BIOCOMPLEXITY - INCUBATION ACTIVITY: Quantitative description of the response of a complex system to disturbance: subsurface microbial communities and chemical contaminants

University Of Virginia Main Campus, Charlottesville VA

Investigators

Abstract

Ford 0083839 The release of chemical pollutants into groundwater disturbs the resident microbial community and triggers a complex network of feedback loops affecting the groundwater geochemistry, soil structure and microbial diversity of the system. Human intervention in the form of engineered remediation to restore the site introduces yet another disturbance to which the microbial community and abiotic components of the systems must respond. An emergent property typically associated with microbial communities is homeostasis. The objective of this research is to test the homeostasis hypothesis for a subsurface microbial community under the stress of a chemical pollutant release and the remedial actions which may follow. To accomplish this objective will require effective collaboration among a team of scientists and engineers with expertise in microbiology, hydrology, biogeochemistry, engineering, ecological modeling, adaptive control theory, and data visualization. Incubator activities are designed to foster communications between experimentalists with an understanding of the physical system and mathematical modelers with quantitative tools for characterizing and predicting properties of the system. A relatively simple laboratory experiment [two bacterial species within a fixed-film flow-through column with a reactive mineral surface (iron) that serves as an alternative election acceptor in the absence of oxygen] is defined in order to explore three modeling approaches: (1) system of nonlinear partial differential equations for each species, (2) metabolic modeling, and (3) adaptive control theory. This prototype system will be used to focus the interdisciplinary discussions on a concrete problem and facilitate productive interactions. Additional modeling approaches will be explored through a brainstorming session, computer systems and a follow-up videoconference. A written summary from the workshop will be published in technical news journals to benefit the scientific community at large.