The Influences of Different Methods of Grassland Renovation on the Weight of Post-Harvest Residues and the Abundance of Selected Soil Nutrients

Abstract

In Poland, half of the grassland is neglected and requires renovation, which was the reason for starting this research project. The aim of this research was to study the grassland habitat of lowland central Poland that has water-deficient, slightly acidic mineral soil, in the years 2013–2016. Specifically, the impact of three methods of grassland renovation on the dry matter yield and the weight of post-harvest residues, as well as on the content of particular nutrient components in the soil, were determined. Three legume–grass mixtures were used for the renovation. The study shows that the method of renovation (ploughing, harrowing, and herbicide + direct sowing) did not have a significant effect on the dry matter yield nor on the weight of the post-harvest residues or the content in the soil of some nutrients. The highest yield was obtained from the “Original” mixture with 50% of legumes in the seed mix. After the renovation, 5.03–7.17 t·ha−1 of post-harvest residues were obtained (mainly grasses and roots of plants, 68.7–71.1%). After three years from renovation, the soil pH significantly decreased and the content of Ca and Mg increased, while the nitrogen, phosphorus, potassium, and Corg compounds remained at an unchanged level. The concentration of various forms of nitrogen, P2O5, K2O, Ca, and Corg decreased in the deeper soil layer (down to 60 cm).