With increasing demand for sustainable production, the need to effectively utilise site-based resources increases. One such resource is the remaining crop residues, both above and below ground, after harvest. In order to assess the magnitude of this resource, this study determined the plant nutrient contribution of residues from 17 different crops in seven different regions of Slovakia over a nine-year period. The soil profile 0.0–0.3 m was taken into account at belowground residues sampling. The results showed that winter rape, mustard, corn maize, triticale, winter rye with straw and sunflower left the most residues, exceeding 8 tons of dry biomass per hectare. Root crops (sugar beet, potatoes) and peas left less than 3 tons of residual dry biomass per hectare. Using these data, the nutrient potential coefficient, i.e. the amount of nutrients left by production of one ton of the main product was calculated by polynomial regression. With these coefficients and the known yield of a given crop, it was possible to calculate how much nitrogen, phosphorus and potassium each crop leaves in the soil after harvest. It was found that the amount of nitrogen left ranged from 20 to 132 kg, phosphorus from 2 to 24 kg and potassium from 13 to 218 kg per hectare. This has to be taken into account when calculating the fertiliser requirement of the subsequent crop in order to achieve better resource utilisation, thereby reducing the risk of eutrophication and improving farm profits by reducing expenditure on fertiliser.

Reduced tillage and no-till farming technology is possible to employ only under particular soil conditions. The total land area of sites in Slovakia that are available for the application of reduced tillage is approximately 25.3% of agricultural land (20.4% very suitable and 4.9% less suitable), while 74.7% of soils are not suitable for this technological approach. Only 19.8% of soils (17.8% very suitable and 2.0% less suitable) are suitable for no-till farming technologies of soil preparation before sowing, while 80.2% of soils are not suitable for this method. The best conditions for these approaches are found in soil types such as Chernozems, Cutanic Luvisols, Mollic Luvisols, and Fluvisols, but also Albic Luvisols and Regosols located on plains, in lowland areas, and in lower altitude basins. In the higher altitude regions, we do not recommend employing these technologies. The identification of areas suitable for this method is possible using the information in the databases of the Soil Science and Conservation Research Institute in Bratislava, which have been managed in this study using a geographic information system. The input parameters were the altitude of a given locality, as well as the slope steepness, depth, stoniness, and texture of the soil. It turns out that GIS is also an appropriate means for identifying and categorizing landscapes and agricultural lands in order to implement differentiated (reduction) cultivation systems.