"Uptake rate standard deviation of nitrate {NO3- CAS 14797-55-8} per hour per unit volume of the water body [particulate >GF/F phase] by isotope-labelled tracer addition, on-deck incubation at simulated in-situ light level, filtration and mass spectrometry on residue"@en . . "SDN:P01::NNUPRSD1" . "The square root of the average of the squares of deviations about the mean of a set of values of the specified measurement."@en . .