Water Production Research Articles

Migratory behaviour of humpback whales in the southeastern Pacific under climate change.

Humpback whales, a species of baleen whale occurring in all oceans globally, undergo seasonal migration between their breeding grounds in tropical warm waters and high latitude feeding grounds. Using multiple years of satellite tracking data, we modeled the effect of oceanic conditions on the movement behaviour of 42 humpback whales belonging to the Southeastern Pacific population (also known as Breeding Stock G) during their migration from breeding grounds in Costa Rica, Panama and Ecuador to feeding grounds in waters around the Antarctic Peninsula. We report evidence that during their migration, humpback whales engage in a movement behaviour frequently associated with feeding, and that this behaviour was more likely to occur in relatively more productive waters. We show that whales partly rely on cues they perceive in their immediate environment to initiate their southward migration, but also on their memory of oceanic conditions on their feeding grounds, timing their arrival with the complete melting of sea ice which triggers a bloom of krill in the Antarctic Ocean. Overall, our findings suggest that humpback whales integrate information they gather from their immediate environment to predict the oceanic conditions at distant locations and adjust the timing of their migration, maximizing their interaction with their preys. However, it is unclear if humpback whales will fully succeed in tracking their preys in a rapidly changing climate and ensure the long-term persistence of the species.

Predicting carbon peak at the provincial level using deep learning

Abstract Assessing carbon peak status is crucial in designing mitigation strategies for provinces to mitigate CO2 emissions while maintaining economic development. This study proposes a comprehensive research framework to evaluate carbon peak status at the provincial level. The framework involves identifying the critical emission sources and their primary contribution sectors using the LASSO regression method, predicting the CO2 emissions of critical sources using recurrent neural networks, and exploring mitigation schemes using scenario analysis. This study uses Guizhou Province as an example and analyzes the CO2 emissions of 17 energy consumption types and one production process in 47 socio-economic sectors and discovers that: ① Between 1997 and 2005, the most critical sources of CO2 emissions were the consumption of Raw Coal; ② Between 2006 and 2021, the critical sources of emissions were the consumption of Raw Coal, Other Washed Coal (OWC), and Diesel Oil, and one industry process (Cement Production Process, CPP); ③ Between 2006 and 2021, the primary contribution sector for Raw Coal and OWC emissions is the Production and Supply of Electric Power, Steam, and Hot Water (PSEPSHW) sector. The main contributors to Diesel Oil emissions are the Transportation, Storage, Post and Telecommunication Services (TSPTS), and Other Services (OS) sectors. This study projects that the rising trend in total CO2 emissions will continue from 2022 to 2040 and that emissions will not yet reach their peak by 2030. Furthermore, CO2 emissions from Raw Coal consumption and CO2 emissions from Diesel Oil consumption will continue to increase. These are crucial when designing mitigation schemes for total CO2 emissions. The scenario analysis presents three mitigation schemes for Raw Coal and Diesel Oil emissions that have the potential to reverse the upward trend in CO2 emissions.

Machine learning-based optimization and dynamic performance analysis of a hybrid geothermal-solar multi-output system for electricity, cooling, desalinated water, and hydrogen production: A case study

Machine learning-based optimization and dynamic performance analysis of a hybrid geothermal-solar multi-output system for electricity, cooling, desalinated water, and hydrogen production: A case study

A game-theoretic framework for sustainable water allocation in agriculture: Enhancing economic and water efficiency in Akrotiri district (Cyprus).

Water scarcity is an escalating issue in Mediterranean countries, including Cyprus, where climate change, population growth, rapid urbanization, and economic development place significant pressure on water resources. This study focuses on optimizing the allocation of recycled water for agricultural use in the Akrotiri district, using a game theory approach to maximize net benefits (NB) associated with crop production by considering conventional and nonconventional water resources. A linear optimization framework is developed in which eighteen crop types act as players in a cooperative game, contributing to an overall benefit- and cost-sharing model. Optimal water allocation schemes prioritize crops with high economic productivity and low water demand, enhancing both sustainability and profitability. Based on the available water for irrigation in 2022 (baseline case), the NB is 23 million euros whereas the required subsidies, sourced from external entities, amount to 2 million euros. Groundwater recharge via managed aquifer recharge (MAR) is included as a scenario leading to a similar NB but increases subsidies to 3.5 million euros. Additional scenarios explore losses from aging infrastructure (increase of subsidies up to 70%), water quality constraints due to the presence of pollutants (NB and subsidies are 15 and 4 million euros, respectively), various storage strategies (reduction of subsidies about 20% of the baseline value) and future scenarios based on projected climatic conditions, resulting in the highest subsidies of nearly 9 million euros. This methodology offers a robust decision-making tool for policymakers and planners, helping to navigate the complexities of water allocation under uncertain future climatic conditions.

