Removal of Erythromycin from Water by Ibuprofen-Driven Pre-Organized Divinyl Sulfone Cross-Linked Dextrin

Water recycling and reuse are cornerstones of water management, which can be compromised by the presence of pollutants. Among these, pharmaceuticals can overcome standard water treatments and require sophisticated approaches to remove them. Sorption is an economically viable alternative limited by the need for sorbents with a sorption coefficient (Kd) higher than 500 L/kg. The cross-linking of dextrin (Dx) with divinyl sulfone (DVS) in the presence of 1 mmol or 5 mmol of ibuprofen (IBU) yields the insoluble polymers pDx1 and pDx5 with improved affinity for IBU and high selectivity towards erythromycin (ERY) and ERY Kd higher than 4 × 103 L/kg, when tested against a cocktail of six drugs. Characterization of the polymers shows that both pDx1 and pDx5 have similar properties, fast sorption kinetics, and ERY Kd of 13.3 × 103 for pDx1 and 6.4 × 103 for pDx5, representing 26.6 and 12.0 times the 500 L/kg threshold. The fact that new affinities and improvements in Kd can be achieved by cross-linking Dx in the presence of other molecules that promote pre-organization expands the applications of DVS cross-linked polysaccharides as sustainable, scalable, and environmentally friendly sorbents with a potential application in wastewater treatment plants (WTPs).

Solar desalination system for fresh water production performance estimation in net-zero energy consumption building: A comparative study on various machine learning models

This study employs diverse machine learning models, including classic artificial neural network (ANN), hybrid ANN models, and the imperialist competitive algorithm and emotional artificial neural network (EANN), to predict crucial parameters such as fresh water production and vapor temperatures. Evaluation metrics reveal the integrated ANN-ICA model outperforms the classic ANN, achieving a remarkable 20% reduction in mean squared error (MSE). The emotional artificial neural network (EANN) demonstrates superior accuracy, attaining an impressive 99% coefficient of determination (R2) in predicting freshwater production and vapor temperatures. The comprehensive comparative analysis extends to environmental assessments, displaying the solar desalination system's compatibility with renewable energy sources. Results highlight the potential for the proposed system to conserve water resources and reduce environmental impact, with a substantial decrease in total dissolved solids (TDS) from over 6,000 ppm to below 50 ppm. The findings underscore the efficacy of machine learning models in optimizing solar-driven desalination systems, providing valuable insights into their capabilities for addressing water scarcity challenges and contributing to the global shift toward sustainable and environmentally friendly water production methods.

Stakeholder engagement does not guarantee impact: A co-productionist perspective on model-based drought research

Stakeholder engagement has become a watchword for environmental scientists to assert the societal relevance of their projects to funding agencies. In water research based on computer simulation modelling, stakeholder engagement has attracted interest as a means to overcome low uptake of new tools for water management. An increasingly accepted view is that more and better stakeholder involvement in research projects will lead to increased adoption of the modelling tools created by scientists in water management. However, we cast doubt on this view by drawing attention to how the freedom of stakeholder organizations to adopt new scientific modelling tools in their regular practices is circumscribed by the societal context. We use a modified concept of co-production in an analysis of a case of scientific research on drought in the UK to show how relationships between actors in the drought governance space influence the uptake of scientific modelling tools. The analysis suggests an explanation of why stakeholder engagement with one scientific project led to one output (data) getting adopted by stakeholders while another output (modelling tools) attracted no discernible interest. Our main objective is to improve the understanding of the limitations to stakeholder engagement as a means of increasing societal uptake of scientific research outputs.

Physiological Responses of a Grapefruit Orchard to Irrigation with Desalinated Seawater

Desalinated seawater (DSW) has emerged as a promising solution for irrigation in regions facing water scarcity. However, adopting DSW may impact the existing cultivation model, given the presence of potentially harmful elements, among other factors. A three-year experiment was carried out to assess the short-term effects of four irrigation waters-freshwater (FW), DSW, a mix 1:1 of FW and DSW (MW), and DSW with low boron (B) concentration (DSW-B)-on a 'Rio Red' grapefruit orchard. These irrigation waters exhibited varying levels of phytotoxic elements, some potentially harmful to citrus trees. Sodium (Na+) and chloride (Cl-) concentrations exceeded citrus thresholds in all treatments, except in DSW-B, whilst B exceeded toxicity levels in DSW and MW treatments. Leaf concentrations of Cl- and Na+ remained low in all treatments, whereas B approached toxic levels only in DSW and MW-irrigated trees. The rapid growth of the trees, preventing excessive accumulation through a dilution effect, protected the plants from significant impacts on nutrition and physiology, such as gas exchange and chlorophyll levels, due to phytotoxic elements accumulation. Minor reductions in photosynthesis in DSW-irrigated trees were attributed to high B in leaves, since Cl- and Na+ remained below toxic levels. The accelerated tree growth effectively prevented the substantial accumulation of phytotoxic elements, thereby limiting adverse effects on tree development and yield. When the maturation of trees reaches maximal growth, the potential accumulation of phytotoxic elements is expected to increase, potentially influencing tree behavior differently. Further study until the trees reach maturity is imperative for comprehensive understanding of the long-term effects of desalinated seawater irrigation.

The development of variable system-based internet of things for the solar greenhouse and its application in lettuce

The east-west ridge orientation has recently become an important agronomic method to improve mechanization in solar greenhouses. However, these ridge orientation changes shape differences between different ridges in crop water consumption, and there is a lack of research on the regulation and adaptation of water consumption. Therefore, this study introduces a variable irrigation decision-making method based on the Internet of Things management and control system for an east-west ridge orientation. To replenish water on demand, this study seting the variable irrigation decision-making (VRI) methods and traditional average irrigation decision-making (URI) methods in the system, and lettuce cultivation experiments were conducted to verify the effectiveness of the model and system. The results show that the difference of accumulated photosynthetically active radiation is the most significant between different ridges of the east-west ridge orientation, and the coefficient of variation is 43.77 %, which can be used as an activating factor for VRI methods. The irrigation water consumption, yield, water-use efficiencies, and irrigation water utilization of lettuce at different levels of irrigation were 307.12 L/m2, 5854.07 kg·ha-1, 1391.47 kg·ha-1·mm-1, and 7.63 kg·cm-3, respectively. Compared with the URI methods, the VRI method saved 10.02 % of water, increased yield by 9 %, and enhanced water use efficiency and irrigation water use efficiency by 12 % and 21.32 %, respectively. This study provides a new approach for improving crop production efficiency under an east-west ridge orientation.

Measuring and Manipulating the Rhine River Branches: Interactions of Theory and Embodied Understanding in Eighteenth Century River Hydraulics

Eighteenth century river hydraulics used both theory and measurement to address problems of flood safety, navigation and defense related to the rivers. In the late eighteenth century the Dutch overseer of the rivers, Christiaan Brunings, integrated hydraulic theory and meteorological practices, which enabled him to design a unique instrument for measuring river flow. The question is whether the unprecedented detail of measurements fits the putative empirical stance in the eighteenth century. The interactions between theory, instrument, measurement, and other knowledge practices are here assessed using experiences in similar measurement practices. I argue that Brunings had theoretical and embodied understanding of hydrodynamics, as he knew how to design an instrument for flow measurement of sufficient accuracy for his purpose in the sociopolitical context of river management.

Application of Artificial Intelligence in the Management of Drinking Water: A Narrative Review

Waterborne illnesses are a significant concern worldwide. The management of water resources can be facilitated by artificial intelligence (AI) with the help of data analytics, regression models, and algorithms. Achieving the Sustainable Development Goals (SDGs) of the 2030 Agenda for Sustainable Development of the United Nations depends on understanding, communicating, and measuring the value of water and incorporating it into decision-making. Various barriers are used from the source to the consumer to prevent microbiological contamination of drinking water sources or reduce contamination to levels safe for human health. Infrastructure development and capacity-building policies should be integrated with guidelines on applying AI to problems relating to water to ensure good development outcomes. Communities can live healthily with such technology if they can provide clean, economical, and sustainable water to the ecosystem as a whole. Quick and accurate identification of waterborne pathogens in drinking and recreational water sources is essential for treating and controlling the spread of water-related diseases, especially in resource-constrained situations. To ensure successful development outcomes, policies on infrastructure development and capacity building should be combined with those on applying AI to water-related problems. The primary focus of this study is the use of AI in managing drinking water and preventing waterborne illness.

