Search Results (9,306)

Addressing the challenges of low resource-use efficiency and supply–demand mismatch in Hami melon production, this study investigated the interactive effects of irrigation and fertilization to identify an optimal regime that balances yield, water conservation, and resource-use efficiency (i.e., water use efficiency and fertilizer partial factor productivity). A greenhouse experiment was conducted in Hami, Xinjiang, employing a two-factor design with five irrigation levels (W1–W5: 60–100% of full irrigation) and three fertilization levels (F1–F3: 80–100% of standard rate), replicated three times. Growth parameters, yield, water use efficiency (WUE), and partial factor productivity of fertilizer (PFP) were evaluated and comprehensively analyzed using the entropy-weighted TOPSIS method, regression analysis, and the NSGA-II multi-objective genetic algorithm. Results demonstrated that irrigation volume was the dominant factor influencing growth and yield. The W4F3 treatment (90% irrigation with 100% fertilization) achieved the optimal outcome, yielding 75.74 t ha⁻¹—a 9.71% increase over the control—while simultaneously enhancing WUE and PFP. Both the entropy-weighted TOPSIS evaluation (C = 0.998) and regression analysis (optimal irrigation level at w = 0.79, ~90% of full irrigation) identified W4F3 as superior. NSGA-II optimization further validated this, generating Pareto-optimal solutions highly consistent with the experimental optimum. The model-predicted optimal regime for greenhouse Hami melon in Xinjiang is an irrigation amount of 3276 m³ ha⁻¹ and a fertilizer application rate of 814.8 kg ha⁻¹. This regime facilitates a 10% reduction in irrigation water and a 5% reduction in fertilizer input without compromising yield, alongside significantly improved resource-use efficiencies. Full article

An inorganic–organic hybrid nano-adsorbent was prepared by chemical immobilisation of an organic Schiff base Cu (II) ion receptor, DHB ((E)-N-(1-(2-hydroxy-6-methyl-4-oxo-4H-pyran-3-yl) ethylidene) benzohydrazide), a selective dehydroacetic acid-based chemosensor, onto a mesoporous silica support. In order to prepare the sorbent, the silylating agent was anchored onto the silica. During this procedure, 3-Chloropropyl trimethoxy silane (CPTS) was attached to the surface, increasing hydrophobicity. By immobilising DHB onto the CPTS platform, the silica surface was activated, and as a result the coordination chemistry of the Schiff base generated a hybrid adsorbent with the capability to rapidly sequestrate Cu (II) ions from wastewater, as an answer to combat growing Waste Electrical and Electronic Equipment (WEEE) contamination in water supplies, in the wake of a prolonged consumerism mentality and boom in cryptocurrency mining. The produced hybrid materials were characterised by FTIR, proximate and ultimate analysis, nitrogen physisorption, PXRD, SEM, and TEM. The parameters influencing the removal efficiency of the sorbent, including pH, initial metal ion concentration, contact time, and adsorbent dosage, were optimised to achieve enhanced removal efficiency. Under optimal conditions (pH 7.0, adsorbent dosage 3 mg, contact time of 70 min, and 25 °C), Cu (II) ions were quantitatively sequestered from the sample solution; 93.1% of Cu (II) was removed under these conditions. The adsorption was found to follow pseudo-second-order kinetics, and Langmuir model fitting affirmed the monolayer adsorption. Full article

Post-earthquake fires often cause more severe losses than the earthquakes themselves, highlighting the critical role of water distribution networks (WDNs) in mitigating fire risks. This study proposed an improved assessment framework for the post-earthquake firefighting functionality of WDNs. This framework integrates a WDN firefighting simulation model into a cloud model-based assessment method. By combining seismic damage and firefighting scenarios, the simulation model derives sample values of the functional indexes through Monte Carlo simulations. These indexes integrate the spatiotemporal characteristics of the firefighting flow and pressure deficiencies to assess a WDN’s capability to control fire and address fire hazards across three dimensions: average, severe, and prolonged severe deficiencies. The cloud model-based assessment method integrates the sample values of functional indexes with expert opinions, enabling qualitative and quantitative assessments under stochastic–fuzzy conditions. An illustrative study validated the efficacy of this method. The flow- and pressure-based indexes elucidated functionality degradation owing to excessive firefighting flow and the diminished supply capacity of a WDN, respectively. The spatiotemporal characteristics of severe flow and pressure deficiencies demonstrated the capability of firefighting resources to manage concurrent fires while ensuring a sustained water supply to fire sites. This method addressed the limitations of traditional quantitative and qualitative assessment approaches, resulting in more reliable outcomes. Full article