Spatiotemporal evolution of ground movement in coal seam gas regions: Insights from InSAR.

The exploration and production of coal seam gas (CSG) are growing worldwide. The expanding CSG industry in Australia has raised concerns about land subsidence and its potential environmental impact. Comprehensive monitoring and analysis are required to understand ground movement in CSG regions to support sustainable environmental management. This study employs Interferometric Synthetic Aperture Radar (InSAR) data from 2015 to 2023 to investigate the spatiotemporal ground movement patterns in the Surat Basin. We confirmed the spatial overlap of land subsidence and CSG footprints. Group-based analysis based on distances to CSG wells was conducted to understand the driving factors of ground movement. For the non-CSG area, high-clay soil coincides with more extreme ground movement; no consistent correlation can be identified between rainfall and ground movement; cropping lands show higher movement variation; the correlation between ground movement and water levels in the alluvium is not statistically significant. For the CSG region, a general linear function between subsidence and the cubic root of water and gas production is observed; the influence of coal thickness on subsidence variation is not obvious; bridging is unlikely to happen beyond a few months in the study area; a subsidence time series is derived allowing an estimate of expected subsidence over 17years. Our findings provide valuable knowledge to support sustainable CSG management and regulatory decision-making. The research contributes to the broader understanding of anthropogenic impacts on ground movement in subsurface resource extraction regions.

Modelling the alpha and beta diversity of copepods across tropical and subtropical Atlantic ecoregions

Copepods, the most abundant individuals of the mesozooplankton, play a pivotal role in marine food webs and carbon cycling. However, few studies have focused on their diversity and the environmental factors influencing it. The objective of the present study is to model the alpha and beta diversity of copepods across the tropical and subtropical ecoregions of Atlantic Ocean using both taxonomic and functional approaches. The study used a dataset of 226 copepod species collected by stratified plankton hauls (0–800 m depth) across the tropical and equatorial Atlantic, from oligotrophic waters close to the Brazilian coast to more productive waters close to the Mauritanian Upwelling. To perform the functional analysis, six traits related to the behaviour, growth, and reproduction of copepods were selected. Several alpha diversities were estimated using taxonomic metrics (SR, Δ+, and Λ+) and functional metrics (FDis, FEve, FDiv, FOri, FSpe), and modelized with GAM model across spatial and environmental gradients, and day/night. The overall and two components of β-diversity (turnover and nestedness) were shared between depth and stations. The surface layers of stations from oligotrophic, equatorial, and Cape Verde ecoregions displayed higher values of taxonomic α-diversity. More unpredictable were the facets of functional α-diversity, although they showed a tendency to be positive with depth during the daytime. The GAM analysis revealed spatial gradients as the key factors modelling the taxonomic α-diversity, whereas depth was the most relevant for functional α-diversity. The turnover component drove taxonomic β-diversity in depth and station, whereas the nestedness component acquired relevance for the functional β-diversity. The taxonomic structure of the copepod community varied spatially across depths and ecoregions, but this was not linked to functional changes of the same magnitude.

Dynamic Water and Fertilizer Management Strategy for Greenhouse Tomato Based on Morphological Characteristics

A dynamic management strategy for water and fertilizer application based on morphological characteristics was developed to enhance water use efficiency (WUE) and fruit yield in greenhouse-cultivated tomato (Solanum lycopersicum L.). Multivariate regression analysis was employed to determine the baseline water and fertilizer requirements and to evaluate the effects of varying irrigation and fertilization regimes on fruit yield and WUE. A coupled irrigation–fertilization experiment was conducted, and regression models were established to describe the changes in stem diameter and plant height under these regimes. These models were validated experimentally. The results showed that irrigation significantly influenced both tomato fruit yield and WUE, while fertilization significantly impacted yield, but not WUE. No interactive effects between irrigation and fertilization were observed for either parameter. Stem diameter and plant height were positively correlated with the irrigation and fertilization levels. The proposed dynamic management strategy improved fruit yield by 6.9% and 14.7% under the basic and well-irrigated/fertilized conditions, respectively, compared to that of the fixed regime. Furthermore, model implementation increased WUE by 6.93% and 43.17% and improved the economic benefits by 4.9% and 20.6% under the respective conditions. This provides a practical and effective tool for optimizing water and fertilizer management in greenhouse tomato production, contributing to resource-efficient and high-yield farming practices.

