Long-term effect of crops and fertilization on soil eco-chemical state

The study on long-term effects of various crops and fertilization practices on soil eco-chemical state was performed in the complex of Planosols at the Warsaw University of Life Sciences – SGGW experimental station in Skierniewice. The study covered three experiments – Ex-1 (established in 1923; no organic fertilization, cereals as a crop), Ex-2 (established in 1992; farmyard manure application every 4 years, cereals as a crop) and Ex-3 (established in 1975; no organic fertilization, blueberries as a crop). Additionally, each experiment covered three mineral fertilization options, including no fertilization, NPK and CaNPK. Soil samples were taken from A-horizons in 2017 and analysed using standard procedures. The results demonstrate considerable influence of crops and fertilization practices on soil eco-chemical state. Both mineral and organic fertilizers positively affected sorptive capacity as compared to control and modified ionic composition of soil sorption complex. Lower exchangeable acidity and higher sum of exchangeable basis and base saturation were noted in fertilized soils and cereals as a crop as compared to controls. Under blueberries there was observed strong acidification of the soil, in particular in combination with NPK fertilizers, as evidenced by the highest exchangeable acidity, hydrolytic acidity, and the lowest base saturation. Liming partially neutralized acidifying effect of blueberries. Fertilization and crops also strongly influenced buffering capacity of the soils. Extremely low ability to neutralize acidic ions was noted in unfertilized soils, whereas the highest at plots fertilized with Ca. The highest ability to neutralize alkaline ions was typical for NPK fertilized soils under blueberries.