Search Results (711)

Terrestrial water storage includes soil water storage, groundwater storage, surface water storage, snow water equivalent, plant canopy water storage, biological water storage, etc., which can comprehensively reflect the total change in water volume during processes such as precipitation, evapotranspiration, runoff, and human water use in the basin hydrological cycle. The Gravity Recovery and Climate Experiment (GRACE) satellite provides a powerful tool and a new approach for observing changes in terrestrial water storage and groundwater storage. The North China Plain (NCP) is a major agricultural region in the northern arid area of China, and long-term overexploitation of groundwater has led to increasingly prominent ecological vulnerability issues. This study uses GRACE and Global Land Data Assimilation System (GLDAS) hydrological model data to assess the spatiotemporal patterns of groundwater drought in the NCP and its various sub-regions from 2003 to 2022, identify the locations, occurrence probabilities, and confidence intervals of seasonal and trend mutation points, quantify the complex interactive effects of multiple climate factors on groundwater drought, and reveal the propagation time from groundwater drought to agricultural drought. The results show that: (1) from 2003 to 2022, the linear tendency rate of groundwater drought index (GDI) was −0.035 per 10 years, indicating that groundwater drought showed a gradually worsening trend during the study period; (2) on an annual scale, the most severe groundwater drought occurred in 2021 (GDI = −1.59). In that year, the monthly average GDI in the NCP ranged from −0.58 to −2.78, and the groundwater drought was most severe in July (GDI = −2.02); (3) based on partial wavelet coherence, the best univariate, bivariate for groundwater drought were soil moisture (PASC = 19.13%); and (4) in Beijing, Tianjin and Hebei, the propagation time was mainly concentrated in 1–5 months, with average lag times of 2.87, 3.20, and 2.92 months, respectively. This study can not only reduce and mitigate the harm of groundwater drought to agricultural production, social life, and ecosystems by monitoring changes in groundwater storage, but also provide a reference for the quantitative identification of the dominant factors of groundwater drought. Full article

Microplastics (MPs) are increasingly reported as contaminants in sewage sludge, with wastewater treatment plants retaining approximately 10³–10⁶ particles kg⁻¹ of dry sludge. Anaerobic digestion (AD), widely applied for sludge stabilization and energy recovery, does not consistently remove these particles; MPs frequently persist and, at elevated or sensitive loadings, have been shown to affect methane production, microbial communities and sludge quality. In parallel, thermal hydrolysis and related pretreatments are being implemented at full scale to enhance sludge biodegradability, exposing embedded MPs to high temperature and pressure prior to AD. This review compiles and analyzes experimental studies on MPs in sludge pretreatment and AD systems, with an emphasis on how pretreatment severity, MP type, particle size and concentration influence MP transformation and process performance. Reported data indicate that intensified pretreatment accelerates MP aging, causing fragmentation, oxidative surface modification and additive release, while subsequent AD generally induces limited further MP degradation but can be negatively affected through reduced methane yields, shifts in microbial consortia and altered behavior of co-contaminants. Mechanisms implicated include leaching of plastic additives, enhanced oxidative and physiological stress, and formation of plastisphere biofilms that perturb syntrophic interactions. Mitigation approaches, including optimized thermal hydrolysis–AD configurations and the use of carbonaceous sorbents, are assessed with regard to their effects on MP-associated inhibition and their practical constraints. Analytical limitations, uncertainties in MP mass balances and environmental fate, and key research needs for evaluating MP risks and designing MP-resilient sludge treatment and biosolid management strategies are identified. Full article

Temperature plays a vital role in plant metabolism, and effective crop temperature appears to be influenced by variables related to climate change. While extreme weather events are widely discussed, the effects of moderate temperature changes pose consistent yet underexplored challenges for farmers. The “growing degree days” (GDD) also termed “heat unit”, is the most widely used approach in agricultural and ecological studies to quantify the relationship between temperature and plant development. This review provides a comprehensive examination of GDD methodology as applied to horticultural crop production, specifically from initial fruit development to fruit maturity, and postharvest. It is the first integrated synthesis of the conceptual evolution, methodological refinement, and broad application of GDD, thereby highlighting the need to optimize GDD approaches in light of emerging technological tools. While the GDD model is valuable for predicting crop development based on heat accumulation, it has limitations in capturing the effects of other environmental factors. Additionally, air temperature may not provide precise data on each plant organ. Recent advances in remote sensing, such as the integration of thermal imaging, RGB cameras, and lidar have enabled the measurement of spatially resolved temperature distribution within crop canopies, including fruit surface temperature. Recent advances, highlighted in the literature, suggest that integrating sensor innovations with machine learning approaches holds high potential for improving the precision of modeling temperature-dependent growth responses and their interactions with other environmental variables. By addressing these challenges and expanding its applications, GDD can continue to serve as an essential tool in promoting sustainable horticultural practices and adapting to global warming. Full article

