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Graphene and its derivatives have attracted sustained research interest as adsorbent materials for environmental applications, driven by their large surface area, chemically tunable surface, and compatibility with a wide range of functional modifications. This review covers recent developments in the use of graphene-based materials for water, air, and soil remediation, focusing primarily on work published over the last five years. A concise overview of graphene, its derivatives, and other carbon nanostructures, such as carbon nanotubes and fullerenes, is also provided. The main graphene derivatives are briefly described (graphene oxide, reduced graphene oxide, graphene nanoribbons, and graphene quantum dots) together with a comparative overview of the principal synthesis methods, from mechanical exfoliation and chemical vapor deposition to liquid-phase exfoliation, oxidation/reduction, and flash Joule heating. The discussion then turns to how surface functionalization and composite formation affect adsorption performance in practice. In water treatment, the results are most developed: functionalized composites have reached adsorption capacities of 484.3 mg g⁻¹ for organic dyes and 157.23 mg g⁻¹ for Cr(VI). Air purification is a smaller but growing area, with plasma-treated graphene aerogels achieving CO₂ capture capacities of 3.3 mmol g⁻¹ and retaining performance over 40 cycles. Soil remediation remains the least explored compartment, though arsenic immobilization efficiencies of up to 99.3% have been reported. Remaining challenges around scalability, behavior in real environmental matrices, and long-term ecotoxicological impact are identified and discussed. Full article

To explore low-carbon spring wheat production strategies for the ecologically fragile Qinghai Plateau, a two-year field experiment was conducted using a split-plot design. The main plots were set with three nitrogen (N) application levels: N0 (0 kg·ha⁻¹, no N input), N1 (157.5 kg·ha⁻¹, 30% N reduction relative to conventional rate), and N2 (225 kg·ha⁻¹, the conventional rate). The subplots comprised four green manure mixed cropping patterns: sole cropped common vetch (CK), common vetch mixed with hull-less barley (HB), common vetch mixed with hairy vetch (HV), and common vetch mixed with rapeseed (RS). Averaged across green manure treatments, N1 reduced global warming potential (GWP) by 14.56% and greenhouse gas intensity (GHGI) by 16.89% compared with N2. Under the N1 treatment, compared with CK, RS reduced cumulative CO₂ emissions by 7.77% and GWP by 7.45%, maintained wheat grain yield comparable to those under N2, and obtained the minimum GHGI which was 2.92% lower than CK. Regarding soil properties, all green manure patterns significantly increased soil available phosphorus (AP) and available potassium (AK) compared with CK. Specifically, HB increased AP by 12.81% and AK by 16.38%, and RS also increased AP by 4.37% and AK by 2.36%. In addition, HB enhanced soil organic matter (SOM) by 5.85%, ammonium nitrogen (NH₄–N) by 8.13%, and nitrate nitrogen (NO₃–N) by 4.34%. Soil NH₄–N and NO₃–N were identified as key drivers of GHGI across treatments. On the Qinghai–Tibet Plateau, a 30% N reduction combined with target-oriented green manure mixtures—RS for emission mitigation and HB for high yield and fertility—offers a viable low-carbon strategy for spring wheat production. Full article

