PHOSPHORUS AND POTASSIUM RESERVES IN THE MAIN TYPES OF ZONAL SOILS OF THE CHELYABINSK REGION

Abstract

One of the most important tasks of land monitoring is to control the content of gross and mobile forms of basic nutrients in soils. The phosphate-potassium regime of the soil depends not only on its type and the geochemical composition of the soil-forming rock, but also on the landscape and the level of chemicalization of the soil. The low content of phosphorus in the soil in the main area of agricultural land limits the productivity of agrocenoses. The reserves of potassium in the soils of the region are quite high. However, monitoring of this indicator is still important. A comparative assessment of the phosphate-potassium regime of arable land and virgin lands under the same soilforming process is of scientific and practical interest. According to the research results, it has been established that black soils have the highest reserves level of gross and mobile forms of phosphorus. Dark gray mountain-forest soils have the lowest one. A widespread decrease in the reserves of mobile phosphorus in agricultural soils was revealed. This tendency is especially pronounced in dark gray mountain forest soils, ordinary and southern black soils. According to the results of monitoring, it was revealed that the reserves of exchangeable potassium in the main area of arable land and virgin land are gradually increased. In the dark gray mountain-forest soils, as well as leached black soils for five rounds of the survey, the reserves of exchangeable potassium decreased. It is necessary to adjust the dose of fertilizers into the farms with updated information on the agrochemical properties of the soil, taking into account the content of phosphorus and potassium in the arable layer. Also it is of great importance to take into account their removal with the crop and the utilization rate of nutrients from the soil and fertilizers.