Earthworms (Metaphire guillelmi) enhance soil carbon and nitrogen cycling by alleviating the pH decline and inhibition of soil enzyme activity resulting from HCBD contamination.

Depth-dependent effects of vegetation restoration on soil quality in ion-adsorbed rare earth leach residues: Insights from soil functions

Impact of load frequency on the laboratory transfer function for subgrade soil rutting behavior

Eucalyptus residues derived biochar rather than direct return in maintain soil bacterial communities structure and functions

Differential responses of humic acid in different soil aggregates under microplastic stress.

Emerging contaminants and their influence on plants: An in-depth review.

Pika bioturbation alters soil microbial networks, reducing stability but enhancing soil functionality in alpine meadows

Microplastic diversity, risks and soil impacts: A multi-metric assessment across land-use systems.

Biochar is a multifunctional soil amendment that improves soil structure, enhances water-holding capacity, and contributes to carbon sequestration. However, the dose-response relationship between biochar addition and soil behavior remains underexplored, particularly at high application rates. In this study, fifteen soil-biochar mixtures were prepared with biochar mass fractions from 0 to 1 (fBC = 0-1) to evaluate in detail the changes induced in a Sicilian clay soil. The mixtures were investigated for pH, electrical conductivity, bulk density, water-holding capacity, and water activity (Aw). Biochar addition caused pronounced increases in alkalinity, porosity, and water retention, following nonlinear dose-response trends with clear thresholds beyond fBC ≈ 0.3-0.5. FT-IR spectroscopy revealed the progressive appearance of oxygenated and aromatic functional groups, accompanied by a reduction in signals from adsorbed water and native soil polar groups. Fast Field-Cycling NMR relaxometry provided molecular-scale insight into soil-water interactions. At high biochar contents, water proton T1 relaxation times were markedly lengthened, indicating a reduced overall efficiency of surface-driven relaxation. Correlation-time (τc) analysis further revealed the emergence of water populations with longer correlation times and a redistribution of relaxation pathways toward outer-sphere dominated mechanisms. Overall, the results indicate that biochar improves soil water retention not by strong surface adsorption but through effective pore-space storage, keeping water available for biological use. The combined spectroscopic and relaxometric approach establishes a direct link between molecular-level water dynamics and macroscopic soil properties, highlighting the value of FFC-NMR as a powerful tool for studying natural porous systems.

Urban areas often suffer from enduring environmental issues, including flooding, biodiversity loss, heat island effects, and air and soil pollution. The Miyawaki method of afforestation, characterized by dense planting of native species on remediated soil, has been proposed as a rapid, nature-based solution for restoring urban ecological function. This study aims to evaluate early-stage changes in soil health following Miyawaki-style microforest establishment in formerly redlined neighborhoods in Elizabeth, New Jersey. Specifically, it investigates whether this method improves soil permeability, carbon content, and microbial activity within the first three years of planting. Three microforests aged one, two, and three years were assessed using a chronosequence approach. At each site, soil samples from within the microforest and adjacent untreated urban soil (control) were compared. Analyses included physical (porosity, dry density, void ratio), chemical (total carbon), and biological (microbial respiration, biomass, metabolic rate, carbon use efficiency) assessments. Soil permeability was estimated via the Kozeny–Carman equation. Microforest soils showed significantly greater porosity (p = 0.015), higher void ratios (p = 0.009), and reduced compaction compared to controls. Soil permeability improved dramatically, with factors ranging from 5.99 to 52.27. Total carbon content increased with forest age, reaching 2.0 mg C/g in the oldest site (p < 0.001). Microbial metabolic rate rose by up to 287.5% (p = 0.009), while carbon use efficiency also improved, particularly in the older microforests. Within just one to three years, Miyawaki microforests significantly enhanced both the physical and biological properties of degraded urban soils, signaling rapid restoration of soil function and the early return of ecosystem services.

After a functional and immaterial reduction of urban soil to a two-dimensional surface, dominating the urbanism of the 20th century, over the last decades, soil has been progressively restored as a material, urban, and living element. This study proposes a comprehensive framework for assessing soil thickness within urban environments, emphasizing its threedimensional and multidisciplinary nature. The proposed framework conceptualizes soil as comprising three distinct strata: (1) the land surface, which underpins urban planning and zoning practices; (2) the living soil, a dynamic and biologically active stratum composed of various horizons and domains of pedology; and (3) the deep underground, comprising parent materials and geological formations typically studied by geologists. In urban contexts, these strata are subject to significant anthropogenic interference. In particular, the urban underground is often heavily constructed, accommodating basements, mobility networks, and technical infrastructure. The proposed framework is applied to the case study of Brussels and aims to foster a soil-sensitive approach among urban designers and planners, thereby enabling site-specific unsealing and soil restoration practices. The application to Brussels reveals key insights into the benefits and constraints of soil unsealing, particularly concerning the soil's function in water regulation. This study underscores the importance of considering soil in urban planning and offers a model for assessing the potential effectiveness of soil unsealing projects, ultimately promoting more resilient and sustainable urban environments.