Microbiological hazards associated with the use of water in the post-harvest handling and processing operations of fresh and frozen fruits, vegetables and herbs (ffFVHs). Part 1 (outbreak data analysis, literature review and stakeholder questionnaire)

The contamination of water used in post-harvest handling and processing operations of fresh and frozen fruit, vegetables and herbs (ffFVHs) is a global concern. The most relevant microbial hazards associated with this water are: Listeria monocytogenes, Salmonella spp., human pathogenic Escherichia coli and enteric viruses, which have been linked to multiple outbreaks associated with ffFVHs in the European Union (EU). Contamination (i.e. the accumulation of microbiological hazards) of the process water during post-harvest handling and processing operations is affected by several factors including: the type and contamination of the FVHs being processed, duration of the operation and transfer of microorganisms from the product to the water and vice versa, etc. For food business operators (FBOp), it is important to maintain the microbiological quality of the process water to assure the safety of ffFVHs. Good manufacturing practices (GMP) and good hygienic practices (GHP) related to a water management plan and the implementation of a water management system are critical to maintain the microbiological quality of the process water. Identified hygienic practices include technical maintenance of infrastructure, training of staff and cooling of post-harvest process water. Intervention strategies (e.g. use of water disinfection treatments and water replenishment) have been suggested to maintain the microbiological quality of process water. Chlorine-based disinfectants and peroxyacetic acid have been reported as common water disinfection treatments. However, given current practices in the EU, evidence of their efficacy under industrial conditions is only available for chlorine-based disinfectants. The use of water disinfection treatments must be undertaken following an appropriate water management strategy including validation, operational monitoring and verification. During operational monitoring, real-time information on process parameters related to the process and product, as well as the water and water disinfection treatment(s) are necessary. More specific guidance for FBOp on the validation, operational monitoring and verification is needed.

Effects of the COVID-19 Pandemic on Legionella Water Management Program Performance across a United States Lodging Organization

Legionella, the bacterium that causes Legionnaires' disease, can grow and spread in building water systems and devices. The COVID-19 pandemic impacted building water systems through reductions in water usage. Legionella growth risk factors can be mitigated through control measures, such as flushing, to address stagnation, as part of a water management program (WMP). A national lodging organization (NLO) provided WMP data, including Legionella environmental testing results for periods before and during the pandemic. The statistical analysis revealed an increased risk of water samples testing positive for Legionella during the pandemic, with the greatest increase in risk observed at the building's cold-water entry test point. Sample positivity did not vary by season, highlighting the importance of year-round Legionella control activities. The NLO's flushing requirements may have prevented an increased risk of Legionella growth during the pandemic. However, additional control measures may be needed for some facilities that experience Legionella detections. This analysis provides needed evidence for the use of flushing to mitigate the impacts of building water stagnation, as well as the value of routine Legionella testing for WMP validation. Furthermore, this report reinforces the idea that WMPs remain the optimal tool to reduce the risk of Legionella growth and spread in building water systems.

The Covid-19 Pandemic: Limited Water Access and the Precarity of Women Fishers at Lake Kariba, Zimbabwe

Man-made reservoirs are constructed to meet certain purposes and Lake Kariba, Zimbabwe, was designed for hydroelectric power generation. However, it has developed other multiple uses, and the growth of fisheries on the lake has had a significant impact on the livelihoods of local communities. The declaration of Covid-19 as a pandemic in Zimbabwe in March 2020 was quickly followed by the imposition of national lockdowns with varying levels of severity up to the present day. This was done to curtail the spread of the disease, meanwhile enhancing the nation's capacity in terms of acquiring testing kits, constructing more admission and quarantine centres as well as educating the people about ways to keep safe. In response to the calls by the government to monitor the movement of people and compliance of the lockdown rules, the Zimbabwe National Parks and Wildlife Management Authority (ZNPWMA), the governing body of the Lake Kariba fisheries, imposed rules that have significantly impacted the fishing communities at Lake Kariba. Both gillnet fishers and rod and line fishers have been impacted, but our focus here is on women rod and line fishers. Using the precarious livelihoods conceptual frameworks, we show how the changes in water management during the Covid-19 pandemic lockdowns has generated high levels of precariousness on the livelihoods of women at Kariba. We define precariousness as the condition of uncertainties brought to the women fishers by changes in water restrictions. The precarity of women was induced by several factors. For instance, the women fishers reported that restrictions to accessing fish in areas with high catches impacted them. They are also now obliged to pay exorbitant fishing fees in a way to discourage them to fish; they were frequently chased away from the Lake by ZNPWMA officers; they had limited amount of time to fish due to curfews; and failure to comply results in heavy fines imposed on them among other challenges. We show how these challenges interact with the current Zimbabwe socio-economic crisis to worsen the precariousness and vulnerability of women fishers at Lake Kariba. Data presented in this manuscript are based on participant observation and interviews with women fishers at Lake Kariba.

Removal of the Water Pollutant Ciprofloxacin Using Biodegradable Sorbent Polymers Obtained from Polysaccharides

Water use has been increasing globally by 1% per year, and recycling and re-use are critical issues compromised by the presence of pollutants. In this context, the design of novel materials and/or procedures for the large scale-removal of pollutants must be economically and environmentally feasible in order to be considered as part of the solution by emerging economies. We demonstrate that the cross-linking of biodegradable polysaccharides such as starch, dextrin, or dextrin and β-cyclodextrin with divinyl sulfone is an innovative strategy for synthesizing insoluble and eco-friendly sorbent polymers, including pSt, pDx and pCD-Dx. The evaluation of these polymers' ability to remove ciprofloxacin (CIP), a prime example of antibiotic pollution, revealed that pSt, with a Kd of 1469 L/kg and a removal rate higher than 92%, is a favorable material. Its sorption is pH-dependent and enhanced at a mildly alkaline pH, allowing for the desorption (i.e., cleaning) and reuse of pSt through an environmentally friendly treatment with 20 mM AcONa pH 4.6. The facts that pSt (i) shows a high affinity for CIP even at high NaCl concentrations, (ii) can be obtained from affordable starting materials, and (iii) is synthesized and regenerated through organic, solvent-free procedures make pSt a novel sustainable material for inland water and seawater remediation, especially in less developed countries, due to its simplicity and low cost.

The influence of the Covid-19 pandemic and climate change on water use and supply: experience of Istanbul, Türkiye

The coronavirus (Covid-19) pandemic has affected not only populations around the world but also the environment and natural resources. Lockdowns and restricted lifestyles have had wide-ranging impacts on the environment (e.g., air quality in cities). Although hygiene and disinfection procedures and precautions are effective ways to protect people from Covid-19, they have significant consequences for water usage and resources especially given the increasing impacts of climate change on rainfall patterns, water use and resources. Climate change and public health issues may compound one another, and so we used a drivers, pressures, state, impact, response framework (not previously used to examine the actual and potential impacts of Covid-19 and climate change on water consumption and resources) to scope the main factors that may interact to affect water use and resources (in the form of reservoirs) using evidence from Istanbul, Türkiye, with some discussion of the comparative situation elsewhere. We modified initial views on the framework to account for the regional, city and community level experiences. We note that water consumption in Istanbul has been increasing over the last two decades (except in times of very low rainfall/drought); that there were increases in water consumption in the early stages of the Covid-19 pandemic; and, despite some increase in rainfall, water levels in reservoirs appeared to decrease during lockdowns (for a range of reasons). Through a new simple way of visualising the data, we also noted that a low resource capacity might be recurring every 6 or 7 years in Istanbul (a similar finding to Thames Reservoir in London). We made no attempt in this paper to quantify the relative contribution that climate change, population growth, etc., are making to water consumption and reservoir levels as we focused on looking at those social, environmental and economic factors that appear to play a role in potential water stress and on developing a drivers, pressures, state, impact, response framework for policy and adaptive management options for Istanbul and other large complex conurbations. If there are periodic water resource issues and temperatures rise as expected in climate projections with an accompanying increase in the duration of hot spells, the subsequent additional stress on water systems might make managing future public health emergencies, such as a pandemic, even more difficult.

Two-Stage Microporous Layers with Gradient Pore Size Structure for Improving the Performance of Proton Exchange Membrane Fuel Cells

In this paper, we report the preparation of a gas diffusion layer (GDL) with different gradient pore size structures. The pore structure of microporous layers (MPL) was controlled by the amount of pore-making agent sodium bicarbonate (NaHCO₃). We investigated the effects of the two-stage MPL and the different pore size structures in the two-stage MPL on the performance of proton exchange membrane fuel cells (PEMFC). The conductivity and water contact angle tests showed that the GDL had outstanding conductivity and good hydrophobicity. The results of the pore size distribution test indicated that introducing a pore-making agent altered the pore size distribution of the GDL and increased the capillary pressure difference within the GDL. Specifically, there was an increase in pore size within the 7-20 μm and 20-50 μm ranges, which improved the stability of water and gas transmission within the fuel cell. The maximum power density of the GDL03 was increased by 37.1% at 40% humidity, 38.9% at 60% humidity, and 36.5% at 100% humidity when compared to the commercial GDL29BC in a hydrogen-air environment. The design of gradient MPL ensured that the pore size between carbon paper and MPL changed from an initially abrupt state to a smooth transition state, which significantly improved the water and gas management capabilities of PEMFC.