Morpho-physiological and water use performance of soybean cultivars under drought stress at early growth stages

Drought is an important environmental stress for soybean (Glycine max (L) Merr.), which frequently occurs under second-crop conditions in the Mediterranean region of Türkiye and negatively affects early plant growth. In this study, we investigated the effects of drought stress (soil water content maintained at a constant 50% field capacity) on the early growth stage (V3 stage) of different soybean cultivars (Ataem-7, BATEM Erensoy, Göksoy, and Lider). Twenty-seven-day-old soybean plants were exposed to drought stress for 20 days. Morphological (plant height, root length, seedling fresh and dry weight, root fresh and dry weight, and leaf area), physiological (leaf temperature, chlorophyll rate (CR), leaf relative water content (RWC), and electrolyte leakage (EL)), and water use (total water consumption (TWC), and water use efficiency (WUE)) traits were assessed. The results revealed a significant decrease in plant height, root length, leaf area, root and shoot fresh and dry weights, and RWC, and an increase in CR under drought stress. Although Lider and BATEM Erensoy exhibited better growth than the other cultivars under control conditions, their root and shoot growth decreased significantly under water stress. Notably, Ataem-7 presented a lower TWC and WUE difference between the drought treatment and the control, and this cultivar efficiently used water for dry matter production in the shoot and root parts. As a result, there were significant genotypic differences in drought susceptibility among the soybean cultivars, and Ataem-7 showed greater tolerance to drought than the other soybean cultivars did during the early growth stage.

Using winery effluents for cultivating microalgae as bio-additives for vineyards

Abstract The pursuit of sustainable food production and efficient water management has fostered collaborations among academia, industry, and producers to explore innovative business models. One such initiative involves cultivating microalgae using effluents from the wine production industry, transforming waste into valuable products, and creating circular economic benefits. Wineries can repurpose their effluents to grow microalgae, generating new revenue streams while promoting sustainability. Although microalgae biomass grown in winery effluents is unsuitable for direct human consumption due to potential contamination risks from the pollutants and microorganisms present in such effluents, it is rich in essential nutrients like phosphorus, nitrogen, and carbon, making it ideal for use as agro-industrial additives. The REDWine project investigates this potential by focusing on producing Chlorella vulgaris biomass as an agricultural product. The study focused on incorporating red wine production effluents in culture media to promote microalgae mixotrophic growth, conducted in 250 mL Erlenmeyer flasks and a 1700 mL photobioreactor. The findings are promising, despite challenges such as growth inhibition and microbial contamination at higher effluent concentrations. Chlorella vulgaris demonstrated significant growth even at effluent concentrations of 30% (v/v), provided that the concentration of polyphenols in effluents is low, with optimal biomass productivity observed at 10% (v/v). This highlights the feasibility of using winery effluents to cultivate microalgae for sustainable agriculture. This study highlights the potential of using winery effluents to produce C. vulgaris strain A4F_Ma016 biomass, opening new avenues for innovative approaches to sustainable agriculture and the circular economy.

DEVELOPMENT OF AN IMPROVED LOW-COST SOLAR STILL FOR THE PRODUCTION OF POTABLE WATER FOR REGIONS WITH LOW SOLAR IRRADIANCE

