2.2. Physicochemical analyses
Ammonium, nitrate, nitrite, and phosphate transport were measured by flow (injection) colorimetric analysis using a computer-controlled FOSS FIAStar 5000 apparatus. The NH4+, NO2-, NO3-, and PO43- concentrations were determined using a spectrophotometer and recalculated as N-NH4+, N-NO2-, N-NO3-, and P-PO43-. Samples from the mountain streams were collected monthly using the bathymetric method (containers with a volume of 1 dm3). The concentration of the TSS was determined by the gravimetric method (after drying) using tarred filters (with an accuracy of ± 0.0005 g). The dry residue (sum of mineral particles from the transported samples) from the collected material was filtered to determine the concentration. The total number of water samples was 140, collected over five years from April to November each year.