Applicability of DNA based quantitative microbial source tracking (QMST) evaluated on a large scale in the Danube River and its important tributaries
Reischer, G. H; Kavka, G. G; Kasper, D. C.; Winter, Ch; Mach, R. L; Farnleitner, A. H.
Recently developed methods for the detection of source-specific genetic markers by quantitative real-time PCR (qPCR) offer new opportunities in the field of fecal source tracking. In this study, the large scale applicability of the recently developed human-specifi. QMST BacH method was tested on samples taken along the whole Danube River and its important tributaries with a catchment area of approx. 800,000 km² and 81 million inhabitants. Human feces-specific BacH marker sequences could be detected all over the investigated area. A high correlation between the marker concentrations and classical microbiological parameters was apparent. Regression analysis with fecal coliform (FC) data showed that 62% (complete data set), 70% (tributaries) and 40% (Danube River samples) of the variations in FC were explainable by the respective variations in QMST BacH data. The results demonstrate the applicability of modern DNA-based QMST methods on the investigated large scale and recommend their use in future strategies for quantitative faecal source tracking.