Retention Capacity Research Articles

Plant growth stage and melatonin concentration dependency together drive the metal-nutrient dynamics of rice in paddy soil.

Foliar application of melatonin shows promise in alleviating oxidative stress in rice, though its influence on metal-nutrient dynamics remains unclear. This study investigated the optimal dosage, timing, and concentration of melatonin for regulating elemental uptake, maintaining redox homeostasis, and managing nutrient dynamics in rice cultivated in cadmium (Cd) and selenium (Se)-enriched soils. Melatonin (50, 200 µM) was applied at vegetative stages: jointing (J) and tillering (T). At the J stage, melatonin improved biomass and photosynthetic pigments but inadequately regulated metal-nutrient dynamics due to incomplete redox homeostasis. However, applying 200 µM melatonin during the T stage significantly (p < 0.05) enhanced Se and iron (Fe) root uptake by 48% and 11%, respectively, while also improving shoot translocation. Notably, M200 reduced chromium (Cr) translocation to shoots by 82% (p < 0.05), thereby increasing root retention capacity. Additionally, 50 µM melatonin reduced root Cd uptake by 54% and increased its translocation to shoots by 53% (p < 0.05), alleviating root toxicity and enhancing the detoxification response in aerial tissues. Melatonin application reduced oxidative stress markers, increased proline levels, and enhanced antioxidative enzyme activities, with M200 at the T stage showing pronounced effects. This strategy represents a promising technological approach for managing elemental homeostasis in rice cultivation.

In Vitro Drug Release and Ex Vivo Dermal Drug Permeation Studies of Selected Commercial Benzoyl Peroxide Topical Formulations: Correlation Between Human and Porcine Skin Models.

In vitro release testing (IVRT) serves as a crucial tool to assess the quality, physicochemical behavior, and performance of semisolid formulations already available on the market. In vitro skin permeation studies (IVPT) are widely used to evaluate the safety and efficacy profiles of topical drugs, utilizing biological membranes prepared from ex vivo human and porcine skin tissues. This study aimed to develop and validate a discriminative IVRT method to evaluate various marketed topical benzoyl peroxide formulations. Additionally, IVPT was employed to assess skin permeation and retention profiles of these formulations, comparing porcine skin results with those obtained by using ex vivo human skin tissues. Physicochemical differences among the evaluated benzoyl peroxide formulations were identified, with the poloxamer-based formulation exhibiting a higher release rate. IVPT using both porcine and human skin differentiated retention and skin permeation profiles, with the poloxamer-based formulation demonstrating greater skin retention capacity compared to the other formulations evaluated. Similar conclusions on benzoyl peroxide retention and cutaneous permeation were drawn from both porcine and human skin IVPT tests, confirming the correlation between the two models.

Effects of Straw Decomposition on Soil Surface Evaporation Resistance and Evaporation Simulation

As a prominent agricultural country, China has widely implemented returning straw to the field in agricultural production. However, as the decomposition of straw progresses, the physical properties of the soil change, inevitably leading to alterations in the soil surface evaporation model. This study investigated the variations in soil evaporation rate, soil moisture content over 60 days after returning straw to the field, and bare soil through two leaching pond experiments. Through soil moisture retention curves at different degrees of decomposition, this study analyzed the impact of straw decomposition on soil’s water retention capacity. Based on measured data, this study formulated models for the soil surface evaporation resistance of bare soil and varying degrees of straw decomposition. With the comparison and contrast between the models, this study clarified the impact of straw decomposition on soil surface evaporation resistance. The main conclusions are the following: The moisture content of the surface soil decreases exponentially over time and, after 40 days of straw decomposition, the water content of the soil under decomposition is higher than that of bare soil. As the moisture content decreases, the cumulative evaporation from the soil increases linearly. The cumulative evaporation of the decomposed straw soil is lower than that of bare soil, with a relative reduction ranging from 3.08% to 32.2%. The straw decomposition significantly enhances the water retention capacity of the soil in the medium-to-high suction range. The straw decomposition enhances the evaporation resistance of the soil surface, and the greater the degree of decomposition, the more significant the enhancement effect. The research findings not only provide a scientific basis for agricultural water management, but also possess practical implications for guiding farmers to adopt more effective moisture retention measures.