This study investigated the effects of drought during reproductive and boll development stages under elevated CO₂ conditions. A pot experiment was conducted in the Soil–Plant–Atmospheric-Research (SPAR) facility using the upland cotton cultivar DP 1646 B2XF grown under control (well-watered; 0.12 m³ H₂O m⁻³ soil) and drought (0.09 m³ H₂O m⁻³ soil) conditions at ambient (425 ppm; aCO₂) and enriched (725 ppm; eCO₂) CO₂ concentrations. Under drought stress, photosynthesis and stomatal conductance decreased by 35% and 63%, respectively, under aCO₂, whereas reductions were less pronounced under eCO₂ (20% and 36%). Under drought and aCO₂, intrinsic and instantaneous water-use efficiency increased by 74% and 45%, respectively, compared to control. Biomass partitioning shifted under drought, with increased allocation to shoots (55%) and roots (9%) and reduced allocation to reproductive organs (36%), compared to control conditions. Flowers produced under drought had 21% fewer ovules under both CO₂ environments, while pollen production remained unaffected. Seed cotton and lint weights were reduced by 19% and 15% under drought, respectively. However, plants grown under eCO₂ attained seed cotton and lint weights that were 20% higher than those grown under aCO₂, under both control and drought conditions. Drought significantly affected fiber quality, increasing micronaire by 26% and reducing fiber length by 4%, regardless of CO₂ level. eCO₂-driven alleviation primarily acts through carbon assimilation and yield compensation, with limited capacity to regulate developmental programming and quality formation. Full article

Biochar and poultry litter have been proposed as soil amendments to improve soil health in coarse-textured agricultural soils, yet their field performance under southeastern U.S. conditions remains inconclusive. This two-year field study evaluated five biochar application rates (0–44.8 Mg ha⁻¹) combined with inorganic fertilizer or poultry litter on selected soil health indicators in a sandy loam Ultisol under sweet corn production in the Georgia Coastal Plain. Treatments were arranged in a randomized complete block design with four replications and analyzed using linear mixed-effects models. Biochar application did not significantly affect aggregate stability, pH, cation exchange capacity, soluble salts, organic matter, active carbon, or estimated nitrogen mineralization, with only a marginal three-way interaction observed for microbial respiration. Poultry litter significantly increased microbial respiration relative to inorganic fertilizer, whereas responses for the remaining soil health indicators were broadly similar between fertilizer sources. Year was the dominant source of variation, with extreme rainfall in 2024 reducing aggregate stability, soluble salts, microbial respiration, and nitrogen mineralization while increasing organic matter and active carbon. These findings indicate that short-term soil health responses were driven primarily by environmental conditions rather than management practices. Under the conditions of this study, either fertilizer source can be used successfully, whereas longer-term studies are needed to determine whether biochar aging enhances soil function in sandy loam Ultisols. Full article

Global warming is profoundly altering the structure and function of permafrost peatland ecosystems, but how soil microorganisms as core regulators of biogeochemical cycles respond to the process remains unclear. We investigated peatlands of the continuous, the discontinuous, and the isolated permafrost zones in the climatically sensitive high-latitude Greater Khingan Mountains using 16S rRNA gene high-throughput sequencing and soil physicochemical analysis to systematically reveal the spatial differentiation patterns, community assembly processes, and primary environmental factors of bacterial communities. The results indicated that bacterial alpha diversity was highest in the discontinuous permafrost zone, and both permafrost type and soil depth exerted significant effects on bacterial community composition. From the continuous to the isolated permafrost zones, the relative abundance of the dominant phylum Proteobacteria decreased, while phylum Chloroflexota showed a gradual increasing trend. Co-occurrence network analysis suggested that bacterial network complexity was highest in the continuous permafrost zone, and network stability decreased along the permafrost gradient. From the continuous to the isolated permafrost zone, the relative contribution of stochastic processes declined, whereas that of deterministic processes increased. Partial least squares path modeling (PLS-PM) further demonstrated that soil pH, total organic carbon (TOC), total nitrogen (TN), and soil water content (SWC) were major drivers of bacterial communities, with their effects differing among permafrost zones. Our study elucidated the synergistic evolutionary patterns of bacterial community composition, assembly mechanisms, and environmental drivers under permafrost degradation, providing key scientific evidence for predicting the feedback of high-latitude peatlands to climate warming. Full article

