Search Results (62,695)

European peatlands have been extensively drained for agriculture, resulting in substantial carbon losses and widespread soil degradation. Peatland restoration is therefore a global priority, with rewetting recognised as a key strategy for mitigating greenhouse gas emissions and climate change. This review synthesizes current knowledge on soil transformations following the rewetting of agriculturally drained peatlands in Europe. We describe major degradation processes induced by drainage, including land subsidence, organic matter oxidation, and microbial community shifts from anaerobic to aerobic conditions. We then examine key rewetting approaches—ditch blocking, controlled flooding, and paludiculture—and their intended restoration outcomes. Rewetting fundamentally alters soil physical, chemical, and biological properties by raising and stabilizing water tables, restoring anoxic conditions, and modifying nutrient cycling and microbial processes. Findings indicate long-term stabilization of organic carbon in peat soils under anaerobic conditions, but also reveal trade-offs between reduced CO₂ emissions and increased CH₄ and N₂O fluxes. Vegetation–soil interactions strongly influence recovery trajectories, and paludiculture offers potential to align agricultural land use with climate mitigation objectives. Finally, we evaluate current research methodologies and identify major knowledge gaps, including limited long-term data and insufficient integration of hydrological, chemical, and biological processes. We highlight priorities for future research to support evidence-based rewetting strategies that deliver climate benefits while maintaining ecological and economic sustainability in European peatlands. Full article

The sugar beet (Beta vulgaris L.) industry in China occupies a pivotal position in the national sugar supply, yet drought in its major cultivation areas has become a key limiting factor for its high-quality development. Glycosyltransferases (GTs) play a pivotal role in plant responses to abiotic stress, particularly in the regulation of drought resistance. However, the systematic identification of the BvUGT90 gene family in sugar beet and the functional characterization of its members under drought stress remain largely unexplored. In this study, drought stress was simulated in the sugar beet cultivar ‘HI0466’ using the weighing method to regulate soil moisture. Samples were collected at different stress durations and after rewatering for subsequent experimental analyses. In this study, 121 members of the BvUGT90 family were identified in sugar beet, and a comprehensive analysis was conducted on their gene structures, phylogenetic relationships, promoter cis-acting elements and expression patterns under drought stress. The results showed that these 121 members were unevenly distributed across 9 chromosomes. The proteins they encode had an average amino acid length of 474, with molecular weights ranging from 10.78 to 99.10 kDa and theoretical isoelectric points (pI) from 4.68 to 8.69 (with an average of 5.76). Notably, 110 of these members (accounting for 90.91%) were identified as hydrophilic proteins. Synteny analysis indicated a high degree of homology between the BvUGT90 family members in sugar beet and their orthologous genes in Arabidopsis thaliana. Analysis of promoter cis-acting elements revealed the presence of six major categories of core elements in the promoter regions of BvUGT90 genes, including hormone-responsive elements, stress-responsive elements and pathway regulatory elements. Transcriptomic data showed that 45 BvUGT90 family members exhibited significant responsiveness to drought stress. Proteomic analysis demonstrated that 10 of these members were significantly upregulated at the protein level under drought stress, and these results were further validated by quantitative real-time polymerase chain reaction (qRT-PCR). Integrated transcriptomic and proteomic analyses identified Bv_005070_jjst.t1 and Bv6_140060_stjc.t1 as the family members with the most prominent responses to drought stress. Furthermore, transgenic transformation of sugar beet was performed, which confirmed that Bv_005070_jjst.t1 plays an important role in drought stress resistance. The findings of this study provide direct candidate genes from this family for drought-tolerant sugar beet breeding. Full article

Tillage–residue management is a controllable lever for improving maize yield and system resilience under climate variability. Here we propose a mixed-effects spatiotemporal learning framework (ME-LSTM) that integrates multi-source observations to enable robust yield prediction and management system evaluation across heterogeneous sites and years. First, we construct multi-year sliding-window inputs to represent legacy effects and cumulative influences of past management and environment. Second, a deep temporal encoder learns nonlinear dependencies from climate–soil–remote-sensing sequences to enhance interannual extrapolation. Third, a mixed-effects module explicitly separates management fixed effects from hierarchical random effects (e.g., source/study, site, year, and plot), absorbing source-specific biases and unobserved heterogeneity while improving interpretability. Finally, we parameterize management × climate/soil interactions to quantify system-specific sensitivities to environmental drivers and to support scenario-based comparison and recommendation of management options. Across multi-ecological maize datasets, ME-LSTM achieved an R² of 0.8989 with an RMSE of 309.83 kg ha⁻¹ on the test set. Ablation analyses show that removing remote-sensing features or ground-based temporal information substantially degrades performance, confirming the complementary value of multi-source fusion. Benchmarking against strong temporal baselines (LSTM, GRU, BiGRU, and Transformer) further demonstrates consistent accuracy gains of ME-LSTM, highlighting its suitability for small-sample, noisy, and hierarchically structured agricultural data. Overall, ME-LSTM provides an interpretable and scalable tool for climate-adaptive optimization of tillage–residue management and supports robust, actionable decision-making across diverse agro-ecological conditions. Full article

