Agrochemical state of arable soils in Central Black Soil Region of Russia
The article presents results of full agrochemical survey of arable lands of Central Black Soil Region of Russia and statistical information on dynamics of fertilizer application and liming of acid soils. The results of full agrochemical survey of arable lands, carried out by agrochemical service, were used in the work. In soil samples it was determined: the content of organic matter using Tyurin method in modification of Central Research Institute of Agrochemical Service for Agriculture (GOST 26213-93), pH of salt extract (GOST 26483-85), content of mobile forms of phosphorus and potassium according to method, described by Chirikov (GOST 26204-91), mobile forms of copper - according to GOST R 50683-94, manganese - according to GOST R 50685-94, zinc - according to GOST R 50686-94. To extract mobile forms of elements from soil acetate-ammonium buffer solution with pH 4.8 was used. The current soil fertility is analyzed according to the main indices. The highest weighted average content of organic matter (6.6%) and mobile forms of zinc (1.7 mg/kg) are characteristic for soils of Tambov region; of mobile forms of phosphorus (137 mg/kg), potassium (145 mg/kg) and manganese-for soils of Belgorod region. The highest content of mobile copper (0.29 mg/kg) is characteristic for soils of Kurgan region. The lowest weighted average content of organic matter (4.63%), mobile forms of potassium (96 mg/kg) and manganese (6.8 mg/kg) was registered in soils of Kursk region, of mobile forms of phosphorus (90 mg/kg)-in soils of Tambov region, of copper (0.11 mg/kg)-in soils of Belgorod region, of zinc (0.39 mg/kg) - in soils of Voronezh region. The lowest part of acid soils (27.98%) was in Voronezh region, the highest one (75.41%)-in Tambov region.