Search Results (2,196)

Studying the relationships between understory plant diversity and soil physicochemical properties aids in understanding the sustainable development of plantation forests. Vegetation restoration in latosol gully erosion areas plays a key role in preventing soil erosion. Variations in understory plant diversity and soil physicochemical properties in areas that have undergone vegetation restoration subsequent to gully erosion are not well understood. In this study, we investigated the understory species composition, importance values, plant diversity, and soil physicochemical properties and explored their correlations following vegetation restoration using four forest types (Acacia mangium forest, Eucalyptus robusta forest, A. mangium–E. robusta mixed forest, and A. mangium–E. robusta–Schizostachyum pseudolima mixed forest) in the Mahuangling Watershed, Hainan Province. A total of 49 plant species belonging to 47 genera and 20 families were recorded. The E. robusta forest (31 species) and A. mangium–E. robusta mixed forest (27 species) had higher species richness and more complex community structures. The dominant shrub species were Rhodomyrtus tomentosa, Breynia fruticosa, Aporosa dioica, and Dodonaea viscosa, while the dominant herbaceous species were Ageratum conyzoides, Chromolaena odorata, Spermacoce alata, and Erigeron sumatrensis. In all four vegetation restoration forest types, the richness index in the herbaceous layer was higher than in the shrub layer, while the diversity index showed no significant difference between the shrub and herbaceous layers (p > 0.05). The soil bulk density ranged from 1.57 g·cm⁻³ to 1.63 g·cm⁻³, with the A. mangium forest having better soil total porosity (38.77%) and water-holding capacity (190.37 t·hm⁻²) than the other forests. NH₄⁺-N and NO₃⁻-N were lower in the E. robusta forest, while the A. mangium forest had significantly higher organic matter content (13.71 g·kg⁻¹). Correlation and redundancy analyses showed that soil water content, pH, and soil organic matter were key factors affecting herbaceous-layer and shrub-layer plant diversity. On the whole, we suggest that the planting of pure and mixed forests of A. mangium should be considered in future ecological restoration projects in the gully erosion area of Mahuangling in order to maintain the stability of understory plant diversity and improve latosol soil fertility. Full article

Atmospheric nitrogen (N) deposition is increasing N inputs to forests, but consequences for soil carbon (C) status and respiration partitioning remain uncertain. We conducted a five-year field N-addition experiment in an alpine coniferous forest in Xizang, China. We measured post-treatment soil properties, extracellular enzyme activities, estimated microbial C use efficiency (CUE), total soil respiration (Rs), root-exclusion heterotrophic respiration (Rh), and residual autotrophic respiration (Ra = Rs − Rh). Relative to the zero-N control (N0; 0 kg N ha⁻¹ yr⁻¹), N1 and N2 had higher post-treatment soil organic C, whereas all N-addition treatments had >60% lower available phosphorus and 19.12%–64% lower Rs. The Rs contrast was more strongly reflected in estimated Ra (35.93%–87% lower), whereas Rh responses varied among treatments and campaigns. N addition altered enzyme allocation and was associated with 6.70%–16.60% lower estimated CUE. Exploratory random forest and partial least squares path models indicated that Rh covaried more closely with microbial biomass, whereas Rs and estimated Ra covaried with soil physicochemical conditions and phosphorus availability. Thus, higher post-treatment soil C in some N-addition treatments co-occurred with lower Rs. However, the absence of pretreatment soil data and direct root measurements limits causal interpretation. Full article