Water Management Capacity of Metal Foam Flow Field for PEMFC under Flooding Situation

Porous metal foam with complex opening geometry has been used as a flow field to enhance the distribution of reactant gas and the removal of water in polymer electrolyte membrane fuel cells. In this study, the water management capacity of a metal foam flow field is experimentally investigated by polarization curve tests and electrochemical impedance spectroscopy measurements. Additionally, the dynamic behavior of water at the cathode and anode under various flooding situations is examined. It is found that obvious flooding phenomena are observed after water addition both into the anode and cathode, which are alleviated during a constant-potential test at 0.6 V. Greater abilities of anti-flooding and mass transfer and higher current densities are found as the same amount of water is added at the anode. No diffusion loop is depicted in the impedance plots although a 58.3% flow volume is occupied by water. The maximum current density of 1.0 A cm^-2 and the lowest R_ct around 17 mΩ cm² are obtained at the optimum state after 40 and 50 min of operation as 2.0 and 2.5 g of water are added, respectively. The porous metal pores store a certain amount of water to humidify the membrane and achieve an internal "self-humidification" function.

Pore-Scale Modeling of Liquid Water Transport in Compressed Gas Diffusion Layer of Proton Exchange Membrane Fuel Cells Considering Fiber Anisotropy

Water management of the gas diffusion layer (GDL) is crucial to the performance of proton exchange membrane fuel cells (PEMFCs). Appropriate water management ensures efficient transport of reactive gases and maintains wetting of the proton exchange membrane to enhance proton conduction. In this paper, a two-dimensional pseudo-potential multiphase lattice Boltzmann model is developed to study liquid water transport within the GDL. Liquid water transport from the GDL to the gas channel is the focus, and the effect of fiber anisotropy and compression on water management is evaluated. The results show that the fiber distribution approximately perpendicular to the rib reduces liquid water saturation within the GDL. Compression significantly changes the microstructure of the GDL under the ribs, which facilitates the formation of liquid water transport pathways under the gas channel, and the increase in the compression ratio leads to a decrease in liquid water saturation. The performed microstructure analysis and the pore-scale two-phase behavior simulation study comprise a promising technique for optimizing liquid water transport within the GDL.

Quantification of PEFC Catalyst Layer Saturation via In Silico, Ex Situ, and In Situ Small-Angle X-ray Scattering

The complex nature of liquid water saturation of polymer electrolyte fuel cell (PEFC) catalyst layers (CLs) greatly affects the device performance. To investigate this problem, we present a method to quantify the presence of liquid water in a PEFC CL using small-angle X-ray scattering (SAXS). This method leverages the differences in electron densities between the solid catalyst matrix and the liquid water filled pores of the CL under both dry and wet conditions. This approach is validated using ex situ wetting experiments, which aid the study of the transient saturation of a CL in a flow cell configuration in situ. The azimuthally integrated scattering data are fitted using 3D morphology models of the CL under dry conditions. Different wetting scenarios are realized in silico, and the corresponding SAXS data are numerically simulated by a direct 3D Fourier transformation. The simulated SAXS profiles of the different wetting scenarios are used to interpret the measured SAXS data which allows the derivation of the most probable wetting mechanism within a flow cell electrode.

Trunk Water Potential Measured with Microtensiometers for Managing Water Stress in "Gala" Apple Trees

The weather variations around the world are already having a profound impact on agricultural production. This impacts apple production and the quality of the product. Through agricultural precision, growers attempt to optimize both yield and fruit size and quality. Two experiments were conducted using field-grown "Gala" apple trees in Geneva, NY, USA, in 2021 and 2022. Mature apple trees (Malus × domestica Borkh. cv. Ultima "Gala") grafted onto G.11 rootstock planted in 2015 were used for the experiment. Our goal was to establish a relationship between stem water potential (Ψ_trunk), which was continuously measured using microtensiometers, and the growth rate of apple fruits, measured continuously using dendrometers throughout the growing season. The second objective was to develop thresholds for Ψ_trunk to determine when to irrigate apple trees. The economic impacts of different irrigation regimes were evaluated. Three different water regimes were compared (full irrigation, rainfed and rain exclusion to induce water stress). Trees subjected the rain-exclusion treatment were not irrigated during the whole season, except in the spring (April and May; 126 mm in 2021 and 100 mm in 2022); that is, these trees did not receive water during June, July, August and half of September. Trees subjected to the rainfed treatment received only rainwater (515 mm in 2021 and 382 mm in 2022). The fully irrigated trees received rain but were also irrigated by drip irrigation (515 mm in 2021 and 565 mm in 2022). Moreover, all trees received the same amount of water out of season in autumn and winter (245 mm in 2021 and 283 mm in 2022). The microtensiometer sensors detected differences in Ψ_trunk among our treatments over the entire growing season. In both years, experimental trees with the same trunk cross-section area (TCSA) were selected (23-25 cm^-2 TCSA), and crop load was adjusted to 7 fruits·cm^-2 TCSA in 2021 and 8.5 fruits·cm^-2 TCSA in 2022. However, the irrigated trees showed the highest fruit growth rates and final fruit weight (157 g and 70 mm), followed by the rainfed only treatment (132 g and 66 mm), while the rain-exclusion treatment had the lowest fruit growth rate and final fruit size (107 g and 61 mm). The hourly fruit shrinking and swelling rate (mm·h^-1) measured with dendrometers and the hourly Ψ_trunk (bar) measured with microtensiometers were correlated. We developed a logistic model to correlate Ψ_trunk and fruit growth rate (g·h^-1), which suggested a critical value of -9.7 bars for Ψ_trunk, above which there were no negative effects on fruit growth rate due to water stress in the relatively humid conditions of New York State. A support vector machine model and a multiple regression model were developed to predict daytime hourly Ψ_trunk with radiation and VPD as input variables. Yield and fruit size were converted to crop value, which showed that managing water stress with irrigation during dry periods improved crop value in the humid climate of New York State.

Water Management Impacts on Chromium Behavior and Uptake by Rice in Paddy Soil with High Geological Background Values

Chromium (Cr) is an expression toxic metal and is seriously released into the soil environment due to its extensive use and mining. Basalt is an important Cr reservoir in the terrestrial environment. Cr in paddy soil can be enriched by chemical weathering. Therefore, basalt-derived paddy soils contain extremely high concentrations of Cr and can enter the human body through the food chain. However, the water management conditions' effect on the transformation of Cr in basalt-derived paddy soil with high geological background values was less recognized. In this study, a pot experiment was conducted to investigate the effects of different water management treatments on the migration and transformation of Cr in a soil-rice system at different rice growth stages. Two water management treatments of continuous flooding (CF) and alternative wet and dry (AWD) and four different rice growth stages were set up. The results showed that AWD treatment significantly reduced the biomass of rice and promoted the absorption of Cr in rice plants. During the four growth periods, the root, stem and leaf of rice increased from 11.24-16.11 mg kg^-1, 0.66-1.56 mg kg^-1 and 0.48-2.29 mg kg^-1 to 12.43-22.60 mg kg^-1, 0.98-3.31 mg kg^-1 and 0.58-2.86 mg kg^-1, respectively. The Cr concentration in roots, stems and leaves of AWD treatment was 40%, 89% and 25% higher than CF treatment in the filling stage, respectively. The AWD treatment also facilitated the potential bioactive fractions conversion to the bioavailable fraction, compared with the CF treatment. In addition, the enrichment of iron-reducing bacteria and sulfate-reducing bacteria with AWD treatment also provided electron iron for the mobilization of Cr, thus affecting the migration and transformation of Cr in the soil. We speculated that the reason for this phenomenon may be the bioavailability of Cr was affected by the biogeochemical cycle of iron under the influence of alternating redox. This indicates that AWD treatment may bring certain environmental risks in contaminated paddy soil with high geological background, and it is necessary to be aware of this risk when using water-saving irrigation to plant rice.

Increasing stability of a native freshwater fish assemblage following flow rehabilitation

Stream restorations are increasingly critical for managing and recovering freshwater biodiversity in human-dominated landscapes. However, few studies have quantified how rehabilitative actions promulgate through aquatic communities over decades. Here, a long-term dataset is analyzed for fish assemblage change, incorporating data pre- and post-restoration periods, and testing the extent to which native assemblage stability increased over time. In the late 1950s, a large capacity dam was installed on Putah Creek (Solano County, CA, USA) which altered the natural flow regime, channel structure, geomorphic processes, and overall ecological function. Notably, downstream flows were reduced (especially during summer months) resulting in an aquatic assemblage dominated by warmwater nonnative species, while endemic native species subsisted at low levels as subordinates. A court-mediated Accord was ratified in 2000 providing a more natural flow regime, specifically for native and anadromous fishes in the stream. Richness of nonnative species decreased at every site following the Accord, while richness of native species increased or stayed constant. At the three most upstream sites, native species richness increased over time and ultimately exceeded nonnative richness. Native assemblage recovery was strongest upriver, closer to flow releases and habitat restoration activities, and decreased longitudinally downstream. Rank-abundance curves through time revealed that while species evenness was low throughout the study, dominance shifted from nonnative to native species in the upstream sites coincident with rehabilitation efforts. Mean rank shifts decreased following flow rehabilitation; thus the assemblage became increasingly stable over time following flow rehabilitation. Putah Creek's rehabilitation may represent a model for others interested in improving endemic freshwater communities in degraded ecosystems. This article is protected by copyright. All rights reserved.

