Purtova L.N.
Bulletin of higher educational institutions. North Caucasus region. Natural sciences 2021; (3): 111-116
The differences in the qualitative composition of organic matter in the soils of natural and anthropogenically transformed landscapes in the south of Primorye were established by the method of chemodestructive fractionation (CDF). The lowest indices of the easily oxidizable part (EOP) in the organic matter are typical for soils of technogenic landscapes (embryozems) with very low humus content due to low reserves of aboveground phytomass and the supply of fresh organic matter of plant origin. Embryozems are characterized by a low supply of humus with nitrogen. Higher EOP values are characteristic of soils of natural landscapes (burozems) with average humus content. In burozems, oxidative and eluvial processes are balanced by humus formation. In the soils of agrogenic landscapes (agro-dark-humus podbeles, agro-dark-humus gley soils) with low humus content, the proportion of EOP decreased and, at the same time, the proportion of the hardly oxidized part in the composition of soil organic matter increased. Some increase in EOP was recorded in agro-dark-humus gley soils with rump crops, which is associated with the intensification of the transformation processes of organic matter and the transition of organic matter from the difficult-to-oxidize to the easily oxidized part. Based on the data obtained on the qualitative composition of organic matter, the CDF method implies that in the soils of natural landscapes (burozems), the proportion of EOP exceeded that in comparison with soils of agrogenic (agro-dark-humus podbely, agro-dark-humus gley) and technogenic landscapes (embriozems). This indicates differences in the conditions of soil formation and the ongoing oxidative and humus-forming processes.