The effects of chitosan oligosaccharides on the structure and shelf-life of whole-millet cakes

The production of high-quality gluten-free whole-millet cakes presents significant challenges to the food industry. This research examined the impact of chitosan oligosaccharides (COS) on the structural properties and shelf life of whole-millet cakes. Fourier transform infrared spectroscopy and X-ray diffraction analyses revealed that hydrogen bonding between COS and millet starch reduced the relative crystallinity of the cakes. Increased concentrations of COS were associated with a reduction in free water migration within the system, thereby enhancing water retention capacity. A suitable concentration of COS contributed to a more continuous protein network structure, preserving the internal integrity of the cakes. At a COS concentration of 0.8 %, minimal changes were observed in color, hardness, springiness, and moisture loss during storage. Furthermore, the incorporation of COS extended the shelf-life of the cakes by 3–6 days. These findings suggest that COS enhances the quality and storage stability of gluten-free food products.

Assessment of runoff generation capacity and total runoff contribution for different landscapes in alpine and permafrost watershed

Alpine vegetation, cold deserts, and glacial landscapes significantly impact runoff generation and convergence in cold and alpine regions. The presence of existing mountain permafrost complicates these impacts further. To better understand the specific regulation of runoff by alpine landscapes, we analyzed the spatiotemporal capacity for runoff generation and the contributions of water from different landscape types within a typical alpine permafrost watershed: the upper reaches of the Shule River (USR) basin in the Qinghai-Tibet Plateau. The analysis was informed by both field observations and simulations using the VIC model, which incorporated a new glacier module. We identified that glaciers, alpine meadows, cold deserts, and barren landscape zones as the four major runoff generation regions, collectively accounting for approximately 95 % of the USR runoff. The runoff depth in each landscape zone was calculated to express its “runoff generation capacity,” with an order of: glacier > cold desert > barren > alpine grassland > alpine meadow > shrub > swamp meadow. The alpine regions above 4000 m in altitude are the primary runoff generation areas, and the “runoff generation capacity” gradually decreases from high to low altitudes in the alpine basin. Due to seasonal variations in rainfall distribution, glacier melting, and permafrost thawing-freezing, the dominant landscape types contributing to runoff varied monthly. The simulated results indicate that permafrost plays an important role in runoff generation. Although permafrost degradation had a slight impact on the annual total runoff generated from each landscape zone (not taking into account of ground ice), seasonal runoff generated in each landscape exhibited significant changes in response to permafrost thawing. After permafrost completely thawed in each landscape zone, generated flood flow decreased, while low flow conversely increased, implying an enhanced water retention capacity of alpine landscapes following permafrost degradation. Additionally, the responses of runoff to permafrost changes varied across different alpine landscapes. These findings enhance our understanding of the mechanisms underlying runoff generation and convergence in cold and alpine watersheds of the Northern Hemisphere.

Deciphering adsorption behaviour and mechanisms of enhanced phosphate removal via optimized cetyltrimethylammonium bromide-modified nanofibrillated cellulose.

To combat the persistent environmental issues resulting from eutrophication, it is necessary to scavenge excess phosphorous levels from aquatic ecosystems. In response, a cationic adsorbent was prepared by modifying agrowaste-derived natural biomacromolecule; nanofibrillated cellulose (NFC) using cetyltrimethylammonium bromide (CTAB) surfactant. Comprehensive characterization through XRD, FTIR, HR-SEM, SEM-EDX, BET and XPS demonstrated that quaternizing NFC significantly improved its surface chemistry by introducing substantial quaternary ammonium groups. This modification imparted positive ζ potential across broad pH range, underscoring a strong affinity for negatively charged phosphate ions. Enhanced roughness and improved spatial dispersion led to nearly threefold increase in phosphate removal efficiency compared to pristine NFC, attributable to a higher number of available active sites. The adsorption process followed pseudo-second-order kinetic and Sips isotherm model, with a maximum adsorption capacity of 21.78 mg P/g, reaching equilibrium within 120 min. Besides, the prepared adsorbent demonstrated pH-dependent adsorption and displayed stable adsorption capacity particularly at weakly acidic or neutral pH conditions. Furthermore, it exhibited excellent retention capacity with only 12.61 % desorption rates over three cycles. Both XPS and FTIR results revealed that electrostatic adsorption (based on Lewis acid-base principle) and hydrogen bonding were primary adsorption mechanism.

