2.1.2. Soil Organic Carbon

The total carbon content of the samples was determined using a TruSpec CHN analyser by Leco (St. Joseph, Michigan, USA). Additionally, a small portion of the powdered material from all samples was tested for its carbonate content using 9.9% HCl acid. None of the samples showed signs of carbonate, which is why the measured total carbon content is interpreted as the total organic carbon content. During measurement, the samples were dry combusted at 950 ◦C in an oxygen atmosphere, and carbon fluxes were quantified by infrared spectroscopy. The results were calibrated using certified

reference material (CRM; Leco 502–309; 12.29 ± 0.37 mass% C; Leco 502–308; 3.6 ± 0.29 mass% C; reproducibility was <2% RSD) and are reported as soil organic carbon (SOC) in mass%.
