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Salt-affected soils have detrimental effects on agriculture and ecosystems. However, these soils can still be used for halophyte (salt-tolerant plants) cultivation using brackish and/or saline water. In this study, we employed soil technologies and mutualistic microorganisms as a sustainable strategy to improve the growth and reproduction of the halophyte Limonium algarvense Erben’s growth and reproduction under saline conditions. A microcosm assay was conducted under controlled greenhouse conditions to cultivate L. algarvense using a saline Fluvisol (FLU) amended—or not—with a Technosol (TEC). Plants were inoculated with the arbuscular mycorrhizal fungus (AMF) Rhizoglomus irregulare and/or a consortium of plant growth-promoting bacteria (PGPB), and they were irrigated with estuarine water. Soil enzyme analysis and physicochemical characterisation of the soils, collected at the beginning and at the end of the assay, were carried out. The physiological status of non-inoculated and inoculated plants was monitored during the assay for 4 months, and AMF root colonisation was evaluated. In FLU, only plants inoculated with the AMF survived. These plants had lower number of leaves, and shoot and root dry biomass than the ones grown in the TEC by the end of the assay. In the TEC, PGPB inoculation led to higher NDVI and PRI values, and AMF inoculation promoted higher reproductive development but not pollen fertility. The findings show that the combined use of soil and microbial technologies can be successfully applied to cultivate L. algarvense, suggesting their generalized use for other Limonium species with economic interest, while contributing to the sustainable use of marginal lands.

Imaging spectroscopy (IS) can identify target materials at both mineralogical and geochemical levels. Therefore, in environmental applications, it can be used to assess contamination derived from mining activities, moving from contamination sources along pathways to receptors as acid mine drainage (AMD). This can be based on the spectra of specific assemblages of minerals from spectral libraries, which can indicate pH values at the time of their generation and the subsequent acid-generating potential. Alternatively, field spectral measurements can be used as input data for mapping algorithms. This study presents a new methodological approach to improving the results for mapping contamination sources and pathways, by combining multisource spectra from both these approaches at different scales. In addition to the mineralogical libraries and field spectra already mentioned, additional end-member spectra that are extracted from IS data are used so as to highlight particular site phenomena otherwise undetected by the two previous approaches. The highly correlated spectra are then used as input to the Spectral Angle Mapper algorithm, to establish a map of local field spectra and also one from image end-members. The intersection of the two maps results in an improved map, assigned in terms of correlation ≥0.8 of mineralogical assemblages focused on AMD indicators. This methodology was tested in the abandoned S. Domingos Mine, in southeast Portugal's Iberian Pyrite Belt, with AMD caused by long-term exploitation of volcanogenic massive sulphide deposits. Data from the HyMap™ sensor covered the area, and field spectroradiometric measurements were undertaken and analysed for mineralogical and geochemical content. A flightline containing the open pit was processed according to the aforementioned methodology, focusing directly on the target of interest and minimizing errors. The final map displays the mineralogical assemblage correlations ≥0.8 of variable pH indicators, particu

Imaging spectroscopy (IS) can identify target materials at both mineralogical and geochemical levels. Therefore, in environmental applications, it can be used to assess contamination derived from mining activities, moving from contamination sources along pathways to receptors as acid mine drainage (AMD). This can be based on the spectra of specific assemblages of minerals from spectral libraries, which can indicate pH values at the time of their generation and the subsequent acid-generating potential. Alternatively, field spectral measurements can be used as input data for mapping algorithms. This study presents a new methodological approach to improving the results for mapping contamination sources and pathways, by combining multisource spectra from both these approaches at different scales. In addition to the mineralogical libraries and field spectra already mentioned, additional end-member spectra that are extracted from IS data are used so as to highlight particular site phenomena otherwise undetected by the two previous approaches. The highly correlated spectra are then used as input to the Spectral Angle Mapper algorithm, to establish a map of local field spectra and also one from image end-members. The intersection of the two maps results in an improved map, assigned in terms of correlation ≥0.8 of mineralogical assemblages focused on AMD indicators. This methodology was tested in the abandoned S. Domingos Mine, in southeast Portugal's Iberian Pyrite Belt, with AMD caused by long-term exploitation of volcanogenic massive sulphide deposits. Data from the HyMap™ sensor covered the area, and field spectroradiometric measurements were undertaken and analysed for mineralogical and geochemical content. A flightline containing the open pit was processed according to the aforementioned methodology, focusing directly on the target of interest and minimizing errors. The final map displays the mineralogical assemblage correlations ≥0.8 of variable pH indicators, particu