Quality control of drinking water is essential for safeguarding public health, particularly in densely populated urban environments. Environmental microbiological monitoring can complement conventional surveillance by providing deeper insights into the dissemination of pathogens and antimicrobial resistance genes within aquatic systems. In this study, we assessed the quality of wastewater and treated water from two urban water supply systems, representing the southern and northern regions of Porto Alegre, Rio Grande do Sul, Brazil, across four climatic seasons between 2024 and 2025. Fifteen water samples were analyzed, including raw water from Guaíba Lake and treated water collected from public distribution points. The Water Quality Index was calculated, microbiological indicators were quantified, and carbapenem resistance genes were detected using molecular assays. Most treated water samples complied with established bacteriological standards; however, the bla_OXA-48-like gene was recurrently detected in both wastewater and treated water. No resistance genes were identified during the summer, whereas the bla_VIM gene was detected exclusively in spring samples. The presence of carbapenem resistance genes in the absence of cultivable coliforms suggests the persistence of extracellular DNA or viable but non-culturable bacteria, highlighting limitations inherent to conventional microbiological monitoring. Integrating classical microbiological methods with molecular assays enables a more comprehensive assessment of water quality and strengthens evidence-based decision-making within a One Health framework. Full article

Designing robust drinking water treatment schemes for eutrophic sources requires shifting from considering each treatment step separately to considering the full treatment process as a connected system. This study evaluated how treatment configuration and arrangement influence microbial community dynamics, organic carbon removal, and biological stability in a full-scale drinking water treatment plant. A Dutch treatment plant was monitored, operating two parallel lines: one conventional (coagulation, sedimentation, and rapid sand filtration) and one advanced (ion exchange, ceramic microfiltration, and advanced oxidation), both converging into granular activated carbon (GAC) filtration. Microbial and chemical water quality was assessed across treatment stages and seasons. This plant experiences periods of discoloration, taste, and odor issues, and an exceedance of Aeromonas counts in the distribution network. Advanced oxidation achieved a high bacterial cell inactivation (~90%); however, it significantly increased assimilable organic carbon (AOC) (300–900% increase), challenging biological stability. GAC filtration partially reduced AOC levels (from 70 μg Ac-C/L to 12 μg Ac-C/L) but also supported dense (10⁵ cells/mL) and diverse microbial communities (Shannon diversity index 5.83). Moreover, Gammaproteobacteria, which harbor opportunistic pathogens such as Aeromonas, persisted during the treatment. Archaea were highly sensitive to oxidative and physical stress, leading to reduced diversity downstream. Beta diversity analysis revealed that treatment configuration, rather than seasonality, governed the community composition. The findings highlight that treatment arrangement, oxidation, GAC operation, and organic and microbial loads critically influence biological stability. This study proposes integrated strategies to achieve resilient and biologically stable drinking water production when utilizing complex water sources such as eutrophic lakes. Full article

With the increasing prevalence of microplastics (MPs) and nanoplastics (NPs) in global aquatic environments, their potential ecotoxicological and health impacts have become a major concern in environmental science. Slow sand filtration (SSF) is widely recognized for its low energy demand, ecological compatibility, and operational stability; however, its efficiency in removing small or neutrally buoyant MPs remains limited. In recent years, integrating modified activated carbon (MAC) into SSF systems has emerged as a promising approach to enhance MP removal. This review comprehensively summarizes the design principles, adsorption and bio-synergistic mechanisms, influencing factors, and recent advancements in MAC-SSF systems. The results indicate that surface modification of activated carbon—through controlled pore distribution, functional group regulation, and hydrophilic–hydrophobic balance—significantly enhances the adsorption and interfacial binding of MPs. Furthermore, the coupling between MAC and biofilm facilitates a multi-mechanistic removal process involving electrostatic attraction, hydrophobic interaction, physical entrapment, and biodegradation. In addition, this review discusses the operational stability, regeneration performance, and environmental sustainability of MAC-SSF systems, emphasizing the need for future research on green and low-cost modification strategies, interfacial mechanism elucidation, microbial community regulation, and life-cycle assessment. Overall, MAC-SSF technology provides an efficient, economical, and sustainable pathway for microplastic control, offering valuable implications for a safe water supply and aquatic ecosystem protection in the future. Full article

