Torrential rainfall regimes, among others, are the origin of accelerated soil erosion. The Spanish southeastern Mediterranean region is characterised by an arid climate regime affected by extreme erosion episodes with an important loss of sediments. Soil erosion effects are even more noticeable in areas where soil has been anthropically degraded, as in the mining district of Sierra Minera de Cartagena . The present research focuses on monitoring and mapping the changes in the sediment distribution of iron oxides and hydroxyl (OH ⁻ ) bearing minerals caused by a cold drop known in Spanish as 'DANA' in September 2019 on the Rambla del Beal . This short rambla is fed by sediments from its drainage basin and by mining residues, irrigating a wide agricultural area. When discharges overflow the rambla channel, residues spread over its floodplain and reach the ecological protected coastal lagoon Mar Menor . The objective of the study was mapping the mineral distribution of the mining materials eroded from the source areas and sedimented in Rambla del Beal during a DANA. The study was carried out using a pre‐ and a post‐DANA image from the Sentinel‐2 satellite. After masking vegetation, urban areas and water bodies, different band ratios (B4/B3, B11/B12, B8A/B6) and a Spectral Angle Mapper (SAM) classification were applied. Sediment deposits were identified in wider areas after the DANA. Iron oxides increased their extension by 11.08% in the central area (B3/B4 with R ² of 0.84) and hydroxyl‐bearing minerals increased by 8.95% in the Rambla del Beal 's headwaters (B11/B12 with R ² of 0.71). The SAM classification (with a 0.1 rad threshold and an overall accuracy of 87.33%) allowed the differentiation and classification of two ferric iron oxides (haematite and goethite) and one iron hydrous sulphate mineral (jarosite). Additionally, band ratio images were spatially overlaid with the soil land uses map layer of the cadastre in order to plot the land uses most affected by the transported sediments during the DANA. These results highlighted agricultural land as the areas (land uses) most affected by iron oxides deposition, as oxidation processes occur more rapidly in these areas. However, grassland and scrubland were the areas with the highest content of hydroxyl‐bearing minerals, as water is accumulated in these places, which favours hydrolysis reactions. Highlights: Torrential events can relocate large volumes of contaminated sediments from former mining areas. Sentinel‐2 allows monitoring mine waste iron‐sulphate changes caused by weathering alteration. Spatial mineralogical pattern in sediments is controlled by geomorphology and flood dynamics. The proposed digital image analysis allows mapping short‐term evolution of mine waste sediments.

This paper presents detailed mineralogical results together with a geochemical characterization for a sequence of six natural soil profiles. Bedrock samples (R series) and overlying soil samples (S series) were characterized. The soil profiles are distributed in a series of Paleozoic lithological units from lower Ordovician to upper Carboniferous in age (Iberian Massif, NW Iberia). The lithological influence on mineral properties and geochemical composition and, how different weathering may be occurring under very similar temperate and acidic conditions, have been studied. Field observations together with laboratory analyses were indicative of differential weathering. So, a series of selected chemical indices and relations were applied to clarify this assumption. The mineralogy was analysed by Scanning electron microscopy (SEM-EDS), X-ray diffraction (XRD) of rock powder and soil oriented aggregates. X-ray fluorescence spectrometry (XRF) and inductively coupled plasma mass spectroscopy (ICP-MS) were applied to analyse chemical composition. The first results showed how major elements, SiO2, Al2O3 and Fe2O3, slightly enriched in the soil profiles, are consistent with the dominant mineralogy: quartz, chlorite, muscovite and/or illite, together with kaolinite and albite. The bases K2O, Na2O, CaO and MgO are also coherent with mineral composition and experience little variation, but are gradually removed in the profiles. The mobility of major elements leads to a general loss of bases and, in general, a slight enrichment in silica and sesquioxides. SiO2 is enriched, firstly accumulated in soils and partially depleted by dissolution as colloidal form. Al2O3 in some soils is slightly less than in former rocks, so other physical processes are expected to take place, involving clay removal with consequent aluminium depletion too. A special emphasis has been given to albite coexisting with kaolinite, firstly supposed to be directly inherited from parent substrates when present, but finally the chemical index PIA shows it was mainly due to mineral alteration of plagioclases. The best correlations to explain the albite alteration and kaolinitization progress were obtained with chemical indices PIA, CIW, CIA and Al2O3/Na2O ratio. This together with mineralogical signatures, suggest that kaolinite is the result of gradual dissolution due to the acid hydrolysis of albite in such acidic environments, which may also be attributed to the organic matter influence.

