Nitriver 3 tnt reagent set

Temperature, pH, conductivity,
and dissolved oxygen were measured using the Orion Star A325 pH/Conductivity
Portable Multiparameter Meter (Thermo Scientific, catalog no. STARA3250).
Total chlorine was measured using HACH Method 8167 (HACH, catalog
no. 2105669). Ammonium, nitrate, and nitrite were measured using the
Nitrogen-Ammonia Reagent Set (method 10023, HACH, catalog no. 2604545),
NitraVer X Nitrogen-Nitrate Reagent Set (method 10020, HACH, catalog
no. 2605345), and NitriVer 3 TNT Reagent Set (method 10019, catalog
no. 2608345), respectively. All HACH measurements were performed on
the DR1900 Portable Spectrophotometer (HACH, catalog no. DR190001H).
For metal analysis, samples were acidified with 2% nitric acid and
digested for a minimum of 16 h before being analyzed via inductively
coupled plasma mass spectrometry (ICP-MS) according to method 3125
B.²⁸ Blanks and spikes of known concentrations
were measured every 10 samples for quality control. Samples for dissolved
organic carbon (DOC) and total dissolved nitrogen (TDN) were acidified
to pH <2 using HCl before being analyzed using a Shimadzu TOC-V_CPH total organic carbon analyzer with a total nitrogen module
attached.^{29 (link)} Certified DOC and TDN quality
references from ULTRA Scientific (Agilent, catalog nos. QCI-731 and
QCI-745) were measured to confirm precision and accuracy.

Water quality parameters (i.e., temperature, pH, conductivity, and dissolved oxygen) were measured using the Orion Star A325 pH/conductivity portable multiparameter meter (Thermo Scientific; catalog no. STARA3250). Total chlorine was measured using U.S. Environmental Protection Agency (U.S. EPA)-approved Hach method 8167 with DPD total chlorine reagent powder pillows (Hach; catalog no. 2105669). Reactive orthophosphate was measured using U.S. EPA-approved Hach method 8048 with PhosVer 3 phosphate reagent powder pillows (Hach; catalog no. 2106028). Nitrogen species, including ammonium, nitrate, and nitrite were measured using the nitrogen-ammonia reagent set (method 10023; Hach; catalog no. 2604545), NitraVer X nitrogen-nitrate reagent set (method 10020; Hach; catalog no. 2605345), and NitriVer 3 TNT reagent set (method 10019; catalog no. 2608345), respectively. All Hach measurements were performed in triplicate on the DR1900 portable spectrophotometer (Hach; catalog no. DR190001H) (Table S1).

Water quality parameters (i.e., temperature, pH, conductivity, and dissolved oxygen) were measured using the Orion Star A325 pH/conductivity portable multiparameter meter (Thermo Scientific; catalog no. STARA3250). Total chlorine was measured using U.S. Environmental Protection Agency (U.S. EPA)-approved Hach method 8167 with DPD total chlorine reagent powder pillows (Hach; catalog no. 2105669). Reactive orthophosphate was measured using U.S. EPA-approved Hach method 8048 with PhosVer 3 phosphate reagent powder pillows (Hach; catalog no. 2106028). Nitrogen species, including ammonium, nitrate, and nitrite were measured using the nitrogen-ammonia reagent set (method 10023; Hach; catalog no. 2604545), NitraVer X nitrogen-nitrate reagent set (method 10020; Hach; catalog no. 2605345), and NitriVer 3 TNT reagent set (method 10019; catalog no. 2608345), respectively. All Hach measurements were performed in triplicate on the DR1900 portable spectrophotometer (Hach; catalog no. DR190001H) (Table S1).