THE EFFECT OF SEWAGE EFFLUENCE ON THE PERMEABILITY OF SOIL

Sewage is water-carried wastes, in either solution or suspension that flow away from a community. Soil permeability is the ability of the soil to pass water under saturated conditions. This study addressed a critical environmental concern surrounding the potential impact of sewage discharge on soil permeability with a view to providing insights into the potential threats posed by sewage effluent on soil ecosystems, informing sustainable wastewater management practices and contributing to the broader discourse on environmental protection and resource conservation. This study therefore aimed to investigate the effects of sewage effluence on the permeability of soil. The samples collected for this study were soil, test specimen (laterite) and sewage effluence (collected from excavating up to depth of one meter below the ground surface in Federal polytechnic Offa and the disposal site at Owode market in abattoir, Offa, Kwara State). The lateritic soil samples were evaluated using standard analytical methods for moisture content, particle size analysis, Atterberg limit, liquid limit, plastic limit, plasticity index, compaction test and permeability test. The results of the varying analysis conducted on the lateritic soil showed that the lateritic soil has high water retention capacity, good particle size distribution which are suitable for use in road construction, plasticity index of the soil reduce when mixed with the clean water but increased when mixed with the waste water while the permeability of the soil sample decreased with increase in the percentage of sewage effluent used for the test. The study therefore concluded that permeability of any soil sample depended on the void ratio of the soil since water passed through only the voids present in a soil sample, the effect of pollution on permeability of soil should depend on the effect of the pollution on the void ratio of the sample, permeability of the soil sample was hindered by pollution. The study recommended that the research should be carried out using pollution of higher pollutant strength.

Quantitative determination of cellulose content of peels of selected plants growing in Enugu Urban

Recycling agricultural waste into industrial raw materials can lessen pollution in the environment and encourage entrepreneurship among the increasing number of unemployed life science graduates. This study created cellulose from plantain and cassava peels that had physicochemical characteristics similar to those of cellulose that are made commercially. For 16 hours, 90% ethanol was used to defat the powdered cassava and plantain peels (CPP and PPP, respectively), with sporadic shaking using a mechanical shaker set to 150 rpm. Every defatted PP was dried for seven hours at 800C in a hot air oven. Deproteination was accomplished by soaking in 1mol of NaOH solution at a PH of 11.6 for 24 hours at a ratio of 1.10w/v (100g PP/1000ml). For three hours, the deflated and deproteinated PPP and CPP were immersed in 15% hydrogen peroxide. Hausner's Quotient of CPC and PPC, bulk density, packed density, hydrated density, emulsifying activity, and water and oil retention capabilities were all examined. For CPP and PPP, the peel powders have crude fat concentrations of 3.20% and 2.18%, respectively, and protein contents of 4.50% and 3.85%. The bulk densities of CPC, PPC, and CC are 0.52, 0.55, and 0.21, respectively, while their packed densities are 0.68, 0.73, and 0.28. The CC (1.98) has a lower water retention capacity (WRC) than the CPC (3.09) and PPC (2.96). The ORC of 3.23 for the CC was higher than that of the PPC and CPC (0.11).

Influence of Different Uses and Covers on the Chemical Characteristics of A Quartzarenic Neosol in the Maranhão Savannah

