Search Results (1,755)

Groundwater is one of the basic requirements for life, economic and social developments in the Bazo River catchment, Rift Valley, Southern Ethiopia. In the study area, availability of water is faced with several problems, such as quality issues due to high levels of fluoride in some samples, spring scarcity in the lowlands, unprotected river water used for drinking, and high demand for good quality water. The aim of this study was to investigate the hydrogeochemical characteristics and to evaluate groundwater quality for domestic and irrigation uses. Thirty-four primary groundwater samples were collected from the field and analyzed in the water quality lab of Arba Minch University. Two water quality indices (WQI and EWQI), a variety of irrigation water quality indices, and GIS-based spatial analysis were utilized in this study. Cations were present in the descending order of Na > Ca > Mg > K > Fe, and anions were HCO₃⁻ > Cl > SO₄ > NO₃⁻ > F. Excepting two samples (BH8 and SP3), the water samples were acceptable for drinking. Sodium, TDS, and fluoride levels were over the limit of drinking water in BH8 and SP3. Rock–water interaction, cation exchange, and silicate mineral weathering were the main hydrogeochemical reactions that controlled groundwater composition in the area, based on Gibb’s diagram, chloro-alkaline indices, and major ions ratios. Groundwater facies were identified as Ca.HCO₃, Na.HCO₃ and mixed Ca-Na/Ca.Mg.Na.HCO₃ types using a Piper plot. The water quality index was computed, and its spatial variations were mapped using GIS. About 82.35% of groundwater samples were excellent for drinking use and 94.12% (SAR) of groundwater were acceptable for irrigation. These study results are useful to help develop inclusive strategies and interventions to address groundwater quality aspects in the study area, underlining the significance of managing and monitoring water resources. The findings underscore the need for effective management and monitoring strategies to ensure sustainable groundwater resources in the Bazo River catchment. Full article

This scoping review evaluates the role of vector-associated dissemination in contaminating the Philippine food supply chain with antimicrobial-resistant (AMR) Salmonella, an emerging infectious disease threat, using a One Health perspective to map the mechanisms through which insects and rodents bridge environmental reservoirs to human food systems. This scoping review was conducted and reported in accordance with the PRISMA-ScR guidelines. From 1969 records identified through systematic database searches, 52 studies met the inclusion criteria. These comprised 21 primary Philippine studies, 28 non-Philippine studies (including ASEAN-based historical baseline reports), and 3 policy/gray literature studies, prioritized to reflect tropical ecological and agricultural settings. Results suggest that intensive swine and poultry farming may contribute to the emergence of multidrug resistance (MDR) linked to genes such as bla_TEM and qnr. Evidence suggests that Salmonella persists in environmental matrices, such as manure and irrigation water, and that synanthropic vectors, including Rattus rattus and various fly species, potentially serve as biological and mechanical bridges in transmission. Clinical data reveal an alarming trend toward invasive non-typhoidal salmonellosis (iNTS) showing reduced susceptibility to cephalosporins and fluoroquinolones. Despite these findings, major evidence gaps remain, particularly regarding the prevalence of vector-borne Salmonella in pre-harvest produce. Consequently, mitigation requires a One Health framework that integrates non-antibiotic interventions, pest management to disrupt transmission pathways, and rapid diagnostic tools, such as loop-mediated isothermal amplification (LAMP), to enhance market surveillance. Full article

Overexploitation of groundwater resources poses a critical challenge in major agricultural regions worldwide, yet how confined and unconfined aquifers respond differentially to governance interventions remains poorly understood. This study presents a comparative assessment of hydrochemical evolution and nitrate contamination dynamics in the Weishan Irrigation District, Shandong Province, China, contrasting pre-governance conditions (2011) with post-governance status (2022–2023) following comprehensive overexploitation control. By integrating hydrochemical characterization with stable isotope tracers (δ¹⁸O, δD, δ¹⁵N-NO₃⁻, δ¹⁸O-NO₃⁻) and Bayesian mixing models (MixSIAR), we reveal fundamentally contrasting aquifer responses to regulation. The unconfined aquifer exhibited continued degradation under persistent agricultural influence, characterized by elevated sodium, nitrate, and bicarbonate concentrations. In sharp contrast, the confined aquifer demonstrated substantial recovery, with major ion concentrations declining markedly, hydrochemical facies restored toward a pristine state, and overall water quality improving significantly to achieve full compliance with the highest-quality standards by 2023. These divergent trajectories indicate that regulatory interventions effectively restored aquitard barrier integrity, thereby shielding the confined aquifer from surface contamination, whereas the unconfined aquifer remained vulnerable to agricultural pollution. Isotope-constrained Bayesian modeling identified soil organic nitrogen, chemical fertilizers, manure/sewage, and industrial wastewater as dominant nitrate sources, with isotopic evidence confirming that the unconfined aquifer receives mixed recharge from Yellow River water and precipitation under contemporary contamination, while the confined aquifer maintains independent, pollution-free recharge. These findings demonstrate that overexploitation control can effectively rehabilitate confined aquifer systems by reestablishing natural hydrogeological barriers, but unconfined aquifers require targeted agricultural pollution mitigation. The contrasting responses highlight the necessity of aquifer-specific management strategies in irrigation-dependent regions, advancing theoretical understanding of how regulatory measures differentially affect multi-layered groundwater systems and providing a scientific basis for precision groundwater governance. Full article

