Properties of hymatomelanic acid peat and its influence on the growth processes of spring wheat varieties Iren

In this paper, we consider two ways for obtaining hymatomelanic acid extraction into conventional Soxhlet extractions: directly from the peat and from the dry product of humic acid. The results of the study of the elemental composition of humic and hymatomelanic acids are presented, their similarities and differences are analyzed. In order to study the effect of humic and hymatomelanic acid preparations on the growth processes of spring wheat, a vegetation experiment was conducted. Peculiarities of biological action of the solutions and hymatomelanic and humic acids of different concentrations in spring wheat varieties “IREN” were investigated. The paper presents a method for determining the ash content of the studied peat, as well as, calculations of the economic feasibility of using preparations based on the hymatomelanic acids.

THE DECOMPOSITION OF RADIOACTIVE ACETATE IN SOILS: II. THE DISTRIBUTION OF RADIOACTIVITY IN SOIL ORGANIC FRACTIONS

Soils incubated with C14-labelled acetate for 6 to 9 hours showed that 22–30% of the acetate was oxidized to CO2. Fractionation of the soil revealed that the radioactivity of the remaining substrate was widely distributed in various fractions. Greatest activity was noted in the acid hydrolyzable humin fraction (50%) with lesser amounts (5–10%) being recovered in the fulvic acid and alcohol extract. Hymatomelanic acid, α-humus, and β-humus contained only traces of activity.Ion-exchange separation of the acid hydrolysate of the humin fraction indicated that a considerable portion of the activity was associated with an unidentified compound which had certain characteristics of itaconic acid. Radioactivity was also found to be present in the 15 amino acids identified.

The preparation and fractionation of humic acid

The early authorities, Mulder, de Saussure, Berzelius and others, considered the whole of the precipitate obtained by adding acid to an alkaline extract of soil to be humic acid,—a single substance to which they assigned a definite formula. Hoppe-Seyler and others found, however, that the precipitate was not homogeneous; a portion dissolved in alcohol, which he named hymatomelanic acid. It was from this that Schreiner and Shorey isolated a number of organic acids, all of which were either colourless or only faintly coloured.