Азот в почвах склоновых экосистем cреднегорья Дагестана

Abstract

This work is determined by the primary importance of determining the content and reserves of nitrogen in typical soils of the Middle-Mountain subprovince of Dagestan, since the potential nitrogen reserves are estimated by the total nitrogen reserves, and the practical soil fertility of the territory is estimated by the easily hydrolyzed nitrogen used by plants. The aim of the study - determination concentration of easily hydrolyzable and total nitrogen, their reserves in typical soils of the Mid-Mountain subprovince of Dagestan, with their reserved content, was determined. Scientific novelty. For the first time in the conditions of the Middle Mountains of Dagestan, the reserves of soil nitrogen were determined. Total nitrogen was determined by the photometric method of "indophenol greens" according to the CIAS method, easily hydrolyzable nitrogen according to Tyurin and Kononova. The results of the study showed that the mountain brown forest soil was more fertile on the slope of the northern exposure of Mount Mayak, since it revealed more humus by 14.88 % and easily hydrolyzable nitrogen by 14.38 % than in the 0-20 cm layer of mountain meadow-steppe soil. The accumulation of total nitrogen in the upper 0-20 cm layer was 0.247 % for mountain brown forest soil, and 8.81 % less for mountain meadow-steppe soil. Nitrogen reserves in soils also differed - less reserves in the 0-20 cm layer were 6.7 % and 12.16 % were in the mountain meadow-steppe, respectively, of the general and easily hydrolyzed form. This is probably due to the steeper slope of the southern exposure, to which the mountain meadow-steppe soil is confined. A large number of nitrogen reserves in mountain brown forest soil may be associated with its location at the foot of the forest.