University of South Bohemia in České Budějovice

Biological invasions are reshaping aquatic food webs through novel interactions, yet how invaders integrate cross-ecosystem resources along estuarine gradients remains poorly understood. We used stable isotopes of carbon (δ13C), nitrogen (δ15N) and sulphur (δ34S) to characterise isotopic niches of a large decapod community along a 3-km gradient in a small Atlantic estuary in southern Iberia. The lower sector (i.e. at the river mouth) supported a native crab assemblage (Carcinus maenas, Afruca tangeri and Pachygrapsus marmoratus) co-occurring with the invasive Atlantic blue crab (Callinectes sapidus), whereas the upstream freshwater sector was dominated by the invasive red swamp crayfish (Procambarus clarkii); both invaders overlapped spatially in the brackish ecotone. A shift in the origin of assimilated resources over ≤ 1 km was noted, from marine- to inland-derived, and δ34S integrates patterns consistent with ontogenetic blue crab migration. Moreover, isotopic relationships (δ15N and δ34S) suggest an important contribution of prey migrating from downstream in the diet of the decapods inhabiting upper reaches. Bayesian ellipsoid volumes in δ13C–δ15N–δ34S space indicated that the blue crab exhibited the largest isotopic niche, particularly in the brackish sector and substantially larger than that of the invasive crayfish. In the lower sector, crab species showed niche segregation, except for Afruca tangeri and Carcinus maenas, which exhibited substantial overlap. In the brackish sector, blue crabs displayed higher δ15N and δ34S values than the crayfish, and the crayfish niche was largely encompassed by that of the blue crab but not vice versa, suggesting asymmetric interactions. Both invaders showed clear ontogenetic shifts. Blue crab niche peaked in juveniles, and suggests an important change in habitat and resource use through ontogeny. Crayfish niche indicated a dietary change towards greater plant/detritus intake in adults, but exhibited less variable diet than the blue crab across life stages. Overall, these results describe consistent taxonomic, spatial and ontogeny-dependent isotopic patterns in estuarine food webs invaded by large decapods.

Biochar is widely recognized for its potential to enhance soil microbial activity and immobilize toxic heavy metals. However, its large-scale adoption is limited by inconsistent performance and high market costs (320 to 800 € m−3). Here, we present a cost-competitive strategy for the industrial-scale production of exfoliated biochar from phytowaste feedstock and its robust validation in soil–microbial systems. Exfoliated biochar was continuously manufactured at pilot-to-industrial scale and evaluated across multiple independent trials using representative agricultural soils. Its performance was systematically benchmarked against virgin biochar in terms of microbial metabolic activation and immobilization of environmentally relevant heavy metals (Cu2+, Cr6+, and As3+). Across all validation sets, exfoliated biochar consistently promoted higher microbial metabolic activity and superior metal adsorption efficiency, demonstrating both reproducibility and process robustness. These enhancements are attributed to increased surface area, optimized pore architecture, and improved accessibility of reactive functional groups introduced during exfoliation. Molecular dynamics simulations combined with radial distribution function analyses revealed distinct adsorption mechanisms, including preferential interactions of hydroxyl (–OH) groups with Cr6+ ions and pyridinic nitrogen sites with Cu2+ ions. Complementary spectroscopic analyses further identified aliphatic hydrocarbons, aromatic domains, aromatic C=C bonds, and hydrogen-bonded –OH groups as major contributors to adsorption performance. Overall, this study demonstrates that industrially scalable exfoliation, coupled with targeted structural and functional optimization, enables reproducible enhancement of biochar–microbe–metal interactions. This approach provides a robust, systems-oriented pathway for sustainable soil remediation and biomanufacturing-relevant environmental applications.

As biostimulants have become a strategic tool for sustainable crop production in the face of changing environmental conditions, there is a continual demand for the development of innovative and more effective formulations. A novel approach that utilizes plasma treatment to enhance the extraction process in biostimulant production has recently emerged. This study investigated the plant-based biostimulant (prepared from horsetail, dog rose, and soapwort) and the potential of using gliding arc cold plasma (GA) and low-pressure microwave (MW) discharges to improve its efficacy. The experiment evaluated the effects of untreated versus plasma-treated biostimulants on soybean plant growth and vitality while elucidating their mechanisms. The results revealed that biostimulant application had a positive effect (p < 0.05) on different microbial groups in the soil. The treated plants presented greater root length and biomass (p < 0.05) as well as increased shoot height (p < 0.05). Generally, treatment with biostimulants increased lignification, as reflected by higher acid detergent fibre (ADF) and acid detergent lignin (ADL) fractions, as well as elevated peroxide levels, total isoflavone content, and antioxidant potential of plants measured by DPPH and ABTS assays. All biostimulants strongly upregulated the pathogenesis-related protein genes CHIA1 (encoding chitinase A1) and GLU (encoding β-1,3-glucanase) in the leaves of soybean plants. Elevated expression of selected genes related to jasmonic acid (JA) biosynthesis, mitogen-activated protein kinase (MAPK) signalling, cellular detoxification, and redox homeostasis was also observed. Overall, all the tested biostimulant variants improved the growth parameters of the soybean plants. Biostimulant application triggered complex defence responses involving changes in gene expression, antioxidant potential, secondary metabolite levels, and cell wall composition. The formulation generated by GA outperformed the other tested variants (MW discharge and untreated biostimulants), highlighting the potential of this technology to enhance biostimulant efficacy.

The non-native invasive American blue crab Callinectes sapidus Rathbun 1896 is spreading across the Mediterranean Sea, endangering native communities, fisheries, and aquaculture. Yet, knowledge on its predation efficacy in the non-native range remains limited, and little is known about potential sex-specific differences in functional responses. This study presents the first functional response analysis of C. sapidus outside its native range, comparing male and female crabs preying on the Mediterranean mussel Mytilus galloprovincialis Lamarck 1819. Females showed a higher proportion of killed mussels, and a higher proportion of eaten mussels at lower prey densities. Both sexes exhibited a type II functional response, with high attack rates and short handling times, indicating destabilizing effects on prey populations, as observed in other invasive crabs. While attack rates and handling times did not significantly differ between sexes when considering total prey killed, females showed higher attack rates when considering only eaten prey. This result reflects density-dependent differences in prey consumption, whereby females fully exploit prey more frequently at low prey densities. Functional Response Ratios revealed that female crabs exerted more than twice the predatory pressure of males. These findings are consistent with the greater energetic requirements of adult female blue crabs associated with reproduction and migration and demonstrate how incorporating sex-specific comparisons can improve predictions of the impacts of non-native species.

This study explores the impact of artificial intelligence (AI) on the labour market, focusing on changes in job roles, skill requirements, and human resource (HR) practices. Unlike previous surveys that primarily addressed technological aspects, this research systematically integrates technological, organisational, and institutional perspectives. The literature review (2020–2025) shows that AI adoption is closely associated with rising demand for technical and interdisciplinary skills, restructuring of work roles, and widening wage gaps between AI-skilled and non-AI-skilled workers. At the same time, many jobs are not eliminated but transformed, as AI frequently functions in augmentation rather than pure substitution mode. The results suggest that the future of work in the AI era will be determined less by technology itself than by how organisations, institutions, and policies govern its implementation.