Mangrove ecosystems store large amounts of soil organic carbon (SOC). However, degradation processes associated with invasive species can alter vegetation structure, hydrological conditions, and carbon cycling, with uncertain consequences for SOC storage and greenhouse gas emissions. This study evaluated changes in SOC stocks to 0–50 cm depth, soil CO₂, CH₄, and N₂O fluxes, and early restoration responses four years after ecological restoration in the Térraba–Sierpe National Wetland, Costa Rica. Comparisons were conducted among a conserved mangrove, a degraded mangrove dominated by Acrostichum aureum, and three restored sites subjected to hydrological rehabilitation with contrasting reforestation intensities. The degraded site showed significantly higher SOC contents (171 ± 31 Mg C ha⁻¹; p < 0.0001) compared to the conserved site (103 ± 26 Mg C ha⁻¹). CO₂ fluxes did not differ significantly between March and October. CH₄ and N₂O fluxes remained below the detection limits in most measurements. Redundancy analysis identified a significant association between vegetation composition and the measured environmental variables (p = 0.005). Higher CO₂ emissions were associated with the dominance of A. aureum. Plant density was positively related to SOC content (R² = 0.78). MR1 site, where hydrological rehabilitation was combined with high-density reforestation, had significantly higher SOC content than the degraded site (242 ± 24.3 Mg C ha⁻¹; p < 0.001). Soil CO₂ emissions at MR1 were also significantly lower than at the degraded site (p = 0.001). This study provides a pioneering field assessment of mangrove restoration through the control of A. aureum invasion. The results suggest that restoration design may influence soil carbon storage during the early stages of recovery. Full article

Although rice straw biochar (RSB) and milk vetch (MV) facilitate rice production and soil carbon and nitrogen (N) storage, their combined effects under N-reduction remain unclear, particularly at the aggregate-scale in reddish paddy soils. A two-year field experiment with four treatments: 100% N (N₁₀₀), 20% N-reduction + RSB (N₈₀B), 20% N-reduction + MV (N₈₀M), and 20% N-reduction + RSB + MV (N₈₀BM), was conducted in reddish paddy soil. Rice yield, soil organic carbon (SOC) and total N (TN) stocks, water-stable aggregate distribution and stability, and aggregate-associated C and N allocation were measured. Over the two-year study, N₈₀BM significantly increased grain yield by 11.2%, SOCs by 5.42%, and TNs by 6.92% compared with N₁₀₀ (p < 0.05). RSB and MV combined with N-reduction increased macroaggregate proportion by 7.92–11.8% and aggregate stability by 7.14–58.1%, while decreasing silt–clay fraction by 39.6–62.9%. Soil C and N enrichment occurred predominantly in macroaggregates. Pearson correlation and random forest analyses jointly identified aggregate distribution and stability as primary predictors of rice yield, SOCs, and TNs. Therefore, RSB + MV combined with 20% N-reduction sustained rice yield while enhancing soil aggregation and C, N sequestration, providing a rational strategy for N management in sustainable rice production. Full article

Long-term intensive agriculture has contributed to soil compaction, carbon depletion, nutrient imbalances, and disruption of microbial ecological processes, collectively constraining multiple soil functions relevant to agricultural sustainability. Crop straw return is widely considered a potential strategy for alleviating these constraints. However, existing studies and reviews have often evaluated direct straw return, straw-derived biochar, and straw-based compost separately or through individual soil indicators, limiting understanding of how biomass transformation, amendment properties, and site conditions jointly shape soil responses. To address this gap, this review comparatively synthesizes the reported mechanisms, outcomes, limitations, and potential application contexts of these three strategies within a soil multifunctionality framework. The reviewed literature is characterized by substantial heterogeneity in soil type, climate, feedstock, amendment preparation, application rate, experimental duration, and management conditions; therefore, the direction, magnitude, and persistence of reported effects require context-specific interpretation. Direct straw return was often associated with changes in soil structure, labile-carbon availability, water retention, and microbial activity, although these responses varied with straw type, incorporation depth, moisture conditions, decomposition rate, and nitrogen availability. Biochar was frequently linked to carbon stabilization, sorption, nutrient retention, and pH buffering, but the magnitude of these effects varied with feedstock properties, pyrolysis conditions, application rate, soil characteristics, and climatic context. Compost was commonly associated with increases in nutrient availability and microbial activity, whereas its performance varied with maturity, raw-material composition, salinity and pathogen risks, and field management. These comparisons suggest that the three strategies should not be assumed to be functionally equivalent, although their effects may overlap and potential combinations may be beneficial under some conditions. Based on patterns identified across the reviewed literature, we synthesize an interpretive framework linking dominant soil constraints with amendment properties and targeted soil functions. This literature-derived framework is intended to organize context-dependent evidence and support adaptive straw-return management rather than provide a universal prescription. Future research should prioritize standardized soil multifunctionality indicators, long-term multi-site comparisons, and integrated assessments of agronomic benefits, carbon persistence, nutrient losses, greenhouse gas emissions, and economic feasibility. Full article

