Dynamics and perspective of calcium supply of arable soils and grasland in Belarus

Abstract

The results of Agrochemical Soil Survey for 1989–2020 showed an acceptable level of exchangeable Ca-supply of arable soils and grassland in Belarus due to long term systemic liming of acidic soils. At present, 81,9 % of the area of arable and 93.1 % of improved grassland are characterized by an optimal and high content of Ca2+. Due to a significant decrease in the required volumes of liming in recent years, there is a noticeable acidification of arable soils in most regions of the republic. This can lead to a loss of exchangeable calcium and degradation of soil fertility.
Two scenarios are discussed for forecasting the availability of arable soils with exchangeable calcium for the period up to 2035 in the regions of Belarus: 1 – optimistic, with liming on demand, the proportion of acidic (pH < 5.0) soils will decrease from 9,8 to 6,1 %, and the proportion of soils poorly supplied with calcium will decrease from 18,1 to 12,9 %; 2 – the inertial scenario is unacceptable, because with a long-term deficit of liming, 40 % of the requirement, the weighted average content of exchangeable Ca will decrease by 31 %, and the share of soils poorly supplied with calcium will increase to 44,9 %, which will lead to a decrease in the yield of the most valuable crops: sugar beet, rapeseed, wheat and corn.