The imbalance between water supply and demand in the arid and semi-arid regions of northwest China has become increasingly severe, highlighting the urgent need to develop and utilize unconventional water resources. Return flow, originating from canal leakage and field drainage, is widely distributed in these regions. However, as it contains a certain amount of salts, long-term use of return flow can lead to soil salinization and degradation of soil structure. Therefore, the scientific utilization of return flow has become a key issue for achieving sustainable agricultural development and efficient water use in arid areas. This study was conducted in the Yinbei Irrigation District, Ningxia, northwest China. Water samples were collected from the main and branch drainage ditches and analyzed to evaluate the feasibility of using return flow irrigation in the area. In addition, based on two years of continuous field monitoring and HYDRUS model simulations, the long-term dynamics of soil salinity under moderate return flow irrigation over the next 20 years were predicted. The results show that the total salinity of the main return ditches consistently remained below the agricultural irrigation water quality standard of 2000 mg/L, with Na⁺ and SO₄²⁻ as the predominant ions. Seasonal variations in return flow salinity were notable, with higher levels observed in spring compared to summer. Simulation results based on field trial data indicated that soil salinity displayed regular seasonal fluctuations. During the rice-growing season, strong leaching kept the salinity in the plough layer (0–40 cm) low. However, after irrigation ceased, evaporation in autumn and winter led to an increase in surface soil salinity, creating annual peaks. Long-term simulations showed that soil salinity throughout the entire profile (0–100 cm) followed a pattern of “slight increase—gradual decrease—dynamic stability.” Specifically, winter salinity peaks slightly increased during the first two years but then gradually declined, stabilizing after approximately 15 years. This indicates that long-term return-flow irrigation does not result in the accumulation of soil salinity in the plough layer. Full article

Balsam fir is an important specialty horticultural crop in eastern North America and commonly harvested for use as Christmas trees. Postharvest quality is a major challenge for producers, who are particularly concerned about postharvest needle retention. It was hypothesized that pyroligneous acid (PA) would help increase postharvest needle retention in balsam fir when supplied via xylem or foliage. This project first identified foliar spraying as the best application method, then designed a multivariate experiment with two factors. The first factor was foliar treatment (control, water, 1% PA, 2% PA, and 4% PA). The second factor was time, where branches were evaluated for needle abscission at 0, 2, 4, 6, and 8 weeks after harvest. The experiment was replicated 5 times and needle abscission, water uptake, chlorophyll, carotenoids, flavonoids, total phenolics, membrane injury, proline, and H₂O₂ production were all measured in response. Postharvest abscission reached 100% over the 8-week experiment and water uptake decreased by over 80%. Chlorophyll, proline, membrane injury, and H₂O₂ production all increased over time. Although PA did not improve needle retention compared to the control under the tested conditions, 4% PA spray increased proline concentration by 40% while decreasing membrane injury by 26%. Ultimately, PA did not consistently improve needle retention but did induce proline accumulation and membrane protection. Full article

Protecting aquatic biodiversity while ensuring reliable hydropower production and water supply remains a core challenge for both water security and biosecurity. In this PRISMA-based systematic review, we synthesize evidence from 96 studies on fish guidance and deterrence at hazardous water intakes. We examine non-physical barriers, including acoustic and light cues, electric fields, bubble curtains, and chemical stimuli, as well as physical barriers such as racks, guidance structures, and nets or screens that aim to divert fish away from intakes and toward selective passage routes. Overall, guidance and deterrence performance is strongly species- and site-specific. Multimodal systems that combine multiple cues show the highest mean guidance efficiency (~80%), followed by light-based deterrents (~77%). Acoustic, electric, and bubble barriers generally achieve intermediate efficiencies (~55–58%), whereas structural devices alone exhibit lower mean performance (~46%), with substantial variability among sites and designs. Physical screens remain effective for larger size classes but can increase head loss and debris accumulation. By contrast, non-physical systems offer more flexible, low-footprint options whose success depends critically on local hydraulics, the sensory ecology of target species, and ambient environmental conditions. We identify major knowledge gaps relating to underlying sensory and behavioral mechanisms, hydraulics-based design rules, and standardized performance metrics. We also highlight opportunities to integrate advanced monitoring and AI-based analytics into adaptive, site-specific guidance systems. Taken together, our findings show that carefully selected and tuned barrier technologies can provide practical pathways to enhance water security and biosecurity, while supporting sustainable fish passage, improving invasive-species control, and reducing ecological impacts at water infrastructure. Full article