This review evaluates the current state of knowledge on the use of wood fibres and related woody materials as partial substitutes for peat in substrates used for forest nursery production, with particular emphasis on container seedlings. The review was prepared as a structured narrative synthesis of the available literature, focusing on substrate composition, physical and chemical properties, tree seedling growth, root development, water regime, fertilisation, operational handling, economic aspects and remaining research needs. The available evidence shows that wood fibres are technically promising components of peat-reduced growing media, but their performance depends strongly on the raw-material origin, processing method, substrate proportion, tree species, and cultivation management. The most reliable results have been obtained with partial substitution systems, whereas peat-free solutions remain species-specific and require careful optimisation of irrigation, nitrogen supply, pH control, and substrate quality. Although wood-based materials may improve resource efficiency and, under favourable local conditions, reduce substrate costs, wider implementation is constrained by variable material quality, limited standardisation and insufficient operational-scale validation. The main remaining research need is to define species-specific application thresholds and management protocols and to link nursery performance with outplanting success and full production economics under commercial conditions. Full article

Sustainable rice production requires management strategies that reduce drainage-related nitrogen export while maintaining grain yield under increasingly constrained water and labor conditions. This study evaluated a controlled-irrigation-based integrated management regime in direct-seeded and mechanically transplanted rice under production-field conditions in the lower Yangtze River region, China. The optimized regime combined threshold-based controlled irrigation, functional basal fertilizer, and key-stage foliar regulation, whereas the traditional treatments followed local conventional flooding and fertilization practices. Drainage-related total nitrogen (TN) export was mainly associated with rainfall or irrigation-overflow events after fertilization. Compared with the corresponding traditional treatments, optimized management reduced irrigation input by 28.5% and 26.4%, cumulative drainage volume by 54.8% and 46.5%, and monitored-event TN export load by 63.6% and 60.0% in mechanically transplanted and direct-seeded rice, respectively. Grain yields reached 10,088 and 9870 kg ha⁻¹ in Opt-MT and Opt-DS, increasing by 6.5% and 7.2%, respectively. The optimized treatments also reduced chalky grain rate and chalkiness degree, although head rice rate did not improve synchronously. These findings provide field-based evidence that integrated management may help coordinate monitored drainage-related nitrogen-export mitigation, water-saving irrigation, and yield maintenance under similar production-field conditions. Full article

Rice production is under increasing threat from adverse climatic trends that exacerbate water scarcity and compromise food safety. The need to transition toward water-saving irrigation is urgent, as is the requirement of addressing the dual burden of selenium (Se) deficiency and arsenic (As) toxicity. This 3-year field study (2020–2022) is the first to evaluate the effects of integrated water-saving irrigation. Permanent flood irrigation (Flood) or alternate wetting and drying was used, in which fields were reflooded when the soil matric potential reached −20 kPa (Reflood-20) and −70 kPa (Reflood-70); the effects of foliar Se biofortification at 15 g Se ha⁻¹ with sodium selenate (15-Se) or no Se (No-Se) on rice production and Se and As accumulation were also investigated. The results identified the Reflood-20 regime as the optimal strategy, achieving 36% water savings without significant grain yield penalties while enhancing grain quality. Foliar Se application successfully increased the dehulled grain Se content by 10.7-fold, effectively meeting human dietary requirements. The As contents were decreased by 27.6% due to water restriction, and an additional 10% loss was observed because of Se supplementation. Analysis of the straw also showed a 23.5% decrease in As and a 5.7-fold increase in Se. Consequently, the synergy between moderate deficit irrigation and Se biofortification provides a robust, cost-effective framework for the large-scale production of safer, nutrient-dense rice, reconciling resource efficiency with food security. Full article

