THE MICROAGREGATE ANALYSIS OF SOILS BY THE METHOD OF LASER DIFRACTION: THE SPECIFICITIES OF SAMPLE PREPARATION AND RESULT INTERPRETATION

The opportunities of the laser diffraction method in the assessment of the microstructure condition of the soil are shown on the samples of humus layers of the following soils (agro soddy-podzolic (Eutric Albic Retisol (Loamic, Aric, Cutanic, Ochric)), Moscow oblast; gray (Luvic Greyzemic Phaeozem), Tulskie zaseky; migration micellar chernozem (Haplic Chernozem (Loamic, Pachic)), Kursk oblast; ferralitic (Rhodic Ferralsol), Norfolk island). The ways of samples preparation to the analysis are considered: boiling, stirring (80 min-1) of the attenuated water suspensions, intense stirring (2500 min-1) of the water suspensions, mixing of the suspension by the glass stick. The assessment of the preliminary saturation of samples by the distillated water before the samples preparation is given. The assessment of possibility of the implementation of soil micro structure indices, developed on the basis of sedimentation methods was made. The impossibility of the implementation of Kachinskiy dispersion coefficient to the results obtained by the method of laser diffraction was shown. The intense stirring (2500 min-1) of the water suspensions during the 10 minutes is recommended as the standard method of the soil samples preparation for the further microagregate analysis by the method of laser difraction. Such a way of soil samples preparation doesn’t lead to the modification of the properties of the solid body and provides the stability of the results. The results of the microagregate analysis by the method of laser diffraction, presented by the even distribution of particles by the size are characterized by the high informativity. The correlation of different ways of soil samples preparation along with the high accuracy of the method allow us to reveal the specificities of microstructure soil organization.