Water Types Research Articles

Comparing the Growth Rates of Ipomoea aquatica Using Washed Rice Water From Different Rice Varieties

Numerous agricultural sectors rely on chemical fertiliser to accelerate crop development, as demand continues to expand each year. Synthetic fertilisers may leak into groundwater, increasing its toxicity and resulting in water contamination. Alternatives such as washed rice water may be utilised to mitigate the environmental impact of chemicals. This research aims to assess the effects of washed rice water on the growth rate of Ipomoea aquatica. Three types of rice water were used in this study: washed white rice water, washed brown rice water, and washed sticky rice water. Two of the rice water served as the control and each was treated with distilled water and NPK fertiliser. Significant values were determined using Analysis of Variance (ANOVA) and post-hoc tests for multiple comparisons. Resultantly, washed white rice water demonstrated the most significant effect in increasing the growth of the plant height, length of root, number of leaves, circumference of the stem and suitability of soil pH. Alternative methods such as washed white rice water could be employed to reduce the cost of agricultural operations to protect the environment from further degradation.

Monitoring soil salinization and waterlogging in the northeastern Nile Delta linked to shallow saline groundwater and irrigation water quality

AbstractSoil salinization and waterlogging are critical environmental issues affecting agricultural productivity and cultural heritage preservation, particularly in arid regions. This study investigated soil degradation processes in the archaeologically and agriculturally significant northeastern Nile Delta of Egypt. The objective was to assess the severity of soil degradation and identify key drivers related to water resources and soil characteristics to aid in the development of management strategies. The research employed a multi-faceted approach, including hydrochemical analyses (of groundwater, irrigation water, and soil), water quality indices calculations, statistical analyses, and satellite data. The results revealed high levels of soil salinization in the northern and central areas, with 64% of soil samples classified as strongly and very strongly saline. Soil chemistry indicated salinization sources linked to sodium chloride dominance. Satellite data from Sentinel-2 images and SRTM digital elevation data showed widespread severe waterlogging in the northern lowlands. The Irrigation Water Quality Index (IWQI) values indicated that 87.5% of irrigation water samples posed severe restrictions due to high salinity and sodium hazards, which were mismatched with the low soil permeability observed in 81% of the collected samples exhibiting clay texture and covering most of the study area. Furthermore, shallow groundwater at depths of 0.5–3 m with high salinity was detected, where total dissolved solids exceeded 20,000 mg/L, and Na-Cl water types prevailed, indicating saltwater intrusion. A strong positive correlation (r > 0.83) was found between shallow saline groundwater and soil salinity. The combination of poor irrigation water quality, shallow saline groundwater tables, and low-permeability soils created a synergistic effect that severely compromised soil health and agricultural productivity. It also posed severe risks to the structural integrity of archaeological sites and buried artifacts through accelerated physical and chemical weathering processes. This necessitates an urgent mitigation strategy to combat soil degradation in this critical area.

Current water contact and Schistosoma mansoni infection have distinct determinants: a data-driven population-based study in rural Uganda

Water contact is a key element of the system of human-environment interactions that determine individual exposure to schistosome parasites and, in turn, community transmission. Yet, there is a limited understanding of the complexity of water contact. We characterised patterns and determinants of water contact within the large-scale SchistoTrack study on 2867 individuals aged 5-90 years in Eastern and Western Uganda, employing Bayesian variable selection and advanced statistical modelling. We found a 15-year gap between the population-level peak in water contact (age 30) and infection (age 15) with practically no correlation (ρ = 0.03) between individual-level water contact and infection. Adults had higher water contact than children, and 80% of individuals with water contact lived within 0.43 km of water bodies. Domestic water contact was most common for children and women, while occupational water contact was most common for men. Water contact was positively associated with older age, fishing or fish mongering occupations, the number of water sites, and type (beach/pond/swamp), and lower village-level infection prevalence. Only older age and fishing were positively, though inconsistently, associated with infection status/intensity. By providing profiles of at-risk groups, and suitable water contact metrics, our research opens avenues for spatially-targeted interventions and exposure monitoring in endemic countries.