Transitioning from conventional wastewater treatment to circular wastewater management requires novel technologies that enable resource recovery, energy efficiency, and resilience under variable conditions. Within the NAMOR project, hybrid microalgae–bacteria Membrane PhotoBioReactors (MPBRs) are assessed as a sustainable solution for decentralized wastewater treatment and reuse. This study focuses on screening and optimizing mixed microalgae–bacterial consortia to treat municipal wastewater streams in the Mediterranean region, with an emphasis on achieving high nutrient removal, biomass productivity and robustness. A diverse set of strains will be evaluated under controlled temperature, light and nutrient regimes to enhance the symbiotic synergy between photosynthetic microalgae and heterotrophic bacteria, while minimizing aeration demand. Based on these results, a pilot demo in Lagadas, Greece, will integrate the optimized consortia into a moving-bed PBR equipped with polymeric carriers and membrane filtration for advanced effluent polishing, intended to produce reclaimed water for irrigation and biomass for valorisation into fertilizers or biogas. Full article

Understanding how irrigation water management shapes crop performance is critical for improving productivity and resource-use efficiency in peri-urban agriculture. This study investigated the socio-technical factors driving sprinkler system abandonment and assessed how irrigation water variability influences vegetable yield variability at two market gardening sites (Bogdin and 14 Yaar) in Ouagadougou, Burkina Faso. Survey data from 50 farmers and field measurements of soil properties, irrigation water application, and lettuce yield were analyzed using descriptive statistics, Spearman correlations, and principal component analysis. More than 80% of farmers had ceased using the sprinkler system within two years of installation, 76% reported major equipment failures, and 70% expressed willingness to re-adopt an improved system. Irrigation dose and yield showed considerable variability across sites (CV = 20.9–42.3% and 36.4–44.0%, respectively). At 14 Yaar, irrigation dose was strongly associated with yield (r = 0.862, p = 0.006), indicating that uneven water application was a major constraint on productivity. At Bogdin, where irrigation was more uniform, no single soil or water variable dominated yield variability. Although soil fertility variables contributed to multivariate patterns, nutrient–yield correlations were not statistically significant under the available sample size, and their potential influence on yield requires confirmation with larger datasets. Overall, operational constraints, equipment failures, and inadequate support services contributed to sprinkler system abandonment, while variability in manual water application was associated with variability in crop productivity. These findings highlight the need for irrigation strategies that are both technically robust and adapted to farmers’ realities. Full article

The rising global population has heightened food demand, placing pressure on agricultural systems, particularly in water-scarce regions such as South Africa. Smallholder farmers, essential to the sector, face climatic variability and resource constraints, necessitating innovative solutions to enhance sustainability and productivity. This study evaluates unmanned aerial vehicles (UAVs) for generating spatially explicit evapotranspiration (ET) estimates in a small-scale sugarcane field, supporting precision water management. Vegetation indices (VIs) derived from UAV-based multispectral imagery were used to predict actual ET (ET_a) and validated against eddy covariance measurements. Five models were assessed, including Normalised Difference Vegetation Index (NDVI)-based and Enhanced Vegetation Index (EVI)-based approaches. Machine learning was used to relate crop coefficients (K_c) to NDVI, enabling improved estimation. The two-band EVI (EVI2) model achieved the highest accuracy, with an R² of 0.63, an RMSE of 0.67, and an MAE of 0.52. ET-VI approaches, particularly EVI2, require lower data and technical complexity, making them suitable for smallholder systems. However, reducing dependence on in situ data remains essential to improve accessibility of remote sensing approaches for agricultural water management in resource-limited environments. These findings demonstrate the potential of UAV-based ET_a modelling to support field-scale irrigation decision-making while highlighting the need for further refinement to improve operational applicability across diverse smallholder farming contexts and beyond. Full article

