Laser diffraction spectra’s deconvolution in the study of soil texture

Abstract

The deconvolution procedure for separating the original particle size distribution spectrum by laser diffraction (LD) gives a different share of the fractions compared to the common method, when the number of particles is determined in the vertical walls at the group boundaries according to the FAO classification or other classification. In addition, a new indicator provides information on the prop- erties of individual fractions by particle size: the LD fractions dispersion (D). Vertisols have a harder texture after deconvolution, especially in the Stavropol Vertisols, and the less extent in the Texas Vertisols. Vertisols have relatively low dispersion D < 0.7, which means relatively homogeneity of LD-fractions. Andosols dispersion (D) is very high; as a result of small number LD fractions, less than the number of FAO fractions. Very high D values can be attributed to preservation aggre-gates due to incomplete dispergation of soil. A strong disturbance in the distribution of LD-fractions and a high degree of their superposition makes it possible to assume that micro aggregates will remain in them after not adequate chemical preparation for LD analysis.