Pretreatment Of Soil Samples Research Articles

Hamburg University Radiocarbon Dates III

The following list consists of dates of soil samples, partly produced in the former Bonn laboratory and bearing the code designations, BONN, and partly in the present dating lab at Hamburg University. The list comprises Mollisols and Inceptisols from Germany, sampled by layer and dated as whole soil, hydrolysis residue, and hydrolysate. Other profiles represent selected Australian Vertisols and Krasnozems, sampled by layer as well. Dates derived from marshes of the Elbe River as well as from paleosols buried by coastal levees are also included in the list. Pretreatment of soil samples is described in Scharpenseel and Pietig (1969) and Scharpenseel (1972; 1977).

Pretreatment of soil samples before NO3-N analysis.

Storage of sandy, loam and clay soil samples at 35 deg C or 70 deg C for 2-3 days reduced the NO3-N level in the soils. Freezing (-20 deg C), refrigeration (-4 deg C) or storage at room temperature for 2-3 days had little effect on NO3-N levels, although low or room temperature storage for 2 months increased NO3-N levels in the loam and clay soils. Freezing or refrigeration of the sandy soil for 2 months reduced NO3-N levels, while long storage at room temperature markedly increased NO3-N levels in this highly organic soil. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Soil radiocarbon analysis and soil dating

Based on14C dating principles, techniques of measuring14C concentrations in pedogenic organic materials have been well established. Basic lines of soil sample pretreatment for radiocarbon analysis by liquid scintillation are shown. Possible influences of lithogenic carbon on the results obtained are discussed.

Rapid determination of nitrate nitrogen in soils

A simple but effective method for pretreatment of soil samples is suggested. The application of an electrodynamic vibrator or ultrasonic device eliminates the necessity for continuous stirring in direct potentiometric determination of nitrate nitrogen. It also makes the extraction process faster, and the apparatus could easily be used in automatic systems for continuous soil control.

On the pre-treatment of samples of heavy clay soil for determinations by the pressure membrane apparatus

The method of pre-treatment of soil samples should be chosen in each case according to the purpose of study, keeping in mind the slow reversibility of the wetting undergone by heavy glacial clay. In general, it is recommended that the air-dry samples ground to 2 mm should be soaked for three weeks prior to determinations by the pressure membrane apparatus. If it is desired to make direct determinations, grinding to pass 0.6 mm appears to be conducive to good wetting, in the case of topsoils.