The widespread use of agrochemicals, including inorganic and organic pesticides and fungicides, has contributed to the persistence of hazardous residues in agricultural environments, particularly through their accumulation in plastic packaging and containers. High-density polyethylene (HDPE), polypropylene (PP), and other polymer types commonly employed for agrochemical storage and transport retain significant quantities of active substances even after standard rinsing procedures. This phenomenon raises concerns over improper disposal practices, environmental contamination, and potential ecotoxicological impacts. Recent studies demonstrate that both inorganic and organic pesticide residues exhibit strong interactions with plastic polymers, influenced by factors such as polymer chemistry, surface aging, pH, ionic strength, and dissolved organic matter. These interactions not only delay degradation but also facilitate secondary release into soils and aquatic systems, where they may impair soil microorganisms, alter plant physiology, and disrupt aquatic food webs, including phytoplankton, fish, and microbial assemblages. Despite regulatory frameworks and container management schemes in some regions, major knowledge gaps remain regarding the long-term fate of pesticide residues on plastics, their transfer to ecosystems, and cumulative effects on agroecosystem sustainability. This review synthesizes current evidence on the chemical characteristics of pesticide residues in plastic packaging, their environmental mobility, and ecotoxicological effects. It further identifies urgent research needs, including long-term field assessments of polymer–pesticide interactions, improved recycling technologies, and the development of safer container designs. Effective management strategies, coupled with strengthened international stewardship programs, are essential to reduce risks to environmental health, agricultural productivity, and human safety. Full article

Carbon dots (CDs) are promising for agro-environmental applications; however, clear connections between synthesis, photophysical properties, size, and biosafety are often not well established. In this study, we map these relationships for glucose–arginine CDs (GA-CDs). By using microwave and hydrothermal routes at precursor ratios of 1:3, 1:9, and 1:15, we produced sub-10 nm nanoparticles (analyzed by dynamic light scattering and atomic force microscopy) that exhibit tunable absorption and emission properties, as well as surface properties (demonstrated through UV–Vis spectroscopy, 3D photoluminescence, and FTIR analysis). The hydrothermal 1:9 condition yielded the narrowest size distribution and red-shifted photoluminescence. Across biological models spanning plants, insects, plant-growth-promoting bacteria (PGPR), and human cells, GA-CDs were well tolerated, with no adverse changes detected in plant stress markers, aphid feeding behavior or fecundity, or PGPR growth. In A549 cells, viability remained stable up to a concentration of 0.125 mg mL⁻¹, while exposure to 0.5 mg mL⁻¹ reduced viability, establishing a practical operating range. These results provide a clearer picture of how the structure and properties of carbon dots derived from arginine and glucose are correlated to their safety. The GA-CDs are, therefore, useful, and traceable tools for agro-environmental research. The findings support their use as biocompatible nanomaterials for studying interactions among plants, insects, and microbes in agriculture. Full article

Plant-derived nanocellulose particles, such as cellulose nanofibrils (CNFs) and cellulose nanocrystals (CNCs), are becoming increasingly popular for a wide range of applications. In particular, when they are employed as rheology modifiers and/or fillers, a choice between CNFs and CNCs is often not obvious. Here, we present the results of a comparative study on the rheological properties of suspensions and gels of carboxymethylated CNFs and CNCs with the same surface chemistry, surface density of charged groups, and thickness. We demonstrate that, at the same weight concentration, CNF suspensions have much higher viscosity and storage modulus, which is due to their longer length providing many entanglements. However, when comparing at the same nanoparticle concentration relative to C*, the situation is reversed: viscosity and storage modulus of CNCs appear to be much higher. This may be due in particular to the higher rigidity and intrinsic strength of highly crystalline CNCs. The gel points for CNF and CNC suspensions (without crosslinker) were compared for the first time. It was found that in the case of CNFs, the gel point occurs at a 3.5-fold lower concentration compared to that of CNCs. Hydrogels were also obtained by crosslinking negatively charged nanocellulose particles of both types by divalent calcium cations. For the first time, the thermodynamic parameters of the crosslinking of carboxymethylated CNFs by calcium ions were determined. Isothermal titration calorimetry data revealed that, for both CNFs and CNCs, crosslinking is endothermic and driven by increasing entropy, which is most likely due to the release of water molecules surrounding the interacting nanoparticles and Ca²⁺ ions. The addition of CaCl₂ to suspensions of nanocellulose particles leads to an increase in the storage modulus; the increase being much more significant for CNCs. Physically crosslinked hydrogels of both CNFs and CNCs can be reversibly destroyed by increasing the shear rate and then quickly recover up to 85% of their original viscosity when the shear rate decreases. The recovery time for CFC networks is only 6 s, which is much shorter than that of CNC networks. This property is promising for various applications, where nanocellulose suspensions are subjected to high shear forces (e.g., mixing, stirring, extrusion, injection, coating) and then need to regain their original properties when at rest. Full article