Review on the Impacts of the Samalas Eruption (1257 CE) to the Hydrogeological Conditions of Mataram, Lombok, Indonesia

This paper examines the local impacts of the 1257 CE Samalas eruption in the Mataram plain in relation to the hydrogeological conditions. Data from several previous studies in the Mataram plain is summarized and then reinterpreted. Data collected from new fieldwork is also presented. This review summarizes hydrogeological conditions into several categories, i.e. stratigraphy, aquifer formation, groundwater quality, and evolution. Two coring data were evaluated, which showed that Mataram plain has a relatively thick alluvial layer with a dominant material of sand mixed with pumice from the reworked deposit of the 1257 CE Samalas eruption. The sediment from this eruption formed a freshwater aquifer layer up to ~18 m deep. Using resistivity data, the aquifer layers in the studied area were characterized as unconfined aquifer, aquitard, and semi-unconfined aquifer. Seven water samples show that the groundwater in the studied area is in good condition, which indicates the bicarbonate water type. The results of the analysis show that the impact of the 1257 CE Samalas eruption on the hydrogeology of Mataram is considered a positive impact, i.e. forming an unconfined aquifer containing freshwater that is good for domestic uses.

Investigating formation water variability in the Búzios oilfield (Santos Basin) using cluster analysis and hydrogeochemical modeling

The characteristics of formation waters play a crucial role in production development projects within Pre-Salt oil fields in the Santos Basin, offshore southeastern Brazil. This study investigated the compositional variations of brines of the Búzios Field (northeast of the Santos Basin), proposing for the first time an extensive hydrochemical mapping of the Pre-Salt aquifers and identifying nuances of connectivity. A comprehensive methodology was employed, including analysis of pressure gradients, cluster analysis, and hydrogeochemical modeling to classify different types of brine and understand their behavior under reservoir conditions. A hydrochemical classification routine was applied to 129 formation water samples, identifying seven distinct clusters using the unsupervised k-means algorithm. This clustering process efficiently differentiated representative, non-representative, and contaminated samples. The hydrochemical composition of the formation waters varied among the four hydraulic compartments identified in the field, with their boundaries defined by permeability barriers. Compared with the central portion of the field (regional aquifer), where salinities predominantly range from 155,000 to 185,000 mg/L of NaCl, enrichment of specific ions was observed at the field's extremities, such as boron (northeast), barium and lithium (north), and bicarbonate (west). These hydrochemical differences lead the brine salinities at the field's extremities to exceed 225,000 mg/L of NaCl. Hydrogeochemical modeling provided insights into the pH levels of each brine under reservoir conditions, showing a decrease of between 23 and 32% compared to surface pH values. The speciation analysis showed positive strontianite and barite saturation indices in certain types of formation water, indicating potential precipitation. These areas are considered critical for inorganic scaling in production equipment.

Reduced primary productivity and notable resilience of phytoplankton community in the coastal water of southern China under a marine heatwave

Increasing frequency, intensity and duration of marine heatwaves (MHWs) are supposed to affect coastal biological production in different regions to different extents. To understand how MHWs impact coastal primary productivity and community succession of phytoplankton and assess the changes in resilience of phytoplankton communities, we conducted a mesoscale enclosure experiment simulating a marine MHW in the coastal water of southern China. After 8 days of the MHW (+3 oC) treatment, community biomass was significantly lower than the control’s, and primary productivity per volume of water was reduced by about 56%. Nevertheless, the phytoplankton community retrieved its biomass and primary productivity after the temperature was subsequently reset to that of the control. Although the MHW treatment decreased the abundance of diatom and increased the percentages of Synechococcus and Prasinophytes, the main phytoplankton functional types showed positive resilience that allowed the recovery of the phytoplankton community after the MHW. Our results indicate that key phytoplankton functional types in the southern coastal waters of China exhibited significant resilience, recovery, and temporal stability under the influence of the marine MHW by 3 oC rise. However, reduced primary productivity during the MHW period, along with decreased biomass density, might significantly influence secondary producers. In addition, the altered phytoplankton community structure may affect coastal food web processes at least during the MHW period.

