EPA Grant Number: R83-0633-010
Title: Use of Earthworms to Accelerate the Restoration of Oil and Brine Impacted Sites
Investigators: Kerry L. Sublette, University of Tulsa, Tulsa, OK; Arthur Stewart, Ecological Management Science and Technology, Oak Ridge National Laboratory, Oak Ridge, TN; Greg J. Thoma, University of Arkansas, Department of Chemical Engineering, Fayetteville, AR; Kathleen Duncan, University of Oklahoma, Department of Botany and Microbiology, Norman, OK; Duane C. Wolf, University of Arkansas, Department Crop, Soil, & Environmental Sciences, Fayetteville, AR; Tim Todd, Dept. of Plant Pathology, Kansas State University, Manhattan, KS
Institutions: University of Tulsa, Tulsa, OK; Oak Ridge National Laboratory, Oak Ridge, TN; University of Arkansas, Fayetteville, AR; University of Oklahoma, Norman, OK; Kansas State University, Manhattan, KS
EPA Project Officer: Bala Krishnan
Project Period: January 1, 2004 to December 31, 2005
Project Amount: $447,125
Research Category: Soil Restoration
The restoration of soil ecosystems following remediation of oil and brine spills can be a lengthy process. As the implementation of eco-based standards are implemented, the domestic oil and gas industry (and especially the small independent producers) will need low-cost methods of accelerating the restoration of these sites. The key to this restoration will be the rebuilding of soil structure, which in turn stimulates soil microbial communities and results in revegetation to pre-spill levels of biomass and species diversity. We propose that re-introduction of earthworms to remediated sites can be a cost-effective technology to rebuild soil structure and restore disturbed soil ecosystems.
This project seeks to determine the efficacy of the re-introduction of earthworms to sites which have undergone remediation for crude oil or brine spills in order to accelerate the restoration of these sites in terms of soil quality and plant biomass and species diversity. Specifically we will examine the effects of three treatment variables: earthworms, organic matter, and fertilizer, on the restoration of the two sites referenced above. This will be a two-year project. In the first year measures of soil quality will be the primary indicators of restoration. These measures will include microbial community structure and diversity in terms of phospholipid fatty acid analysis, soil nutrient concentrations, numbers of nitrogen cycling bacteria, nematode numbers and trophic diversity, and earthworm numbers and reproductive status. After earthworms are introduced, no further disturbance of the test plots will be allowed except for sampling. Therefore, some re-vegetation of the plots may occur in the first year. If so, plant biomass and species diversity will be determined at the end of the first growing season. In the second year, plant biomass and species diversity will be added as measures of restoration. All data will be analyzed using analysis of variance (ANOVA). These data are anticipated to lead to a cost-effective protocol for re-introduction and cultivation of earthworms in remediated oil and brine impacted sites and demonstrate the benefits of re-introduction on restoration and re- vegetation of these sites in terms of plant biomass and species diversity. The results of this work can be readily introduced to independent producers, landowners, and the regulatory community in an easily understood manner through IPEC's technology transfer program.