Gabon, with nearly 22 million ha of forest, is the second most forested country in Africa and part of the Congo Basin. Its diverse geology affects soil functioning. This study assessed soil organic carbon (SOC), total nitrogen (TN) and carbon dioxide equivalent (CO₂eq) in rainforest soils from the granito-gneissic basement and coastal sedimentary basin of Gabon at depths of 0–30 cm. Bulk density, sand, clay, SOC (115.33 Mg C ha⁻¹), TN (9.83 Mg N ha⁻¹) and CO₂eq (417.52 Mg CO₂ ha⁻¹) were higher in the granito-gneissic basement, whereas pH and silt (33.3 %) were greater in the sedimentary basin. Despite very sensitive variabilities, the results present good evidence indicating a strong influence of lithology and vegetation cover on soil texture and nutrient richness. This study has identified for the first time the key elements to consider for sustainable soil carbon management.

Reductive soil disinfestation (RSD) is an effective approach for controlling horticultural plant diseases by improving soil properties. However, its effects on microbial communities and their functional characteristics across soil depths remain poorly researched. In this study, we evaluated the impacts of RSD using solid (rice bran, RB) and liquid (molasses, MO) organic amendments in a Fusarium-infested field. Changes in biotic and abiotic properties were examined at two soil depths (0–15 cm and 15–30 cm) and the potential of different amendments to restore microecological functions in deeper soil was assessed. Both RSD treatments alleviated soil acidification and salinization compared with the control. The absolute abundances of Fusarium oxysporum and Fusarium solani were significantly reduced under both treatments, with MO-RSD showing stronger pathogen suppression in the 15–30 cm layer. MO-RSD exerted a greater influence on microbial community structure across soil depths, resulting in bacterial-fungal co-occurrence networks with higher complexity. Metabolic activity and carbon source utilization increased significantly following both RSD treatments, with the greatest enhancement observed in the 0–15 cm layer under MO-RSD. Furthermore, MO-RSD enriched a higher diversity and abundance of beneficial microorganisms such as Bacillus, Paenibacillus, and Tumebacillus in the 0–15 cm layer, and Azotobacter, Penicillium, and Neurospora in the 15–30 cm layer. These microbes were closely associated with enhanced metabolic activity and pathogen suppression. Overall, MO-RSD established a more integrated and functionally diverse microbiota across the 0–30 soil profile, likely due to the greater permeability and mobility of liquid organic amendments in shaping deeper soil microbial communities.

The long-term monoculture of Eucalyptus plantations in southern China has raised ecological concerns, prompting a shift towards mixed-species plantations as a sustainable alternative. This study investigates the mechanisms by which companion tree species enhance soil functionality in subtropical red soil regions. A field experiment compared a pure Eucalyptus (CK) plantation with three mixed-species plantations: Eucalyptus × Mytilaria laosensis (A × M), Eucalyptus × Magnolia hypolampra (A × H), and Eucalyptus × Michelia gioii (A × X). Comprehensive soil analyses were conducted at three soil depths (0–20 cm, 20–40 cm, and 40–60 cm) to assess chemical properties, enzyme activities, and humus components, and soil organic carbon (SOC) molecular structure was characterized by Fourier-Transform Infrared Spectroscopy (FTIR), with the relationships quantified using structural equation modeling (SEM) to test predefined causal hypotheses. The results showed that A × H significantly boosted topsoil fertility (e.g., OM: 46.61 g/kg), while A × M enhanced the recalcitrant organic carbon (ROC: 35.29 g/kg), indicating superior carbon sequestration potential. The FTIR analysis revealed species-specific alterations in SOC chemistry, such as increased aromatic compounds in A × H/A × X. The SEM analysis demonstrated that the latent variable “Humus” (reflected by LOC and ROC) directly and positively influenced the latent variable “Soil Fertility” (reflected by pH, OM, and AP; path coefficient: 0.62). In contrast, the latent variable “Organic Components” (reflected by specific FTIR functional groups) exhibited a significant direct negative effect on “Soil Fertility” (−0.41). The significant pathway from “Organic Components” to “Enzymatic Activity” (0.55*) underscored the role of microbial mediation. The study concludes that mixed plantations, particularly with Mytilaria laosensis (A × M), improve soil health through an “organic input–microbial enzyme response–humus formation” pathway, offering a scientific basis for sustainable forestry practices that balance productivity and ecological resilience.

