Soil contamination continues to threaten ecosystem health and agricultural productivity worldwide. However, rhizosphere-mediated bioremediation has emerged as a nature-inspired, sustainable approach for mitigating these impacts. This review advocates field-scale implementation of rhizosphere microbiome engineering by exploiting interactions among plants, microorganisms, and soil. Unlike previous reviews that primarily summarize rhizosphere-mediated remediation processes, it integrates mechanistic, ecological, and engineering perspectives to identify critical barriers limiting field performance. This review synthesizes recent advances in rhizosphere microbiome engineering, with an emphasis on root-exudate manipulation, synthetic microbial communities (SynComs), biochar-assisted remediation, and multi-omics technologies. The evidence reviewed indicates that root exudates are key regulators of microbial recruitment, biofilm formation, and expression of contaminant-degrading genes, while engineered microbial consortia enhance functional complementarity and pollutant transformation. A comparative analysis of laboratory and field studies reveals substantial performance gaps, with highly efficient degradation observed under controlled conditions often declining following field deployment because of microbial competition, environmental variability, and contaminant sorption dynamics. The review further shows that integration of SynComs with biochar carriers and precision root-exudate engineering can improve microbial establishment and remediation efficiency. Advances in metagenomics, metabolomics, and systems biology are enabling more predictive design and monitoring of rhizosphere processes. Collectively, this review provides a mechanistic synthesis, identifies key translational bottlenecks, and outlines practical directions for developing scalable rhizosphere-based remediation technologies.
Artisanal and small-scale gold mining (ASGM) is increasingly central to rural livelihoods in Zimbabwe amid unemployment and declining agricultural viability driven by climate change. However, in a context characterised by uneven access to technology, capital, and contested resource governance, ASGM assumes a socially differentiated and politically contested character with far-reaching implications for livelihood trajectories. Drawing on qualitative data from interviews, focus group discussions, and archaeological surface survey walks in Shurugwi, Zimbabwe, this article analyses how everyday mining practices, technological adoption, and socio-political relations shape livelihood dynamics. Using a historical materialist lens, the study shows that differential access to processing technologies and means of production structures participation and reward within the mining economy. Informal arrangements function as adaptive governance mechanisms regulating access to labour, markets, and claims amid regulatory ambiguity. Overall, ASGM emerges as a contradictory livelihood system that simultaneously enables accumulation, survival, and precarity, underscoring livelihoods as contested processes embedded in evolving socio-technical and political relations of production.
Chlorinated paraffins (CPs), complex polychlorinated alkanes, are persistent organic pollutants (POPs) of growing concern. They are used as flame retardants, plasticizers, and lubricants, and enter agroecosystems via wastewater irrigation, sewage sludge, atmospheric deposition, and industrial runoff, exhibiting strong sorption, long half-lives, and bioaccumulative potential. While short-chain CPs (SCCPs) are regulated under the Stockholm Convention, medium- and long-chain CPs (MCCPs, LCCPs) are increasingly detected in soils, sediments, and crops but remain poorly categorized for toxicity and environmental fate. Evidence indicates that CPs can alter soil microbial diversity, inhibit enzymatic activity, disrupt nutrient cycling, and accumulate in plants, posing risks of food-chain transfer and human exposure. However, significant knowledge gaps persist regarding their long-term ecotoxicological impacts, degradation and transformation processes, and interactions with soil organic matter that govern their mobility, persistence, and bioavailability. This review discusses the existing literature on CP occurrence, fate, and ecological effects in agricultural environments, emphasizing analytical techniques and monitoring approaches for assessing soil-plant-human exposure, and identifies key research needs. Addressing these gaps is essential for improving risk assessment, guiding regulatory development, and protecting soil health, crop productivity, and food safety. CPs represent a “silent contaminant” in agriculture, threatening soil health, crop productivity, and food safety. Future research should integrate advanced detection methods, pilot-scale remediation strategies, and comprehensive risk assessments to inform policy, protect vulnerable populations, and safeguard sustainable agricultural production.
The development of efficient, safe, and reversible solid-state hydrogen storage materials is essential for advancing a sustainable hydrogen-based energy economy. In this work, we present a comprehensive first-principles density functional theory investigation of the perovskite hydrides SiMgH3 and GeMgH3, focusing on their structural, dynamical, mechanical, electronic, optical, and hydrogen storage properties. Both compounds are found to be thermodynamically and dynamically stable, as confirmed by negative formation energies and phonon spectra free of imaginary modes. Mechanical analysis reveals that both hydrides are ductile and mechanically robust, with SiMgH3 exhibiting higher stiffness and stronger resistance to deformation compared to GeMgH3. Electronic structure calculations indicate metallic behavior with mixed ionic–covalent H–metal bonding, which enhances charge transport and supports reversible hydrogen mobility within the lattice. Optical properties further demonstrate strong dielectric response and efficient low-energy photon absorption, indicating favorable electronic polarization characteristics. Hydrogen storage analysis shows that SiMgH3 exhibits superior performance, with a gravimetric capacity of 5.46 wt This study shows that SiMgH3 and GeMgH3 are stable hydrogen-storage materials with good mechanical strength and electronic conductivity. SiMgH3 performs better, offering higher hydrogen capacity and a lower hydrogen release temperature, making it more suitable for practical applications.
PurposeThe target date to achieve the Sustainable Development Goals (SDGs) by 2030 is less than a decade; urban commercial solid waste in developing nations has elicited considerable concern. From previous studies, some policies on commercial refuse have been implemented, but the issue persists. The purpose of this study is to examine Sustainable Human Settlement (SHS) using Commercial Solid Waste (CSW) disposal systems to achieve SDG 11.Design/methodology/approachThis study engaged a multistage sampling technique to examine the types, quantities and impediments of CSW disposal practices. The market and three trades with the highest volume of refuse were selected via purposive sampling at the first and second stages, and random sampling at the third stage to identify the 15 lines that generated the most trash. A questionnaire was administered to 345 traders using systematic random sampling, and the data were analysed using inferential statistics. The diffusion of innovation theory (DoIT) and theory of planned behaviour (ToPB) constructs applied confirmed the theoretical gap.FindingsThe findings revealed that decomposable (84.85%) and non-decomposable (15.15%) refuse were generated daily (2,611.07 kg), weekly (13,055.35 kg) and 339,439.1 kg in the dry season. Tailoring materials generated the highest daily refuse (1,162.80 kg). Inadequate skips, poor funding, insufficient decision-making process, poor maintenance of facilities and scarce technical measures were identified as impediments to the CSW disposal system at the marketplace. DoIT and ToPB can be applied to enhance CSW disposal practices for SHS. Audit policy will help achieve SDG 11 across marketplaces in Nigeria.Originality/valueAs part of this study's implications, DoIT and ToPB will be used to improve SHS through the CSW disposal system at the Ahia-Ohuru market.