The priming effect (PE) plays a critical role in regulating soil organic carbon (SOC) sequestration. Whether microbial inoculant combined with organic materials (e.g., crop straw) can reduce PE and enhance the fertility of coarse-textured sandy soils by accelerating straw decomposition remains poorly understood. We conducted a 90-day incubation experiment, applying ¹³C-labeled maize straw and/or microbial inoculant to coarse-textured sandy and fine-textured clay loam soils. Our results showed that microbial inoculant accelerated straw mineralization in both soils. Notably, microbial inoculant suppressed PE by 8.98% and 43.98% in the clay loam and sandy soil compared to straw addition alone, driven by adjusted soil available, C:N:P stoichiometry, and a shift in microbial community, as evidenced by a decrease in the ¹³C-G⁺ to ¹³C-G⁻ ratio from 2.68 to 2.60 in clay loam soil and from 3.2 to 1.9 in sandy soil. Microbial inoculant further increased net SOC gain (clay loam soil: +22.1%, sandy soil: +641%), with sandy soils exhibiting superior responsiveness due to reduced organo-mineral associations and enhanced microbial carbon use efficiency. In conclusion, our study provides evidence for the mechanism by which microbial inoculants suppress the PE, particularly in sandy soils. This finding establishes a theoretical basis for further exploring microbial regulation strategies in soil carbon cycling under conditions of low organo-mineral associations. Full article

Understanding the mechanisms that sustain plant diversity in arid regions is a current focus of ecological research. This study focused on the Gurbantunggut Desert, China’s largest fixed and semi-fixed desert, and systematically investigated the plant community diversity and its environmental drivers on fixed, semi-fixed, and mobile dunes. Data analysis was conducted using non-metric multidimensional scaling (NMDS) ordination, redundancy analysis (RDA), boosted regression tree (BRT), and structural equation modeling (SEM). The results indicated that taxonomic diversity (TD), functional diversity (FD), and phylogenetic diversity (PD) all exhibited consistent gradient patterns: fixed dunes > semi-fixed dunes > mobile dunes. The Net Relatedness Index (NRI) and the Nearest Taxon Index (NTI) primarily exhibited phylogenetic clustering, and habitat filtering was the dominant process in community assembly. Soil water content (SWC) and soil organic carbon (SOC) are the key drivers regulating plant diversity in this region. SWC and SOC directly and significantly influence FD and PD; however, their indirect effects on TD are weak, suggesting that species composition is also jointly constrained by abiotic processes such as dispersal limitation and interspecific competition. This study offers a theoretical foundation for differentiated ecological management of fixed, semi-fixed, and mobile dunes in the Gurbantunggut Desert. Full article

