Impact of alfalfa and NPK fertilization in agricultural reclamation on the transformation of Technosols in an area following lignite mining

Abstract

Open‐cast mining of lignite leads to considerable degradation of the natural environment, which then must be reclaimed. The aim of this study was to assess the transformation of Technosols in an area after lignite mining which had been under 40‐year cultivation of alfalfa with grass at various NPK fertilization rates. We hypothesized that 40‐year cultivation of plants caused morphological transformation of the parent material and resulted in differentiation of physical and chemical properties in the profile of the Technosols; fertilization had an added advantageous effect on their properties. The surface layer was transformed into an Ap‐horizon. Under alfalfa, with grass and NPK fertilization, Ap‐horizons demonstrated lower bulk density (BD) (7–11%) and particle density (PD) (1–2%), and higher total porosity (TP) (18–35%), drainable porosity (DP) (2–94%), field water capacity (FC) (11–21%), unavailable water (UW) (4–17%), soil organic carbon (SOC) (80–142%), total nitrogen (TN) (261–330%), available P (39–435%), available K (32–89%), cation exchange capacity (CEC) (25–43%), and soil acidity (Hext) (42–81%) compared to Cd‐horizons. Fertilized Technosols (1NPK, 2NPK), compared with control (0NPK), showed in the Ap‐horizon an increase in SOC (18–35%), TP (8–15%), DP (81–90%), FC (9–10%), P (110–285%), K (14–71%), and TN (0–18%), and a decrease in BD (4–7%). In contrast, fertilization had no effect on the UW, PD, soil inorganic carbon (SIC), CaCO3, available Mg, and pHKCl. The alfalfa and orchard grass played a key role in the reclamation and soil‐forming processes, while fertilization played a supporting role.

Nitrogen recovery in reclaimed mine soil under different amendment practices in tandem with legume and non‐legume revegetation: A review

“…NPK-fertilized coal mine spoils which were under legume (Medicago sativa) and grass (Dactylis glomerata) revegetation for 40 years demonstrated 18% more total N compared with control. The authors concluded that grasslegume seeding plays a primary role in the reclamation processes, while NPK fertilizer application plays a supporting role (Otremba et al, 2020). 4.1.4 | Topsoil amendment Amendments like topsoil have been considered extensively in mine-degraded areas where the native soil is badly damaged.…”

Germination and sustainable cultivation of succulent halophytes using resources from a degraded estuarine area through soil technologies approaches and saline irrigation water

“…This soil management technique has been used to reclaim degraded soils in microcosm studies (Abreu & Magalhães, 2009; Cortinhas et al, 2020; Cortinhas et al, 2021; Fourvel et al, 2019; Macía et al, 2014; Otremba et al, 2021) and field, in mining context (Arán et al, 2021; Asensio et al, 2013). Nonetheless, there are only a few reports on this technique applied to degraded Mediterranean estuarine environments (Cortinhas et al, 2020; Cortinhas et al, 2021), and none of them approach succulent halophytes cultivation.…”

“…Tailored soils construction is a sustainable technology that allows to improve the physical (e.g., aggregation), chemical (e.g., nutrients concentration), and biological (e.g., soil biota) soil properties (Santos, Abreu, Macías, & Magalhães, 2017;Séré et al, 2010). This soil management technique has been used to reclaim degraded soils in microcosm studies (Abreu & Magalhães, 2009;Cortinhas et al, 2020;Cortinhas et al, 2021;Fourvel et al, 2019;Macía et al, 2014;Otremba et al, 2021) and field, in mining context (Arán et al, 2021;Asensio et al, 2013). Nonetheless, there are only a few reports on this technique applied to degraded Mediterranean estuarine environments (Cortinhas et al, 2020;Cortinhas et al, 2021), and none of them approach succulent halophytes cultivation.…”

Small‐scale spatial variability of Technosol properties in a chronosequence of reclamation of dredged‐sediment landfills

“…Natural succession frequently fails to successfully reestablish the vegetation cover in sites heavily disturbed by mining (Ruggles et al, 2021) or occurs at slower rates than expected due to poor substrate conditions (Gilland & McCarthy, 2014). In mining waste deposits, active reclamation is often necessary to ensure a transformation of the mining waste into Technosols (“soils dominated or strongly influenced by human‐made material”; IUSS, 2014; Schad, 2018) and restore its utility or environmental value (Otremba et al, 2021). In Colombia, several approaches have been developed to reclaim dredged‐sediment landfills resulting from alluvial gold mining activities through reforestation and agroforestry (Castellanos Barliza & Leon, 2010; Mosquera et al, 2008; Thomas, 2014).…”