Many developing countries are faced with inadequate access to potable water, especially in rural and peri-urban areas, where available freshwater is unsuitable for domestic use. Desalination is a potential solution for purifying polluted or saline water, but common methods are energy-intensive, driving interest in more economical options like solar distillation. Solar distillation, which uses a solar still for water purification, is a promising method but is often limited by low productivity. Single-basin solar stills typically achieve less than 5 litres of freshwater per square meter per day, necessitating further research to enhance output. The primary objective of this study was to develop a cost-effective solar still by incorporating paraffin wax as a phase change material coupled with a heating element (soleplate of a solar pressing iron) to boost productivity. Findings showed that productivity increased with the mass of paraffin wax, reaching a maximum value of 8.6 liters per square meter. Productivities were recorded as 0.75 litres per square meter for the passive solar still, 4.2 litres per square meter for the active solar still, and a peak of 8.6 litres per square meter for the enhanced solar still, reflecting a 104.8% increase in productivity. With a basin water volume of 3 litres, the conventional solar still reached a maximum temperature of 41.2°C, while the enhanced solar still achieved 89.6°C. The cost of water production from the solar still was estimated at $0.01 per litre.

Active Thermal Field Integration for Marangoni‐Driven Salt Rejection and Water Collection

AbstractUsing solar energy to drive seawater desalination via solar steam generation (SSG) is a sustainable strategy for clean water supply. The weak efficiency and poor durability due to salt deposition severely restrict practical SSG operation. Traditional solar evaporators are difficult to simultaneously guarantee efficient evaporation and long‐term salt rejection due to increased salinity. Herein, to tackle this dilemma, a thermal gradient fabric (TGF) evaporator with an auxiliary active thermal field is constructed. Different from traditional works where additional energy resources with improved evaporation rate exacerbate salt accumulation, the auxiliary active thermal field is well integrated with external solar energy to boost ion circulation through moderate Marangoni flow, leading to a continuous salt rejection and superior energy utilization under high‐salinity desalination. The accelerated evaporation rate (2.42 kg m−2 h−1) and superior salt resistance (30 days of desalination in 10 wt.% brine) are simultaneously achieved through optimized thermal field construction. An outstanding water collection rate (5.84 kg m−2) is observed during high‐salinity outdoor desalination, which proves the practical purification ability. This study provides new insight into the construction of active thermal fields for efficient and sustainable clean water production, is believed.

Assessing Geothermal Energy Production Potential of Devonian Geothermal Complexes in Lithuania

Lithuania is a Baltic European country which shares borders with Poland, Belarus, Latvia, and Russia and has a geothermal anomaly in the southwestern region. It consists of two main geothermal complexed, i.e., Devonian and Cambrian with a temperature of up to 40 °C (at a depth of 1000 m) and 96 °C (at a depth of 2000 m), respectively. The Devonian complex is composed of an unconsolidated sandstone formation with porosity and permeability in the range of 4–31% and 200 mD–6000 mD, respectively, and these make it a favorable candidate for a low enthalpy geothermal complex because of the high water production rates. This study evaluates the geothermal potential in the Devonian complex of the selected sites for commercial development. The study utilizes the mechanistic modelling approach including uncertainty management to forecast the water production rates and estimate the power generation capacity. Lastly, the study reveals that it is feasible to produce 6 MW to 60 MW of power from the existing vertical wells for a period of 25 years. Furthermore, reactive transport modelling also proves that there is dissolution and precipitation of the minerals near and away from the wellbore, respectively, which impairs the reservoir quality and further concludes that there is an effect of time on re-injection which should be considered to enhance the reservoir quality for future operations. In addition to that, no effect of the re-injection temperature of the produced water is observed.

Biofacies Analysis of Zanclean Sediments in Virginia: Unraveling the Past Through Benthic Foraminifera

Early Pliocene sedimentary deposits are exposed at the surface along the James and York Rivers, across southeastern Virginia. The Zanclean age (5.33–3.60 Ma) Sunken Meadow Member of the Yorktown Formation records a relatively large-scale marine transgression in the Salisbury Embayment. A total of 15 samples were collected from an outcrop near Spring Grove, VA, for grain-size analysis and to document benthic and planktic foraminiferal assemblages. The sediments are generally moderately well-sorted, shelly fine sands. A total of 48 benthic taxa were recorded from the Sunken Meadow Member, though only 14 taxa occurred in proportions high enough to be included in the Q-mode cluster analysis (>3% of the total assemblage). Low numbers of planktic foraminifera indicate relatively shallow water deposition. Biofacies analysis shows three distinct biofacies groups in the Sunken Meadow Member and the benthic foraminiferal community shifts throughout the unit are indicative of changes in nutrient availability, surface productivity, and bottom water oxygenation. The results indicate a middle to outer neritic depositional environment similar to modern conditions found south of Cape Hatteras, NC.