The size and stability of the soil carbon pool depend on the balance between plant litter input and soil organic carbon mineralization. As an important source of soil organic carbon, litter input plays a key role in the decomposition of soil organic carbon through the priming effect and ultimately affects soil carbon balance. Litter quality is a key factor affecting the decomposition and transformation of soil organic carbon. However, uncertainties remain regarding the effects of different-quality litters on soil mineralization and priming. In this study, we used an indoor incubation method to label China fir leaf litter and Acacia leaf litter with the isotope ¹³C. The effects of different-quality litters on the intensity and direction of soil priming effects were studied by adding different-quality litters to soils in different subtropical regions. The results show that, compared with China fir (Cunninghamia lanceolata) litter (low-quality, high C/N), Acacia (Acacia confusa) litter input (high-quality, low C/N) promotes soil mineralization and decomposition. By contrast, low-quality litter produces higher quantities of litter source C, which returns to the atmosphere through CO₂. Different-quality litters could regulate the direction and intensity of the soil priming effect. The priming effect of the Acacia litter addition treatment was higher than that of the China fir litter addition treatment. The addition of high-quality litter promotes the generation of a positive soil priming effect. The addition of Acacia litter to different regions of soil had a positive priming effect, while the addition of China fir litter had a negative priming effect for a period of time. Furthermore, the correlation analysis results showed a significant connection between soil physical and chemical indicators and litter C/N and soil mineralization and priming effects. The random forest analysis showed that litter C/N (p < 0.01) is one of the main factors affecting the soil priming effect, indicating that litter quality has a higher relative importance to the priming effect. These findings underscore the critical role of litter quality in regulating subtropical soil carbon dynamics and providing pivotal datasets for predicting terrestrial carbon sink potential. Full article

The development of sustainable and climate-resilient food systems increasingly relies on robust analytical methodologies capable of integrating environmental, biochemical, and management-related signals. In this study, a multi-isotope framework based on δ²H, δ¹⁸O, δ¹³C, and δ¹⁵N was applied to assess its capacity to discriminate between contrasting raspberry production systems and to provide chemically grounded indicators of agroecosystem functioning. Raspberry fruits (Rubus idaeus L.; cultivars Opal and Delniwa) were collected during the 2024–2025 growing seasons from two distinct systems in Romania: an organic open-field system and a rainfed agroforestry system. Stable isotope ratio analysis revealed system-dependent isotopic patterns, with the strongest differentiation observed for δ¹⁵N. Nitrogen isotope composition (δ¹⁵N) provided the strongest discrimination, with enriched values in organic fruits (2.73–9.77‰) and depleted values in agroforestry fruits (−3.01 to 0.62‰), reflecting differences in nitrogen sources and cycling pathways. Hydrogen and oxygen isotopes (δ²H: −60.46 to −4.62‰; δ¹⁸O: −6.19 to 10.41‰) were consistent with hydroclimatic variability and evaporative fractionation processes associated with soil–plant–atmosphere interactions. Carbon isotopes (δ¹³C: −28.14 to −22.62‰) provided complementary insights into plant water-use conditions. Multivariate statistical analysis supported the separation between production systems, while short-term fertilisation effects were secondary to system-level controls. The results suggest that raspberry fruits preserve an integrated isotopic fingerprint of production environment and management practices. From an analytical chemistry perspective, this work highlights the relevance of multi-isotope approaches as transferable tools for food authentication, traceability, and sustainability assessment, contributing to the broader application of stable isotope techniques across complex biological systems. Full article

Sandy desert ecosystems of Central Asia are highly vulnerable to climate change, land degradation, and increasing anthropogenic pressure, yet the soil conditions supporting native desert vegetation remain insufficiently characterized. This study investigates soil development and physicochemical properties under the canopy of Calligonum aphyllum across different geomorphological conditions in the southern Balkhash region of Kazakhstan. Field investigations were conducted within the Ili River delta, where nine soil profiles were described across three geomorphological settings. Soil samples were analyzed using standard soil analytical methods to assess particle-size composition, soil organic matter, nutrient availability, carbonate content, salinity, and sodicity indicators. The studied soils were predominantly sandy, with sand fractions ranging from 88 to 96% and very low clay content, resulting in weak horizon differentiation, high permeability, and limited water-retention capacity. Soil organic matter and total nitrogen contents were consistently low across all sites. Available phosphorus decreased with depth, particularly in carbonate-enriched horizons, whereas exchangeable potassium remained comparatively high. Total salinity was low, with chloride–sulfate and calcium–sodium dominance, and no evidence of sodicity was observed based on SAR values. Clear differences among geomorphological settings were identified, including relatively homogeneous sandy substrates, dust-enriched semi-stabilized sands, and actively reworked aeolian ridges. The results indicate that C. aphyllum can persist under nutrient-poor, coarse-textured sandy conditions and is associated with surface root concentration, local substrate stabilization, and early soil-profile differentiation. These findings highlight the ecological importance of C. aphyllum in sandy desert habitats and provide site-specific soil information relevant to vegetation-based restoration and sustainable land management in arid regions of Central Asia. Full article

