Wednesday, November 15, 2006

Alterations to Soil Microbial Activity Following 80 Years of Agriculture at Emiquon.

Leah Barth, Biology Dept, Bradley Univ, 1501 W Bradley Ave, Peoria, IL 61625

Emiquon is the site of one of the largest floodplain restoration efforts in the U.S. In the 1920’s lakes and wetland areas along the Illinois River were converted into agricultural fields. To investigate the impacts of conversion from agriculture to wetland ecosystems on soil characteristics, research focused on differences between the characteristics of agricultural fields and the remnant wetlands. Differences in pH, bulk density, field capacity, texture and nitrogen mineralization were found among the sites. There are pH ranges that are ideal for soil microbe and plant survival and reproduction. Differences in pH among the sites could create differences in the types of microbes and plants that are able to establish and survive.  Bulk density, field capacity, and soil texture affect pore space and soil moisture, which has an affect on the success of microbe and plant life. Nitrogen mineralization rates were much high for the wetland sites. Since nitrogen is important for plant life, differences in the amount of available nitrogen could have a significant affect on the type of plants that establish at the restoration sites. Overall, there appears to be minimal differences in soil characteristics between the agricultural fields sampled, but there are significant differences between these sites and the remnant wetland. The differences could have a major impact on site restoration.