Against the backdrop of global warming, changes in the frequency and intensity of freeze–thaw cycles in cold regions profoundly impact soil physical structure. This review examines the mechanisms by which freeze–thaw cycles influence soil aggregate stability and pore structure evolution, focusing on revealing their synergistic evolution patterns. Results indicate that ice crystal growth during freeze–thaw processes directly disrupts soil cementation systems through expansion pressure and wedging effects, leading to aggregate disintegration and pore restructuring. This process is not unidirectional but forms a coupled feedback cycle of “ice crystal action–aggregate disintegration–pore restructuring.” Aggregate stability governs the initial pore restructuring, while the pore structure, in turn, influences aggregate stability by regulating water migration and colloidal dynamics. Responses of soil aggregates and pore structures to freeze–thaw cycles are comprehensively regulated by multiple factors, including soil physicochemical properties, freeze–thaw parameters, and anthropogenic disturbances. This synergistic evolution mechanism profoundly impacts soil water and heat transport, nutrient cycling, and erosion resistance. The paper also identifies current research gaps in regional coverage, cross-scale coupling, and in situ monitoring techniques. It envisions future efforts integrating multi-scale observations with intelligent technologies to deepen understanding of freeze–thaw-driven soil structure evolution mechanisms, thereby providing theoretical support for sustainable agriculture and ecological conservation in cold regions. Full article

In reclaimed and poorly drained soils, combined salinity–waterlogging stress markedly inhibits the early vegetative growth of maize. In this study, maize seedlings at 12 days after sowing (DAS) were subjected to combined stress by immersing the entire root system in 200 mM NaCl for 7 d (stress; ST), then transferred to recovery conditions and supplied potassium at equivalent activity (5 mM K⁺; soil drench) as KH₂PO₄ (ST + K + P), K₂SO₄ (ST + K + S), and potassium silicate (ST + K + Si) at 0 and 5 days after treatment (DAT). Morphological traits, chlorophyll fluorescence, and gas-exchange parameters were measured at PreTR (immediately after stress termination), 5 DAT, and 10 DAT. Phytohormone, mineral nutrient profiles, oxidative stress markers and redox status, osmotic and metabolic parameters, and the expression patterns of key ion transport and stress-responsive genes were quantified at 0 and 10 DAT. The effects of K supplementation were evident across the growth- and photosynthesis-related indicators. Treatment groups (ST + K + Si, ST + K + S, and ST + K + P) exhibited significantly higher carbon fixation capacity than ST at 10 DAT. The Na/K ratio was also notably reduced in all K-supplemented groups, indicating that ionic homeostasis was restored with K supplementation through improvements in various stress response indicators such as phytohormones, osmotic adjustment, and antioxidant responses. The potassium- and silicon-treated group showed the greatest recovery effect, which may reflect the physiological characteristics of cereal species. Overall, these findings provide foundational data for the development of cultivation technology to expand the cultivation area of maize. Full article

Granitic soils in the Highlands support the cultivation of Arabica coffee in northern Thailand; however, their geochemical and radiological properties are inadequately defined. This study examined major oxides, trace elements, natural radionuclides, and extractable phosphorus in granitic-derived coffee soils from the Agricultural Innovation Research, Integration, Demonstration, and Training Center (AIRID) in Chiang Mai. Twenty soil samples were obtained from 10 locations at two depth intervals (0–30 cm and 30–60 cm). Major and trace elements were analyzed via X-ray fluorescence (XRF), natural radionuclides were analyzed through high-purity germanium (HPGe) gamma spectrometry, and extractable phosphorus was determined using the Bray II method. The soils demonstrate remarkably high ⁴⁰K activity concentrations (1.2–1.9 kBq kg⁻¹) and increased K₂O contents (4.9–7.8 wt%), about three to five times more than worldwide soil averages according to Reimann & de Caritat, indicating enrichment from potassium-rich granitic rocks. Major oxide compositions suggest extensive tropical weathering, characterized by elevated SiO₂ (>60 wt%) and Al₂O₃ (>14 wt%), alongside significant depletion of CaO and MgO (<1 wt%). In topsoil, Bray II–extractable phosphorus constitutes 10–25% of total phosphorus and has a robust positive connection with P₂O₅ (R² = 0.95, p < 0.001), signifying surface accumulation and restricted vertical mobility. Multivariate analysis indicates lithogenic grouping of trace elements with negligible vertical redistribution. These findings establish a geochemical and radiological baseline for highland coffee soils in northern Thailand, with implications for soil fertility assessment, soil–plant transfer research, and evaluations of natural radioactive exposure related to coffee production. Full article