Agricultural soil contamination by potentially toxic elements is a global concern due to its impacts on food safety and human health, yet comprehensive assessments remain limited in many regions of Ethiopia. This study provides an integrated assessment of PTE contamination in agricultural soils of the North Gondar Zone, Ethiopia, by evaluating physicochemical properties, pollution levels, and human health risks. Soil parameters, including pH, electrical conductivity, organic carbon, organic matter, moisture content, total nitrogen, and available phosphorus, varied among sampling sites. Soil pH ranged from moderately acidic to near-neutral, indicating variations in soil acidity likely associated with differences in moisture content, organic matter, and land management practices, while electrical conductivity values indicated non-saline conditions suitable for agriculture. Concentrations of PTEs (As, Zn, Cd, Pb, and Hg) were generally within permissible limits established by WHO and FAO. Pollution indices revealed predominantly natural background levels for As, Zn, Cd, and Pb, whereas Hg exhibited moderate to strong contamination, with the Geoaccumulation Index and Contamination Factor identifying Hg as the primary environmental risk element. Non-carcinogenic risk assessment showed that hazard quotients and hazard indices for both adults and children were below 1, indicating negligible health risks. Carcinogenic risk assessment demonstrated that all calculated risks were within the acceptable range (10⁻⁶–10⁻⁴), although children showed higher total cancer risk (TCR) values than adults due to greater exposure intensity and lower body weight. Arsenic was identified as the dominant contributor to carcinogenic risk across all sampling sites. The findings demonstrate that agricultural soils in the study area are generally safe with respect to the investigated PTEs; however, Hg contamination indices indicate a potential environmental concern requiring continued monitoring. Sustainable soil management practices, including effective pH management and liming of strongly acidic soils (pH < 5.5), are recommended to improve soil quality, reduce PTE mobility and bioavailability, and minimize future accumulation of hazardous elements while maintaining agricultural productivity. Full article

Rapid accumulation of soil lanthanum (La), cerium (Ce), and fluorine (F) caused by bastnasite mining development has increasingly become a concern worldwide in the past decades. However, the effects of the different chemical forms of these elements on the composition and diversity of soil dominant, moderate, and rare microorganisms are unclear. In this study, Planctomycetota was changed from dominant to moderate, caused by exchangeable and carbonate-bound forms of La and Ce. Both organic bound La (La_ORG) and water-soluble F (F_WS) were the crucial factors driving variations in the relative abundance of Patescibacteria and Bacteroidota from moderate to dominant, while the fungal phylum Chytridiomycota was changed from moderate to dominant, promoted by F_WS. La_ORG, the ferrum-manganese bound form of Ce, and F_WS displayed a negative correlation with the three rare bacterial phyla, i.e., Abditibacteriota, GAL15, and Deinococcota respectively. F_WS caused the disappearance of the rare fungal phylum Monoblepharomycota and the appearance of the rare bacterial phylum Fibrobacterota. Organic bound forms of both Ce and F showed a negative correlation with the bacterial Sobs and fungal Phylogenetic diversity indices, respectively. To summarize, the different chemical forms of La, Ce, and F showed varied effects on the composition and diversity of soil microbial communities. Full article