Though many food systems on Earth offer benefits to space travelers, their ability to meet the demands of spaceflight remains unestablished. This study examines the application of magnesium oxide-coated halloysite nanotubes (MgO-HNTs), synthesized via electrodeposition, to enhance seed germination and early plant development under Earth, lunar, and Martian soil conditions. Successful surface modification was confirmed by scanning electron microscopy. Growth experiments with Heirloom Cherry Tomato and Golden Tomato seeds were conducted under hydroponic and soil-based conditions and subsequently extended to lunar and Martian regolith simulants. A Response Surface Methodology approach, based on a Box-Behnken Design, evaluated the effects of temperature, MgO-HNT concentration, and light duration on multiple growth responses, identifying seedling length and the root length stress tolerance index (RLSI) as the most responsive indicators of treatment. Optimal conditions (25 °C, 12 h photoperiod, 100 mg/mL MgO-HNTs) produced the greatest increases in root and shoot length in Earth soil. In lunar regolith, optimal root development occurred at 100 mg/mL (root length: 17.7 mm, shoot length: 5.08 mm, RLSI: 141.1%, germination: 80%), whereas Martian regolith peaked at 10 mg/mL (root length: 12.3 mm, shoot length: 4.28 mm, RLSI: 167.9%, germination: 100%), which may be associated with differences in the physicochemical properties of the two substrates. These findings offer preliminary evidence that MgO-HNTs can enhance early plant development across terrestrial and extraterrestrial substrates. As this study was limited to a single crop species under short-term, controlled laboratory conditions without direct physiological or biochemical biomarker measurements, further validation will be required to support broader agricultural or in-situ resource utilization (ISRU) applications. Full article

In the primary spruce-fir-Korean pine forest affected by historical windthrow, soil water-holding capacity shows complex spatial associations with forest microenvironment and soil physicochemical properties. However, its spatial variability and multi-factor hierarchical association pathways remain poorly understood. Taking the primary spruce-fir-Korean pine forest on a historically windthrow-affected site in the Liangshui National Nature Reserve, Xiaoxing’an Mountains, China as the research object, geostatistics and partial least-squares structural equation modeling were used to analyze the spatial pattern of topsoil (0–20 cm) water-holding capacity and its environmental association pathways. The results showed saturated, capillary and field water-holding capacities of topsoil exhibited moderate variability and strong spatial autocorrelation (all nugget to sill ratios < 25%), showing a patchy distribution. No significant direct association was detected between windthrow mechanical disturbance intensity and topsoil water-holding capacity. Bulk density (path coefficient = −0.685, p < 0.001) and soil porosity (path coefficient = 0.273, p < 0.001) had significant direct associations with soil water-holding capacity, whereas soil particle size distribution showed no significant effect (p > 0.05). Canopy structure and understory microclimate exerted indirect associations with soil water-holding capacity via soil structure; litter showed no significant associative effect (p > 0.05). These results indicate that soil water-holding capacity on the historically windthrow-affected site was not randomly distributed, but presented an ordered patchy pattern closely related to in-plot micro-environmental factors. Full article

Nanomaterials have emerged as key platforms for environmental remediation owing to their tunable surface chemistry, high specific surface area, and multifunctional physicochemical properties. This review provides a critical comparison between conventional nanomaterials (CNMs) and phyto-mediated nanomaterials (PMNs), with particular emphasis on material design, surface chemistry, pollutant removal mechanisms, environmental performance, and sustainability. CNMs, including metal and metal oxide nanoparticles, carbon-based nanomaterials, and hybrid nanocomposites, offer excellent adsorption, photocatalytic, redox, and antimicrobial performance but remain constrained by concerns regarding toxicity, environmental persistence, and energy-intensive synthesis. PMNs provide a greener alternative by integrating plant-derived surface chemistry with nanomaterial functionality, potentially reducing reliance on hazardous synthesis reagents while modifying interfacial interactions relevant to environmental remediation. The review critically discusses the mechanistic roles of adsorption, surface complexation, photocatalytic degradation, electron-transfer processes, and reactive oxygen species (ROS) generation in pollutant removal. Recent advances in water purification, soil and groundwater remediation, carbon sequestration, and climate-related environmental applications are comprehensively summarized. Finally, current challenges associated with reproducibility, scalability, environmental safety, life-cycle assessment, and regulatory considerations are critically analyzed, together with future perspectives toward the rational design of sustainable nanomaterials for next-generation environmental remediation technologies. Full article