Atomistic origin of montmorillonite clay subjected to freeze-thaw hysteresis

The freeze-thaw cycles of frozen soil could significantly affect its thermo-hydro-mechanical-chemical (THMC) properties, causing the frost heaving and thawing settlement. The microscale essence is the water-ice phase transition, but the microscale details are still poorly understood, especially at ultra-low temperatures. Nuclear magnetic resonance (NMR) technology and molecular dynamics (MD) simulation methods were performed to explore the freeze-thaw behaviors of montmorillonite clay under temperature of 210 - 293 K. Then, the water-ice phase transition, freeze-thaw hysteresis, ice nucleation mechanism, and surface effect of clay at an atomistic level were discussed. A classification method of different types of unfrozen water through NMR experiment was proposed, including bulk, capillary, and bound water. Here, it is found that: (1) the freeze-thaw process of frozen soil at the macroscale was essentially the occurrence of ice-water phase transition at the microscale. (2) The freeze-thaw hysteresis was caused by different growth and melting rates of ice crystals, where the ice growth/nucleation on clay surface was more difficult to develop. (3) The surface effect of clay was essential for the ice nucleation and the existence of bound water. For example, little unfrozen water still existed in unfrozen soil even at 213 K. (4) For unsaturated frozen soil, the quasi-liquid water was an essential component of unfrozen water that cannot be ignored. This work could provide an atomistic insight to unravel the atomistic origin of the freeze-thaw mechanism of montmorillonite clay and complement relevant experimental evidence.

Study on an Integrated Water Treatment System by Simultaneously Coupling Granular Activated Carbon (GAC) and Powdered Carbon with Ultrafiltration

The process of using powdered activated carbon (PAC) in conjunction with ultrafiltration (UF) has been widely adopted for the treatment of various types of water and wastewater. However, during the application of this integrated PAC-UF process, PAC tends to adhere significantly to the surface of the UF membrane, which exacerbates membrane fouling. To tackle this issue, this study proposed an innovative water treatment approach that simultaneously integrated granular activated carbon (GAC) and PAC/biochar with UF. In this setup, PAC/biochar was intended to enhance water quality, while the fluidized GAC particles were aimed at reducing membrane fouling and the deposition of PAC/biochar on the membrane surface. We systematically analyzed the operational performance of the integrated systems concerning fouling formation, PAC/biochar attachment, effluent quality, and foulant components. The results indicate that both PAC and biochar effectively improved effluent quality in terms of chemical oxygen demand (COD) and hardness, although they significantly deposited on the membrane surface during operation. Notably, PAC was more prone to attach to the membrane than biochar, and the fouling in biochar-UF systems was primarily attributed to the attachment of organic foulants rather than biochar itself. By combining with GAC, up to 46.01% of membrane fouling and 96.11% of PAC/biochar attachment were mitigated due to the strong mechanical action of the fluidized GAC particles. Importantly, the inclusion of fluidized GAC did not significantly affect effluent quality. Consequently, the GAC-PAC/biochar systems proposed in this study demonstrated dual benefits of improving effluent quality and ensuring stable operation, thereby providing a viable solution for efficient and sustainable water treatment.

Impacts of blending advanced treated water and traditional groundwater supply on lead and copper concentrations and microbial diversity in premise plumbing

In response to stresses on water demands, some regions augment conventional drinking water sources with alternative water supplies such as desalinated seawater and reclaimed wastewater. The advanced treatment of wastewater by reverse osmosis, microfiltration, and advanced oxidation processes can produce high quality water for potable uses. However, if not appropriately stabilized, the resulting water can be corrosive to metal-based distribution pipes and plumbing materials. We conducted long-term premise plumbing pipe loop experiments with copper pipes containing lead solder to test the impact of the introduction of advanced treated water on the water quality. Advanced treated water (ATW) originally at low pH (<7) and low alkalinity (<10 mg/L as CaCO3) was stabilized with a calcite contactor before being blended with baseline ground water (BLW). The effects of percentages of ATW on the release of lead and copper and on the changes in the microbial diversity were monitored. Experiments monitored metal release from pipes receiving (1) only BLW, (2) a series of blends of BLW and ATW that gradually increased from 25 % to 100 % ATW, and (3) an abrupt switch from BLW to 100 % ATW. Introducing 100 % ATW dramatically increased lead release and simultaneously decreased copper release. Pipe scale analysis showed that the introduction of ATW had destabilized sulfate-containing pipe scales, which exposed the copper pipe surface to galvanic corrosion. The dissolution of scale material was associated with a significant decrease in sulfate concentration in the 100 % ATW which was in agreement with theoretical solubility calculations. The impact of blending ATW on microbial diversity was studied via 16S rRNA gene amplicon sequencing. The composition of the microbial communities changed significantly after water was in contact with the copper pipes in experiments with both BLW and ATW. The type of water recirculating in the pipes affected the structure of the microbial community. The results from this study can be useful for water utilities that are considering potable reuse as they develop strategies to mitigate any adverse impacts of water quality changes.

