Search Results (19,166)

This study develops and validates a two-stage comparative framework for predicting Photovoltaic (PV) cleaning schedules by integrating high-resolution operational data with regression-based simulated datasets generated from statistical models trained on real measurements. The work directly addresses the growing need to assess whether model-based regression-based simulated data can reliably substitute real measurements in predictive PV maintenance. These models are employed to generate clean-condition power baselines and to estimate daily energy losses attributable to soiling under two distinct paradigms: (i) using real historical PV performance and environmental measurements, and (ii) using regression-derived, regression-based simulated data representing idealized clean operating conditions. Model performance is rigorously quantified using correlation coefficients (R), coefficients of determination (R²), mean absolute deviations, and binary classification metrics including accuracy, precision, recall, and F1-score. The comprehensive results demonstrate that regression-based simulated datasets exhibit high fidelity with real measurements across key electrical variables. This is evident for datasets generated using PLSR, Ridge Regression, and Robust Regression. Strong correlations are observed for DC power (R² = 0.9545) and DC current (R² = 0.9520), with mean deviations consistently below 2.2%. When a threshold-based binary decision rule (“clean” versus “do not clean”) is applied, cleaning decisions derived from simulated and real datasets show near-perfect concordance, achieving a mean F1-score of 0.9792. These results indicate that for a fixed performance-loss threshold, models using regression-based simulated data reproduce real-data-based cleaning triggers with an accuracy exceeding 97%. Furthermore, the findings confirm that regression-based simulation frameworks constitute a reliable and scalable foundation for data-driven PV maintenance optimization. By enabling efficient cleaning scheduling, these frameworks can significantly reduce operational expenditure and maximize energy yield, particularly in regions where continuous, high-quality PV monitoring data are limited or difficult to obtain. Full article

Pea (Pisum sativum L.) is an important source of food and feed and contributes to soil improvement through its association with nitrogen-fixing bacteria. By enabling higher yields and selection of tolerant genotypes, controlled environment agriculture (CEA) could meet increasing nutritional needs despite adverse conditions. The main objective of this study was to investigate the effects of drought stress on the development of vegetable pea genotypes under controlled vertical farming conditions. Plants were grown in CEA and exposed to drought stress at different developmental stages, after flowering and after pod formation. Drought significantly reduced pod and seed numbers, showing a stronger effect than genotype. For example, genotype Favorit produced 7.67 and 9.00 seeds per plant under control conditions, compared with only 2.00 and 2.67 seeds per plant under drought treatments. Pod length, seed number, and seed weight were also lower under stress, highlighting the importance of water availability during seed setting and filling. Fresh and dry biomass were mainly influenced by genotype, indicating differences in stress adaptability. The results also demonstrate that CEA can be used for reproducible abiotic stress experiments relevant to plant breeding and crop production. Full article

Optimizing planting density is a critical, cost-effective strategy for sustainable agricultural intensification, yet moving beyond static recommendations to environment-specific precision management remains a key challenge. This study establishes a three-step framework (comprising zoning, response extraction, and machine learning modeling) to determine optimum planting density (OPD) for rice (Oryza sativa L.). Utilizing a data-driven synthesis of 960 field observations from the Northeast Black Soil Region (NBSR) of China, we identified distinct spatial variability in OPD (16.6 to 37.4 × 10⁴ hills ha⁻¹). Northern regions computationally prioritized higher densities, aligning with agronomic strategies to offset thermal constraints, while southern regions favored lower densities to reduce canopy competition. Soil properties, particularly Soil Organic Carbon (SOC), pH, Cation Exchange Capacity (CEC), and Total Nitrogen (TN), were identified as the dominant predictive indicators, collectively surpassing climatic factors in their predictive importance. This highlights the foundational role of soil buffering capacity in estimating crop tolerance to density management. Based on model-derived estimates, optimized density management indicated potential yield improvements of 3.8% to 9.7% (up to 872.32 kg ha⁻¹) compared to conventional practices. By replacing uniform practices with dynamic, environment-driven strategies, this work contributes to Sustainable Development Goals (SDGs) 2 (Zero Hunger), 12 (Responsible Consumption and Production), and 13 (Climate Action), offering a scalable solution for diverse rice production systems under climate change. Full article