Soil degradation constrains cropland productivity in Northeast China, where conservation tillage has been widely adopted to improve soil structure and sustain maize (Zea mays L.) production. However, previous studies have focused mainly on single soil types or regional-scale assessments, and the applicability of conservation tillage across contrasting cultivated soil types remains inadequately characterized. From 2021 to 2023, field experiments were conducted across geo-ecological zones within mid-temperate sub-humid and mid-temperate sub-arid climatic regions, encompassing seven typical cultivated soil types: Aeolian sandy soil, Bielic, Black soil, Chernozem, Histosol, Inceptisol, and Mollisols. A strip-tillage with straw return treatment (ST) was compared against no-tillage with straw mulching treatment (CK) to systematically evaluate the effects of strip-tillage on (i) soil physical properties (bulk density and porosity), (ii) soil chemical properties (organic matter and total nutrient contents), and (iii) maize yield components. Across the full dataset, ST significantly reduced soil bulk density and increased total porosity relative to CK; however, soil-type-specific comparisons showed that significant responses were detected only in some soil types. By contrast, soil chemical properties were significantly influenced by the treatment × soil type interaction: SOM and STN contents increased significantly in Inceptisol under ST, STP increased significantly in Mollisols, and STK increased significantly in Histosol. A PCA-derived composite physicochemical score, based on six standardized soil indicators, was higher under ST than CK in six of the seven soil types relative to CK, with the most pronounced improvements occurring in Aeolian sandy soil (+1.23), Bielic (+0.87), and Black soil (+0.65); significant maize yield increases under ST were detected in Aeolian sandy soil and Black soil, with mean increases of 7.07% and 10.94%, respectively. The associations between maize yield components and grain yield differed between ST and CK, with 1000-kernel weight showing a stronger association with grain yield under ST. Collectively, these findings indicate that ST can improve soil physical structure, but its effects on soil chemical properties, maize yield, and yield-component associations are soil-type dependent. Full article

The increasing demand for sustainable agricultural practices has driven growing interest in organic fertilizers derived from waste streams as alternatives to mineral fertilizers. This study evaluated, in a pilot trial, the effectiveness of using raw digestate, composted digestate and composted sewage sludge in a crop rotation over two consecutive years of maize and Italian ryegrass. Crop yield, forage quality, and soil physicochemical properties were assessed to determine the potential of these recycled organic nitrogen sources. The results differed between the two species of forage. In maize, organic fertilizers maintained yield and forage quality comparable to chemical fertilization, while composted sewage sludge significantly increased average plant height. These findings indicate that recycled organic amendments can partially or totally replace mineral nitrogen fertilizers, contributing to nutrient recycling and waste valorization within a circular economy framework. In contrast, Italian ryegrass showed lower yield under organic fertilization than under chemical fertilization, suggesting that additional management strategies may be required to optimize nutrient availability for this crop. Furthermore, raw digestate application tended to increase soil pH, which may provide benefit subsequent crop. Overall, the results suggest that digestate and sludge-based fertilizers are promising alternatives for maize performance, although their effectiveness in Italian ryegrass requires additional strategies. Full article

Due to the multiple benefits of drip fertilization, such as water conservation, fertilizer reduction and environmental protection, it has been widely adopted in orchard cultivation in China. However, the effects of drip fertilization on soil nitrogen in citrus orchards of different ages and their mechanisms are still unclear. Therefore, this study carried out soil surveys in three citrus (Citrus reticulata Blanco) orchards of different ages under two irrigation and fertilizer treatments (NF: normal fertilization; DF: drip fertilization) in Nanfeng City, Jiangxi Province, renowned as the “Chinese Citrus Township”. Soil nitrogen and properties, bacterial communities, N-cycling functional genes and their correlations were analyzed. In the results, soil TN content reduced under DF in the orchard that was 1–2 years old but increased in the orchard that was >10 years old. Soil SN under DF was generally higher and more responsive to tree age, mainly driven by SON. Soil bacterial diversity and composition were influenced by DF, but related to tree age, soil N-cycling showed an “active retention” mode under DF. Soil nitrogen was more related to soil physicochemical properties in the irrigation stage but to soil bacterial factors in the non-irrigation stage. This study can provide a theoretical basis to promote the differentiated application of water–fertilizer integrated technology in citrus orchards of different ages. Full article

