In this study, we aimed at understanding a relation between PAH accumulation in the soils of brownfields that differed in origin (i.e., waste after coal mining, power plant, zinc–lead- or iron-ore processing) and age (400 years old to present). PAH contents were determined after their extraction with 2-propanol using a gas chromatograph (GC) equipped with a flame ionisation detector (FID) and a FactorFour VF-5MS capillary column. Sources of PAHs were identified using positive matrix factorisation (PMF). In regard to the relevance of the variables that helped explain the PAH accumulation, a random forest (RF) method was used. PMF analysis highlighted the connection of PAH sources with the industrial activity performed in the area. PAH concentrations increased with the age of tailings, but always exceeded the threshold-effect levels, indicating their potential to cause harm to humans. The RF method showed that for 2–3-ring PAHs the most important factor was the carbon content followed by clay, site, depth, pH, and then nitrogen, while for other PAHs, only the N content and depth exceeded 50% importance. PAHs’ vertical distributions reflected the history and the time passing from the brownfield site formation. Severe contamination of the brownfield soils indicates the necessity for remediation measures, especially where there are plans to build on these areas.

Plants, particularly edible species, are endowed with both nutritional and medicinal properties which, when properly harnessed, can contribute significantly to disease prevention, treatment, and the overall improvement of human health and well-being. This study explores the traditional knowledge and practices of local communities in the municipality of Quitexe, Angola, focusing on the use of edible plant species believed to possess therapeutic attributes. The primary objective was to document plant species with nutritional and medicinal potential. An ethnobotanical survey was conducted between September 2023 and April 2024 among 287 local inhabitants, using semi-structured questionnaires to collect qualitative and quantitative data. A total of 57 plant species were identified, distributed across 30 botanical families. The Fabaceae family was the most represented, accounting for 7 species, while leaves were the most commonly used plant parts (43.62%). The predominant method of preparation was decoction (24.32%), and the primary route of administration was oral (77.78%). Among the various health conditions treated with these plants, anemia was the most frequently cited ailment (11.97%). The results provide a valuable repository of local knowledge regarding plant-based nutritional and therapeutic resources. This foundational database has the potential to guide future investigations in phytochemistry, pharmacognosy, and biomedical research, supporting the development of plant-based products adapted to modern health and dietary practices. We argue that the sustainable and scientifically informed use of plant resources can play a vital role in integrating traditional remedies into contemporary healthcare systems, dietary practices, and nutritional supplementation strategies.

The present study aimed to assess the allelopathic potential of four cereals: winter wheat (Triticum aestivum L.), triticale (×Triticosecale Wittm.), spelt wheat (Triticum spelta L.) and barley (Hordeum vulgare L.) through a completely randomized (CR) design. The allelopathic effects of water extracts of different parts of the cereal plants (stem, leaf, and spike) at different concentrations (0.5%, 1.0%, 2.0%, and 4.0%) were evaluated on the seed germination and seedling growth. The germination rate, length, and dry weight of the shoot and root of the seedlings were measured. Ferulic acid was detected in all the cereals. The water extracts at 2.0% and 4.0% concentration had an allelopathic effect on the germination rate, shoot and root length of seedlings of spelt wheat, barley, and triticale, and the stem and leaf extracts affected the root and shoot length of winter wheat. The allelopathic effect of the dried powder of the cereals were evaluated in pot experiments. Both spelt wheat and triticale powder treatment at elevated CO2 levels increased the dry weight of the root, as well as the length of the shoot and root of winter wheat. Furthermore, treatment with 4.0 g of dry cereal powder combined with an elevated level of CO2 increased the shoot length, whereas the root length of winter wheat was unaffected. In summary, the combination of dry cereal powder with elevated CO2 stimulates the initial growth of winter wheat.

The aim of this study was to evaluate the adaptability of different genotypes of cowpea (Vigna unguiculata L. Walp.) in the edaphoclimatic conditions of a semi-arid region. In the experimental design, a completely randomized split-plot (2 × 8), with 3 repetitions (blocks) was used. The experiment comprised 7 new genotypes and 1 local genotype as the first main factor and application of insecticide as a secondary factor. Two-factor analysis of variance (two-way ANOVA) determined the differences between the treated and untreated plots. The results obtained in the experiment showed that the introduced genotypes V3 (IT07K-181-55), V7 (H4), and V5 (IT97K-556-4M) adapted well to the edaphoclimatic conditions of the study area and their yields were respectively 1019, 1015, and 841 kg/ha of grains in treated plots and 278, 517 and 383 kg/ha in untreated plots. Multivariate analysis revealed that the most important parameter was the germination rate. Finally, the best yield was obtained with the genotype V3 (IT07K-181-55), subjected to the use of insecticide, and with the V7 (H4) genotype in untreated plants. The findings presented in this research should be useful in crop system agricultural programs, particularly in the terms of selection of cultivating systems suitable for high-yielding cowpea.

The soil organic matter (SOM) content and stability in natural gypsum soils and mining/industrial soils were compared to check the effects of selected soil properties (mainly macro- and microstructure) on SOM stability and determine whether the old brownfield soils regardless of being highly polluted with trace metals could store high amounts of SOM. The mining/industrial soils were 50–400 years old and so had been left sufficiently long for full self-restoration. Despite having very different origins, both natural and brownfield soils stored similar amounts of SOM and had similar pH values, calcium carbonate contents, and textures but differed in SOM stabilisation, which was expressed by higher C/N ratios, lower aggregate water resistance index, lower dehydrogenase activity, and greater areas of undecomposed or slightly decomposed plant residues in mining/industrial soils compared to gypsum ones. However, the differences diminished with time, and in the oldest (150–400 years) brownfield soils, these parameters were similar to those in natural soils. Multiple regression analysis indicated that under the study conditions, SOM amounts, besides CaCO₃ contents and dehydrogenase activity were also strongly affected by porosity and microaggregation. In the research we showed the role of degraded soils in the sustainable use of the environment.