ANALYSIS OF THE DYNAMICS OF THE CONTENT OF BIOGENIC ELEMENTS IN THE SOD-PODZOLIC SOILS OF THE VOLYN POLISSІA

Abstract

We investigated the migration of biogenic elements in the soil profile of the sod-podzolic soil of the Volyn Polissіa. Experimental plots were laid out on arable land near the village Liudyn of the Sarny district of the Rivne region on turf-podzolic clayey drained clay-sandy soil. This soil was formed on alluvial deposits (agro-production group 27b). The results showed that with the depth of the soil profile (0–1.5 m) there is a decrease in humus content from 1.4 to 0.1%, easily hydrolyzed nitrogen decreased from 115.14 to 14.0 mg/kg of soil, phosphorus decreased from 69.0 to 10.0 mg/kg. The potassium content increased in the lower horizons from 10.0 to 28.0 mg/kg. We analyzed the dynamics of the content of biogenic elements from 1981 to 2019. During this period, the humus content fluctuated from min 1.3% (1981–1985) to max 1.9% (2016–2019). This testifies to the low degree of provision of humus. Easily hydrolysable nitrogen increased from 72.0 mg/kg soil (1981–1985) to 84.0 mg/kg soil (2016–2019), although overall, this is a very low level of provision. The content of phosphorus compounds increased from 62.0 mg/kg of soil (1981–1985) to 88.0 mg/kg of soil (2016–2019). This indicates an average level of phosphorus availability. The content of potassium compounds is 69–46 mg/kg, this is a low degree of provision. The obtained results show that the researched agricultural production group 27b of sod-podzolic soil with such indicators has limited opportunities to ensure high yield of agricultural crops. Agrochemically justified application of mineral and organic fertilizers is important for obtaining high yields          and preserving land resources. The choice of undemanding to fertility indicators of agricultural crops is also an important factor.