Fertilization is a regular management approach that can enhance soil fertility and stimulate the proliferation of beneficial microorganisms. However, the prolonged influence of fertilization practices on soil quality, microbial functional characteristics, and the underlying mechanisms still remain incompletely understood. In this study, we examined the impact of various fertilization strategies on the soil quality index (SQI) and community-level physiological profiles (CLPP) during two crop seasons (maize and soybean, respectively) in a 45-year field trial. Four treatments were implemented: unfertilized control (CK), inorganic nitrogen–phosphorus–potassium fertilizer (NPK), organic fertilizer (M), and organic–inorganic fertilization (MNPK). Results showed that across both seasons, NPK application reduced soil pH and the McIntosh index, whereas organic amendments (M and MNPK) notably enhanced total and available nutrients, SQI, microbial biomass, and enzyme activities. CLPP analysis revealed that organic fertilization significantly enhanced microbial metabolic activity and functional diversity, particularly boosting the utilization of carbohydrates (20–38%) and carboxylic acids (18–36%). Random forest modelling indicated available potassium (AK) as the primary driver of carbon metabolic activity in both seasons, revealing its critical role in regulating microbial functions. Functional metabolic diversity during the maize season was most strongly influenced by microbial entropy (qMB), whereas in the soybean season, it was available nitrogen (AN). Additionally, organic fertilization led to an indirect improvement in SQI during the maize and soybean seasons by increasing microbial biomass. In conclusion, the study underscored the importance of long-term organic fertilization for improving soil quality and provided empirical evidence to maintain the sustainable practices of agriculture in Northeast China. Full article

Industrial activities have caused heavy metals, such as cadmium (Cd), chromium (Cr), lead (Pb), and copper (Cu), to seriously threaten groundwater safety through seepage pathways. This study explored the formation of biofilms using microbe-induced calcium carbonate precipitation (MICP) technology to simultaneously reduce seepage in contaminated water and immobilize heavy metals. By optimizing the cementation fluid concentration and the intermittent grouting time, the optimal operating conditions for forming a biofilm were determined to be 1.5 mol/L cementation fluid and an intermittent time of 12 h, under which the stable infiltration rate of the sandy loam soil column can be reduced by more than 80%. We found that this biofilm can effectively inhibit the convective transport of Cd, Cr, Pb, and Cu, with the cumulative convective flux reduction rates reaching 56.25%, 56.25%, 54.54%, and 55.59%, respectively. SEM and XRD analysis indicate that the physical blockage of soil pores by calcium carbonate crystals is the dominant mechanism controlling infiltration flow, while the detection of new mineral phases, such as lead carbonate (PbCO₃), cadmium carbonate (CdCO₃), and basic copper carbonate (Cu₂(OH)₂CO₃) provides direct evidence for the chemical co-precipitation immobilization of heavy metals. This study demonstrates that MICP biofilm is a green and sustainable technology for in situ remediation of heavy metal pollution through physical–chemical synergistic effects, offering a promising alternative with a lower environmental footprint compared to conventional methods. Full article

Agricultural land covers nearly half of the Slovak Republic and shows significant spatial variation in soil quality. Persistent undocumented ownership has resulted in most land being cultivated by tenants, making lease relations central to farmland governance and increasing the role of legal regulation. In this context, the aim of this research is to assess the economic adequacy of the statutory minimum rent mechanism by analyzing its alignment with market-based rents and examining whether soil quality, on which the minimum rent is based, also significantly influences market rent levels. The analysis draws on data on customary rents published annually by the relevant ministry and administrative land price data established by law. Inductive statistical analysis and regression modeling using the correlation coefficient were applied. Results suggest that the statutory minimum rent does not consistently align with prevailing market rents despite recent legislative amendments and that its formal link to soil quality does not appear to be directly proportional. Consequently, setting minimum rents solely based on soil quality may not fully reflect prevailing market conditions and could potentially raise questions regarding its compatibility with property protection standards as interpreted in the case law of the European Court of Human Rights (ECtHR). The findings invite further reflection on the current regulatory approach to farmland rent, including the possibility of better aligning legal standards with market conditions or reassessing the functional role of the statutory minimum within the existing framework. The results indicate that the Slovak farmland rental market demonstrates characteristics consistent with a relatively autonomous market mechanism. Full article