Buried oil and gas pipelines, the critical arteries of global energy infrastructure, are increasingly vulnerable to severe geological hazards such as reverse faulting, yet their structural integrity is often pre-compromised by stochastic corrosion damage accumulated during service. However, quantifying the coupled impact of spatial corrosion heterogeneity and large ground deformation remains a formidable challenge due to the complex nonlinearities involved in soil–structure interactions and wall thinning. This study establishes a probabilistic assessment framework integrating random field theory, nonlinear finite element analysis, and a generative conditional diffusion model to characterize realistic 2D non-Gaussian corrosion morphologies. The numerical results reveal a significant geometric stiffening effect induced by internal pressure, where moderate operating levels effectively suppress cross-sectional distortion by counteracting the Brazier effect. Consequently, this mechanism facilitates a fundamental transition in failure modes from localized tensile rupture to ductile buckling, significantly extending the critical fault displacement threshold. Furthermore, probabilistic fragility analysis demonstrates that the spatial dispersion of pitting, rather than just average wall thinning, governs the initiation of premature failure. Mechanistic analysis indicates that high internal pressure, while providing pneumatic support, exacerbates tensile strain localization at corrosion pits, leading to a heightened probability of premature rupture under minor fault deformations, a critical hazard that traditional deterministic models significantly underestimate. These findings provide a quantitative theoretical foundation for the reliability-based design and maintenance of energy lifelines traversing active tectonic zones. Full article

Methane (CH₄) emissions are regulated by the balance between CH₄ production and oxidation, which are mediated by methanogens and methanotrophs. Little is known about the key drivers of potential methane production (PMP) under different land use types in the Dongting Lake area. This study investigated four land use types (natural wetland, poplar plantation, rice cropland, and vegetable field) in the Dongting Lake area. The effects of land use types on (a) the abundances and community compositions of soil methanogens and methanotrophs and (b) soil potential methane production were investigated. The results showed that the soil potential methane production of the rice cropland (0.26 ± 0.02 µg g⁻¹ h⁻¹) and vegetable field (0.26 ± 0.01 µg g⁻¹ h⁻¹) was higher than that of the poplar plantation (0.16 ± 0.01 µg g⁻¹ h⁻¹). The compositions of methanogenic and methanotrophic communities varied in response to different land uses. The mcrA gene abundance in the rice cropland (0.84 ± 0.05 × 10⁸ copies/g) and vegetable fields (1.23 ± 0.15 × 10⁸ copies g⁻¹) was higher than that in the natural wetland (0.09 ± 0.01 × 10⁸ copies g⁻¹) and poplar plantation (0.08 ± 0.03 × 10⁸ copies g⁻¹). The pmoA gene abundances in the rice cropland (1.65 ± 0.08 × 10⁸ copies g⁻¹) and vegetable fields (1.88 ± 0.32 × 10⁸ copies g⁻¹) were higher than those in the natural wetland (0.16 ± 0.02 × 10⁸ copies g⁻¹) and poplar plantation (0.11 ± 0.03 × 10⁸ copies g⁻¹). In addition, both pmoA and mcrA gene abundances were positively correlated with potential methane production. However, the regression line between pmoA gene abundance and potential methane production showed a shallower slope than that between mcrA gene abundance and potential methane production. These results suggest that soil potential methane production was primarily driven by increased methanogenesis rather than reduced methane oxidation. In addition, soil organic carbon, total nitrogen, water content, and pH were key abiotic factors regulating potential methane production and the abundance and community compositions of methanogens and methanotrophs in the Dongting Lake area. Full article