Dry direct-seeded rice has higher energy and carbon production efficiencies

BACKGROUND

Water and energy shortages and food security challenges associated with global warming are essential issues affecting human survival and development. Rice is one of the world's top three staple food crops. In this study, the energy footprint (EF), carbon footprint (CF), energy production efficiency (EPE), carbon production efficiency (CPE), and economic benefit (EB) of dry direct-seeded rice (DSR), wet direct-seeded rice (WSR), and transplanted rice (TPR) were integrated and assessed.

RESULTS

The yield of WSR and TPR was 9.64% and 13.76% higher than that of DSR, respectively. However, DSR has less irrigation and less intensive field tillage, therefore its energy input, and CF were 37.47%, 44.29% and 29.35%, 34.77% lower than those of WSR and TPR, respectively, and the EPE and CPE were obviously improved, and the EB was not lower than that of WSR and TPR. Current rice production relies heavily on non-renewable energy inputs such as nitrogen fertilizer, diesel, and machinery. Therefore, the key to improving EPE, CPE, and EB in rice production while reducing CF was to improve water use efficiency and decrease the intensity of paddy tillage.

CONCLUSION

The DSR has higher social, economic, and ecological benefits and can be the preferred rice planting method for rice production areas. This article is protected by copyright. All rights reserved.

Silver Nanoparticles for Waste Water Management

Rapidly increasing industrialisation has human needs, but the consequences have added to the environmental harm. The pollution caused by several industries, including the dye industries, generates a large volume of wastewater containing dyes and hazardous chemicals that drains industrial effluents. The growing demand for readily available water, as well as the problem of polluted organic waste in reservoirs and streams, is a critical challenge for proper and sustainable development. Remediation has resulted in the need for an appropriate alternative to clear up the implications. Nanotechnology is an efficient and effective path to improve wastewater treatment/remediation. The effective surface properties and chemical activity of nanoparticles give them a better chance to remove or degrade the dye material from wastewater treatment. AgNPs (silver nanoparticles) are an efficient nanoparticle for the treatment of dye effluent that have been explored in many studies. The antimicrobial activity of AgNPs against several pathogens is well-recognised in the health and agriculture sectors. This review article summarises the applications of nanosilver-based particles in the dye removal/degradation process, effective water management strategies, and the field of agriculture.

Transcriptional Expression of Nitrogen Metabolism Genes and Primary Metabolic Variations in Rice Affected by Different Water Status

The era of climate change strongly requires higher efficiency of energies, such as light, water, nutrients, etc., during crop production. Rice is the world's greatest water-consuming plant, and, thus, water-saving practices such as alternative wetting and drying (AWD) are widely recommended worldwide. However the AWD still has concerns such as lower tillering, shallow rooting, and an unexpected water deficit. The AWD is a possibility to not only save water consumption but also utilize various nitrogen forms from the soil. The current study tried to investigate the transcriptional expression of genes in relation to the acquisition-transportation-assimilation process of nitrogen using qRT-PCR at the tillering and heading stages and to profile tissue-specific primary metabolites. We employed two water supply systems, continuous flooding (CF) and alternative wetting and drying (AWD), during rice growth (seeding to heading). The AWD system is effective at acquiring soil nitrate; however, nitrogen assimilation was predominant in the root during the shift from the vegetative to the reproductive stage. In addition, as a result of the greater amino acids in the shoot, the AWD was likely to rearrange amino acid pools to produce proteins in accordance with phase transition. Accordingly, it is suggested that the AWD 1) actively acquired nitrate from soil and 2) resulted in an abundance of amino acid pools, which are considered a rearrangement under limited N availability. Based on the current study, further steps are necessary to evaluate form-dependent N metabolism and root development under the AWD condition and a possible practice in the rice production system.

Low-Cost Internet-of-Things Water-Quality Monitoring System for Rural Areas

Water is a vital source for life and natural environments. This is the reason why water sources should be constantly monitored in order to detect any pollutants that might jeopardize the quality of water. This paper presents a low-cost internet-of-things system that is capable of measuring and reporting the quality of different water sources. It comprises the following components: Arduino UNO board, Bluetooth module BT04, temperature sensor DS18B20, pH sensor-SEN0161, TDS sensor-SEN0244, turbidity sensor-SKU SEN0189. The system will be controlled and managed from a mobile application, which will monitor the actual status of water sources. We propose to monitor and evaluate the quality of water from five different water sources in a rural settlement. The results show that most of the water sources we have monitored are proper for consumption, with a single exception where the TDS values are not within proper limits, as they outperform the maximum accepted value of 500 ppm.

Synergistic Effects of Water Management and Silicon Foliar Spraying on the Uptake and Transport Efficiency of Cadmium in Rice (Oryza sativa L.)

To study the synergistic effects of water management and silicon (Si) foliar spraying on the uptake and transport of cadmium (Cd) in rice, we designed four treatments: conventional intermittent flooding + no Si foliar spraying (CK), continuous flooding throughout the growth stage + no Si foliar spraying (W), conventional intermittent flooding + Si foliar spraying (Si) and continuous flooding throughout the growth stage + Si foliar spraying (WSi). The results show that WSi treatment reduced the uptake and translocation of Cd by rice and significantly reduced the brown rice Cd content, with no effect on rice yield. Compared with CK, the Si treatment increased the net photosynthetic rate (Pn), stomatal conductance (Gs) and transpiration rate (Tr) of rice by 6.5-9.4%, 10.0-16.6% and 2.1-16.8%, respectively. The W treatment decreased these parameters by 20.5-27.9%, 8.6-26.8% and 13.3-23.3%, respectively, and the WSi treatment decreased them by 13.1-21.2%, 3.7-22.3% and 2.2-13.7%, respectively. The superoxide dismutase (SOD) and peroxidase (POD) activity decreased by 6.7-20.6% and 6.5-9.5%, respectively, following the W treatment. Following the Si treatment, SOD and POD activity increased by 10.2-41.1% and 9.3-25.1%, respectively, and following the WSi treatment, they increased by 6.5-18.1% and 2.6-22.4%, respectively. Si foliar spraying ameliorated the detrimental effects of continuous flooding throughout the growth stage on photosynthesis and antioxidant enzyme activity. We conclude that synergistic continuous flooding throughout the growth stage, combined with Si foliar spraying, can significantly block Cd uptake and translocation and is therefore an effective means of reducing the accumulation of Cd in brown rice.

Multicompartment Depletion Factors for Water Consumption on a Global Scale

Balancing human communities' and ecosystems' need for freshwater is one of the major challenges of the 21st century as population growth and improved living conditions put increasing pressure on freshwater resources. While frameworks to assess the environmental impacts of freshwater consumption have been proposed at the regional scale, an operational method to evaluate the consequences of consumption on different compartments of the water system and account for their interdependence is missing at the global scale. Here, we develop depletion factors that simultaneously quantify the effects of water consumption on streamflow, groundwater storage, soil moisture, and evapotranspiration globally. We estimate freshwater availability and water consumption using the output of a global-scale surface water-groundwater model for the period 1960-2000. The resulting depletion factors are provided for 8,664 river basins, representing 93% of the landmass with significant water consumption, i.e., excluding Greenland, Antarctica, deserts, and permanently frozen areas. Our findings show that water consumption leads to the largest water loss in rivers, followed by aquifers and soil, while simultaneously increasing evapotranspiration. Depletion factors vary regionally with ranges of up to four orders of magnitude depending on the annual consumption level, the type of water used, aridity, and water transfers between compartments. Our depletion factors provide valuable insights into the intertwined effects of surface and groundwater consumption on several hydrological variables over a specified period. The developed depletion factors can be integrated into sustainability assessment tools to quantify the ecological impacts of water consumption and help guide sustainable water management strategies, while accounting for the performance limitations of the underlying model.