Hydro-chemical characterization of groundwater using multivariate statistics in Hawassa City, Southern Ethiopia

ABSTRACT This study characterized the hydro-chemical characteristics of groundwater for assessing the possibility of managed aquifer recharge in Hawassa City. A total of 48 water samples were taken from hand-dug wells and boreholes and examined to determine the water type, critical metrics, and key determinants of water quality. Multivariate statistical techniques such as hierarchical cluster, principal component, and linear discriminant analysis were used. The samples were divided into four variable groups and four case cluster groups. The results depicted the water hardness group (C1), soil salinity group (C2), weak and strong acids forming group (C3), and pollution indicator group (C4). Four water types were identified, Na–HCO3 and Ca–Na–HCO3 (87.5%), Ca–HCO3, and Na–Cl. Na–HCO3 was the dominant in hand-dug wells than in deep boreholes, which may account for evaporation or contaminations. Seven principal components with a cumulative variance of 78.58% were also formed. The first two, hardness and salinity, contributed 25.4 and 11.4% variance, respectively. In linear discriminate analysis, three discriminate functions with eight variables were generated, namely pH, K+, Na+, Ca2+, HCO3−, Cl−, BOD5, and COD. Thus, it is revealed that the decline in water quality attributed to natural and anthropogenic causes that require regulation enforcement and higher recharge to reverse the situation.

Haematological and Biochemical Reference Intervals Towards a Proactive Health Monitoring Approach in Norwegian Atlantic Salmon Farming.

Haematological and plasma parameters are used in veterinary medicine as a diagnostic tool, allowing for the early detection of potential health and welfare issues. For the implementation of monitoring strategies, reference intervals (RIs) are needed to know when deviations in those parameters become clinically relevant. Here, haematological and plasma biochemical RIs of Norwegian Atlantic salmon (Salmo salar Linnaeus) are presented for 29 biomarkers. Two subgroups were defined from the reference population based on water type, referred to as pre-adult (freshwater, 166.8 ± 118.4 g, N = 979) and adult (seawater, 2655 ± 2883 g, N = 4941), collected at 93 fish farms along the Norwegian coast. While the influence of various pre-analytical variables on RIs is well documented, aquaculture practitioners cannot always control those variables in the field. Here, RIs were calculated from blood samples collected based on local pre-analytical practices and then further processed under standardised conditions (analytical phase). RIs are therefore considered highly relevant for the application in the field. Finally, when taking blood samples in the field, it is advised to centrifuge whole blood as soon as possible, while plasma parameters investigated were stable for 168 h at 4°C or 72 h at room temperature.

Data-driven effects of human activities and environmental factors on inland aquatic dissolved organic matter in China: Insights from machine learning

Aquatic DOM, a major carbon pool in inland waters, plays a key role in the global carbon cycle and is influenced by human activities and environmental factors. While watershed surveys have identified some drivers of aquatic DOM changes, national-scale knowledge remains limited. Spectral monitoring data from 721 aquatic DOMs in inland China were collected to predict and quantify the spectral properties of aquatic DOMs and the coupled effects of human activities and environmental factors by complete ensemble empirical mode decomposition with adaptive noise (CEEMDAN), random forest (RF) and structural equation modeling (SEM). Our results show that the dataset is relatively evenly distributed in terms of flow regimes, and the data are adequately representative of various types of water in China. Although the performance of CEEMDAN is affected by the skewed distribution of data sampling points (453 and 449 for eastern regions and eutrophic waters, respectively), CEEMDAN effectively processes the spatial sequences of aquatic DOM spectra, which significantly improves the reliability of the machine learning model (by 13%–68%) and reduces the error (by 63%–92%). CEEMDAN-RF and SEM results indicate that longitude and latitude are the most important environmental factors affecting the spectral properties of aquatic DOM through temperature, light and land cover differences, reducing the biogenic properties of aquatic DOM. Unlike observations in small watersheds and estuaries, environmental factors of season, precipitation and salinity have weak effects on aquatic DOM. Furthermore, the biogenic character of aquatic DOM is enhanced by urban human activities, represented by urbanization, population, and impervious land fraction, which have long-lasting and strong impacts on aquatic DOM by driving water eutrophication and enhancing phytoplankton and microbial activity. Our study informs the prediction and quantification of coupled environmental and anthropogenic impacts on aquatic DOM at large scales.