Bioretention systems are increasingly implemented as green infrastructure for urban stormwater management. However, their long-term performance is jeopardized by the continuous accumulation of potentially toxic metals in substrates and vegetation, posing significant risks to ecosystem health and human safety. Despite their growing application, the mechanisms driving metal dynamics and plant responses within these systems remain poorly understood. This study conducts a comprehensive multi-factor investigation into the accumulation, mobility, and biological impacts of four representative potentially toxic metals (Cd, Cu, Zn, and Pb) in bioretention soils and vegetation. Through controlled mesocosm experiments, we quantified metal concentrations in soils and three plant species, analyzed alterations in the physical and chemical properties of soil, and assessed plant physiological stress responses. Metal concentrations were measured using inductively coupled plasma mass spectrometry (ICP-MS), and statistical analyses were conducted using one-way ANOVA (p < 0.05). Cadmium exhibited the highest enrichment, with plant uptake increasing by 330.0% to 563.2%, especially in Iris tectorum Maxim., which demonstrated superior phytoaccumulation potential. Conversely, Ophiopogon japonicus Ker Gawl. showed remarkable tolerance to metal-induced stress, maintaining stable levels of chlorophyll content, photosynthetic rate, peroxidase activity, and soluble sugar concentration. Notably, the incorporation of humic substances significantly enhanced metal immobilization in soil, while simultaneously reducing plant uptake and physiological stress, revealing a promising strategy for toxicity mitigation. By integrating the effects of plant species, substrate composition, and influent concentration, this study provides novel insights into the complex interactions governing pollutant fate in bioretention systems. The findings offer critical guidance for optimizing bioretention design and management to ensure sustained pollutant removal efficiency and ecological resilience in urban stormwater treatment. Full article

Gravitational fingering often occurs for water flow in the vadose zone and accurate modeling of this important flow process remains a significant scientific challenge. This paper presents the latest theoretical developments of the optimality-based active region model (ARM), a macroscopic framework developed for describing gravitational fingering flow in the vadose zone. ARM divides the soil into active (fingering) and inactive regions, introducing a relationship between water flux and hydraulic gradient derived from the principle of optimality that the system self-organizes to maximize water flow conductivity. Unlike traditional models, ARM’s hydraulic conductivity depends on both capillary pressure or water saturation and water flux, reflecting the unstable nature of fingering flow. The paper provides an updated mathematical derivation of ARM relationships using calculus of variations and extends ARM to account for small water flux in the non-fingering zone, resulting in a dual-flow field model. These new developments should make ARM more rigorous and realistic for field-scale applications. Full article

Paeonia delavayi displays exceptionally diverse flower colors. This study established a quantitative classification system for these colors and analyzed the relationships among pigment composition, content, and geographical distribution, providing a scientific basis for genetic diversity conservation and ornamental peony breeding. Petals from 465 plants across 30 wild populations and nurseries in central and northwestern Yunnan, China, were analyzed. Color values were quantified using CIE-Lab and Munsell color systems, while pigment content was determined using HPLC and spectrophotometry. Correlations between color values, pigments, and environmental factors were examined. The results were as follows: (1) Flower colors were classified into nine color series, each with distinct boundaries in the color value space: white (W), yellow (Y), yellow-green (YG), orange (O), orange-brown (OB), pink (P), red (R), purple-red (PR), and dark purple (DP). (2) Color values showed wide variation (a*: −23.10–65.54; b*: −4.11–94.26), indicating high diversity. (3) Yellow-category petals had high b* values (24.91–94.26), correlated with carotenoid, chlorophyll, and flavonoid content, and lacked anthocyanins. The lightness value (L*) of red-category petals was correlated with total flavonoid (TF) and total anthocyanin (ACN) content. (4) Correlation analysis showed that the formation of dark-flower colors (DP, PR, R) was significantly and positively correlated with high altitude, high soil organic carbon (SOC), and high soil total nitrogen (STN) content. The distribution of yellow-series flower colors (Y, YG) was correlated with lower altitude and weaker UV radiation, while increasing mean annual temperature (MAT) limited their distribution. (5) Analysis incorporating environmental factors showed that high-altitude areas in northwestern Yunnan, such as Shangri-La and Lijiang, had the richest flower color diversity, whereas central Yunnan’s low-altitude areas were dominated by yellow flower colors. This study indicates that the high-altitude areas of northwestern Yunnan represent the region with the richest flower color diversity in P. delavayi, and are important for the conservation of its flower color genetic diversity and as a source of genetic diversity in flower color in ornamental cultivar breeding. Full article

