BURDUKOVSKII M.L., TIMOFEEVA YA.O.
Agrohimia 2026; (6): 16-26
The post-agrogenic transformation of the content and reserves of total nitrogen and mobile phosphorus in agro-dark-humus podbels (Luvic Albic Mollic Planosols) of Primorsky Krai was studied. Field studies were carried out on fallow areas of various ages (15, 20, 35, 80 and 95 years old) using the chronosequence method. Samples from arable land were used as a control variant. Sampling was carried out along morphological horizons up to a depth of 100 cm. In the first decades after the withdrawal of land from agricultural circulation, the content of mobile phosphorus in the soil decreased significantly. The largest reserves of mobile forms of phosphorus were found in the upper horizon of arable land and in mature fallow. The total nitrogen content in the soil also decreased in the early stages of the fallowing. A steady trend towards the accumulation of total nitrogen in the soil was noted 20 years after the cessation of agricultural use. In a mature 95-year-old fallow, total nitrogen reserves in the 0-25 cm layer exceeded the control level by 22%. The soils of the fallow areas did not differ significantly from each other in terms of the reserves of the studied nutrients.