Electrostatic technology has emerged as a crucial tool for sustainable agricultural development due to its multifunctional characteristics. However, systematic and specialized investigations into its mechanism of action and application principles across diverse agricultural scenarios remain insufficient. Here, this review innovatively constructs a spatial scale classification framework and categorizes it into macroscale spray engineering and microscale plant biostimulation. At the macroscale, electrostatic spraying leverages charged droplets’ properties (high surface charge density, strong electrostatic interaction, enhanced adsorption) to improve canopy deposition efficiency and reduce agrochemical drift losses. At the microscale, electrostatic fields induce electron/ion directional movement, providing non-contact stimulation to regulate plant physiological processes such as seed germination and nutrient uptake. We systematically summarize the latest research progress in electrostatic spraying and electrostatic biostimulation, and further compare them in terms of their fundamental mechanisms, targets, and stages of technological development. Finally, the current limitations and challenges for each technology are overviewed and the forward perspective for the efficient application of electrostatics in agriculture are outlined. This review provides theoretical references and technical guidelines for the application research of electrostatic spraying and electrostatic biostimulation, holding significant importance for promoting the standardized development of electrostatic technology in sustainable and precision agriculture. Full article

Concrete-lined river channels are generally assumed to prevent groundwater exchange, functioning as inert conduits that isolate surface flow. Along the Upper Los Angeles River of Southern California, United States, however, field observations show that during dry summer months, groundwater seepage contributes nearly half of the dry-weather flow to a 9.5-km concrete-lined reach above Sepulveda Basin. This baseflow substantially modifies river chemistry, diluting some solutes while enriching others. To characterize these interactions, hydrochemical sampling was conducted in summer 2022, with additional selenium and tritium analyses from 2024 to 2025, covering tributaries, river sites, groundwater seeps, wastewater discharges, and tap water. Analyses included major ions, nutrients, selenium, and tritium. Upstream tributaries were highly saline (TDS ≈ 1670 mg/L; sulfate up to 980 mg/L; chloride ≈ 280 mg/L), whereas groundwater was moderately saline (TDS 990 to 1765 mg/L) but contained elevated nitrate-nitrogen (5.8 to 12.9 mg/L) and selenium (4.5–44.0 µg/L). Mixing analysis indicated that approximately 45% of the river’s dry-weather flow (~70.5 L/s) originated from groundwater, increasing riverine selenium above the 5 µg/L aquatic-life criterion. Downstream, where the concrete lining ends, wastewater inflows from the Donald C. Tillman Water Reclamation Plant reduced salinity but introduced additional nitrate-nitrogen. The results reveal a three-part sequence; saline tributary inputs at the headwaters, groundwater-driven nitrate and selenium enrichment within the lined reach, and effluent dilution downstream. These findings demonstrate that even concrete-lined channels can host active groundwater–surface water exchange, highlighting the need to incorporate such interactions in urban river management and channel design. Full article

This paper investigates the integration of hydropower and solar energy within the Lower Olt River cascade as a pathway toward sustainable energy generation in Romania. The study focuses on the conceptual design of future hybrid power plants consisting of existing hydropower facilities where floating photovoltaic panels are proposed to be installed on the reservoir’s surfaces. An estimation of electricity production from both sources was performed, followed by the formulation of a trading strategy for the July–September 2025 period. The paper also explores the interaction between tactical and strategic management in hydropower operation and planning, describing how forecasting and decision-making processes are structured within the institutional framework. Finally, results for the selected hydropower plants demonstrate the positive influence of floating photovoltaic deployment on company performance, the national energy mix, and the overall sustainability of energy generation in Romania. Full article