Nanotechnology strategy for inhibition of PARP1 and IL-17A-associated with neurotoxicity in rats exposed to hospital wastewater.

Hospital wastewater (HWW) poses a serious hazard to human health security concerning its high susceptibility to neurodegeneration. Water sources and ecosystems are exposed to a complicated pollution load from a variety of refractory organics and pharmaceutical active composites. This study evaluates the treated newly developed nanocomposite (NiFe2O4) HWW on the neural injury induced by HWW action in rats. Three groups of male Wistar rats were distributed, with eight rats in each: group I: tap water served as a control; group II: HWW; and group III: nano-HWW. Each group was intragastrical administrated with each type of water (2.5 ml/100 g b.wt/6 h) for 28 consecutive days. The open field test and Morris Water Maze assessed behavioral activity and spatial learning 2 days before the last day. The research demonstrated that HWW treated with nanocomposite (NiFe2O4) may exert decreased risks of the neural impairment effect of HWW. This improvement was achieved by reducing the neurotoxicity by lowering nitric oxide contents, lipid peroxidation, acetylcholinesterase, interleukin-17A (IL-17A), and poly(ADP-ribose) polymerase1(PARP1) while restoring the antioxidant biomarkers and neurotransmitter levels (β-endorphin, norepinephrine, dopamine, and serotonin) of the treated groups in the cortex and brainstem and enhancement of the histopathology of the cortex as well. In conclusion, this study introduced a newly developed nanotechnology application for treating HWW to protect from neural injury. The findings of this research have significant value for policymakers, Ministry of Health management, and environmental organizations in their selection of suitable techniques and procedures to optimize hospital wastewater treatment efficiency.

Enhancing the sustainability of cowpea production through the integrated use of fish effluents and animal manure

AbstractThe integration of aquaculture and agriculture in arid and semi‐arid environments is crucial for maximizing water and land productivity, especially considering the increasing global water scarcity and the simultaneous use of water for crop and fish production. A greenhouse study was conducted to determine the effects of fish effluent on the growth, yield parameters, and yield of cowpea (Vigna unguiculata). The experiment involved 13 fertilization treatments, including three types of irrigation water (river water—control, Nile tilapia (Oreochromis niloticus), African sharp‐toothed catfish (Clarias gariepinus), four fertilizers (poultry, cattle, and sheep manures at 10 t ha−1), recommended rate of inorganic fertilizer (150 kg ha−1 of NPK 6‐20‐10), and six mixed treatments with fish effluent and 50% of the applied rate of manure alone (5 t ha−1). The combined use of C. gariepinus effluent + 50% poultry manure significantly increased stem diameter, nodules per plant, pods per plant, and seed yield compared to NPK treatments. The shortest days to reach 50% flowering were obtained with the effluent of O. niloticus + 50% sheep manure, C. gariepinus/O. niloticus + 50% poultry manure, and 10 t ha−1 poultry manure. However, fertilization treatments did not significantly influence the number of branches, pod and root length, number of pods per plant, 100‐seed weight, and leaf chlorophyll concentrations. This study suggests that fish effluents, when combined with manure, can improve plant growth and seed yield, providing a cost‐effective alternative to inorganic fertilizers for smallholder farmers.

Water-Rock Interaction Mechanisms and Hydrochemical Evolution in the Underground Reservoirs of Coal Mines.