Objective: This study evaluated the effect of three different land uses and soil covers on the chemical characteristics of a QUARTZARENIC NEOSSOLO in the Maranhão Cerrado. The treatments studied were: conventional pasture (PC), open area (AD) and typical cerrado (CT). Theoretical Reference: The study is based on concepts of soil fertility, especially the impact of agricultural management practices, such as liming and fertilisation, on the chemical composition of the soil. The QUARTZARENIC NEOSSOLS, due to their sandy texture and low nutrient and water retention capacity, present limitations for agricultural cultivation, according to studies by Embrapa (2021). Method: Macronutrients (P, S, Ca and Mg), micronutrients (Zn, Mn, Fe and Cu), organic matter (OM) content and base saturation (V%) were analysed. Samples were collected according to the protocol suggested by Embrapa (2015) and were taken from three representative areas of the treatments mentioned. The data was analysed using statistical tests of variance (ANOVA) and paired mean tests (Tukey). Results and Discussion: The results showed that, for most of the chemical parameters analysed, the highest averages were obtained in the conventional pasture area (CP). This is due to the chemical residues from liming and fertilisation applied when the pasture was established and managed. On the other hand, the uncovered area (AD) and the typical cerrado (CT) showed lower concentrations of nutrients and organic matter. The analysis also revealed that the QUARTZARENIC NEOSSOLS in this region, despite their natural limitations, can be productive when well managed. Research Implications: The research highlights the importance of proper soil management, especially liming and fertilisation, to improve fertility and make agricultural production viable on QUARTZARENIC NEOSSOLS. Conventional grazing can be an effective strategy for improving the soil's chemical conditions, although it is also necessary to properly manage bare areas to avoid soil degradation. Originality/Value: This study contributes to the understanding of the effects of different land uses on the chemical properties of QUARTZ NEOSSOLS in the Maranhão Cerrado. The research offers insights into how to improve agricultural productivity and the sustainability of management in areas with natural limitations, highlighting the potential of areas apparently unsuitable for cultivation.

Fluoride Exposure Modulates Skeletal Development and Mineralization in Zebrafish Larvae.

The presence of high levels of fluoride (F) in groundwater is a major issue worldwide. Although F is essential for healthy teeth and bones, excessive exposure can cause fluorosis or F toxicity. This condition primarily affects the hard tissues due to their high F retention capacity. F accumulation alters bone formation and resorption mechanisms interfering with mineral homeostasis and eventually manifests as skeletal fluorosis. Albeit the numerous studies on skeletal fluorosis, the effect of F on developmental osteogenesis is inconclusive. In light of this, we studied the effect of F on osteogenic differentiation, bone development, and mineralization in zebrafish. Zebrafish embryos were subjected to a low (25 ppm NaF), and a moderately high (50 ppm NaF) dose, along with a control (E3 medium alone) until 7 days postfertilization (dpf). The F content in the larvae was quantified to reveal a dose-dependent increase in the exposed groups. Alizarin Red and alkaline phosphatase (ALP) staining suggested enhanced mineralization in the F-treated groups. Quantitative analyses of the ALP activity and hydroxyproline (Hyp) content revealed similar results. Alcian blue staining of pharyngeal cartilages showed that F exposure alters the morphology of the major cartilages, indicating a possible craniofacial defect. Moreover, gene expression analyses of the bone markers associated with osteogenic differentiation, early mineralization, and remodeling (runx2a/b, bmp4, ocn, osx, col1a1, alp, rank, rankl, and opg) showed enhanced expression in the low F group. While the 50 ppm F group showed a decline in osteogenic activity, a considerable increase in the expression of mineralization markers was observed. The expression levels of cartilage markers sox9a and sox9b, remained insignificant, indicating the effect of F toxicity on osteogenesis and mineralization. Also, F exposure interferes with bone metabolism through altered osteogenic differentiation, development, and mineralization in zebrafish larvae.

Understanding perfume deposition mechanisms on different textile substrates in a realistic laundering process

AbstractThe laundering process is an essential routine for maintaining the cleanliness and freshness of textiles. Achieving an efficient deposition and retention of fragrances on different fabric types remains a complex challenge. This study provides a novel comparison of the impact on perfume deposition of different fabric types across wash cycle stages and wash conditions. The critical role of perfume redeposition during rinsing is examined, where micelles entrapped in the textile matrix break due to surfactant concentrations dropping below the critical micelle concentration (CMC), resulting in the release and subsequent redeposition on fabrics of perfume raw materials (PRMs) contained in the micelles. Our findings reveal that adsorption kinetics are faster on cotton compared with polyester. Cotton, due to its amphoteric nature, exhibits greater interaction with water molecules during rinsing, leading to more significant PRM loss. Conversely, polyester demonstrates a higher PRM retention capacity, which can be attributed to its hydrophobic nature. Surprisingly, however, we find that redeposition during the rinse steps of hydrophobic PRMs is more pronounced on cotton than polyester, which may be due to their respective water retention capacities and consequent effect on the micelle breaking mechanism.