Hydrochemistry and stable isotopes revealed focused and diffuse recharge processes in the Sonora River basin, Mexico

A hydro-geochemical characterization was conducted in the northern part of the Sonora River basin, covering an area of 9400 km². Equipotential lines indicated that groundwater circulation coincided with the surface water flow direction. Based on the groundwater temperature measured (on average ∼21 °C), only one spring exhibited thermalism (51 °C). Electrical conductivity (160-1750 μS/cm), chloride and nitrate concentrations (>10 and >45 mg/L) imply highly ionized water and anthropogenic pollution. In the river network, δ¹⁸O values revealed a clear modern meteoric origin. Focused recharge occurred mainly from the riverbeds during the rainy season. During the dry season, diffuse recharge was characterized by complex return flows from irrigation, urban, agricultural, mining, and livestock. Drilled wells (>50 m) exhibited a strong meteoric origin from higher elevations during the rainy season with minimal hydrochemical anomalies. Our results contribute to the knowledge of mountain-front and mountain-block recharge processes in a semi-arid and human-altered landscape in northern Mexico, historically characterized by limited hydrogeological data.

Evaluating the Phytoremediation Potential of Eichhornia crassipes for the Removal of Cr and Li from Synthetic Polluted Water

Heavy metals like chromium (Cr) are hazardous pollutants for aquatic life in water bodies. Similarly, lithium (Li) is also an emerging contaminant in soil and water which later is taken up by plants. The aim of the present study is to evaluate the removal rate of Cr and Li by Eichhornia crassipes. The rate of the removal of Cr and Li by roots, stems, and leaves of E. crassipes were evaluated. The translocation factor (TF) and bioaccumulation factor (BAF) were also estimated. Roots of E. crassipes accumulated higher concentrations of Cr and Li as compared to the stems and leaves. BAF for Cr and Li showed that E. crassipes effectively accumulated the Cr and Li in the roots as compared to the stems and leaves. Statistical analysis showed that E. crassipes removed significant concentrations of Cr and Li (p ≤ 0.05). Thus, this study recommends that Cr and Li can be effectively removed by E. crassipes. High concentrations of Cr and Li could also be removed by E. crassipes. This technology could be used for the cleanup of the environment because it is eco-friendly and cost-effective.

Deep Learning to Reveal the Distribution and Diffusion of Water Molecules in Fuel Cell Catalyst Layers

Water management in the catalyst layers (CLs) of proton-exchange membrane fuel cells is crucial for its commercialization and popularization. However, the high experimental or computational cost in obtaining water distribution and diffusion remains a bottleneck in the existing experimental methods and simulation algorithms, and further mechanistic exploration at the nanoscale is necessary. Herein, we integrate, for the first time, molecular dynamics simulation with our customized analysis framework based on a multiattribute point cloud dataset and an advanced deep learning network. This was achieved through our workflow that generates simulated transport data of water molecules in the CLs as the training and test dataset. Deep learning framework models the multibody solid-liquid system of CLs on a molecular scale and completes the mapping from the Pt/C substrate structure and Nafion aggregates to the density distribution and diffusion coefficient of water molecules. The prediction results are comprehensively analyzed and error evaluated, which reveals the highly anisotropic interaction landscape between 50,000 pairs of interacting nanoparticles and explains the structure and water transport property relationship in the hydrated Nafion film on the molecular scale. Compared to the conventional methods, the proposed deep learning framework shows computational cost efficiency, accuracy, and good visual display. Further, it has a generality potential to model macro- and microscopic mass transport in different components of fuel cells. Our framework is expected to make real-time predictions of the distribution and diffusion of water molecules in CLs as well as establish statistical significance in the structural optimization and design of CLs and other components of fuel cells.

Application of "Behind the Barriers" Model at Neighbourhood Scale to Improve Water Management under Multi-Risks Scenarios: A Case Study in Lyon, France

In modern urban areas, water management highly depends on the socio-ecological urban water cycle (UWC) that heavily relies on water infrastructures. However, increasing water-related hazards, natural and/or human-based, makes it difficult to balance water resources in the socio-ecological UWC. In the last decade, urban infrastructure resilience has rapidly become a popular topic in disaster risk management and inspired many studies and operational approaches. Among these theories and methods, the "Behind the Barriers" model (BB model), developed by Barroca and Serre in 2013, is considered a theory that allows effective and comprehensive analysis of urban infrastructure resilience through cognitive, functional, correlative, and organisational dimensions. Moreover, this analysis can be a reference to develop actions that improve infrastructure resilience under critical scenarios. Therefore, this study aims to study resilience design actions based on the BB model to achieve socio-ecological water balance and assess the performance of these actions. The study focuses on water management on a neighbourhood scale, which is considered the essential urban unit to study and improve the resilience of critical infrastructures, such as water services. The Part-Dieu neighbourhood in Lyon, France is selected as a case study, and it highlights the need to develop indicators to assess the performance of implemented actions in a structural and global resilience framework, to understand urban systems as complex and dynamic systems to provide decision support, and to strengthen crisis prevention and management perspectives in a dynamic approach.

Nutrient dynamics in water and soil under conventional rice cultivation in the Vietnamese Mekong Delta

Background The evaluation of nutrient variability plays a crucial role in accessing soil potentials and practical intervention responses in rice production systems. Synthetic fertilizer applications and cultivation practices are considered key factors affecting nutrient dynamics and availability. Here, we assessed the nutrient dynamics in surface, subsurface water and soil under local water management and conventional rice cultivation practices in the Vietnamese Mekong Delta. Methods We implemented a field experiment (200 m 2) in the 2018 wet season and the 2019 dry season in a triple rice-cropping field. Eight samples of surface water, subsurface water (30-45 cm), and topsoil (0-20 cm) were collected and analysed during the rice-growing seasons. Results The results showed that N-NH 4 +, P-PO 4 3- and total P peaks were achieved after fertilizing. Irrespective of seasons, the nutrient content in surface water was always greater than that of subsurface water ( P < 0.001), with the exception of N-NO 3 -, which was insignificant ( P > 0.05). When comparing the wet and dry seasons, nutrient concentrations exhibited minor differences ( P > 0.05). Under conventional rice cultivation, the effects of synthetic fertilizer topdressing on the total N, soil organic matter (SOM), and total P were negligible in the soil. Higher rates of N fertilizer application did not significantly increase soil N-NH 4 +, total N, yet larger P fertilizer amounts substantially enhanced soil total P ( P < 0.001). Conclusions Under conventional rice cultivation, N-NH 4 +, P-PO 4 3- and total P losses mainly occur through runoff rather than leaching. While N-NO 3 - loss is similar in surface water and subsurface water. Notably, nutrient content in soil was high; whilst SOM was seen to be low-to-medium between seasons. Future work should consider the nutrient balance and dynamic simulation in the lowland soil of the Vietnamese Mekong Delta's paddy fields.

Six Decades of Hindsight Into Yesa Reservoir (Central Spanish Pyrenees): River Flow Dwindles as Vegetation Cover Increases and Mediterranean Atmospheric Dynamics Take Control

River discharge has experienced diverse changes in the last decades due to modification of hydrological patterns, anthropogenic intervention, re-vegetation or annual and interannual climatic and atmospheric fluctuations. Assessing the recent changes in river discharge and understanding the main drivers of these changes is thus extremely important from theoretical and applied points of view. More specifically, here we want to draw attention toward the impacts of streamflow changes on reservoir storage and operation. We describe the hydrological dynamics of the Yesa reservoir draining catchment, located in the central Spanish Pyrenees, and characterize the reservoir operation modes over the last 60 years (1956-2020). We analyze concurrent climatic (precipitation, air temperature, drought index), atmospheric mechanisms, land cover (Normalized Different Vegetation Index) and discharge (inlet and outlet of Yesa reservoir) time-series. By using the wavelet transform methodology, we detect historical breakpoints in the hydrological dynamics at different time-scales. Distinctive periods are thus identified. More regular seasonal flows characterized the catchment's dynamics during the first decades of the study period, while the last decades were characterized by a high inter-annual variability. These changes are primarily attributed to the natural re-vegetation process that the catchment experienced. Furthermore, we related changes in atmospheric circulation with a decline of the long-term discharge temporal features. This research contributes to the understanding of long-term river discharge changes and helps to improve the reservoir management practices.

The impact of farm practices and wild carriers on white spot disease in marine shrimp in Rayong Province, Thailand

Background and Aim

White spot disease (WSD) is a highly lethal and contagious viral disease in marine shrimp caused by the white spot syndrome virus (WSSV). White spot disease impacts the worldwide crustacean aquaculture sector, including Thailand. This study aimed to investigate the effect of farm management practices and wild carriers on WSD occurrence in grow-out marine shrimp farms in Rayong Province, Thailand.

Materials and Methods

A longitudinal study was conducted using a structured questionnaire from June 2018 to June 2020. A total of 186 questionnaires for 186 ponds were collected from 15 shrimp farms. Univariate and multivariable analyses using generalized estimating equations were used to determine the risk factors associated with WSD. In addition, possible carrier samples (wild shrimp and wild crabs) were collected inside and outside farms to test for the presence of WSSV.

