Prairie Restoration Impacts on Soil Microbial Communities at the Illinois Nachusa Grassland Research Site The National Research Council has determined that there needs to be more research in the "critical zone," or pedosphere, which is the near surface environment where interactions take place between rock, soil, air, water, and biota (National Research Council, 2000). In particular, detailed information is needed about the kinds of microorganisms present throughout the whole pedosphere and how they vary in time/space and with land usage. The proposed microbial observatory is dedicated to research on bacteria in the pedosphere during prairie restoration in Illinois and is expected to build associations between the fields of classical microbiology, molecular microbiology, soil science, geology, and geography. There is a paucity of such studies examining soil microbial communities in the whole pedosphere. Typically, bacterial community studies examine the rhizosphere (0-20 cm), which is only the upper part of the whole pedosphere. Soil microorganisms remain some of the most difficult communities to characterize because of their immense phenotypic and genotypic diversity. In addition, predicting how microbial community structure responds to environmental perturbation, such as land usage changes or application of agrochemicals, has been difficult to determine. Research will be conducted at the Nachusa Grassland research site in northern Illinois that is owned and managed by The Nature Conservancy. The site affords a rare opportunity to compare microbial-pedologic linkages in native tallgrass prairie, restored tallgrass prairie, and presently cultivated agricultural crops. Approximately 0.03% of the pre-settlement tallgrass prairie remains in the intensively cultivated Midwestern United States, therefore research integrating physical and chemical soil properties with microbial communities needs to be conducted in this nearly extinct ecosystem. The principal hypothesis of this study is that land usage changes such as prairie restoration will systematically change the bacteria community along a given hillslope not just in the rhizosphere but also throughout the whole pedosphere. The second hypothesis is that bacteria located in the always cultivated and restored areas will have a capacity to biodegrade organic agrochemicals, while soils in the never cultivated areas will not. The objectives of this research are to: 1. Determine the changes to physical and chemical factors in the whole pedosphere that occur during prairie restoration and link these changes to the microbial community. 2. Assess the bacterial community structure throughout the whole pedosphere both spatially and temporally. This objective will undertake a comprehensive inventory of bacteria in the whole pedosphere, by combining enrichment, phospholipid fatty acid analysis, and molecular techniques (cloning/sequencing, RNA analysis, real-time PCR, and fluorescence in situ hybridization) to examine microbial communities in soils. 3. Determine if microorganisms present in samples of the native tallgrass prairie, restored tallgrass prairie, and presently cultivated agricultural crops have the potential and activity to biodegrade organic agrochemicals and identify microorganisms responsible for biodegradation. 4. Provide research and research training to undergraduate and graduate students by providing research projects and classroom instruction in the areas of classical microbiology, molecular microbial ecology, soil science, geology, and geography.