The application of exogenous nutrient bags (ENBs) is critical for achieving high yields in morel mushroom cultivation; however, the high cost and lack of locally adapted formulations have become major constraints for the sustainable expansion of this industry. This study aimed to evaluate the effects of ten treatments, including a conventional formulation control, incorporating locally available agricultural by-products (rapeseed straw, organic fertilizer, alfalfa, and oats), on soil fertility, enzyme activity, microbial community structure, and ultimately the yield and quality of cultivated Morchella sextelata in Jianzha County, Qinghai. A randomized complete block design was established, and soil physicochemical properties, microbial biomass carbon/nitrogen/phosphorus (MBC/MBN/MBP), and enzyme activities (urease, phosphatase, and catalase) were measured at 38, 62, and 137 days post-application, while bacterial and fungal community compositions were characterized via high-throughput sequencing of 16S rRNA and ITS2 genes. Our results demonstrated that the wa-60 treatment (30% wheat + 60% alfalfa) outperformed all the other formulations, delivering the highest yield (1.32 ± 0.08 kg/m²) and a 28.6% increase over the control (1.03 ± 0.06 kg/m²; p < 0.01), while maintaining a high total amino acid content (19.8 g/100 g). Soil analysis revealed that wa-60 notably enhanced urease activity (peaking at 85 µg/g/h at day 137) and alkaline phosphatase activity (322.55 µg/g/h), alongside significant increases in MBC and MBN. Microbiome profiling further demonstrated that wa-60 selectively increased the relative abundance of various taxa, particularly the bacterial phylum Bacteroidota and the fungal phylum Mortierellomycota. Correlation analyses indicated strong positive associations among these enriched taxa (primarily at the genus level), enhanced enzyme activities, and improved soil nutrient availability. Collectively, these findings establish that the wa-60 formulation, leveraging locally sourced alfalfa, represents a cost-effective and high-performance strategy for morel cultivation in the Qinghai Plateau, providing a microbial–ecological basis for optimizing ENB design and offering a practical pathway for recycling agricultural waste in edible mushroom production. Full article

Heavy metal contamination of agricultural soils and urban green spaces has become a major environmental concern, threatening ecosystem functioning, food safety, and sustainable land management. Silicon-based growing media have emerged as an environmentally friendly approach for reducing metal mobility while enhancing plant establishment in contaminated environments. Despite growing research interest, a comprehensive evaluation of the mechanisms, effectiveness, and practical applications of silicon-amended growing media across diverse plant systems remains lacking. This systematic review addresses this gap by synthesizing current evidence following the PRISMA 2020 framework. A systematic search of Web of Science, Scopus, PubMed, ResearchGate and Google Scholar identified 247 publications published between 2010 and 2025, of which 32 peer-reviewed studies met the predefined inclusion criteria for qualitative analysis. The reviewed literature demonstrates that silicon incorporation into growing media improves substrate functionality by modifying physicochemical properties, immobilizing heavy metals, regulating metal transport within plants, strengthening antioxidant and osmo-protective defense systems, preserving photosynthetic activity, and improving nutrient acquisition and water-use efficiency. Furthermore, silicon influences molecular signaling pathways and promotes beneficial rhizosphere interactions that collectively enhance plant resilience under metal stress. Among the evaluated materials, silicon nanoparticles consistently exhibited greater remediation efficiency than conventional silicon sources because of their higher surface reactivity and improved bioavailability. Overall, silicon-based substrate engineering represents a multifunctional and sustainable strategy for mitigating heavy metal contamination while improving the performance of agricultural crops and urban vegetation. Future research should focus on validating these findings under long-term field conditions, optimizing silicon formulations for different substrate types and contamination scenarios, evaluating environmental safety, and integrating silicon-based technologies into climate-resilient agricultural practices and urban green infrastructure. Full article