Results

Direct discharge of treated wastewater into farm ponds was statistically significant in the final model (p < 0.01), with an odd ratio (OR) factor of 0.097 (95% confidence interval [CI] of OR = 0.007-0.242). Pooled sampling for WSSV in wild shrimp and crabs showed that 48 out of 936 (5.13%) samples tested positive for WSD using nested polymerase chain reaction. The samples from banana shrimp, jinga shrimp, banded snapping shrimp, dwarf prawn, whiteleg shrimp, green tidal crabs, and mangrove crabs tested positive.

Conclusion

Based on the findings of this study, we infer that the environment plays an important role in the spread of this disease. The results of this study will provide insights into the effective planning of disease control.

Teaching Nature and Architecture: Student-Led Account of Biomimicry Innovations in the Tropics

The built environment has a huge carbon footprint, and decarbonizing it is essential in driving our sustainability efforts. We take the approach of biomimicry by working with Master of Architecture students from Taylor's University in Malaysia. The students partake in a 14-week Nature and Architecture design module at the university where they develop biomimicry solutions for the built environment with a focus on sustainability. The students undergo a three-step process of scoping the design problem in the tropical climate and urban context, researching the biological literature, abstracting design ideas, and finally, developing prototypes. The module presents an opportunity for students to study nature and immerse in experiential learning in the megadiverse geographies of Malaysia and wider tropical southeast Asia. This paper describes the student works developed in various module runs from 2017 to 2022 under the supervision of the authors. Selected student projects were analyzed thematically, curated, and classified by frequently occurring themes. Finally, their design implications and challenges faced are presented. We found the following five themes to be most commonly chosen by the students-thermoregulation, structure making, water management, daylighting and ventilation, and transport and mobility. Lastly, we also conducted postgraduation student surveys on their learnings from the module. Through our synthesis, we discuss how student works can bridge the gap of applying biomimicry into practice and the limitations thereof in mainstreaming the practice in the built environment of tropical southeast Asia.

Inaccuracies of the ISO 11731 Method for Environmental Validation of Legionella in Building Water Systems: Opportunities to Improve Sensitivity and Detect Viable but Non-Culturable Legionella

Current environmental diagnostics for the detection of Legionella fail to detect viable but non-culturable Legionella, have sensitivity limitations and are time-consuming (10-14 days to results). The objective of this study was to compare Legionella detection results between the standard ISO 11731 and an innovative Legionella detection method that utilizes a hybrid methodology of traditional microbiology and molecular detection. In this study, four hundred and seventy-six (476) potable building water samples were analyzed with ISO 11731 and the novel method in parallel. Of the 476 total samples that were tested, a discrepancy of 21% was observed when comparing the ISO 11731 method to the novel method. Separating the samples based on hazard control methods yielded a 15.4% discrepancy for chlorinated systems (n = 284) and a 29% discrepancy for monochloraminated systems (n = 192). The data presented here conclusively show inaccuracies in environmental validation for building water systems based on results returned by the standard ISO 11731 method. This is especially evident in systems primarily disinfected with monochloramines. Overall, these data highlight the need for new and innovative methods to overcome the inaccuracies of the traditional ISO 11731 spread plates to prevent disease and injury caused by Legionella.

Gas Diffusion Layer for Proton Exchange Membrane Fuel Cells: A Review

Proton exchange membrane fuel cells (PEMFCs) are an attractive type of fuel cell that have received successful commercialization, benefitted from its unique advantages (including an all solid-state structure, a low operating temperature and low environmental impact). In general, the structure of PEMFCs can be regarded as a sequential stacking of functional layers, among which the gas diffusion layer (GDL) plays an important role in connecting bipolar plates and catalyst layers both physically and electrically, offering a route for gas diffusion and drainage and providing mechanical support to the membrane electrode assemblies. The GDL commonly contains two layers; one is a thick and rigid macroporous substrate (MPS) and the other is a thin microporous layer (MPL), both with special functions. This work provides a brief review on the GDL to explain its structure and functions, summarize recent progress and outline future perspectives.

Grain and Leaf Anthocyanin Concentration Varies among Purple Rice Varieties and Growing Condition in Aerated and Flooded Soil

Anthocyanins are a group of pigments responsible for the red-blue color in plant parts, and have potential for health benefits and pharmaceutical ingredients. To evaluate whether anthocyanin concentrations in five purple rice varieties could be varied by water condition, plants were grown in waterlogged and aerobic (well-drained) soil. Grain anthocyanin concentration and grain yield were measured at maturity, while leaf anthocyanin concentrations were measured at booting and flowering stages. Four varieties grown under the waterlogged condition had 2.0−5.5 times higher grain anthocyanin than in the aerobic condition. There was a positive relationship between grain and leaf anthocyanin at booting in the waterlogged condition (r = 0.90, p < 0.05), while grain and leaf anthocyanin were positively correlated at flowering in both the waterlogged (r = 0.88, p < 0.05) and aerobic (r = 0.97, p < 0.01) conditions. The results suggest that water management should be adopted as a practical agronomic tool for improving the anthocyanin concentration of purple rice for specialist markets, but the specific responses between rice varieties to water management should be carefully considered.

Application of social identity models of collective action to facilitate participation in groundwater aquifer storage and recovery management

Aquifer storage and recovery (ASR) is considered as an innovative method and an alternative one for sustainable management of water resources that has, in recent years, attracted the attention of experts and thinkers. Implementation of this method would entail the participation and collective action of various stakeholders. In this process, farmers are considered as the most important stakeholders; and limited studies have been conducted on their intentions to participate in collective actions of ASR management. In this regard, the investigation of farmers' intention to participate in ASR and its determinants, using social identity models of collective action, was selected as the main purpose of the present study. For this purpose, using a cross-sectional survey, 330 Iranian farmers were interviewed. In this study, the ability of the dual-pathway model of collective action (DPMCA) and the encapsulation model of social identity in collective action (EMSICA) was evaluated and compared to explain farmers' intentions towards participation in ASR management. The results revealed that the both models had good predictive powers. However, DPMCA was a stronger framework than EMSICA for facilitating farmers' collective behaviors in the field of participation in ASR management. This is one of the most important results of the present research that might be used by various users including decision makers, managers, and practitioners of water resources management in Iran and generally the world. Finally, the creation of a "we thinking system" or social identity in the field of ASR management was highlighted as one of the most important take-home messages.

Ultrasonic Guided Waves for Liquid Water Localization in Fuel Cells: An Ex Situ Proof of Principle

Water management is a key issue in the design and operation of proton exchange membrane fuel cells (PEMFCs). For an efficient and stable operation, the accumulation of liquid water inside the flow channels has to be prevented. Existing measurement methods for localizing water are limited in terms of the integration and application of measurements in operating PEMFC stacks. In this study, we present a measurement method for the localization of liquid water based on ultrasonic guided waves. Using a sparse sensing array of four piezoelectric wafer active sensors (PWAS), the measurement requires only minor changes in the PEMFC cell design. The measurement method is demonstrated with ex situ measurements for water drop localization on a single bipolar plate. The wave propagation of the guided waves and their interaction with water drops on different positions of the bipolar plate are investigated. The complex geometry of the bipolar plate leads to complex guided wave responses. Thus, physical modeling of the wave propagation and tomographic methods are not suitable for the localization of the water drops. Using machine learning methods, it is demonstrated that the position of a water drop can be obtained from the guided wave responses despite the complex geometry of the bipolar plate. Our results show standard deviations of 4.2 mm and 3.3 mm in the x and y coordinates, respectively. The measurement method shows high potential for in situ measurements in PEMFC stacks as well as for other applications that require deposit localization on geometrically complex waveguides.

Nitrogen optimization coupled with alternate wetting and drying practice enhances rhizospheric nitrifier and denitrifier abundance and rice productivity

Optimizing nitrogen (N) fertilization without sacrificing grain yield is a major concern of rice production system because most of the applied N has been depleted from the soil and creating environmental consequences. Hence, limited information is available about nutrient management (NM) performance at a specific site under alternate wetting and drying (AWD) irrigation compared to conventional permanent flooding (PF). We aimed to inquire about the performance of NM practices compared to the farmer's fertilizer practice (FFP) under PF and AWD on rhizospheric nitrifier and denitrifier abundance, rice yield, plant growth, and photosynthetic parameters. Two improved NM practices; nutrient management by pig manure (NMPM); 40% chemical N replaced by pig manure (organic N), and nutrient management by organic slow-release fertilizer (NMSR); 40% chemical N replaced by organic slow-release N were compared. The results showed an increased total grain yield (16.06%) during AWD compared to PF. Compared to conventional FFP, NMPM, and NMSR significantly increased the yields by 53.84 and 29.67%, respectively, during AWD. Meanwhile, PF prompted a yield increase of 45.07 and 28.75% for NMPM and NMSR, respectively, (p < 0.05) compared to FFP. Besides, a significant correlation was observed between grain yield and nitrogen content during AWD (R ² = 0.58, p < 0.01), but no significant correlation was observed during PF. The NMPM contributed to photosynthetic attributes and the relative chlorophyll content under both watering events. Moreover, relatively higher abundances of ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) were observed during AWD, and the highest value was found after the late panicle stage. Our results suggest that the AWD-NMPM model is the best option to stimulate nitrifier and denitrifier gene abundance and promote rice production.