Green solutions for treating groundwater polluted with nitrates, pesticides, antibiotics, and antibiotic resistance genes for drinking water production.

The present study evaluates for the first time the seasonal performance of an innovative green groundwater treatment. The pilot plant combines microalgae-bacteria treatment and a cork-wood biofilter to reduce nitrates, pesticides, antibiotics (ABs), and antibiotic resistance genes (ARGs) from groundwater. Groundwater had nitrate concentrations ranging from 220 to 410mg/L, while ABs (sulfonamides and fluoroquinolones) and pesticides (triazines) were detected at concentrations ranging from a few ng/L to 150ng/L. Only the gene targets sul1, tetM and the class 1 integron-integrase gene (intl1) were detected in the groundwater. The microalgae-biofilter treatment system effectively removed 15%-98% of nitrates, depending on the season, and consistently eliminated over 90% of ABs and pesticides year-round. Among the components of the treatment system, the microalgal system was the most effective at removing ABs and pesticides. However, the cork-wood biofilter showed superior performance in reducing the bacterial load in groundwater, achieving more than a 1-log reduction in the absolute abundance of genes such as sul1 and intl1. The accumulation of ABs and pesticides in microalgae biomass was minimal or undetectable (<20ng/g of fresh weight). Overall, our results indicate that the microalgae-biofilter treatment plant is an effective solution for significantly reducing nitrates, antibiotics, and pesticides from groundwaters, while also producing a valuable biomass, and meeting drinking water standards during warmer months.

Thermodynamic Analysis of Pumped Thermal Energy Storage System Combined Cold, Heat, and Power Generation

Aiming at problems such as the low efficiency of renewable energy conversion and the single energy flow mode, this paper proposes a heat pump energy storage system combining cold, heat and power generation to achieve the purpose of diversified utilization of renewable energy. The system is suitable for buildings requiring cooling, heating/domestic hot water production and electricity. This paper mainly uses MATLAB for numerical calculations, selects several key cycle parameters to calculate and analyze the thermodynamic performance of the system, and uses the genetic algorithm and TOPSIS decision method to carry out fine design of the system working conditions. Through the multi-objective optimization calculation and the optimal solution, the system can achieve a total energy efficiency of 2.39 and a high thermal economic performance, indicating that the system can achieve the goals of cooling, heating water and power supply and providing ideas for the application of the multiple energy storage system.

Numerical simulation of R134a evaporation in a cold water production system

Abstract In this paper, we introduce a numerical model designed to analyze the evaporation process of R134a refrigerant within a cold water production system. Using the ANSYS Fluent CFD software, our simulation solves the Navier–Stokes equation, thus offering insights into the system’s flow dynamics. Our investigation underscores the efficacy of CFD as a reliable tool for modeling and forecasting flow behaviors within complex systems. Specifically, we delved into the impact of varying the empirical coefficient in the Lee model. Our results indicate that augmenting the coefficient value amplifies the R134a flow rate at the evaporator outlet. Notably, a coefficient value of 0.25 closely matches the experimental flow rate. Furthermore, we analyzed the ascending velocity of R134a vapor, achieving a robust agreement between our numerical simulations and experimental observations. This study underscores the potential of numerical modeling in enhancing our understanding and prediction of refrigerant evaporation dynamics within cooling systems.

The Impact of Employing Nanofluids on the Sustainable Performance of Solar Desalination Systems

Nanofluids have been extensively used in the latest years to develop the effectiveness of several energy systems owing to its promising thermo-physical and visual features. In particular, Solar desalination systems (SDSs) are one of the essential methods and technology for water distillation that still depend on a green and sustainable source of energy. It is associated with eco-friendly structure, well-documented theory, simplicity, and remarkably higher energy compared to other renewables. Nanofluids play a dynamic role in the reduction of energy consumption and enable the production of more water from desalination plants. This paper provides a display of the major advances collected works about the employment of nanofluid tools in solar desalination systems. Many attempts have been made in order to discuss existing challenges as well as several applications with relevant comparisons along with illustrated potential impacts of various nanofluids on performance. Distinctive addition, that has been effectively linked between the sustainable performance and using nanofluid in solar desalination systems. This review indicates that the using nanofluids in solar desalination systems (SDSs) enhanced its sustainable performance and increased its productivity.