Coal-mine underground reservoirs play pivotal roles in water purification through water-rock interactions; however, underlying mechanisms associated with water-rock interactions remain unclear to date. To address this issue, this study considered the underground reservoirs of the Daliuta coal mine, Shendong to conduct the analysis. Through onsite sampling and laboratory simulation experiments, along with hydrochemical-diagram-based analysis, multivariate statistical analysis, and hydrogeochemical simulations, the sources and evolutions of major ions associated with the water of the underground reservoirs were elucidated. Results revealed that the suspended-solid content, turbidity, electrical conductivity, and total dissolved solid concentration in the water at the outlet of the underground reservoirs decreased significantly compared to corresponding values at the inlet. Alteration in the hydrochemical type of water was observed from the Cl·HCO3-Na·Ca, Cl-Na·Ca·Mg, and Cl·SO4-Na types at the inlet of the reservoirs to SO4·Cl-Na at the outlet of the reservoirs. Further, the primary hydrogeochemical processes carried out along the water flow path in the underground reservoirs included mineral dissolution (including halite, silicate, calcite, gypsum, and anhydrite dissolution), pyrite oxidation, cation exchange, and clay-mineral adsorption. Water-rock interactions in the underground reservoirs can be categorized into three stages. The first stage was dominated by dissolution and oxidation, resulting in decreased water pH and overall increased concentrations of total dissolved solids along with major ions in the water. The second stage was dominated by clay-mineral adsorption and cation exchange, resulting in increased water pH and overall concentrations of Na+ and K+ as well as decreased concentrations of Ca2+, Mg2+, and total dissolved solids in the water body. The third stage was characterized by weak water-rock interactions, wherein the concentrations of total dissolved solids along with major ions, as well as the pH of the water stabilized. Thus, our research findings provide important theoretical references for understanding water-purification mechanisms and water-storage-duration optimization in coal-mine underground reservoirs.

Enhanced underwater optical wireless communication using optical code division multiple access with sigma shift matrix code

A high-speed 40 Gbps Underwater Optical Wireless Communication (UOWC) system exploiting code division multiple access is proposed in this paper. Optical Code Division Multiple Access (OCDMA) systems play a crucial role in enhancing transmission capacity by allowing multiple channels to transmit data simultaneously. In this proposed work, four channels each assigned a distinct Sigma Shift Matrix (SSM) code and modulated with a data at 10 Gbps. Laser Diode (LD) sources operating in the green spectrum are used in UOWC systems due to their low attenuation. To ensure the feasibility of implementing the proposed system in real-world environments, the actual scattering and absorption coefficients from five different types of water are considered: Pure Sea (PS), Clear Ocean (CL), Coastal Sea (CS), Harbor I (HI), and Harbor II (HII). The system's performance is evaluated via the Quality Factor (Q-factor), Bit Error Rate (BER), and eye diagrams opening. The simulation results indicate that in PS water, which exhibits the lowest attenuation, the four channels achieve the longest underwater transmission distance of 48 m, with a Q-factor ≥ 4.1, log(BER) ≤ −4.7, and wide eye openings. Since CL and CS have higher attenuation than PS, they enable shorter transmission distances of 27.5 m and 16 m, respectively, while maintaining nearly the same Q-factor, log(BER), and eye diagrams. Conversely, the highest attenuation observed in HI and HII waterbodies results in the shortest underwater spans of 8.2 m and 5.05 m, respectively.

Different States of water in α-Cyclodextrin hydrates

The pressure of saturated and unsaturated water vapor over α-CD·nH2O hydrates has been measured by static method with membrane-gauge manometer under conditions of complete loss of water. The temperature dependences of water vapor pressure have been obtained in the wide range of temperatures (287–469 K), pressures (0.04–34.95 kPa) and water content (0.17 ≤ n ≤ 6.0).The data obtained indicate the presence of water molecules with different volatility in α-CD·nH2O hydrates. Water molecules with lower volatility can be considered “external”, included in the network of intermolecular hydrogen bonds, while water molecules with higher volatility, discovered in our previous study, are considered “internal”, presumably located in the α-CD cavity. For each composition, the amount of “external” and “internal” water has been determined and the equations described the dependence of the content of each type of water on n in α-CD·nH2O have been obtained. The analytical expressions for the lnp – 1/T dependences as well as the values of enthalpy and entropy of processes studied have been calculated. Experimental data were used to obtain the Gibbs energy changes when “external” water molecules bind to the α-CD framework. The values obtained are differed from the values for “internal” water given in our previous study. The phase transition in α-CD·nH2O revealed in our previous study is also observed in this work and its thermodynamic characteristics are in good agreement with the results obtained earlier. The findings have been confirmed by 1H NMR studies.