[Effects of Water Management on the Transformation of Iron Oxide Forms in Paddy Soils and Its Coupling with Changes in Cadmium Activity]

The transformation of iron oxide forms in the process of soil water management in paddy fields has an important impact on soil cadmium (Cd) activity and accumulation in rice. The test soil for this experiment was purple paddy soil in southwest China contaminated with exogenously added Cd. Through indoor cultivation experiments, the effects of water management (continuous flooding, CW; alternating wet and dry, DW) combined with iron oxide application (goethite, G-Fe; iron powder, Fe) on the pH, redox state (Eh, pe+pH), iron oxide form conversion, and Cd bioavailability changes in Cd-contaminated soil were studied. Meanwhile, the coupling relationship between the transformation of iron oxide form and the evolution of soil Cd activity driven by water management were also analyzed. The results showed that DTPA-Cd content was decreased by 17.7%-39.2% after 93 days of flooding, indicating that CW could significantly reduce soil Cd bioavailability. CW combined with Fe or G-Fe application significantly enhanced the passivating effect on soil Cd. Among them, the DTPA-Cd content of G-Fe application was reduced by 24.3% compared with that of the CK after 14 d of flooding; thus, G-Fe was effective in short-term passivation. The reduction in DTPA-Cd content of Fe application was 39.2% after 93 d of flooding, so Fe was able to passivate soil Cd continuously. It was also found that the application of iron oxides under alternating wet and dry conditions had no passivating effect on soil Cd. Furthermore, based on correlation analysis, the formation of amorphous iron (Fe_o) (P<0.01) was verified as the main reason for the change in Cd bioavailability of Cd in the soil:firstly, the soil pH gradually declined to 7.4, and the soil was kept at reduction conditions under CW, which promoted the morphology transformation from the crystalline state (Fe_c) to Fe_o. This transformation subsequently pushed the Cd transformation from the exchangeable state to the iron-manganese combined state and thus resulted in the significant decrease in Cd bioavailability. Meanwhile, the content and proportion of Fe_o were also significantly increased by the application of CW combined with Fe or G-Fe, thus further enhancing its Cd passivating effect on the soil. This research provides a scientific basis for the optimal water management and the application of iron-containing passivation agent in the safe use of Cd-contaminated paddy soils.

Role of ascomycete and basidiomycete fungi in meeting established and emerging sustainability opportunities: a review

Fungal biomass is the future's feedstock. Non-septate Ascomycetes and septate Basidiomycetes, famously known as mushrooms, are sources of fungal biomass. Fungal biomass, which on averagely comprises about 34% protein and 45% carbohydrate, can be cultivated in bioreactors to produce affordable, safe, nontoxic, and consistent biomass quality. Fungal-based technologies are seen as attractive, safer alternatives, either substituting or complementing the existing standard technology. Water and wastewater treatment, food and feed, green technology, innovative designs in buildings, enzyme technology, potential health benefits, and wealth production are the key sectors that successfully reported high-efficiency performances of fungal applications. This paper reviews the latest technical know-how, methods, and performance of fungal adaptation in those sectors. Excellent performance was reported indicating high potential for fungi utilization, particularly in the sectors, yet to be utilized and improved on the existing fungal-based applications. The expansion of fungal biomass in the industrial-scale application for the sustainability of earth and human well-being is in line with the United Nations' Sustainable Development Goals.

Water and Nitrogen Management at the Booting Stage Affects Yield, Grain Quality, Nutrient Uptake, and Use Efficiency of Fragrant Rice Under the Agro-Climatic Conditions of South China

The present study was conducted to assess the effects of water and nitrogen applications at the booting stage on yield, grain quality, and nutrient use efficiencies in fragrant rice in the early (March-July) and late (July-November) seasons of 2013. The experiment was comprised of two fragrant rice cultivars, i.e., Nongxiang 18 and Basmati; three nitrogen levels, i.e., 0 kg N ha^-1 (N0), 30 kg N ha^-1 (N1), and 60 kg N ha^-1 (N2); and three water levels, i.e., 2-4 cm water layer well-watered (W0), water with a soil water potential of -15 ± 5 kPa (W1), and water with a soil water potential of -25 ± 5 kPa (W2), which were randomized in a split-split plot design. Results showed that Basmati produced a higher grain yield than Nongxiang 18 (16.20 and 9.61% in the early and late season, respectively), whereas the W1 exhibited the maximum grain yield and harvest index. The moderate application of nitrogen (N1) at the booting stage resulted in higher grain yield, nevertheless, cultivar, water, and nitrogen revealed different trends for some of the grain quality attributes, i.e., brown rice rate, milled rice rate, head milled rice rate, protein content, and amylose content as well as nutrient uptake and use efficiencies in the double rice production system. Basmati had a higher nitrogen harvest index (NHI; 18.28-20.23%) and P harvest index (PHI; 3.95-12.42%) but lower physiological P use efficiency for biomass (PPUEB; 7.66-23.66%) and physiological K use efficiency for biomass (PKUEB; 2.53-7.10%) than Nongxiang 18 in both seasons. Furthermore, the grain number per panicle, biomass yield, grain P uptake, and the whole plant P uptake were significantly related to the grain yield of fragrant rice. In both seasons, the interaction of water and nitrogen (W × N) had a significant effect on panicle number, grain quality attributes, and N, P uptake of straw, as well as the physiological N, P use efficiency for grain and the physiological N, K use efficiency for biomass. Overall, results suggest that moderate nitrogen and irrigation input at the booting stage could be feasible to improve the productivity and quality of the double rice production system with improved nutrient use efficiency under the agro-climatic conditions of South China.

Stone Wool Substrate Cover Incision Impacts on the Root-Zone Water Content, Temperature, and Yield of Tomato Cultures

Standardized cultivation systems are crucial for establishing reproducible agronomic techniques. Especially stone wool-based cultivation is governed by standardized specifications and provides a controllable root-zone environment. However, the effects of stone wool cover incision on root-zone variability have rarely been studied. Therefore, in this study, we focused on the effect of the stone wool cover incision method on environmental variations and their subsequent effects on tomato plant productivity. Stone wool slab plastic covers represent a core component of this substrate system that can potentially affect the performance of water control techniques. We designed a cover incision method to create four different levels of drainage performances that were tested by cultivating tomato plants (Solanum lycopersicum "Dafnis"). The water content, root-zone temperature, and dissolved oxygen were measured and analyzed relative to the tomato yield. We found that the incision level with the lowest drainage performance showed a lower air-root zone temperature correlation slope than those of slabs with favorable drainage conditions. Furthermore, these slabs had low dissolved oxygen levels (3.2 mg/L); nevertheless, the tomatoes grown in the slabs with incision level showing the lowest drainage performance had greater fruit yield (6,748 g/plant) than those in the slabs with favorable drainage conditions (6,160 g/plant). Furthermore, the normalized yield separation timing between treatments coincided with the hotter air temperature (27°C average) periods. We noted that manipulating the cover incision process consequently entailed variations in the correlation slope between the air temperature and root-zone temperature in the substrate. Our results reveal another trade-off relationship in the conventional perspective on the drainage performance effects and provide insights into further optimization of crop production and water use in the stone wool-based system.

Natural and anthropogenic controls on lake water-level decline and evaporation-to-inflow ratio in the conterminous United States

Lake water levels are integral to lake function, but hydrologic changes from land and water management may alter lake fluctuations beyond natural ranges. We constructed a conceptual model of multifaceted drivers of lake water-levels and evaporation-to-inflow ratio (Evap:Inflow). Using a structural equation modeling framework, we tested our model on 1) a national subset of lakes in the conterminous United States with minimal water management to describe natural drivers of lake hydrology and 2) five ecoregional subsets of lakes to explore regional variation in water management effects. Our model fit the national and ecoregional datasets and explained up to 47% of variation in Evap:Inflow, 38% of vertical water-level decline, and 79% of horizontal water-level decline (littoral exposure). For lakes with minimal water management, Evap:Inflow was related to lake depth (β = -0.31) and surface inflow (β = -0.44); vertical decline was related to annual climate (e.g., precipitation β = -0.18) and water management (β = -0.21); and horizontal decline was largely related to vertical decline (β = 0.73) and lake morphometry (e.g., depth β = -0.18). Anthropogenic effects varied by ecoregion and likely reflect differences in regional water management and climate. In the West, water management indicators were related to greater vertical decline (β = 0.38), whereas in the Midwest, these indicators were related to more stable and full lake levels (β = -0.22) even during drought conditions. National analyses show how human water use interacts with regional climate resulting in contrasting impacts to lake hydrologic variation in the US.

