Nitrogen and Carbon Reserves in Soils of the Terek-Kuma Lowland

Abstract

The purpose is to determine of nitrogen, carbon concentrations and reserves in light chestnut, meadow-chestnut soil types and typical saline under various plant associations of pasture phytocenoses in the protected conditions of the Terek-Kuma lowland. Materials and methods. Using the photometric method "in-dianalove green" for determining total nitrogen, the method of Tyurin and Kononova for easily hydrolyzable nitrogen, by Tyurin method for humus and calculation of carbon for the study of nitrogen and carbon pool in soils. Results and discussion. Total nitrogen ranges from 0,15-0,20%, and easily hydrolyzable nitrogen ranges from 2,4-5,3 mg/100 g in the studied soil types, which is on average 2,5 times higher than in virgin soils (control). The humus horizon of meadow-chestnut soil (5,2 t/ha) under wormwood-cereal and light- chestnut (5,0 t/ha) under ephemeroid-wormwood-cereal compared to typical saline (4,3 t/ha) under mixed grass-firepetrosimonium associations. Nitrogen and carbon reserves in the soil in autumn compared to spring are 1,5 times lower, and 1,6-1,8 times lower compared to the control, which is associated with an increase in the productivity of the phytocenosis in the protected regime. Conclusions. Studies of the modern state of nitrogen and carbon soil of the foundation of the Terek-Kuma lowland in protected regime showed that intensive grazing load, reducing the number of species and percent cover of phytocenosis, leads to the transformation of the soil, its physical and chemical properties (decrease in humus content, adsorption capacity, total and hydrolyzable nitrogen and other elements).