, Randolph and St. Clair Counties contains an estimated 10,000 sinkholes, with as many as 230 per square mile. There are a total of 142 known caves within this region, the largest being Illinois Caverns. These caves are the only place in the world where the Illinois cave amphipod, a small cave-dwelling crustacean, is found.
There are several Illinois Natural Area Inventory sites in the bluff corridor between Dupo and Prairie du Rocher that contain prairie complexes. Many of these sites remain today due to the steep slopes preventing their conversion for agricultural purposes. Invasive plant species, including red cedar and bush honeysuckle are actively taking over these sites, leading to the loss of four identified Illinois Natural Area Inventory sites since 1976. Without active resource management many more sites will be lost over the next decade.
American Bottom Ecosystem:
The area which lies east of the Mississippi River to the limestone bluffs from Alton south to the mouth of the Kaskaskia River is commonly referred to the American Bottom ecosystem. This area once contained undulating ridges and swales offering a variety of habitat types, including wide bottomland forested corridors and up to 35% wetlands. Since urbanization of this region occurred, much of this land has been levied, drained, leveled and otherwise modified in such a manner that little high-quality native habitat remains.
Southwestern Illinois contains a wealth of water resources, including the Mississippi River, the Kaskaskia River, and Carlyle Lake, the largest man-made lake in the State of Illinois. There are also approximately 200,000 acres recorded as "wetlands" within the region. These resources are truly multi-functional, offering opportunities for drinking water, recreation, industry, agriculture and navigation. While our water resources are considered as assets, many of these resources possess some level of contamination. The seven county Metro East region contains approximately 26,000 surface acres of impaired lakes. Carlyle Lake alone makes up nearly 85% of this total. Pollutants include remnants of pesticides and herbicides that have now been banned or are heavily regulated, as well as elements such as phosphorus, manganese, and zinc. Another issue affecting the region's lakes is aquatic algal blooms from high nutrient deposition leading to lower dissolved oxygen levels. Sources of these pollutants include urban storm sewer runoff, agricultural practices including crop production and animal feeding operations, industrial point discharge, recreational pollution sources and on site waste treatment systems.
There are also approximately 800 miles of impaired rivers and streams in the region. Many waterways have incurred stream bank alterations and loss of vegetation creating high levels of sedimentation and changes in depth and velocity of water. Pollutants include chemical elements and compounds such as barium, manganese, nitrogen, phosphorus, silver, copper, sulfates and ammonia. The sources include many of the same lakes listed above, as well as municipal point source, combined sewer overflows, site grading for land development, surface mining and impacts from abandoned mines. Polychlorinated biphenyls, dissolved oxygen levels, sedimentation and siltation, pH values, fecal coli form, total dissolved and suspended solids levels affect both bodies of water as well as rivers and streams in the region and also originate from the sources listed above.