Effect of Fertiliser on Changes in Labile and Water-Soluble Forms of Humus in Short-Term Rotations

Abstract

Mobile (labile and water-soluble) forms of humus are one of the basic components of effective soil fertility and a precondition for high productivity of crop rotations. As a result of fermentation, these forms of humus are mineralised and take part in plant nutrition, and some of them, being included in mobilisation processes, transition into stable humus substances. Therefore, it is important to investigate agrotechnological factors for managing their dynamics and redistribution in the soil environment during the growing season of agricultural crops. The purpose of the study: to investigate the effect of complex application of mineral and organic (conventional and alternative) fertilisers on the change of water-soluble and labile forms of humus during the growing season of agricultural crops grown in short-term rotations. The following research methods were used in this study: field, laboratory-analytical, computational-comparative, mathematicalstatistical. Higher level of labile accumulation (359.59 mg kg-1 of soil) and water-soluble (11.69 mg kg-1 of soil) humus forms under winter wheat crops occur when the predecessor of the crop in the crop rotation is meadow clover. The application of N60P90K90 specifically for winter wheat and 40 t/ha of manure in the conventional fertilisation system of grain-grass crop rotation contributes to the formation of 529.07 and 20.20 mg kg-1 of soil of the organic substances under study. The application of N120P100K100 and 40 t/ha of manure for corn for grain yields 567.42 and 22.55 mg kg-1 of soil, and N90P90K90 and 40 t/ha of manure for potatoes yields 543.66 and 21.75 mg kg-1 of mobile compounds humus. The obtained research results can serve as a basis for the development of highly efficient environmentally friendly farming systems and can be used for further scientific research on the development of ways and directions for managing humus-forming processes in the soil environment