LONG-TERM CROP ROTATION AND CONTINUOUS CROPPING EFFECTS ON SOIL CHEMICAL PROPERTIES

Soil is the crucial element of the environment and sustainable agriculture calls for more attention to be paid to the influence of cropping systems on soil properties. During a field experiment on Luvisols (north-eastern Poland), the effects of crop rotation (CR) (potato ??? oats ??? fibre flax ??? winter rye ??? faba bean ??? winter triticale), and long-term continuous cropping (CC) of oats (49 years), rye (49 years) and triticale (24 years) on the content of soil organic carbon (SOC), total nitrogen (TN), the available forms of phosphorus (P), potassium (K), magnesium (Mg), boron (B), manganese (Mn), copper (Cu), zinc (Zn), and iron (Fe), the pH, the hydrolytic acidity and the exchangeable cations (Ca2+, Mg2+, K+, Na+) of the soil were investigated. Based on the results, the sorption capacity and the index of sorption complex saturation with alkalis were calculated. Soil analyses were performed after cereals harvest in 2016. The SOC soil content in oats fields under the CR and CC system was similar. The SOC soil in rye fields was lower and in triticale fields higher under the CR than under the CC system. The cropping system usually did not differentiate the contents of macronutrients or micronutrients in the soil. The CR system promoted the K accumulation in the soil, while the CC of oats and rye reduced the pH and increased the sorption capacity of soils. Studies have shown that the continuous cropping system usually does not cause deterioration of soil chemical properties if manure and mineral fertilisers are applied systematically. The results indicate the need to monitor the properties of soil, particularly the SOC content and the soil pH, regardless of the cropping system. Such measures are essential in the protection of the soil against degradation.