The rapid development of biodegradable polymers has intensified the need for reliable, standardized methodologies that can accurately assess their environmental fate. However, biodegradability is not an intrinsic property of materials, but rather the result of complex interactions between polymer chemistry, physicochemical characteristics, environmental conditions, and microbial activity. Consequently, biodegradation performance determined under one set of conditions cannot be directly extrapolated to other environments, highlighting the importance of selecting appropriate testing methodologies. This review provides a comprehensive and critical evaluation of the main international standards used to assess polymer biodegradability, including ISO, ASTM, EN, and OECD methods applicable to soil, industrial composting, freshwater, and marine environments. It discusses the fundamental mechanisms of polymer biodegradation, together with the major factors governing degradation kinetics, and comparatively analyzes the biodegradation behavior of polyesters, polysaccharides, polyamides, and polyesteramides across different environmental compartments. Unlike previous reviews, this work critically compares the applicability, strengths, limitations, and biodegradation endpoints of standardized methodologies, identifies current methodological gaps, and proposes a practical decision-making framework for selecting appropriate tests according to the intended end-of-life scenario of polymeric materials. Finally, it highlights the need for more harmonized and environmentally relevant testing approaches to better distinguish compostability from true environmental biodegradability. Full article

The growing environmental impact of petroleum-based plastic packaging has accelerated the development of biodegradable materials from renewable resources. In this study, cellulose extracted from wheat straw was regenerated into biodegradable films using calcium-ion crosslinking and glycerol plasticization. A Box–Behnken experimental design optimized cellulose content (0.35–0.5 g), calcium chloride concentration (200–800 nm), and glycerol concentration (0.5–1.5%) to produce films with balanced mechanical and barrier properties. The optimized film was characterized for its physicochemical, mechanical, optical, antioxidant, and biodegradation properties and evaluated for fresh grape packaging. The film exhibited favorable mechanical strength of 30.82 ± 4.70 MPa, controlled water vapor permeability of 0.59 ± 0.06 10⁻¹⁰ gm⁻¹ s⁻¹ Pa⁻¹, elongation at break of 4.36 ± 0.35%, moderate transparency of 22.95 ± 0.65% mm⁻¹ at 600 nm, and ultraviolet light-blocking capability, allowing only 9.57 ± 1.44% of UV-B at 300 nm, and an IC₅₀ value of 0.33, indicating moderate antioxidant potential, with 35% biodegradation after 37 days at a soil moisture of 24%. During ambient storage, grapes packaged with the film reached 15% weight loss by 13 days, while slowing changes in total soluble solids, pH, titratable acidity, total phenolic content, and vitamin C, and delaying visible quality deterioration. Compared with the uncovered control, packaged grapes maintained acceptable quality for approximately six additional days, reaching 15 days of storage. Unlike conventional polystyrene film, which promoted excessive gas accumulation and fruit cracking, the wheat straw cellulose film provided a semipermeable barrier that balanced moisture and gas exchange. The systematic optimization of these formulations, followed by comprehensive characterization of the optimized films, demonstrates the potential of wheat straw cellulose as a functional material for developing cellulose films as sustainable, biodegradable packaging materials for extending the postharvest quality of fresh produce. Full article

