title: The relevance of conditional dispersal for bacterial colony growth and biodegradation.
abstract: Bacterial degradation is an ecosystem service that offers a promising method for the remediation of contaminated soils. To assess the dynamics and efficiency of bacterial degradation, reliable microbial simulation models, along with the relevant processes, are required. We present an approach aimed at improving reliability by studying the relevance and implications of an important concept from theoretical ecology in the context of a bacterial system: conditional dispersal denoting that the dispersal strategy depends on environmental conditions. Different dispersal strategies, which either incorporate or neglect this concept, are implemented in a bacterial model and results are compared to data obtained from laboratory experiments with Pseudomonas putida colonies growing on glucose agar. Our results show that, with respect to the condition of resource uptake, the model's correspondence to experimental data is significantly higher for conditional than for unconditional bacterial dispersal. In particular, these results support the hypothesis that bacteria disperse less when resources are abundant. We also show that the dispersal strategy has a considerable impact on model predictions for bacterial degradation of resources: disregarding conditional bacterial dispersal can lead to overestimations when assessing the performance of this ecosystem service.
authors.affiliation: Department of Ecological Modelling, Helmholtz Centre for Environmental Research - UFZ, Permoserstr. 15, 04318 Leipzig, Germany. thomas.banitz@ufz.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Banitz
authors.forename: Karin
authors.initials: K
authors.lastname: Johst
authors.forename: Lukas Y
authors.initials: LY
authors.lastname: Wick
authors.forename: Ingo
authors.initials: I
authors.lastname: Fetzer
authors.forename: Hauke
authors.initials: H
authors.lastname: Harms
authors.forename: Karin
authors.initials: K
authors.lastname: Frank
mesh_terms: D001419:Bacteria / Q000254:growth & development* / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004777:Environment; D008954:Models, Biological; D016958:Pseudomonas putida / Q000254:growth & development* / Q000378:metabolism*; D012989:Soil Pollutants / Q000378:metabolism
chemical_list: D012989:Soil Pollutants