Soybean is a key global crop for food and oil production, playing a vital role in ensuring food security and supplying plant-based proteins and oils. Accurate information on soybean distribution is essential for yield forecasting, agricultural management, and policymaking. In this study, we developed an Enhanced Chlorophyll Index (NRLI) to improve the separability between soybean and maize—two spectrally similar crops that often confound traditional vegetation indices. The proposed NRLI integrates red-edge, near-infrared, and green spectral information, effectively capturing variations in chlorophyll and canopy water content during key phenological stages, particularly from flowering to pod setting and maturity. Building upon this foundation, we further introduce a pixel-wise compositing strategy based on the peak phase of NRLI to enhance the temporal adaptability and spectral discriminability in crop classification. Unlike conventional approaches that rely on imagery from fixed dates, this strategy dynamically analyzes annual time-series data, enabling phenology-adaptive alignment at the pixel level. Comparative analysis reveals that NRLI consistently outperforms existing vegetation indices, such as the Normalized Difference Vegetation Index (NDVI), Enhanced Vegetation Index (EVI), and Greenness and Water Content Composite Index (GWCCI), across representative soybean-producing regions in multiple countries. It improves overall accuracy (OA) by approximately 10–20 percentage points, achieving accuracy rates exceeding 90% in large, contiguous cultivation areas. To further validate the robustness of the proposed index, benchmark comparisons were conducted against the Random Forest (RF) machine learning algorithm. The results demonstrated that the single-index NRLI approach achieved competitive performance, comparable to the multi-feature RF model, with accuracy differences generally within 1–2%. In some regions, NRLI even outperformed RF. This finding highlights NRLI as a computationally efficient alternative to complex machine learning models without compromising mapping precision. This study provides a robust, scalable, and transferable single-index approach for large-scale soybean mapping and monitoring using remote sensing. Full article

This study examines the hydroclimatic controls on reservoir storage dynamics in the Sinni River basin (southern Italy), with a specific focus on the Monte Cotugno dam—the largest earth-fill reservoir in Europe. Using monthly precipitation data (2000–2024) from eight gauges and standardized indicators (SPI at multiple timescales and SRI for storage), we apply robust trend, correlation, autocorrelation, and causality analyses, supported by advanced preprocessing (TFPW), to disentangle climatic influences from anthropogenic pressures. Results show a statistically significant and persistent decline in the SRI series, indicating progressive storage depletion, despite stationary or slightly positive trends in precipitation at annual and hydrologically relevant timescales. These findings highlight the dominant role of cumulative operational losses and systemic inefficiencies—rather than sustained climatic drying—as primary drivers of reservoir decline. Granger causality and lagged-correlation analyses reveal that multi-month to annual precipitation anomalies (SPI-3, SPI-6, SPI-12) exert the strongest influence on storage variations, yet the basin’s ability to convert rainfall into effective reservoir supply is severely constrained by infrastructural and management limitations. The study underscores the urgent need to integrate climate-based monitoring with infrastructural modernization and governance reforms to address the combined climatic and anthropogenic pressures increasingly affecting Mediterranean water systems. Full article

Under the combined influence of global climate change and intensified human activities, quantifying ecological compensation (EC) amounts between regions and formulating scientifically sound and rational policies have become critical strategies for addressing the imbalance between economic development and ecological conservation. This study focuses on the Yangtze River Economic Belt (YREB) as the research subject, assesses ecosystem service supply and demand (ESSD) in the years 2000, 2010, and 2020 from the perspective of the water-energy-food nexus (WEF-Nexus), identifies ecosystem service flows (ESF) between supply and demand areas, develops an integrated EC model incorporating ecological, economic, and social dimensions to estimate EC amounts, and ultimately employs the XGBoost-SHAP model to analyze the underlying driving mechanisms. The results indicate the following: (1) From 2000 to 2020, the spatio-temporal variations in the three ESSDs in the YREB were substantial. Additionally, imbalances in ESSDs were observed, predominantly in economically advanced regions. (2) A total of 183 ESFs were identified among cities within the YREB, reflecting relatively active exchanges of ecosystem services (ESs). (3) Over the past two decades, the average annual total EC of the YREB amounted to 46,866.35 million yuan, with EC capital flows occurring in 117 cities. The proportion of water area in each city constitutes the primary driver of the EC amount. The EC model based on the “water-energy-food” ecosystem service flow (WEF-ESF) proposed in this study provides a valuable reference and scientific basis for formulating EC policies among YREB cities. Full article