Synthetic materials used to enhance the productivity of agricultural crops have, in turn, begun to exert negative impacts on soil ecology. This has led to an increased interest in environmentally safe biomaterials. In this context, an antibacterial biofilm was developed based on oxidized starch and microcrystalline cellulose (MCC) as well as cellulose nanofibers (CNFs) derived from corn husk (CH). According to the obtained results, the film containing 3% CNFs exhibited the highest mechanical strength, reaching 3.87 MPa. To impart antibacterial properties to the resulting biofilm, different volumetric amounts of copper nanoparticles (CuNPs) synthesized via a green method were incorporated. As a result, the biofilm containing 1 mL of CuNPs demonstrated the highest antibacterial activity. It was also found that, compared to the pristine film, the mechanical strength of the CuNPs-immobilized biofilm decreased by threefold, while its flexibility increased. The antibacterial biofilm was comparatively characterized using FTIR, XRD, SEM, and TGA techniques, and its physicochemical properties were determined. The biodegradation behavior of the biofilm in soil was also investigated, revealing that 57% of its total mass degraded within 80 days. In this context, it was determined that the degradation of the biofilm did not significantly affect soil pH or the levels of macro- and microelements. Based on its physicochemical properties, the obtained biofilm demonstrates high potential for application in the agro-industrial sector as a mulching film, as well as in the production of food packaging materials and bioplastics. Full article

Under intensive urbanization, botanical gardens soils can serve as reference plots for urban areas, reflecting both natural (pedogenic) and anthropogenic factors of soil formation. In this context, historical and archeological information on the Botanical garden of Saint Petersburg State University (BG SPbU) is presented. For the first time, morphological, physicochemical, and ecotoxicological characteristics of the BG SPbU soils are assessed using full-profile soil pits. The ecological features of the BG SPbU are noted, and the specific structure of the upper soil layer (up to 2 m) is examined. The physicochemical properties of the BG SPbU soils are consistent with the optimal levels for green spaces of the highest (I) category. In the 0–90 cm layer of the studied soil pits, elevated concentrations (relative to Russian regulatory standards) of toxic trace elements (lead, zinc, arsenic) are found. No signs of vegetation stress were detected during the survey. At the same time, the measured concentrations of Pb, Zn, and As exceed the Russian MPC (maximum permissible concentrations) and APC (approximate permissible concentrations) for heavy metals. These exceedances provide important information for further monitoring and decision-making regarding urban pollution regulation, and contribute to the discussion on revising the MPC and APC values in line with international standards. The results can be used to optimize management practices for green spaces of the BG SPbU and can also be incorporated into the long-term urban environmental monitoring program initiated in Saint Petersburg in 1991. Full article

Mediterranean ecosystems are particularly exposed to wildfire because seasonal summer drought, high temperatures, and flammable vegetation favour fire ignition and spread. Because post-fire nutrient patterns are context dependent, this observational study compared soil organic carbon (SOC) and nitrogen (N) stocks and selected physicochemical properties among sampling campaigns conducted before and after a wildfire in Vesuvius National Park (Italy). Surface mineral soil (0–10 cm) was sampled beneath two vegetation-cover categories (shrubs and trees) before fire (2015–2017) and approximately 22, 46, and 70 months after fire. Soils were analysed for pH, water content (WC), soil organic carbon concentration (Corg), total N concentration, bulk density, Corg:N ratio, and apparent fixed-depth soil organic carbon (SOC) and N stocks. Soil properties varied primarily among sampling periods, whereas vegetation category showed a more limited association. The short-term campaign was characterised by the highest pH and the lowest WC and total N concentration, whereas total N concentration and apparent fixed-depth N stock reached the highest median values during the long-term campaign. Vegetation category was associated only with WC and Corg:N ratio, which were generally higher under trees, and no significant sampling period × vegetation interaction was detected. Corg concentration and apparent fixed-depth SOC stock did not differ significantly among sampling periods. These differences cannot be attributed exclusively to wildfire or elapsed time because contemporaneous unburnt controls were unavailable and sampling period, calendar year, and spatial variability were not fully separable. The findings nevertheless show the value of jointly monitoring element concentrations and soil physical properties when assessing Mediterranean forest soils after wildfire. Full article