Manipulation of Electrode Composition for Effective Water Management in Fuel Cells Fed with an Electrically Rechargeable Liquid Fuel

The liquid fuel cell, with its high energy density and ease of fuel handling, has attracted great attention worldwide. However, its real application is still being greatly hindered by its limited power density. Hence, the recently proposed and demonstrated fuel cell, using an electrically rechargeable liquid fuel (e-fuel), is believed to be a candidate with great potential due to its significant performance advancement. Unlike the conventional alcoholic liquid fuels, the e-fuel possesses excellent reactivity, even on carbon-based materials, which therefore allows the e-fuel cell to achieve superior performance without any noble metal catalysts. However, it is found that, during the cell operation, the water generated at the cathode following the oxygen reduction reaction could lead to a water flooding problem and further limit the cell performance. To address this issue, in this work, by manipulating the cathode composition, a blended binder cathode using both Nafion and polytetrafluoroethylene as binding agents is fabricated and demonstrated its superiority in the fuel cell to achieve an enhanced water management and cell performance. Furthermore, using the developed cathode, a fuel cell stack is designed and fabricated to power a 3D-printed toy car, presenting this system as a promising device feasible for future study and real applications.

Water Management for μDMFC with Foamed Stainless Steel Cathode Current Collector

For micro direct methanol fuel cell (μDMFC), water flooding on the cathode seriously affects the performance stability. Additionally, the effect of material and wettability of the cathode current collector (CCC) on the drainage capacity is studied to improve the μDMFC's performance. To this end, a CCC with foamed stainless steel was prepared to assemble the μDMFC due to its absorbency. Further, based on analyzing the gas-liquid two-phase flow characteristics of the μDMFC cathode, it was found that the gradient wettability CCC could accelerate the discharge of cathode water. Hence, the foam stainless steel CCC was partially immersed in a KOH solution to complete the gradient corrosion using its capillary force. Then, four different types of gradient wettability CCC were prepared by controlling the time of chemical corrosion. Finally, the performance of the μDMFC with different gradient wettability CCC was tested at room temperature using electrochemical impedance spectroscopy (EIS) and discharge voltage. The experimental results show that the gradient wettability CCC can improve the performance of the μDMFC by slowing down the rate of cathode flooding. The optimum corrosion time is 5 min at a concentration of 1 mol/L. Under these conditions, the CCC has the best gradient wettability, and the μDMFC has the lowest total impedance. The discharge voltage of the μDMFC with corroded CCC is increased by 33.33% compared to the uncorroded CCC μDMFC. The gradient wettability CCC designed in this study is economical, convenient, and practical for water management of the μDMFC.

Shifts in the phenolic composition and aromatic profiles of Cabernet Sauvignon (Vitis vinifera L.) wines are driven by different irrigation amounts in a hot climate

Wine final color, taste and aroma are closely related to the accumulation of secondary metabolites that may be affected by deficit irrigation applied in viticulture. A two-year study was conducted to assess the different fractions of crop evapotranspiration (ET_c) irrigation replacement on wine composition, addressing the analysis of flavonoids and volatiles under context of global warming. Irrigating with 100% ET_c (full grapevine demand) enhanced wine hue, antioxidant capacity, and some aromas; however, it came with a diminution of flavonoids and a less stable flavonoid profile. Replacing 25 and 50% ET_c in wine grape improved wine color intensity, concentration of flavonoids, and shifted the aromatic profiles. These treatments increased some terpenes and esters which may enhance the desirable aromas for Cabernet Sauvignon, and decreased C6 alcohols related to unpleasant ones. Therefore, despite the warming trends in Mediterranean climates, 100% ET_c irrigation would be not advisable to improve or maintain wine quality, and 50% ET_c was sufficient.

Materials Engineering for Atmospheric Water Harvesting: Progress and Perspectives

Atmospheric water harvesting (AWH) is emerging as a promising strategy to produce fresh water from abundant airborne moisture to overcome the global clean water shortage. The ubiquitous moisture resources allow AWH to be free from geographical restrictions and potentially realize decentralized applications, making it a vital parallel or supplementary freshwater production approach to liquid water resource-based technologies. Recent advances in regulating chemical properties and micro/nanostructures of moisture-harvesting materials have demonstrated new possibilities to promote enhanced device performance and new understandings. This perspective aims to provide a timely overview on the state-of-the-art materials design and how they serve as the active components in AWH. First, the key processes of AWH, including vapor condensation, droplet nucleation, growth, and departure are outlined, and the desired material properties based on the fundamental mechanisms are discussed. Then, how tailoring materials-water interactions at the molecular level play a vital role in realizing high water uptake and low energy consumption is shown. Last, the challenges and outlook on further improving AWH from material designs and system engineering aspects are highlighted.

[Inhibitory Effects of Soil Amendment Coupled with Water Management on the Accumulation of Cd and Pb in Double-Cropping Rice]

The bioavailability of heavy metals in soil and the physiological activities of rice determine the accumulation of heavy metals in brown rice. In this study, a field experiment was conducted in a rice paddy in which the total amount of Cd in the soil did not exceed the national standard, whereas the Cd in rice grains was at risk of overreaching in the suburbs of Guangzhou city. The bioavailability of heavy metals in the soil and the physiological barrier of rice were taken as the starting point. The early and late rice yield, brown rice heavy metal content, Cd and Pb enrichment coefficient, total soil heavy metals, soil physical and chemical properties, and soil Cd and Pb species distribution were investigated under the Si-rich amendment (JD), Ca-Mg amendment (YY), Si-rich amendment+flooding irrigation (JD+YS), and Ca-Mg amendment+flooding irrigation (YY+YS) treatments. The results showed that:① the total ω(Cd) in the soil was only 0.13 mg·kg^-1 in the CK treatment. However, the average ω(Cd) in the grain of early rice reached up to 0.19 mg·kg^-1. The early rice varieties (hybrid rice) had a more vital ability to accumulate Cd and total As in brown rice than that in late rice varieties (conventional rice) but a lower capacity for Pb accumulation. ② JD and YY application alone had no noticeable inhibitory effect on the accumulation of Cd and Pb in brown rice; however, JD+YS and YY+YS treatments significantly inhibited the accumulation of Cd and Pb in brown rice in both early and late rice, especially in the JD+YS treatment, which decreased the Cd and Pb accumulation by 65.8% and 68% for early rice and by 71.43% and 49.15% for late rice, respectively. The primary mechanism of JD+YS was to increase soil pH and maintain a low redox potential to promote soil Cd and Pb to be transformed from acid-soluble to a reduced state and residue state, thus decreasing Cd and Pb to migrate from the soil to the rice. At the same time, it effectively suppressed the absorption and transportation of Cd and Pb by early and late rice via the physiological barrier effect of Si nutrition and the competition for transportation channels between calcium and magnesium ions and cadmium and inhibited the accumulation of Cd and Pb in the brown rice of early and late rice. These results provide a theoretical basis for the exploration and application of the control technologies in the brown rice Cd and Pb resistance and have important practical significance for guiding the safe production in the rice-growing area in South China.

Kaolin Film Increases Gas Exchange Parameters of Coffee Seedlings During Transference From Nursery to Full Sunlight

Increases in water use efficiency (WUE) and the reduction of negative impacts of high temperatures associated with high solar radiation are being achieved with the application of fine particle film of calcined and purified kaolin (KF) on the leaves and fruits of various plant species. KF was applied on young Coffea arabica and Coffea canephora plants before their transition from nursery to full sunlight during autumn and summer. The effects of KF were evaluated through the responses of leaf temperature (T_leaf), net CO₂ assimilation rate (A), stomatal conductance (g _s), transpiration (E), WUE, crop water stress index (CWSI), index of relative stomatal conductance (I_g), initial fluorescence (F₀), and photosynthetic index (PI) in the first 2-3 weeks after the plant transitions to the full sun. All measurements were performed at midday. In Coffea plants, KF decreased the T_leaf up to 6.7°C/5.6°C and reduced the CWSI. The plants that were not protected with KF showed lower A, g _s, E, and I_g than those protected with KF. C. canephora plants protected with KF achieved higher WUE compared with those not protected by 11.23% in autumn and 95.58% in summer. In both Coffea sp., KF application reduced F₀, indicating reduced physical dissociation of the PSII reaction centers from the light-harvesting system, which was supported with increased PI. The use of KF can be recommended as a management strategy in the transition of Coffea seedlings from the nursery shade to the full sunlight, to protect leaves against the excessive solar radiation and high temperatures, especially in C. canephora during the summer.