Reuse of natural materials from gravel and sand mining for agricultural land reclamation

In Slovakia, temporarily taken agricultural land must be reclaimed and used again for crop production (Government Decree No. 58/2013). The aim of this study was to reclaim the land degraded by gravel and sand extraction, and to ensure that the reclaimed land has similar soil properties to the neighbouring arable land. To determine the extent of land reclamation, the morphological, basic physical, and hydro-physical soil properties, soil texture, and structure were compared between reclaimed land and the surrounding arable land. The soil properties were analysed in samples taken from five soil pits, and in four composite samples taken with a soil auger. We classified the reclaimed soil as Antrozem recultivated (according to the Slovak Soil Classification) and the adjacent arable (control) soil as Fluvizem cultivated saturated. The residual soil material obtained by flushing the excavated stony soil substrate was used for the land reclamation. The results showed that this material is suitable for soil reclamation, because it did not negatively affect the plant growth on the reclaimed land. We recommend using this waste material routinely for soil reconstruction/reclamation. One year after starting the reclamation, the differences in soil physical properties between the representative Fluvizem cultivated saturated and the Antrozem recultivated were negligible, indicating that the reclamation of soil physical properties was complete. Soil structure of the Antrozem recultivated showed a slight improvement trend one year after the reclamation. However, it still did not reach the level of the Fluvizem cultivated saturated used as a control. Therefore, it is necessary to improve soil structure primarily by the supply of organic fertilizers, as organic matter is one of the most important factors for the formation and stabilisation of soil aggregates.