IntroductionThe spatial heterogeneity introduced by strip tillage (ST; maize belt (ST-M) and straw belt (ST-S)) leads to the pronounced differentiation in soil properties. However, its effects on soil microbial community structure and function remain unclear.MethodsIn this study, amplicon sequencing (Accu16S™ and AccuITS™) was used to investigate the effects of different tillage practices on soil microbial communities.ResultsThe results showed that the ST and ST-S treatments significantly increased the Shannon diversity index of microbial communities compared to rotary tillage (RT). Tillage practices also influenced microbial community structure, with fungal communities showing a more pronounced response than bacterial communities. Compared to the RT treatment, the ST-M, ST-S, and ST treatments significantly increased the relative abundance (RA) of Gemmatimonadetes and reduced the RA of Acidobacteria. Additionally, the ST-S and ST treatments significantly enhanced the absolute abundances (AAs) of Arenimonas and Luteolibacter compared to the RT treatment. Following freeze–thaw events, the ST-M, ST-S, and ST treatments significantly increased the AAs of Latescibacteria, while significantly increasing the AA of Microvirga compared to the RT treatment. Furthermore, Mantel test showed that soil bacterial communities were significantly correlated with electric conductivity (EC) and available potassium, while soil fungal communities were significantly correlated with EC and soil organic carbon. Functional prediction revealed that ST significantly promoted nitrification, denitrification, sulfur oxidation, and ectomycorrhizal.DisscussionTherefore, strip tillage could improve microbial community diversity and microbial regulation of the N and S cycles in black soil, providing a microbiological perspective for conservation agriculture.

Background: Soil contamination by heavy metals and pesticides remains a persistent global challenge with far-reaching consequences for agricultural productivity, ecosystem stability, and human health. Despite extensive research, existing studies remain fragmented across soil science, toxicology, and environmental health, limiting efforts to integrate soil nutrient status, contaminant dynamics, and their implications for plant stress, food-web integrity, and environmental well-being. Objectives: The review aims to conceptualize and critically evaluate advancements in soil nutrient dynamics, pollutant toxicology, and remediation strategies, with emphasis on heavy metals and pesticides. It integrates soil ecological processes, plant stress responses, environmental toxicology, and human health within a unified “One Health” perspective. Methodology: This review employs a focused yet transparent evidence-mapping approach – short of a holistic protocol but still structured and traceable under PRISMA – to integrate soil profiling, contaminant toxicology, and sustainable remediation within the One Health framework. Through a targeted literature search using defined inclusion criteria and multidisciplinary keywords, the review critically evaluates soil nutrient dynamics, toxicological pathways of heavy metals and pesticides, and emerging mitigation strategies while identifying key knowledge gaps relevant to sustainable agroecosystem management. Results: Soil functions as a complex biogeochemical system whose fertility, nutrient cycling, and ecosystem services depend on the interplay between organic matter, microbial communities, and physicochemical properties across soil horizons. Anthropogenic pressures – industrial emissions, mining, waste disposal, agrochemicals, and excessive fertilization – introduce heavy metals and pesticides that disrupt nutrient dynamics, degrade soil structure, impair microbial processes, and trigger plant physiological stress. Evidence demonstrates that agrochemical overuse destabilizes soil microbial ecology and nutrient–microbe interactions, causing contamination, reduced biodiversity, nutrient imbalance, and increased risks to food security and environmental quality. Integrating these findings reveals that soil health is tightly linked to contaminant behaviour, plant–soil interactions, and ecosystem resilience, emphasizing the need for sustainable management and remediation strategies to preserve soil-based ecosystem services. Conclusion: Heavy metal and pesticide contamination undermines soil functioning, plant productivity, ecosystem stability, and public health, reaffirming that soil integrity is a core component of the “One Health” continuum. Evidence indicates that while physicochemical remediation offers rapid mitigation, biologically driven and green-chemistry approaches – such as biochar, phytoremediation, and microbial degradation – provide more sustainable, scalable, and ecologically restorative solutions. Advancing soil health and sustainable agriculture requires interdisciplinary collaboration, long-term field research, integrated contaminant modeling, and globally harmonized regulatory frameworks to safeguard ecosystems, food security, and human well-being.

The increasing challenges posed by climate change demand holistic approaches to mitigate ecosystem degradation. In Mediterranean-type regions—biodiversity hotspots facing intensified droughts, fires, and biological invasions—such strategies are particularly relevant. Among invasive species, Acacia longifolia produces substantial woody and leafy biomass when removed, offering an opportunity for reuse as soil-improving material after adequate processing. This study aimed to evaluate the potential of invasive A. longifolia Green-waste compost (Gwc) as a soil amendment to promote soil recovery and native plant establishment after fire. A field experiment was carried out in a Mediterranean ecosystem using Arbutus unedo, Pinus pinea, and Quercus suber planted in control and soils treated with Gwc. Rhizospheric soils were sampled one year after plantation, in Spring and Autumn, to assess physicochemical parameters and microbial community composition (using composite samples) through Next-Generation Sequencing. Our study showed that Gwc-treated soils exhibited higher moisture content and nutrient availability, which translated into improved plant growth and increased microbial richness and diversity when compared with control soils. Together, these results demonstrate that A. longifolia Gwc enhances soil quality, supports increased plant fitness, and promotes a more diverse microbiome, ultimately contributing to faster ecosystem recovery. Transforming invasive biomass into a valuable resource could offer a sustainable, win–win solution for ecological rehabilitation in fire-affected Mediterranean environments, enhancing soil and ecosystem functioning.