Relationship Between Urbanization–Induced Land Use Changes and Flood Risk: Case Study in Chiang Mai, Thailand

Urban flooding has long been a critical issue, particularly in rapidly urbanizing regions of developing countries, where land use changes—especially the conversion of rice paddies into urban areas—have significantly increased flood risks. This study investigated the impact of urbanization on flood risk taking Chiang Mai, Thailand, as a case study. Based on historical flood data, the study identified and analyzed frequent flood–prone areas in Chiang Mai during the period from 1990 to 2018. By integrating the Rainfall–Runoff–Inundation (RRI) model simulation results and the remote sensing data, the research quantified dynamics in flood risk, exposure, and vulnerability across these frequent flood–prone areas. The findings demonstrated that the conversion of high–exposure paddy fields into urban areas markedly elevated area flood risks, primarily due to the reduction in water retention capacity and the inheritance of the high–exposure characteristics of paddy fields. This study highlighted the importance of integrating sustainable urban planning and land management strategies in rapidly urbanizing regions. Furthermore, this study examined the feasibility of adopting flood characteristics quantification in frequent flood–prone areas as a systematic approach to analyze the dynamic interplay between flood risks and urbanization in developing countries.

Spatial Distribution Characteristics and Relationships of Salt-Based Ions and Nutrients in Old Protected Vegetable Fields

To achieve a scientific and objective evaluation of soil acidification, secondary salinization, and nutrient imbalance in old protected vegetable fields (OPVs) with over 30 years of cultivation history, a soil surface breeding vigorous moss was investigated. Here, quantitative laboratory analysis and mathematical statistics were employed to explore the spatial distribution of soil salinity and nutrients, as well as their relationships. The results revealed that OPVs exhibited slightly acidified values. The measured anions and cations in the soil salt composition constituted approximately 77% of the total ions. Among which, Ca2+ was the dominant cation, while SO42− and NO3− were predominant anions. The total water-soluble salt (TDS) content of the surface soil reached 4.52 g kg−1, exceeding the Chinese Saline Soils standard (1.0 g kg−1) by 350%. In the OPVs, nitrate nitrogen was significantly higher than ammonium nitrogen, and available phosphorus and available potassium were generally abundant. Despite exhibited various soil health concerns, a field visit survey presented consistently high and stable yields in OPVs. We hypothesize that this seemingly contradictory finding may be attributable to several factors, including the abundance of divalent cations (Ca2+ and Mg2+), the soil fertility and water retention capacity of unsaturated salt-based suitable soil, as well as good soil aggregate structure. These factors had the potential to reduce the stresses on the soil. This study provided a foundational understanding of the nutrient and salinity status of soils in OPVs, offering valuable data and theoretical groundwork for future research endeavors.

The effect of the load of bushes with shoots on the stress resistance of grapes of the varieties Vladimir, Dmitry, Kurchansky

Due to the currently observed global and local climate changes, there is an imbalance in the biological cycles of plants, a change in their resistance to biotic and abiotic stressors. The level of realization of the potential of economic productivity of grape varieties in the Krasnodar Territory is low and amounts to 60%. At the heart of its increase is the optimization of the placement of grape plantations, taking into account varietal characteristics and variety-oriented, zone-oriented technologies of grape cultivation. Varietal agrotechnology, which provides for the establishment of an optimal load of grape bushes with shoots, plays an important role in regulating the growth of the grape bush and its individual parts, the formation of plant resistance to stressors and the quality of viticulture products. Due to the more frequent manifestation of stressful weather conditions during the growing season of grapes, namely, insufficient soil moisture in combination with high temperature and low humidity, an urgent area of research is the study of stress resistance indicators under different loads of bushes with shoots. The purpose of the research is to study the effect of the load of bushes with shoots on the stress resistance of grape varieties of domestic selection Vladimir, Dmitry, Kurchansky. Indicators characterizing the stress resistance of plants, such as electrolyte yield, hydration, water deficiency and loss of water by leaves (water retention capacity), have been studied. A variety-specific reaction of grape plants to changes in the load of bushes with shoots under stressful conditions (insufficient precipitation and high air temperature) has been established. Increasing the load in Dmitry and Kurchansky grape varieties improves stress resistance indicators, such as tissue hydration, water deficiency and water retention capacity. The Vladimir variety had the best performance with a minimum and average load of bushes with shoots.

