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The purpose. To assess nature of soil after long-term agrarian use on the basis of agrophysical parameters. Methods. General scientific: comparative, analytical, laboratory: structural-aggregate composition of soil was determined by method of dry screening according to Savvinov; water-resistance of aggregates — according to Baksheyev; microaggregation analysis. Researches were carried out in long field stationary experience of O. Dushechkin’s faculty of agrochemistry and quality of produce of plant growing which was started in 1961 in «Agronomic exploratory station» of NUBNM of Ukraine. Results. Changes in structural-aggregation and microaggregation content of meadow-chernozem soil were studied at its use during 60 years in 10-field crop rotation in comparison with virgin land. The highest content of aggregates (more than 1 mm) was registered for virgin land: 70,6 – 78,1% in 0 – 40 cm layer; a little lower - in alternative with fertilization of clover (61,8 – 80,5%), and the lowest — at growing sugar beet at one-and-a-half norm of fertilizer (60,0 – 74,1%). Structure factor varied analogously. Aggregation factor for clover field at one-and-a-half norm of fertilizer essentially improved and made 0,914 – 0,974 in 0 – 40 cm layer of soil. Average diameter of corpuscles augmented downwards the profile of meadow-chernozem soil. Conclusions. It was determined that importation of one-and-a-half dose of complete fertilizer resulted in aggravation of water-resistance of aggregates: content of water-resistant aggregates in alternative with fertilization under sugar beet made 75 – 85,9%, in alternative without fertilizers — 80,3 – 84,5%. At presence of clover field in 10-field crop rotation there was no radical aggravation of meadow-CHERNOZEM SOIL in comparison with virgin land. Gradual aggravation of its structure was observed. But use of clover field in alternative with 1,5 dose of fertilizer under crops of 10-field crop rotation improved soil structure. |
