Ecological and agrochemical assessment of soil condition in agrolandscapes within the river basins of the Ivano-Frankivsk region

Abstract

Goal. To carry out ecological and agrochemical assessment of the state of soils in agrolandscapes within the Dniester and Prut river basins of Ivano-Frankivsk region, including residential areas, to identify the impact of anthropogenic load and to propose measures to improve their ecological condition. Methods. Agroecological monitoring was carried out in 2021 – 2024 thanks to the route survey of the territory and laboratory analysis of soil samples using agrochemical methods (humus content, NPK, micro-elements and heavy metals) and physicochemical analysis (pH, hydrolytic acidity, sum of absorbed bases, calcium and magnesium exchange). A mathematical statistical analysis method was used (average value, coefficient of va­riation, minimum, and maximum values of indicators). Results. The study was conducted on sod-podzolic, gray forest, brown mountain-forest, chornozem podzolized, meadow-chornozem, meadow-swamp, and peat-swamp soils, taking into account stabilizing (fallows) and destabilizing (agrolandscapes, including agricultural territory — fields, household plots) ecosystem components. Analysis of soil fertility indicators confirmed their great diversity. Index of metabolic acidity pNsol. varied from very acidic (3.6) to slightly alkaline (7.9), humus content varied from average (2.2%) to very high (8.2%), light hydrolyzed nitrogen — ranged from very low (71.4 mg/kg soil) to high (275.0 mg/kg soil), mineral nitrogen (NNO3+ + NNH4) — from very low (5.0 mg/kg soil) to very high (64.4 mg/kg soil), mobile phosphorus compounds — from low (3.5 mg/kg soil) to very high (1400.0 mg/kg soil), moving potassium compounds — from average (101.0 mg / kg of soil) to very high (1245.0 mg/kg of soil) (according to Machygin). Conclusions. A significant influence of anthropogenic factors on the change of soil fertility indicators in agrolandscapes was determined. In soil samples of brown mountain-forest, sod-podzolic, gray fo­rest, chornozem podzolized, meadow-chornozem, mea­dow-swamp, and peat-swamp soils, selected on household plots, in comparison with fallows and fields, they found more mineral nitrogen — up to 64.4 mg/kg, mobile compounds of phosphorus — 1400.0, potassium — 1245.0, zinc — 20.0, lead — 7.4, cadmium — 0.8, and iron — 248.8 mg/kg. The content of lead and cadmium sometimes exceeded the MPC (maximum permissible concentration). To improve the ecological condition of the studied soils, it is advisable to carry out their systematic monitoring, to introduce elements of soil-protective agricultural technologies, especially in erosion-hazardous areas of brown mountain-forest soils, to regulate the use of fertilizers and pesticides on all types of soils, to carry out liming of acidic podzolized soils, to restore coastal protective strips and anti-erosion plantings on meadow-chornozem, meadow-swamp, and peat-swamp soils, and to develop environmental education of the population and specialists.