Agroecological Assessment of Sod-Podzolic Gleyic Soil Agrocenosis and Fallow Land in the Yaroslavl’ Region

Purpose: to identify trends in fertility indicators changes in post-agrogenic soils during plowing and further agricultural use. Materials and methods. The study was conducted in 2023 in a landscape with sod-podzolic gleyic soils located in the Yaroslavl region. Research methodology is the following: field experiments and laboratory studies using generally accepted soil status analysis methods. Results. The humus content of the sod-podzolic gleyic fallow soil increased by 1.46 % over a 28-year period. In the agrocenosis, the amount of water-soluble humus increased by 2.26 mg CO₂/100 g of soil. No significant differences in the humus group composition between the fallow and arable soils were found. The average content of Р₂О₅ in the 0–20 cm soil layer of the biocenosis was 261.7, and in the agrocenosis – 170.8 mg/kg; К₂О in the 0–20 cm soil layer of the biocenosis was 134.3, and in the agrocenosis – 93.5 mg/kg. There was an increase in hydrolytic acidity from 0.93 to 1.25 mg-eq/100 g of soil, and pHsalt from 6.09 to 5.55 units. The degree of soil saturation with bases noticeably decreased – from 93.6 % in the biocenosis to 91.9 % in the agrocenosis. In the agrocenosis, there was a decrease in the abundance of nematodes (–47,2 %). compared to the biocenosis. When growing agricultural crops, catalase enzyme synthesis in the soil was 31.8 % more intense than under natural vegetation. Soil “respiration” under an agrocenosis is 30.2 % higher than under a biocenosis. Conclusions. A comparative assessment of the agrocenosis and secondary biocenosis based on key ecological and agrochemical indicators revealed that anthropogenic intervention during crop cultivation in a landscape with sod-podzolic gleyic soil significantly reduces the humus content and availability of mobile phosphorus and potassium, deteriorates its physicochemical state, and intensifies biochemical processes. The secondary biocenosis is in a relatively stable natural state.