The Resazurin (Raz) – Resorufin (Rru) tracer system is widely used in hydrological studies. In most field experiments a lack of mass balance closure is reported and, to date, it is still unclear what drives incomplete recovery. We designed controlled laboratory experiments varying the initial concentrations of Raz, the test durations, and the type of microorganisms present to quantify mass balances of Raz and Rru in the absence of other suspected causes of incomplete recovery in field experiments (e.g., sorption to sediments and photodecay) in order to test if microbial activity alone could explain incomplete recovery. We used the summation of Raz and Rru concentrations over time to assess mass recovery and variability. The uploaded datasets present Raz and Rru concentrations measured during our experiments.
Results are published in Dallan et al. (2020) - doi: 10.1029/2019JG005435

Files organization:
“EXP_DESCRIPTION.docx” describes experimental set up, sampling and measurement methods.
“DATASET.xlsx” contains data concentrations of Raz and Rru obtained for the 4 experiments. Each sheet refers to one experiment. Table A summarizes experiment set up. Table B shows Raz concentration for the 18 flasks at the different sampling times. Table C shows Rru concentration for the 18 flasks at the different sampling times. Times are expressed in hours [hh], measured from the time of initial Raz addition to the flasks. Concentrations are expressed in micromol per liter [umol/L]
“RECOVERY_DATA.xlsx” contains data calculated from measured concentrations ("DATASET.xlsx"). Each sheet refers to one experiment. Tables S2-S5 summarizes main results about total recovery (Raz + Rru): for each series (50, 100, 200, 300, 400 ppb) and each sampling time k, we reported:
- the average concentration for the 3 replicates of each series [umol/L];
- the standard deviation of the concentrations associated at the 3 replicates [umol/L];
- the recovery percentage at each sampling time k.
In the last two rows, for each i series, we reported:
- the averaged total concentration [umol/L];
- the variability (standard deviation) associated with the recovery percentages.