blaCTX-M antibiotic resistance genes, fecal indicator organisms, general water characteristics and nutrient concentrations Lahn River

Concentrations of blaCTX-M antibiotic resistance genes, fecal indicator organisms Escherichia coli, intestinal enterococci and somatic coliphages as well as general water characteristics and nutrient concentrations were quantified weekly over a 12-month period in Lahn River surface water grab samples at two sampling sites (Nievern and Obernhof). Concentrations of blaCTX-M antibiotic resistance genes were quantified using quantitative real-time PCR according to Marti et al. (2013). Data of fecal indicator organisms (i.e. Escherichia coli, intestinal enterococci and somatic coliphages), general water characteristics and nutrient concentrations were obtained from Herrig et al. (2015). Escherichia coli, intestinal enterococci and somatic coliphages were quantified according to standard methods ISO 9308-3, ISO 7899-2, and ISO 10705-2. General water characteristics including water temperature, specific conductivity, pH, turbidity, dissolved oxygen and chlorophyll-a were measured in situ with a YSI 6600 V2 multiparameter sensor (YSI, USA). Quantification of nutrient concentrations relied on spectrophotometric measurements (Xion 500, Hach-Lange, Germany) by ready-to-use cuvette tests (Hach-Lange, Germany).