Leveraging fungal consortia to degrade heavy oil is an emerging strategy for mitigating/cleaning up environmental pollution. However, many consortia are predominantly evaluated by measuring the biodegradation efficiency of heavy oil, with insufficient attention paid to the mechanistic underpinnings and metabolic pathways. In this study, heavy oil-degrading fungal consortia were developed for potential application in soil bioremediation. Whole-genome sequencing was used to predict the metabolic pathways and interspecific interactions driving heavy oil biodegradation. Three heavy oil-degrading fungal strains, designated Aspergillus corrugatus FH2, Aspergillus terreus FL4, and Alternaria alstroemeriae FW1, were isolated from oil sludge in the Karamay Oilfield in Xinjiang, China. Four consortia were constructed through the combination of two or three strains. The consortium F13 (FH2 + FW1) achieved 72.0% removal of heavy oil in a simulated bioremediation test over 30 days, which was more efficient than other consortia and single strains (59.5–68.5%). Notably, the mean degradation rate of long-chain alkanes (C₂₄–C₂₈) by F13 reached 95.9%. After F13 treatment, the major fractions of heavy oil showed considerable degradation, 87.4% for saturates, 92.0% for aromatics, 69.5% for resins, and 27.3% for asphaltenes. Genome annotation of FH2, FL4, and FW1 revealed the presence of core genes for degradation of n-alkanes and aromatics, e.g., CYP505, frmA, fadB, hmgA, ALDH, and ACSL. These functional genes encoded cross-lineage enzymes, enabling synergistic catabolism of C₁₃–C₂₈ alkanes and aromatics. Our findings indicated that the fungal consortium of A. corrugatus FH2 and Al. alstroemeriae FW1 has remarkable bioremediation potential for heavy oil-contaminated sites. This study provides molecular evidence for the design of targeted interventions to improve soil remediation efficiency with fungal consortia. Full article

Modern agriculture faces increasing pressure to maintain productivity while reducing soil degradation, chemical inputs, and ecological footprint, making biologically based soil-improvement strategies highly relevant. This study examined whether microbial inoculation, combined with conservation tillage practices (loosening and no-tillage), can enhance soil physical quality during pea (Pisum sativum) cultivation in an agroecological market garden in Hungary. A 2 × 2 factorial field experiment was established, testing tillage (loosening vs. no-tillage) and microbial inoculation (with vs. without) in a randomized design with three replications per treatment (12 plots total). A single microbial application was performed prior to planting using a consortium of Rhizobium spp., Ensifer spp., Pseudomonas spp., and Bacillus spp. The research focused on (I) soil penetration resistance, (II) soil moisture dynamics, and (III) infiltration capacity, with most parameters measured before and after planting. Microbial inoculation significantly reduced penetration resistance under both tillage systems and influenced soil moisture behavior, indicating improved soil structure and water retention. Infiltration rate did not change significantly within the study period. Overall, the results demonstrate that microbial amendments can rapidly improve key soil physical properties, offering a practical, nature-based strategy for resilient, low-input farming systems. Full article

The Jordan Valley is a heavily modified, data-limited transboundary river basin where water availability is constrained by both climate conditions and intensive human intervention. This study applies an integrated hydrological and hydrogeochemical modeling framework using the Soil and Water Assessment Tool (SWAT) to quantify basin-scale water availability and quality and to assess climate change impacts for the period 2000–2021. Results indicate that the basin is strongly evapotranspiration-dominated, with mean annual precipitation of 298.9 mm and precipitation-derived evapotranspiration accounting for 66.3% of rainfall. When externally supplied irrigation water is included, total evapotranspiration increases markedly, highlighting the strong dependence of agriculture on imported surface water and groundwater abstractions. Only a small fraction of total water input contributes to river discharge toward the Dead Sea, indicating a very limited internal water surplus. Hydrological dynamics are largely controlled by upstream dams and transboundary diversions, while nitrate and sediment simulations demonstrate a close coupling between hydrology, land use, and water quality. Climate projections suggest further reductions in water availability during the 21st century, exacerbating existing water scarcity. Overall, the study illustrates how intensive regulation and irrigation dependency constrain water availability in the Jordan Valley and in similar heavily modified transboundary river basins. Full article

