. . . . . . . . . . . . . . . . . . . "The square root of the average of the squares of deviations about the mean of a set of values of the specified measurement."@en . "SDNO3+NO2_SedPW" . . . "accepted"@en . . . . "SDN:P01::SDNZPWD1" . . "Concentration standard deviation of nitrate+nitrite {NO3+NO2} per unit volume of the sediment pore water [dissolved plus reactive particulate . . .