Increasing pressure on surface water resources in intensive agricultural regions has driven the search for sustainable alternatives for irrigation supply, especially in areas where water quality limits crop safety and export opportunities. In this context, riverbank filtration (RBF) systems offer a nature-based solution by utilizing physical, chemical, and biological processes associated with river–aquifer exchange. However, their implementation depends on suitable site selection supported by hydrogeological, geomorphological, and hydraulic criteria. This study developed an integrated methodology to identify zones with potential for implementing RBF systems in the Roldanillo–Unión–Toro irrigation district, located in northern Valle del Cauca, Colombia. This region requires irrigation water over 10,256 ha of agricultural land (mainly sugarcane, maize, grapes, and guava). We combined geophysical methods (vertical electrical soundings, 2D electrical resistivity tomography, and passive seismic), geotechnical methods (CPTu tests), and hydraulic characterization of the river reach to evaluate subsurface stratigraphy, preliminary hydrogeological suitability, inferred river–aquifer connectivity conditions, and channel stability. The evaluation covered four sectors along an approximately 21 km stretch of the Cauca River’s left-bank alluvial valley. The results revealed pronounced lateral and vertical heterogeneity of alluvial materials. However, the “El Palmar” sector was identified as the best-supported priority sector for future RBF validation, due to the presence of profile-scale evidence of potentially permeable sandy and gravelly units with intermediate resistivity values (52–61 Ω·m), favorable stratigraphic organization, and stable river-reach conditions during the field campaign. In contrast, the other three sectors (La Esperanza, Candelaria, and Cayetana) showed more fine-grained sediments with deeper permeable strata. River-flow measurements during the July 2025 field campaign indicated high discharge conditions at the evaluated reach, while river-channel observations showed active fine-sediment transport; these findings provide hydraulic and sedimentary context for the future evaluation of induced infiltration and potential clogging, but do not constitute direct evidence of river–aquifer exchange. This study highlights the value of integrated screening approaches for prioritizing candidate RBF sites in agricultural alluvial settings, while indicating that pumping tests, piezometric monitoring, hydraulic-gradient analysis, and water-quality validation remain necessary before engineering implementation. Full article

Reusing wastewater in agriculture is essential due to water scarcity but requires treatment technologies that preserve soil biological integrity. This study evaluated the impact of irrigation with wastewater treated by cold atmospheric plasma (CAP; 60 min exposure) on the soil microbiome during Festuca rubra L. and Sinapis alba L. cultivation. The experimental design included various CAP-wastewater dilutions evaluated in two replicates (n = 2), with microbial shifts assessed via 16S rRNA gene sequencing. CAP treatment reduced non-purgeable organic carbon (NPOC) while enriching the water with nitrogen, which significantly stimulated S. alba root growth. Metagenomic analysis confirmed high microbiome stability. Dominant phyla (Proteobacteria and Actinobacteriota) remained stable, and beta-diversity indices showed no statistically significant ecological shifts (R² = 0.420, p = 0.121). Furthermore, CAP-treated irrigation promoted beneficial taxa, specifically the genus Bacillus. These findings demonstrate that CAP wastewater treatment is a safe, environmentally responsible strategy for wastewater reclamation. It successfully supports nutrient cycling and agricultural production without compromising soil microbial homeostasis or health, offering a viable solution aligned with the principles of a circular economy. Full article

In many orographically complex monsoon basins, rain gauge networks are sparse and lack the long-term continuous records required for reliable precipitation probability analysis. Traditional regional frequency analysis assumes spatially uniform precipitation across the analysis zone, which is inadequate for basins with steep rainfall gradients and strong seasonal variability. Gridded precipitation products (GPPs) provide spatially continuous, long-term records that enable grid-cell-level probability distribution fitting. However, GPPs may exhibit local biases and errors, and statistical evaluation against gauge observations is necessary before application. This study was conducted in the Phetchaburi–Prachuap Khiri Khan River Basin, western Thailand, a region with steep orographic and coastal rainfall gradients. Four GPPs, namely CHIRPS, CHELSA, WorldClim, and PERSIANN-CCS-CDR, were evaluated against gauge observations. The best-performing product, after monthly bias correction, was then used to generate spatially continuous monthly exceedance probability maps using grid-cell gamma distribution fitting. CHELSA showed the best overall performance across all evaluation metrics (correlation coefficient (r) = 0.908, percent bias (PBIAS) = 7.0%, root mean square error (RMSE) = 48.3 mm), passing the Kolmogorov–Smirnov (KS) goodness-of-fit test at all 96 station-months. CHIRPS and WorldClim showed satisfactory overall performance but exhibited localized biases in complex terrain, whereas PERSIANN-CCS-CDR substantially overestimated wet-season rainfall, limiting its suitability for this basin. Spatial precipitation patterns varied markedly between monsoon regimes, shifting from a dominant west-to-east orographic gradient during the southwest monsoon to a less differentiated advective pattern during the northeast monsoon. Furthermore, analysis at the 75% exceedance probability level showed that mean-based effective rainfall overestimated reliable water supply in high-variance months, leading to underestimation of supplemental irrigation demand. The generated maps provide spatially explicit dependable rainfall estimates across the basin, supporting probabilistic agricultural water management at multiple planning scales in orographically complex monsoon basins. Full article