Soils play a fundamental role in plant nutrition as primary sources of potassium (K) and magnesium (Mg), whose availability depends on soil properties and environmental conditions. The composition of major cations in the soil solution is governed by interacting factors, including soil texture, acidity, mineralogical composition, and seasonal variability during the growing cycle. This study examines the availability, mobility, and seasonal dynamics of K and Mg in the soil solution of seven naturally managed soils across four distinct periods of a complete growing season beginning in spring. An integrated field and laboratory approach was applied to assess the influence of clay mineralogy on K and Mg behavior and overall soil fertility. Seasonal soil samples were analyzed for mineral composition, total elemental chemistry, exchangeable cation pools, and soil solution chemistry. Total elemental concentrations were determined by inductively coupled plasma mass spectrometry (ICP-MS), and clay mineral assemblages were identified by X-ray diffraction (XRD), focusing on 2:1 clay minerals, mixed-layer phases, and hydroxy-interlayered minerals (HIMs). The soils were dominated by 2:1 and mixed-layer assemblages, including illite/smectite (Ill/Sm), mica/illite–vermiculite (M/Vm), and chlorite/smectite (Chl/Sm), as well as transitional HIMs such as hydroxy-interlayered smectite (HIS) and hydroxy-interlayered vermiculite (HIV). Exchangeable Mg (0.28–1.30 cmolc kg⁻¹) and K (0.12–0.97 cmolc kg⁻¹) occurred in relatively high amounts, with maximum base saturation values of 13.14% (Mg) and 4.55% (K). Soil solution concentrations ranged from 1.60 to 3.00 ppm for K⁺ and 0.90–1.70 ppm for Mg²⁺, indicating substantial mobility and enrichment from the solid phase. These findings demonstrate that 2:1 clay minerals and mixed-layer phases act as key reservoirs regulating K and Mg exchangeability and release under natural acidic conditions, thereby sustaining soil fertility and nutrient availability for plant uptake. Full article

Forest soil constitutes a critical reservoir within terrestrial carbon pools. Understanding the dynamics of soil organic carbon (SOC) in coniferous forests is crucial for enhancing ecosystem carbon sequestration capacity, yet systematic quantification of SOC characteristics and their driving factors remains limited across critical bioclimatic zones. This study examined SOC features in topsoil and driving factors across eight representative coniferous forest types in Longnan—an ecologically significant transition region of northwestern China. SOC concentrations ranged from 31.76 to 80.86 g·kg⁻¹, where Abies fargesii var. faxoniana exhibited significantly higher concentrations than other conifers. Fungal necromass dominated SOC formation (29%–45% contribution) versus minimal bacterial necromass inputs (3%–5%). Redundancy analysis identified that soil total nitrogen, C/N ratio, and tree evenness showed significant correlations with SOC concentrations and their fractions. Partial least squares path modeling revealed that tree species exerted a direct positive impact on soil total nitrogen, while having an adverse effect on soil pH. Lower soil pH and higher total nitrogen were associated with higher microbial-derived carbon and SOC concentrations. In contrast, plant-derived carbon exerted no direct influence on SOC concentrations, operating exclusively through microbial-derived carbon pathways. These results indicated that coniferous tree species-induced shifts in soil total nitrogen and pH facilitate the accumulation of microbial necromass carbon, rather than plant residues, and thus promote SOC sequestration. A. fargesii var. faxoniana can be regarded as a key strategic tree species for SOC sequestration and sustainable forest management, and its cultivation should be prioritized due to improvements in total nitrogen and microbial-derived carbon. Full article

Under global climate change, frequent droughts threaten ecosystem functions, but how drought characteristics affect ecosystem resilience remains unclear. Focusing on the Dongjiang River Basin, China, we identified drought events at an 8-day scale from 2000–2024 using multi-source remote sensing and reanalysis data. The water use efficiency-based resilience index (R_de) was calculated, and a random forest model quantified the contributions of 21 potential driving factors. The model explained 68% of R_de variance (R² = 0.68, RMSE = 0.12). Downward shortwave radiation was the primary factor, followed by antecedent water use efficiency and soil moisture anomaly, with drought intensity and air temperature ranking fourth and fifth. All dominant factors exhibited nonlinear threshold effects: R_de decreased significantly after radiation exceeded ~110 W·m⁻²·(8d)⁻¹; R_de declined when standardized soil moisture anomaly fell below −2.0; and R_de increased sharply when drought intensity exceeded 12%. Drought intensity far outweighed duration and severity, establishing it as the key drought attribute. This study reveals the dominant drivers and their thresholds governing ecosystem resilience in the Dongjiang River Basin, providing quantifiable indicators for ecological drought early warning. Full article