Soils play a fundamental role in plant nutrition as primary sources of potassium (K) and magnesium (Mg), whose availability depends on soil properties and environmental conditions. The composition of major cations in the soil solution is governed by interacting factors, including soil texture, acidity, mineralogical composition, and seasonal variability during the growing cycle. This study examines the availability, mobility, and seasonal dynamics of K and Mg in the soil solution of seven naturally managed soils across four distinct periods of a complete growing season beginning in spring. An integrated field and laboratory approach was applied to assess the influence of clay mineralogy on K and Mg behavior and overall soil fertility. Seasonal soil samples were analyzed for mineral composition, total elemental chemistry, exchangeable cation pools, and soil solution chemistry. Total elemental concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS), and clay mineral assemblages were identified by X-ray diffraction (XRD), focusing on 2:1 clay minerals, mixed-layer phases, and hydroxy-interlayered minerals (HIMs). The soils were dominated by 2:1 and mixed-layer assemblages, including illite/smectite (Ill/Sm), mica/illite–vermiculite (M/Vm), and chlorite/smectite (Chl/Sm), as well as transitional HIMs such as hydroxy-interlayered smectite (HIS) and hydroxy-interlayered vermiculite (HIV). Exchangeable Mg (0.28–1.30 cmolc kg⁻¹) and K (0.12–0.97 cmolc kg⁻¹) occurred in relatively high amounts, with maximum base saturation values of 13.14% (Mg) and 4.55% (K). Soil solution concentrations ranged from 1.60 to 3.00 ppm for K⁺ and 0.90–1.70 ppm for Mg²⁺, indicating substantial mobility and enrichment from the solid phase. These findings demonstrate that 2:1 clay minerals and mixed-layer phases act as key reservoirs regulating K and Mg exchangeability and release under natural acidic conditions, thereby sustaining soil fertility and nutrient availability for plant uptake.

A multi-methodological approach that consists of the systematic integration of detailed mineralogical, micromorphological, and geochemical features has been used to characterize a number of heterogeneous siliceous Paleozoic materials including low- to very-low-grade metamorphic crystalline rocks and siliciclastic and other detrital materials Ordovician to Carboniferous in age. Included in the same sequence are black slates, quartzites, and shales with alternating beds of sandstone, mudstone, and, occasionally, intermediate coal beds. A set of complementary and sequential analyses was performed to confirm the primary mineral assemblages, particularly the presence of unusual secondary silicates in the clay fraction. The sequential mineralogical methods included microscopic petrographic analysis (MOP), scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS), and X-ray powder diffraction (XRPD). Major elements were analyzed by X-ray fluorescence spectrometry (XRF) and minor elements (in some cases) using inductively coupled plasma mass spectroscopy (ICP-MS). Mineral quantification was carried out using the Siroquant system which is based on the QXRPD Rietveld technique. The essential minerals are mainly represented by K-rich dioctahedral varieties of white mica (muscovite) or illite, Fe-rich chlorites (Mg-rich chamosites), plagioclases (albite), and quartz, occasionally with kaolinite or even gibbsite. Up to 12 trace minerals such as iron oxides and sulfides were identified in some assemblages. After performing a validation procedure, a high level of consistency was observed between the major element oxide percentages, inferred from the XRPD study, and the equivalent oxide proportions determined by direct chemical analysis. The strong linear correlation shows that the percentages of K₂O, Na₂O, and MgO are also consistent with the quantitative clay mineralogy. The abundance of albite and the presence of iron-rich chlorites, together with the identification of kaolinite and occasionally gibbsite, support the interpretation of these bedrock materials.

Forest fires pose a significant threat to rural areas, affecting ecosystems, property, infrastructure, and human lives. Effective post-fire management strategies are crucial for short-term ecosystem and community recovery. This study evaluated the effectiveness of three post-fire interventions in reducing soil erosion and runoff within a temperate Atlantic–transition climate, focusing on a shrubland hillslope near organic vineyards in Corullón, NW Spain, after a moderate-severity fire. The research aimed to (i) compare the effects of plowing, straw mulching, and no intervention (control) on post-fire soil recovery, and (ii) assess the cost-effectiveness and environmental impacts of these treatments. Ten experimental plots were randomly assigned to plowing (n = 4), straw mulching (n = 4), or control (n = 2). Seventeen rainfall events were monitored between 15 days and six months post-fire. Results showed no significant differences in erosion or runoff reduction among treatments. Natural vegetation recovery, assessed visually, was rapid across all plots, with erosion and runoff stabilizing within two months. These findings suggest that, under the specific conditions of this temperate climate and moderate fire severity, early intervention techniques may not be necessary. The study concludes that natural regeneration can be a viable and cost-effective post-fire management strategy in regions with favorable environmental conditions for soil recovery, potentially reducing the need for intensive interventions.

Ante la escasa disponibilidad de datos edáficos y su creciente demanda, ha surgido la Cartografía Digital de Suelos (Digital Soil Mapping, DSM), con la finalidad de generar mapas continuos de variables edafológicas. El presente tra­bajo tiene como objetivo elaborar una cartografía de las propiedades edáficas superficiales ―arcilla, arena, limo y materia orgánica― en la zona de Riello (León), mediante la aplicación del método DSM basado en el modelo scorpan. Para su desarrollo, se utilizaron datos edáficos procedentes de muestreos y perfiles, así como covariables ambientales representativas de los factores formadores del sue­lo. Con estos datos se realizó un análisis estadístico mediante regresión lineal múltiple (MLR), siguiendo un proceso de calibración y validación, obteniéndose el mejor modelo predictivo para cada variable, junto con sus residuos y error asociado. Los resultados muestran que la materia orgánica es la variable con mejor ajuste al modelo (R² > 0,50), mientras que el limo presenta el valor más bajo (R² = 0,37). En consonancia, el error cuadrático medio (RMSE) más bajo corres­ponde a la materia orgánica (2,06), y el más alto al limo (9,70). Finalmente, se ha concluido que, a pesar de sus limitaciones, la aplicación del modelo scorpan en la cartografía digital de suelos constituye una herramienta valiosa en áreas de estudio con pocos datos de suelos.