Investigating ecological irrigation risks associated with mine water utilization is of great significance for alleviating water resource shortages in arid mining regions of western China, thereby supporting efficient coal extraction and coordinated ecological development. In this study, a representative mining area in Xinjiang was investigated to reveal the evolution patterns of mine water quality under arid geo-environmental conditions in western China and to systematically assess environmental risks induced by ecological irrigation. Surface water, groundwater, and mine water samples were collected to study ion ratio coefficients, hydrochemical characteristics, and evolution processes. Based on this, a multi-index analysis was employed to evaluate ecological irrigation risks and establish corresponding risk control measures. The results show that the total dissolved solids (TDS) of mine water in the study area are all greater than 1000 mg/L. The evolution of mine water quality is mainly controlled by water–rock interaction and is affected by evaporation and concentration. The main ions Na⁺, Cl⁻, Ca²⁺, and SO₄²⁻ originate from the dissolution of halite, gypsum, and anorthite. If the mine water is directly used for irrigation without treatment, the soluble sodium content, sodium adsorption ratio, salinity hazard, and magnesium adsorption ratio will exceed the limits, leading to the accumulation of Na⁺ in the soil, affecting plant photosynthesis, and posing potential threats to the groundwater environment. Given the evolution process of mine water quality and the potential risks of direct use for irrigation, measures can be taken across three aspects: nanofiltration combined with reverse osmosis desalination, adoption of drip irrigation and intermittent irrigation technologies, and selection of drought-tolerant vegetation. These measures can reduce the salt content of mine water, decrease the salt accumulation in the soil layer, and lower the risk of groundwater pollution, thus reducing the environmental risks of ecological irrigation with mine water. The research will provide an important theoretical basis for the scientific utilization and management of mine water resources in arid areas by revealing the evolution law of mine water quality in arid areas and clarifying its ecological irrigation environmental risks. Full article

A novel bacterial strain was isolated from the roots of Suaeda japonica, a halophytic plant inhabiting tidal zones. Phylogenetic, genomic, and phenotypic analyses identified the isolate as a novel species within the genus Paraburkholderia, for which the name Paraburkholderia suaedae sp. nov. is proposed. The strain exhibits multiple plant growth-promoting traits, including the production of 1-aminocyclopropane-1-carboxylic acid, indole-3-acetic acid, and siderophore, along with the ability to fix nitrogen and solubilize phosphate. Genomic analysis revealed genes associated with enhanced root surface adhesion and rhizosphere survival, such as those involved in thiamine biosynthesis and transport, and biofilm formation via poly-β-1,6-N-acetyl-D-glucosamine (PGA) synthesis. These features suggest the strain’s potential for persistent colonization and beneficial interaction with host plants. Although its direct impact on plant growth has not yet been experimentally validated, the genetic and biochemical evidence supports its potential application in agriculture. The objective of this study was to conduct a polyphasic taxonomic characterization of a novel strain DGU8^T isolated from the roots of the halophyte Suaeda japonica, and to assess its potential as a plant growth-promoting agent, particularly its tolerance to drought-related osmotic stress. Full article

This study explores the health status of veteran Zelkova serrata trees (average age 300 years) in the Pohang region in the context of long-term climatic trends and local environmental variability. Eleven nationally designated veteran trees were monitored using physiological indicators Soil Plant Analysis Development (SPAD) values and live crown ratio (LCR), internal structural assessment (sonic tomography-derived decay ratio), and environmental parameters including meteorological records and Landsat-derived Land Surface Temperature (LST) data from 2000 to 2025. While recent years showed localized heat-extreme events, most sites displayed spatially heterogeneous yet gradually increasing LST trends, with 2024 recording the highest values at more than half the locations. Tree vitality differences were more strongly associated with site specific microclimatic conditions than with uniform long-term climate shifts: trees in cooler or less urbanized zones showed higher SPAD values and lower decay levels, whereas those in warmer, edge-influenced sites exhibited signs of physiological stress. The results indicate that rising summer surface temperature—and their interaction with atmospheric drying—intensify water-stress impacts, but the actual tree responses are modulated by local land-cover and soil stability contexts. These findings underscore the need for integrated, multi-scale assessment of veteran tree health and suggest that conservation practices should incorporate microclimate-based intervention strategies. Full article