Engineered biochar (EngBC), a modified form of traditional biochar, offers a promising solution for agricultural sustainability. Tailored through physical, chemical, or biological treatments, EngBC is optimized for specific applications to improve soil health and function. This review synthesizes research on its key benefits, including enhanced soil fertility, water retention and pH moderation. EngBC also acts as an effective slow-release fertilizer, improving nutrient use efficiency while reducing leaching and contributes to climate mitigation through carbon sequestration. Despite these advantages, the transition to widespread practice faces considerable hurdles. High production costs, a lack of standardized protocols and potential environmental risks from contaminants or nanoparticles currently limit its adoption. A critical knowledge gap exists due to the scarcity of long-term field studies needed to validate its efficacy and safety under real-world conditions. Future research must prioritize systematic field investigations, robust risk assessments and a deeper understanding of its ecological impacts. Addressing these areas is essential for developing guidelines to enable the safe, effective and sustainable integration of EngBC into modern farming systems.

Sustainable agricultural production must be aligned with environmental and biodiversity goals. Foliar selenium (Se) application can effectively increase the rice Se content; however, its long-term effects on soil microbial diversity and functional changes remain poorly understood. Therefore, we conducted a field experiment (foliar Se for 3 years), a simulation experiment (simulated foliar Se for 5 and 10 years), and a meta-analysis (effects of exogenous Se application on the soil microbial α-diversity) to evaluate the effects of foliar Se application on rice production and soil microbial communities and functions. Foliar Se application for 3 years effectively increased the grain Se content, increased soil Se and organic carbon levels, and altered root energy secretion metabolites with significant increases in glutamic acid and glutamine. Soil Se application did not affect the organic carbon content. Continuous foliar Se application for 3 years reduced the stability of the microbial community, with root exudate metabolites exerting stronger effects than Se. The meta-analysis indicated that high-concentration Se (≥0.4 mg·kg-1) significantly reduced the Shannon index of microbial communities. Treatment with Na2SeO3 (for 10 years) increased the soil Se content by 132.67% while decreasing microbial α-diversity findings that align with the meta-analysis results. However, treatment with the compound fertilizer containing Na2SeO3 (for 10 years) increased the soil Se content by 187.43% yet significantly enhancing microbial α-diversity. This discrepancy may be attributed to the oxides formed by iron and manganese ions in the compound fertilizer, which reduce the bioavailability of Se in the soil. Both field and simulation experiments confirmed that the exogenous Se application accelerated the transformation of soil organic phosphorus to an inorganic state soil available phosphorus content, which increased by 52.41% and 5.09%-72.10%, respectively. Denitrification in the soil nitrogen cycle was strengthened, and the increased abundance of norC and nosZ enhanced the possibility of N2O emissions. These results indicate that long-term foliar Se application increases the soil Se content, reduces soil microbial diversity, and strengthens microbial denitrification, which is detrimental to sustainable agricultural production.

Heavy-metal (HM) contamination undermines soil functions and food safety, while risk appraisals often rely on chemical indices that can be unstable in the presence of extremes and only indirectly reflect biological integrity. We present an integrative framework that couples standardized contamination metrics with soil microbiome profiling to deliver stable, interpretable classifications and actionable bioindicators. Twelve peri-urban soils from Southern Italy were analysed for potentially toxic elements, including Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb), and Zinc (Zn) and profiled by shotgun metagenomics. We introduce a Standardized Ecological Risk index (SPERI) that preserves the ranking conveyed by conventional composites yet reduces outlier leverage. SPERI strongly agreed with Improved Potential Ecological Risk Index (IPERI) while stabilizing variance (R² = 0.896) and improved between-site comparability. Along the contamination gradient, community structure shifted consistently: families such as Pseudomonadaceae, Xanthomonadaceae and Rhodospirillaceae increased with risk, whereas Geodermatophilaceae and Nocardiaceae declined. Simple decision-tree models trained on family-level relative abundances reliably separated SPERI classes and repeatedly selected Zn- and Cd-enriched sites as primary split drivers, aligning microbial signals with chemical risk. By combining open, reproducible analytics with jointly chemical- and microbiome-informed endpoints, this workflow improves the interpretability and transferability of ecological risk assessment and supports targeted remediation and monitoring in contaminated agro-ecosystems.