Groundwater is the main water source for irrigated agriculture, accounting for an increasing share of the domestic supply in the hyper-arid district of La Yarada Los Palos (Tacna, Peru); however, at the sector scale, concerns about arsenic, boron and salinity remain poorly quantified. Arsenic and boron were selected as target contaminants because of their naturally elevated concentrations associated with coastal and volcanic hydrogeological settings, and their well-documented implications for human health and irrigation suitability. This study reports a 12-month monitoring program (September 2024–August 2025) in three irrigated sectors, in which wells were sampled monthly and analyzed by inductively coupled plasma–mass spectrometry (ICP-MS) for total arsenic, boron, lithium and sodium, along with electrical conductivity, pH, temperature and total dissolved solids. The sector–month total arsenic means ranged from 0.0089 to 0.0143 mg L⁻¹, with 33 of 36 exceeding the 0.010 mg L⁻¹ drinking water benchmark recommended by the World Health Organization (WHO). Total boron ranged from 1.11 to 2.76 mg L⁻¹, meaning that all observations were above the 0.5 mg L⁻¹ irrigation guideline for agricultural use proposed by the United Nations Food and Agriculture Organization (FAO). A marked salinity gradient was observed from the inland Sector 1-BH (median Na ≈ 77 mg L⁻¹; EC ≈ 1.2 mS cm⁻¹) to the coastal Sector 3-LC (median Na ≈ 251 mg L⁻¹; EC ≈ 3.3 mS cm⁻¹), with Sector 2-FS showing intermediate salinity but the highest median boron and lithium levels. Spearman rank correlations indicate that sodium, electrical conductivity and total dissolved solids define the main salinity axis, whereas arsenic is only moderately associated with boron and lithium and is not a simple function of bulk salinity. Taken together, these results show that groundwater from the monitored wells is not safe for drinking without treatment and is subject to at least moderate boron-related irrigation restrictions. The sector-resolved dataset provides a quantitative baseline for La Yarada Los Palos and a foundation for future work integrating expanded monitoring, health-risk metrics and management scenarios for arsenic, boron and salinity in hyper-arid coastal aquifers. Full article

This study addresses the issue of water losses in drinking water distribution networks, a problem exacerbated by climate change, drought, and aging infrastructure. The research was conducted in the operational area of Frýdek-Místek, managed by Severomoravské vodovody a kanalizace Ostrava a.s., covering 59 municipalities, 1024.4 km of pipeline, and more than 32,594 service connections. The objective was to evaluate the impact of implementing the “Leakage monitor” software system (ver. 19-11-2024), which focuses on continuous monitoring of minimum night flows (Q_min), on the reduction in Non-Revenue Water (NRW). The system, deployed since 2019, enables automated data collection, remote transmission, and analysis for timely leak detection and localization using acoustic and correlator methods within district metered areas. The results confirmed a reduction in NRW from 14.6% in 2019 to 11.5% in 2024. The implementation of a “Leak monitor” has proven to be an effective tool for improving operational efficiency and ensuring both economic and environmental sustainability of water supply systems. Full article

Antibiotics have become an integral part of human life and production. The presence of sulfachloropyridazine (SCP), one of the most ubiquitous antibiotics, in water has been a growing concern owing to its long persistence and the difficulty in removing it by conventional water treatment processes. This study introduced ozone (O₃)-activated sodium percarbonate (SPC) as an innovative technique of advanced oxidation processes (AOPs), and the degradation of SCP from water by this method was thoroughly investigated. The impact of a variety of parameters, such as the dosage of SPC, the dosage of O₃, the pH value, and water matrix constituents, on the removal of SCP was evaluated with regard to the pseudo-first-order kinetic model. It was found that the removal effectiveness of SCP improved initially and then decreased with the rising dosage of SPC, with an optimal SPC dose achieved at 20 mg/L. Moreover, •OH, ${\mathrm{O}}_2^{•-}$ and ¹O₂ played important roles during SCP degradation based on radical quenching tests and electron paramagnetic resonance (EPR) tests. The SCP degradation pathways were predicted using density functional theory (DFT), which primarily involves the cleavage of S-C or S-N bonds and Smiles-type rearrangements, accompanied by hydroxylation. Furthermore, the toxicity of degradation intermediates was evaluated by the ECOSAR 1.1 software in terms of acute toxicity and chronic toxicity, and most of them exhibited lower levels of toxicity. The results can expand the research scope of SPC and reveal significant insights for SPC’s application in controlling antibiotic contamination. Full article