Fluorinated Macrocycle for Adsorptive Separation and Chromatographic Separation of Toluene and Methylcyclohexane.

Achieving the adsorptive separation and chromatographic separation of industrially the important chemicals toluene and methylcyclohexane using the same material is a highly desirable goal. We have successfully accomplished this using a fluorinated macrocycle tetrafluoroterphen[3]arene (4FTP3), which was synthesized and used for gas chromatographic separation in our previous work. The macrocycle 4FTP3 permitted the adsorptive separation of toluene from a toluene/methylcyclohexane mixture (1:1, v/v) with a purity of 99.3% in a single adsorption cycle. Additionally, the use of 4FTP3 as a gas chromatographic stationary phase permitted the high-resolution separation of a toluene/methylcyclohexane mixture, with a retention capacity decreasing in the order of: toluene>methylcyclohexane. Single-crystal structural analysis revealed that the C-H···F interactions between 4FTP3 and toluene resulted in an enhanced binding affinity, association enthalpy, and longer retention time for toluene. This macrocycle is of particular interest for use as a separation material due to its simultaneous adsorptive separation and gas chromatographic separation of toluene/methylcyclohexane. The present fluorinated macrocycle may therefore have roles to play in both analytical science and the chemical industry.

Effects of meteorological factors on the retention of particulate matter in lawn grass blades

Plant leaves can reduce the concentration of atmospheric particulate matter (PM) by absorbing it in the air, and this mitigates the deleterious human health effects of PM. However, the ability of plant leaves to retain dust is limited and varies continually due to various meteorological factors such as rainfall, extreme wind speed, and PM10 concentrations. Here, we measured the ability of seven types of turfgrass with leaves similar in macromorphology but varying in micromorphology to retain dust particles of different sizes; we also analyzed the effects of various meteorological factors, such as rainfall, maximum wind speed, and PM10 concentration, on the ability of leaves to retain particles of different sizes. There were significant differences in the ability of the seven types of turfgrass to retain particles of different sizes; the dust retention capacity of Zoysia sinensis was the strongest(2.04 g·m-2), and that of Festuca elata was the weakest(1.39 g·m-2). The elution rates of PM&amp;gt;10 after rainfall of 3 mm and 4 mm were significantly higher than those of PM2.5-10 and PM2.5; the elution rates of PM&amp;gt;10, PM2.5-10, and PM2.5 increased as the amount of rainfall increased. When the amount of dust on leaves is low, wind promotes increases in leaf PM retention. When the blade retains a certain amount of dust, the maximum wind speed is greater than 9.1 m·s-1, which leads to a decrease in the dust retention of lawn grass blades. The concentrations of PM10 and PM2.5 were positively correlated with the retention of particles of different particle sizes. Therefore, evaluations of the dust retention ability of plant leaves require consideration of the effects of local rainfall, maximum wind speed, PM10 concentration, and other factors.

A Computational Study of Dielectric Properties of Coconut Shell Powder and Coconut Shell-Activated Carbon and Organic Soil

This study investigates the dielectric properties of artificial soil mixtures created using Coconut Shell Powder (CSP), Coconut Shell-Activated Carbon (CSAC), and Organic Soil. CSP, known for its lightweight and excellent water retention capacity, was combined with CSAC, renowned for its superior adsorption properties and enhanced conductivity. Organic Soil, rich in nutrients, served as a base material for improving soil texture and supporting plant growth. Three mixtures were prepared in ratios of 50% CSP, 30% CSAC, and 20% Organic Soil; 60% CSP, 20% CSAC, and 20% Organic Soil; and 40% CSP, 40% CSAC, and 20% Organic Soil. The dielectric constant, dielectric loss factor, loss tangent, conductivity, and skin depth were analyzed using Lichtenecker's logarithmic mixture model and MATLAB simulations. Results revealed that the mixture with 50% CSP, 30% CSAC, and 20% Organic Soil exhibited the highest dielectric constant and skin depth, indicating its potential for soil moisture sensing, energy storage, and electromagnetic shielding applications. This innovative approach highlights the benefits of CSP and CSAC in artificial soil development for sustainable agriculture and urban greening.