Niobium (Nb), a transition element, has been applied mainly as steel additive, among other cutting-edge applications. Nb is mainly produced from pyrochlore-containing ores, dominated by mines at Araxá, Catalão (both from Brazil), and Niobec (Saguenay Region, QC, Canada). At these plants, flotation is employed as the main beneficiation method that all plants apply direct pyrochlore flotation; Catalão and Niobec apply additional reverse flotation prior to pyrochlore flotation. During flotation, depressants are added to improve selectivity, which highlights their importance to Nb mineral flotation. However, most of the available studies related to Nb mineral flotation focus on collectors; the knowledge on depressants is limited. In the present work, various depressants, including sodium silicate, oxalic acid, F100, starch, carboxymethyl cellulose (CMC), and chitosan, are compared for pyrochlore flotation at pH 7 in the presence of sodium oleate and dodecylamine (DDA) collectors. The results are compared with common gangue minerals, including dolomite, calcite, and hematite. It was observed that the performance of depressants is related to the collector applied, which was justified by the mineral surface charge after depressant adsorption and the charge of the collector. Among the tested combinations, 5 kg/t F100 + 2 kg/t DDA and 5 kg/t CMC + 2 kg/t DDA showed potential selectivity toward pyrochlore and hematite, whereas both carbonate minerals could be successfully depressed. Zeta potential measurement and X-ray photoelectron spectroscopy were applied to understand the interaction between depressants and the model minerals. Full article

Bio-gels are a class of functional polymeric materials with three-dimensional network structures. Their exceptional biocompatibility, biodegradability, high specific surface area, and tunable physicochemical properties make them highly promising for environmental remediation. This article systematically reviews the classification of bio-gels based on source, cross-linking mechanisms, and functional attributes. It also elaborates on their fundamental properties such as porous structure, high water absorbency, stimuli-responsiveness, and mechanical stability and examines how these properties influence their environmental remediation efficiency. This review comprehensively analyze the mechanisms and efficacy of bio-gels in adsorbing heavy metal ions, removing organic dyes, improving soil water retention, and restoring ecosystems. Special attention is given to the interactions between surface functional groups and contaminants, the role of porous structures in mass transfer, and the ecological effects within soil–plant systems. Additionally, this review explores extended applications of bio-gels in medical tissue engineering, controlled release of drugs and fertilizers, and enhanced oil recovery, highlighting their versatility as multifunctional materials. Finally, based on current progress and challenges, this review outline key future research directions. These include elucidating microscopic interaction mechanisms, developing low-cost renewable feedstocks, designing multi-stimuli-responsive structures, improving long-term stability, and establishing full life-cycle environmental safety assessments. These efforts will help advance the efficient, precise, and sustainable use of bio-gels in environmental remediation, offering innovative solutions to complex environmental problems. Full article

Titanium-containing nanoparticles have emerged as materials of significant technological importance due to their multifunctional properties and excellent performance. With their expanding applications, the amount of TiO₂ nanoparticles (TNPs) being released into the soil environment has increased significantly. This review addresses the gap in current research, which has predominantly focused on the environmental behavior of TNPs in aquatic systems while lacking systematic integration of the synergetic mechanism of adsorption–transformation–ecological effects in soil systems and its guiding value for practical applications. It deeply reveals the interaction mechanisms between TNPs and environmental pollutants. TNPs exhibit outstanding adsorption performance towards environmental pollutants such as heavy metals and organic compounds. Specifically, the maximum adsorption capacities of titanate nanowhiskers for the heavy metal ions Cu(II), Pb(II), and Cr(III) are 143.9 mg·g⁻¹, 384.6 mg·g⁻¹, and 190.8 mg·g⁻¹, respectively. Additionally, 1-hydroxydinaphthoic acid surface-modified nano-TiO₂ exhibits an adsorption rate of up to 98.6% for p-nitrophenol, with an enrichment factor of 50-fold. The transformation process of TNPs after pollutant adsorption profoundly affects their environmental fate, among which pH is a critical controlling factor: when the environmental pH is close to the point of zero charge (pHpzc = 5.88), TNPs exhibit significant aggregation behavior and macroscopic sedimentation. Meanwhile, factors such as soil solution chemistry, dissolved organic matter, and microbial activities collectively regulate the aggregation, aging, and chemical/biological transformation of TNPs. In the soil ecosystem, TNPs can exert both beneficial and detrimental impacts on various soil organisms, including bacteria, plants, nematodes, and earthworms. The beneficial effects include alleviating heavy metal stress, serving as a nano-fertilizer to supply titanium elements, and acting as a nano-pesticide to enhance plants’ antiviral capabilities. However, excessively high concentrations of TiO₂ can stimulate plants, induce oxidative stress damage, and impair plant growth. This review also highlights promising research directions for future studies, including the development of safer-by-design TNPs, strategic surface modifications to enhance functionality and reduce risks, and a deeper understanding of TNP–soil microbiome interactions. These avenues are crucial for guiding the sustainable application of TNPs in soil environments. Full article