Abiotic stresses including drought, salinity, heat, cold, and heavy metal toxicity severely constrain plant productivity worldwide. Nitrogen (N), beyond its fundamental nutritional role, has emerged as a central regulator of plant stress responses through its involvement in metabolic reprogramming, osmotic adjustment, antioxidant defense, and hormonal signaling. This review synthesizes current advances in understanding how nitrogen availability and form influence plant tolerance to major abiotic stresses. Particular emphasis is placed on nitrogen-mediated modulation of reactive oxygen species (ROS) scavenging systems, nitrogen–carbon metabolic coordination, phytohormonal crosstalk, osmoprotectant biosynthesis, and regulation of stress-responsive gene expression. Recent molecular insights highlight the role of nitrogen transporters, nitrate signaling pathways, and nitrogen-use efficiency in stress adaptation mechanisms. Furthermore, agronomic and biotechnological strategies aimed at optimizing nitrogen management to enhance stress resilience are discussed, including precision fertilization, integrated nutrient management, and genetic approaches targeting nitrogen-responsive regulatory networks. By integrating physiological, biochemical, and molecular perspectives, this review provides a comprehensive framework for understanding nitrogen-driven mitigation strategies under abiotic stress conditions and outlines future research directions for sustainable crop production in changing environments. Full article

Geopolymer coatings exhibit outstanding corrosion resistance, high-temperature performance and thermal insulation. This thus holds broad application prospects in anti-corrosion of metals, protection of building structures, and functional coatings. However, the large-scale application of geopolymers is constrained by the availability of precursor materials. In South China, construction waste soil is predominantly composed of weathered residual soil of granite (WRSG), which is rich in silicate and aluminosilicate minerals. This soil can serve as a precursor for geopolymer synthesis upon activation. In this study, geopolymers were prepared using activated WRSG as the precursor material. The mix proportion of the geopolymers was optimized through single-factor experiments. Additionally, the hydration process and products of the geopolymer were characterized. The experimental results show that both high alkali content and low water-to-soil ratio contribute to achieving high compressive strength. The geopolymer has early strength characteristics. Its one-day compressive strength can reach 48% of 28-day value. The hydration products of the geopolymer mainly consist of amorphous sodium–aluminum–silicate–hydrate gel and primary minerals such as quartz and albite. With the increasing age, the content of chemically combined water and gel clusters grows, which densifies the microstructure and elevates the degree of hydration reaction of geopolymers. Full article

This study aims to systematically synthesize and critically evaluate the characteristics of electric arc furnace slag (EAFS) and ladle furnace slag (LFS) when applied as an alternative paving material. A systematic literature review was conducted following the PRISMA methodology, with research published between 2000 and 2024. Three major databases were searched, considering only Q1–Q2 and English articles. After independent, blinded screening by two reviewers, a total of 177 papers met the selection criteria. The results were qualitatively synthesized through bibliometric analysis, slag characteristics, and application type. Results show that asphalt concrete (AC) is the most common application of EAFS, representing 61% of studies, with many studies exploring 100% substitution of natural aggregates. Overall, EAFS and LFS demonstrate favorable mechanical properties, including high toughness, hardness, and adequate soundness, largely attributed to their iron-rich composition, supporting their use in base layers, AC, and Portland cement concrete (PCC). However, significant chemical and mineralogical variability influences swelling potential and reactivity, highlighting the need for case-specific characterization. While swelling concerns limit its use as an unbound base material, these issues are reduced when EAFS and LFS are used as a soil binder or encapsulated within AC or PCC matrices. Environmental assessments show that most EAFS and LFS samples meet the regulatory thresholds for their respective local leaching limits, though behavior varies with steel type (low-alloy vs. stainless), particle size and pH. Significant gaps remain in long-term performance and testing standards. This review proposes guidelines for selecting appropriate tests according to the intended pavement application, aiming to facilitate the safe and effective use of EAFS and LFS in road infrastructure. Full article

To address the complex dynamic mechanisms and lack of static operation data in trench-digging for transverse planting of Salix psammophila sand barriers, a transverse trench-digging device was designed. Based on the discrete element method, the Hertz–Mindlin with JKR Cohesion model was used to simulate sandy soil. The Box–Behnken experiment was adopted to optimize the single auger structure with helix angle and soil-cutting angle as factors and trench depth and working torque as indices, yielding the optimal parameters of 30° soil-cutting angle and 20.37° helix angle (5.52 cm trench depth, 2.6 N·m maximum torque). The optimized auger was integrated into the device, and a further Box–Behnken experiment was conducted under a 20 cm fixed descending depth of the lifting platform. With auger rotation speed, shaft spacing and lifting speed as factors, and trench depth, soil compaction and Salix psammophila insertion depth as indices, the optimal operating parameters were determined as 257.25 r/min, 7 cm and 9 cm/s, corresponding to 6.7 cm trench depth, 33.37 kPa soil compaction and 14.87 cm insertion depth. This study clarifies the effects of auger and operation parameters on trench-digging quality, provides a basis for the design and parameter matching of dynamic continuous operation equipment, and offers a reference for the R&D of mechanized transverse planting equipment for Salix psammophila sand barriers, which is of practical value for reducing sand control costs and improving efficiency. Full article