Evaluation of structural aggregation processes of typical chernozem under conditions of algal biofertilizers application

Abstract

The management of the aggregation-structuring processes implies the intensification of the soil pedoplasm modeling processes under the direct and indirect action of the its biota. In the present research we started from the consideration of algal microflora as the nucleus of bacterial-algal cenosis responsible for the decomposition of various groups of organic substances (geno-metabolic networks). They decompose organic waste in consecutive series ensuring a closed circuit of substances and energy with development of the aggregate level of structural-functional organization of the soil organo-mineral biopedoplasm. It has been established that algalization of the typical moderately humiferous strongly overplowed chernozem through administration of algal biopreparations leads to the regeneration of the humification process and the improvement of the structural-aggregate condition of the soil. The mechanisms of this process are determined by the participation of algal biomass as a source of biological nitrogen for the humification process. Under algalization conditions, the aggregation processes proceed with the formation, mainly, of 5-1 and 3-0.5 mm aggregates and are determined by the agglutination processes with the participation of newly formed humic substances. The intensity of the aggregation-structuring processes differs depending on the species of administered cyanophyte algae and can be described with the following sequence in the sense of decreasing it: Nostoc gelatinosum > Combined lot > Cilindrospermum licheniforme > Calothrix gracilis > Nostoc linckia. The cyanophyte algae participate less in the direct aggregation processes of soil biopedoplasm. At the same time, the practiced technologies require crop rotations capable of contributing to increasing the degree of aggregate stability. In the pedofunctional aspect, the process of algalization of chernozems presupposes perspectives for sustaining the composition and diversity of the soil microbiome.