Sustainable irrigation planning under increasing water scarcity requires quantitative optimization tools to balance land and water resources. This study develops a linear programming (LP)-based framework to determine optimal cropping patterns under variable seasonal water availability in three irrigation projects in Lao PDR: Nam Tong 2 (1000 ha; ≈48.16 million m³ (MCM)), Nam Hin (80 ha; ≈0.73 MCM), and Xe Salalong (1530 ha; ≈30.80 MCM). Six major crops were analyzed for each project, with crop water requirements ranging from 4000 to 12,000 m³ ha⁻¹ and gross revenues from 1200 to 41,322 US$ ha⁻¹. Eight irrigation scenarios were constructed by combining land suitability (suitable vs. unsuitable), crop water requirement levels, and gross revenue assumptions. The model maximizes total gross revenue subject to seasonal water and land constraints. The results indicate that under limited water availability (e.g., 5.35–6.20 MCM in Nam Tong 2), crops with lower water demand (≤6000 m³ ha⁻¹) and higher economic return per unit of water are prioritized, improving water-use efficiency. As water availability increases, high-value but water-intensive crops expand until land suitability becomes the dominant constraint. Expanding irrigation on unsuitable land produces diminishing economic returns. The framework enhances the realism of irrigation planning and supports economically efficient, water-sustainable crop allocation in water-scarce regions. Full article

The use of sophisticated software for greenhouse microclimate analysis often requires advanced modelling expertise and significant computational effort, which may not always be available to greenhouse designers. This study proposes an integrated and modular workflow aimed at supporting greenhouse design through coupled thermal and evapotranspiration simulations. The design methodology is based on three steps. In the initial phase, the greenhouse environmental conditions are evaluated through the implementation of a dynamic thermal analysis, which is conducted by the DesignBuilder software (version 4.2). Subsequently, a plant evapotranspiration model is employed in MATLAB/Simulink (version R2025b) to evaluate crop transpiration, moisture production, and irrigation water consumption. In the final phase, the simulated moisture production is used to estimate the required ventilation rates and to support the sizing of greenhouse systems, including irrigation and HVAC components. Plant moisture production is a crucial factor in determining the sizing of greenhouse subsystems, such as the irrigation system, the ventilation rate, and the HVAC system. Nonetheless, the implementation of the evapotranspiration model necessitates a bespoke calibration to a case study. Indeed, the proposed models are more generally applicable and must be adapted to real-world applications. The methodology was applied to a small greenhouse used for the cultivation of aeroponic lettuce (Lactuca sativa cv. Romana) in a Mediterranean environment. The aim of the study was to explore the potential of the proposed integrated modelling framework to estimate annual irrigation water demand and the minimum ventilation rate required to mitigate excess moisture production, using a coupled MATLAB/Simulink implementation. The proposed approach should be interpreted as an exploratory design-support methodology rather than a fully validated predictive model, intended to investigate system behaviour under the specific conditions of the case study. Full article

Efficient irrigation management requires reliable information on soil water content, yet low-cost capacitive sensors often lack proper calibration. This study evaluates the metrological performance of two DF Robot probes, SEN0193 (S1) and SEN0308 (S3), under controlled variations in porous media properties. Glass beads of three size classes (<50 µm, 70–110 µm, and 400–600 µm) were used to simulate fine, medium, and coarse textures. Sensors were tested at four water contents (0, 10, 20, and 30%) and four salinity levels (0, 4, 8, and 16 g NaCl L⁻¹). Results show that the manufacturer-recommended air/water calibration is unsuitable for soils or porous media; calibration should instead be performed under dry and saturated conditions specific to the medium. S1 exhibited stable and homogeneous responses, with intra-unit CV ≤ 2%, but moderate calibration accuracy (R² = 0.68–0.80; RMSE = 8.9–12.9% VWC across textures). S3 showed a wider signal range (80–90% larger than S1), better fit in coarse texture (R² = 0.96; RMSE = 3.5% VWC), but higher unit-to-unit variability (CV = 6–14%) and performance degradation in fine and saline media. Although these sensors cannot provide accurate absolute quantification, their ability to track moisture trends makes them useful for irrigation management, provided calibration accounts for medium texture and salinity. Full article