Enhanced Photoelectrocatalytic Performance of ZnO Nanowires for Green Hydrogen Production and Organic Pollutant Degradation.

With growing environmental concerns and the need for sustainable energy, multifunctional materials that can simultaneously address water treatment and clean energy production are in high demand. In this study, we developed a cost-effective method to synthesize zinc oxide (ZnO) nanowires via the anodic oxidation of zinc foil. By carefully controlling the anodization time, we optimized the Zn/ZnO-5 min electrode to achieve impressive dual-function performance in terms of effective photoelectrocatalysis for water splitting and waste water treatment. The electrode exhibited a high photocurrent density of 1.18 mA/cm2 at 1.23 V vs. RHE and achieved a solar-to-hydrogen conversion efficiency of 0.55%. A key factor behind this performance is the presence of surface defects, such as oxygen vacancies (OVs), which enhanced charge separation and boosted electron transport. In tests for waste water treatment, the Zn/ZnO-5 min electrode demonstrated the highly efficient degradation of methylene blue (MB) dye, with a reaction rate constant of 0.4211 min-1 when exposed to light and a 1.0 V applied voltage significantly faster than using light or voltage alone. Electrochemical analyses, including impedance spectroscopy and voltammetry, further confirmed the superior charge transfer properties of the electrode under illumination, making it an excellent candidate for both energy conversion and pollutant removal. This study highlights the potential of using simple anodic oxidation to produce scalable and efficient ZnO-based photocatalysts. The dual-function capability of this material could pave the way for large-scale applications in renewable hydrogen production and advanced waste water treatment, offering a promising solution to some of today's most pressing environmental and energy challenges.

Improving groundwater treatment decisions using Giardia and total aerobic spores to assess surface water influence

ABSTRACT Giardia and Cryptosporidium detection in public water supply (PWS) ground water is rare. PWSs are identified as ground water under the direct influence of surface water (GWUDI) using microscopic particulate analysis (MPA) to determine GWUDI. A Canadian dataset of 1,221 samples from 590 ground water devices was collected during the years 2006–2020. Samples were analyzed using the suggested MPA method (for diatoms), for total aerobic spore (TAS), and for parasitic protozoa (EPA Method 1623) (727 samples using the EPA MPA-suggested method, 494 samples using US EPA Method 1623). Giardia cysts were found in 21 samples collected from 16 drinking water production devices. Cryptosporidium oocysts were found in three devices, co-occurring with Giardia. These detections in routine PWS samples using US EPA Method 1623 are the most robust reported detections worldwide. A generalized linear model was used to determine the co-occurrence of TAS or diatom with Giardia and demonstrated that diatoms supplemented by TAS were better than diatoms alone. Diatoms and TAS have complementary parameter sensitivity and specificity when analyzed by sample and by device, i.e. sensitivity (by sample): TAS 78%; diatoms 24% and specificity (by device): TAS 39%; diatoms 87%.

First documented observation of feeding behaviour of humpback whales (Megaptera novaeangliae) in its breeding range off the southern coast of Tanzania

Feeding and breeding activities of humpback whales (Megaptera novaeangliae) are generally understood to be geographically and temporally separated, with feeding activities taking places in the higher latitudes and breeding in lower latitudes. However, humpback whales may supplement their energy budgets by feeding outside of their polar foraging grounds, with opportunistic feeding behaviour being observed in mid-to-low latitudes globally. The records of supplementary feeding during migration in the southern hemisphere have been documented for various breeding stocks, with no records for the East African stock. We present the first to our knowledge record of the humpback whales feeding events in the coastal waters of Tanzania, that have been recorded on the dedicated boat surveys conducted during the humpback whales breeding seasons in 2023 and 2024 off Mnazi Bay in Mtwara region. Demonstrated behavioural plasticity may play an important role in adaptation strategies to global environmental changes and prey availability fluctuations, all of which affect recovering populations. Mnazi Bay seascape and its vicinity is an important habitat for at least 11 species of cetaceans documented, all of which depend on its productive waters for foraging, socializing and as a nursery for migrating humpback whales. This record underpins the importance of the protection of this habitat. However, future studies are needed to confirm and understand the details of the observed supplementary feeding behaviour of the humpback whales and the potential reasons behind its occurrence in Tanzania.