STUDY OF SOILS MODIFIED WITH STRUCTURE FORMING AGENTS

摘要

Soil preservation and recultivation are basic guidelines of human scientific and practical activity in environmental protection. Continuous climate changes and improper use of soil lead to its destruction which is an important reason for wind and water erosion and decrease of its fertility. One opportunity for overcoming these unfavorable changes is the use of structure forming agents in soils. Among them, synthetic polyelectrolytes recently attracted the majority of researchers' attention. The present paper reports the results of a study on structure-forming agents synthesized at the "Prof. Dr. A. Zlatarov"- Universuty in Bourgas used with the two main types of soils existing in the mountain of Strandza: "Hromic luvisola" and Vertisols". The mechanical compositions of the spoils were studied by the dry and wet methods of Savinov using fractions with particle sizes of 10, 5, 2, 1 and 0.25 mm. Microscopic observations showed an improved structure of the particles of the soils studied due to the versatility of functional groups present in the structure of the synthetic structure-forming agents used. The physical and chemical properties of the soils studied were also improved. In presence of structure-forming agents, the contents of humus and total nitrogen were found to increase simultaneously with a decrease of pH of acidulous soils. The synthesized structure-forming agents definitely facilitate the decrease of wind and water erosion of soils which is related to minimization of ecological hazards. They are neither toxic nor phytotoxic, which is an important prerequisite for their successful implementation. Last but not least, their positive effect on soil fertility should also be mentioned.