Abstract
The aim of the investigation presented in this paper was to identify the suitable and less energy-demanding methods to loose the subsoil compaction instead of mechanical subsoil loosening. The experiments with lupines (Lupinus luteus L. and Lupinus angustifolius L.) and spring barley (Hordeum vulgare L.) were made on the sandy loam Stagnic Luvisol. The field was compacted by tractors MTZ-82 (total weight 4.84 megagram Mg) characterized by multiple tyre-to-tyre passing. Parameters such as plants biomass (shoots and roots) and the changes in soil physical properties, the bulk density and penetration resistance, were measured. The best results showed yellow lupine on six times compacted soil where the penetration resistance was 1 MPa lower than on sites planted with barley or narrow-leafed lupine and decreased also soil bulk density on 3- and 6-times compacted soil by 0.1 and 0.05 Mg m−3, respectively. At the same time, lupine growth increased soil penetration resistance on uncompacted fields. As the positive effect of ameliorative plants growing occurs mostly in the following year, when roots are decayed and biopores are formed, further investigations with lupines are needed.
Acknowledgments
The study was supported by Estonian Science Foundation grant No. 5418.