New opportunities for biologically and chemically mediated adsorption and precipitation of phosphorus from wastewater.

Biologically mediated adsorption and precipitation of phosphorus (P) from waste streams can restrict environmental P discharges. Here, we appraise progress in this field over the past decade. The research discipline has grown considerably in recent years. Industry 'wastes', including steel slags, continue to show promise as adsorbents with exceptionally high P retention capacities (>500mgPg-1). Hydrotalcite, a nanomineral, offers prospects as a P removal technology with imbedded climate change mitigation capacity. Biomineral struvite formation, driven by microbial processes, offers an exciting P removal and recovery approach that can be applied to diverse wastewater types due to its feedstock-independent mechanisms, emerging immobilisation techniques and adaptability to mixed cultures. All of these factors facilitate efficient nutrient recycling and scalable application to the wastewater industry. Adsorbed and precipitated P can be applied to cropland to offset dependence on conventional fertiliser inputs. Therefore, in addition to water treatment, these biologically mediated processes also offer opportunities to support food production. Moreover, as many of the input materials covered in this review are industry byproducts and common organic materials, the removal of P from waste streams by adsorption and precipitation offers strong circularity potential that aligns with the UN's Sustainable Development Goals. We call for future work to focus on long-term full-scale trials involving community, government and industry partners.

Optimizing nature-based solutions for urban flood risk mitigation: A multi-objective genetic algorithm approach in Gdańsk, Poland.

Nature-based Solutions (NbS) have emerged as a sustainable approach to managing flood risks by enhancing natural water retention and reducing surface runoff in urban areas. As climate change and rapid urbanization exacerbate flood hazards, optimizing the spatial deployment of NbS is crucial for improving urban resilience and mitigating flood impacts. This study presents a comprehensive optimization framework for the spatial allocation of fourteen different NbS types aimed at mitigating urban flood risks in Gdańsk, Poland. Leveraging a genetic algorithm alongside the Urban Flood Risk Mitigation (UFRM) model of the Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) software suite, we identified areas of the city most vulnerable to pluvial flooding and optimized NbS placement to maximize water retention and reduce runoff. The optimization process balanced multiple objectives, including minimizing implementation costs and maximizing water retention capacity, ensuring that the solutions are both economically feasible and environmentally effective. Three distinct scenarios were proposed: a cost-effective solution, a high-retention solution, and a balanced solution, offering urban planners a range of strategies to address flood risks based on their specific priorities and constraints. Results demonstrated considerable variations in water retention effectiveness across different NbS configurations, with denser urban regions showing the most significant improvements from targeted interventions. The optimized placement of NbS resulted in estimated total water retention improvement of approximately 15.5% for the best solution considered. These findings provide valuable insights for integrating NbS into urban flood management strategies, enhancing citywide resilience, sustainability, and long-term flood mitigation.

A Review on Sustainable Slow-Release N, P, K Fertilizer Hydrogels for Smart Agriculture.

The agricultural sector of any country plays a pivotal role in its economy. Irrigation and the provision of appropriate nutrient levels in soil are essential for optimizing plant growth and enhancing crop productivity. To support the increasing need for food due to the growing population worldwide, synthetic fertilizers have been widely used in the agricultural sector. These fertilizers could readily dissolve in the irrigation water or soil moisture, causing excessive release of the nutrients that plants cannot uptake from the root zone. The excess nutrients in the soil further harm the environment via surface run-off, leaching, and volatilization. Thus, materials with high water absorption and retention capacity, and precise control over the prolonged fertilizer release offer a potential solution to address these issues. To meet these requirements, the development of slow-release fertilizer hydrogels (SRFHs) represents a promising approach. SRFHs serve as natural agrochemicals to enhance crop growth and yield through controlled and self-sustained delivery of water and nutrients. This review provides a comprehensive study on the recent advancements in SRFHs, including their preparation methods, properties, slow-release behavior, and applications in smart agriculture. The response of soil microbial diversity to slow-release fertilizers is briefly discussed, and the future potential of SRFHs is highlighted herein.