Arsenic (As) contamination of soils is a critical environmental and geochemical concern, with its mobility and bioavailability largely controlled by molecular-scale interactions with soil minerals. This study investigates the adsorption behavior of arsenate [As(V)] and arsenious acid [As(III)] on major clay minerals to elucidate fundamental controls on As retention in soil and sediment systems. Molecular modeling approaches were employed to investigate these interactions. Density functional theory (DFT) calculations were performed on cluster models of illite, chlorite, montmorillonite, and kaolinite to evaluate adsorption configurations and binding energies of arsenate and arsenious acid. In addition, semiempirical (PM6) and classical force-field (UFF) methods were used to examine the influence of vermicompost-derived organic matter on arsenate-mineral interactions. Multiple adsorption configurations, including atop atom, bridge, three-fold filled, and three-fold hollow sites, were evaluated, and binding energies were calculated with correction for basis set superposition error. The results indicate that three-fold hollow sites are the most favorable, with As(V) binding energies of 60–65 kcal mol⁻¹ on illite, chlorite, and montmorillonite, reaching 75 kcal mol⁻¹ on kaolinite at a surface distance of 2.7 Å. In contrast, As(III) shows weaker and energetically flatter adsorption, with binding energies of 28–54 kcal mol⁻¹ and larger equilibrium distances of 3.2–4.0 Å. Modeling of vermicompost addition suggests a substantial reduction in arsenate binding on most clay minerals, except illite, indicating competitive or disruptive interactions at mineral surfaces. These findings provide quantitative, atomistic insight into mineral- and amendment-specific controls on As stabilization and mobility in soil and sediment systems. Full article

Mountain forests within arid zones function as critical regional “water towers” and biodiversity hotspots, providing essential ecosystem services (ESs) such as carbon sequestration, water retention, soil conservation, and habitat maintenance. Despite their ecological significance, the spatiotemporal characteristics of these services remain insufficiently characterized. For this study, focusing on the Altai Mountains in northwestern China, we employed the InVEST model using climate, land cover, and soil survey datasets (2000–2020) to quantify ES dynamics, then applied Spearman rank correlation to analyze their spatial interactions. Results indicated the following distinct spatiotemporal patterns: (1) Temporally, water retention capacity increased by 23.5% from 2000 to 2020, with the most rapid growth occurring between 2000 and 2010, whereas carbon storage experienced a slight decline of 1.9%. (2) Spatially, water retention followed a “high-North, low-South” distribution, while carbon storage and habitat quality were highly concentrated in the central mid-elevation zones (1400–2400 m). (3) Trade-off intensification: a significant negative correlation between water retention and carbon storage deepened over the study period, highlighting an escalating “water–carbon” conflict. The aforementioned findings suggest that future management should be focused on avoiding high-density afforestation in mid-elevation water-sensitive zones to prevent excessive evapotranspiration. Instead, spatially differentiated strategies—prioritizing water yield protection in high-altitude regions and stand structure optimization in mid-altitude forests—are essential for reconciling regional ecosystem service trade-offs. Full article

Nanoplastics (NPs) are increasingly detected in agricultural soils, yet their influence on arsenic (As) transfer and plant toxicity remains unclear. Lettuce (Lactuca sativa L.) was cultivated in farmland soil with a naturally high As background (98.8 mg·kg⁻¹) to assess how polyethylene nanoplastics (PE NPs) affect rhizosphere conditions, As accumulation, and plant performance. PE NPs partially buffered soil acidification but reduced rhizosphere water content, while total soil As remained largely unchanged. Leaf As increased by 35–39%, with reduced biomass (up to 30%) and lower chlorophyll status (SPAD ~7% lower). Metabolomic analyses indicated dose-dependent alterations in central carbon metabolism and phenylalanine-related antioxidant metabolites, including suppressed tricarboxylic acid cycle intermediates at higher PE levels. Overall, PE NPs enhanced transfer of background As to edible leaves and intensified phytotoxicity, underscoring the need to consider nanoplastics in risk assessment of As-affected soils. Full article