Comparison of in situ trace element concentration of soil water with concentration in aqueous extracts as a background concentration level

摘要

This study compares concentrations of trace elements measured in soil water samples with concentrations determined in batch experiments as a background concentration level. One batch experiment was conducted at a liquid/solid (LS) ratio of 5 L/kg withsamples specifically adjusted for ionic strength using Ca(NO_3)_2 as the background electrolyte. The other is an aqueous extract at a LS ratio of 2 L/kg. Both batch experiments show similar results in their ability to estimate in situ concentrations. The results illustrate that for most trace elements the concentrations, which are determined in extracts, show statistically significant relations (p-value <0.01) with those measured in in situ soil percolation water. The level of fit measured by R~2 increases in the following order Pb, Cr