Research About Abnormal Reaction Of Springs Bacteria To Pre-earthquake In North Tianshan Region

Objective: To explore a kind of new technology of earthquake monitoring based on bacteria community.Consequently, typical monitoring spring spot from northern Tianshan area for earthquake was No.10Spring in Urumqi that were used to study their reflecting earthquake law of bacteria community andmetabolic characteristics of sensitive bacteria for felt earthquake using three different methods, andanalysis of the effect of these methods, water samples were collected from monitoring period which feltearthquakes occurred and the epicenter was100kilometers away from the No.10Spring in Urumqi.Methods: On the one hand, we used plate culture counting methods and BIOLOG GEN III bacteria plate tomonitored bacterial activity and functional diversity changes during the pre-and post-earthquake stagesfrom cellular level. On the other hand, we used terminal restriction fragment length polymorphism(T-RFLP) technology to analysed bacterial community composition changes during the pre-andpost-earthquake stages from molecular level. And study the correlation between bacterial communities andenvironment factors by canonical correlation analysis (CCA). Results: The result showed that springbacterial numbers presented stochastic dynamic changes through the year. The culturable bacteria numbersand average well color development (AWCD) of carbon source utilization of bacterial community weresignificantly higher after the earthquake. Besides, there were some correlations with magnitude andepicenter distance of earthquake. The main carbon source utilization types of sensitive bacteria group forfelt earthquake were sugar alcohol at the No.10Spring. We screened6typical carbon sources of71carbonsources from the GEN III plate which could reflect the differences of the pre-and post-earthquake springbacterial community structure and made the validation test set to the pre-and post-earthquake samplesusing the discriminant function. The discriminate rate of the overall accuracy was96.2%, these six kindsof carbon source respectively, Glycerol, Glycyl-L-Proline, Quinic Acid, L-Lactic Acid, Propionic Acid andAcetic Acid. Most bacterial community diversity indexes of pre-earthquake were higher thanpost-earthquake on the composition of spring bacteria community. Besides, there were some correlationswith magnitude, hydrogeochemical and the volumes of filling spring water. To begin with, during the pre-and post-earthquake stages, the greater the earthquake magnitude was, the more the spring bacteria newgroups discovered, and under the similar magnitude for earthquake, the deeper the depth of seismic focuswas, the fewer the spring bacteria new groups discovered. Next, abundance of spring bacteria new groupswere higher before the earthquake. Finally, some bacterial advantage groups were disappeared. Theabundance of spring bacteria new groups with hydrogeochamical parameters were analyzed by CCA(Canonical correspondence analysis). The results showed that spring bacteria new groups were significantlypositive correlate to radon (Rn) change, and were significantly negative correlate to sulfide change.Conclusion: Culturable bacteria numbers and carbon source utilization of bacterial communities showedsome reflecting earthquake law. The seismic precursor was monitored in northern Tianshan area by usingBIOLOG technology that the statistical prediction accuracy rate increased to56.8%. Spring bacteria newgroups were founded during the pre-and post-earthquake stages by using T-RFLP technique.