Low-field MRI study of the 1H distribution and migration in porous sediments during natural gas conversion from methane hydrate

Gas hydrates, crystalline compounds formed from water and guest molecules like methane, are gaining attention as a promising clean energy source. While research has extensively focused on the extraction and transport of natural gas hydrates from offshore marine sediments, the dynamic processes in the porous sediments remain under explored. This study employs low-field Magnetic Resonance Imaging (MRI) to investigate the in-situ formation and dissociation of methane hydrate within a partially saturated stack of glass beads. By integrating advanced MRI techniques, including 1D dhk SPRITE, bulk T1 distribution, and 2D spatial T2 imaging, this research provides a comprehensive analysis of fluid distribution and migration during phase transitions in the porous sediments. Three key findings emerged from the study. First, SE-SPI measurements successfully quantified hydrate and residual water saturation, aligning with previous X-ray CT and high-field MRI studies and validating low-field MRI for hydrate research. Secondly, this study introduced a volumetric approach to T1 and T2 measurements, distinguishing between free and bound water, with characteristic relaxation times for each, confirming the technique's capability to differentiate types of residual water. Finally, spatially resolved T2 relaxation time distributions revealed vertical fluid migration within the pore spaces, identifying an equilibrium zone where inflow and outflow rates were balanced. Overall, this study underscores the effectiveness of low-field MRI as a noninvasive tool for analyzing hydrate-bearing sediments. The findings lay the groundwork for further exploration of hydrate in porous sediments, enhancing our understanding of gas production dynamics in hydrate-rich environments.

Assessing ecological risks and microplastic pollution in a tropical coastal ecosystem: Effects of rainfall variability in Southeast India

Microplastic pollution poses a significant threat to coastal ecosystems, prompting an in-depth investigation into its seasonal fluctuations and ecological impacts. This study examines microplastics in Cuddalore’s coastal waters and sediments across four seasons. Results show varying microplastic concentrations, peaking during the monsoon and pre-monsoon seasons, likely influenced by rainfall variability. Fibers dominate in both water (69–100 %) and sediment samples (66–92 %), with polyethylene and polyethylene terephthalate as the predominant polymer types in water. Sediments exhibit a more diverse polymer distribution, with polypropylene and polyethylene terephthalate being prevalent. Elevated polymer hazard index and potential ecological risk index raise concerns, reaching values of 108930 and 1125, respectively. This underscores the urgency of implementing effective management strategies to safeguard tropical coastal ecosystems from microplastic pollution. This study highlights the complex interplay between seasonal dynamics, rainfall variability, polymer types, and pollution levels, emphasizing the need for proactive environmental management measures.

Groundwater quality assessment for drinking and irrigation purposes in arid to semiarid region of Indus Basin of South Punjab, Pakistan

&lt;p&gt;&lt;a name="_Hlk173243332"&gt;&lt;span style="background-color:white;color:black;font-family:&amp;quot;Times New Roman&amp;quot;,serif;font-size:12.0pt;line-height:150%;"&gt;As the groundwater pollution is increasing, it is crucial to assess groundwater quality and characterize hydrogeochemistry accurately for long term water supply.&amp;nbsp;&lt;/span&gt;&lt;/a&gt;&lt;span style="background-color:white;color:black;font-family:&amp;quot;Times New Roman&amp;quot;,serif;font-size:12.0pt;line-height:150%;"&gt;In this study groundwater samples were collected from 120 locations from Bahawalpur district and analyzed for electrical conductivity (EC), pH, total dissolved solids (TDS), sodium (Na&lt;sup&gt;+&lt;/sup&gt;), potassium (K&lt;sup&gt;+&lt;/sup&gt;), calcium (Ca&lt;sup&gt;2+&lt;/sup&gt;), magnesium (Mg&lt;sup&gt;2+&lt;/sup&gt;), carbonate (CO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt;), bicarbonate (HCO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt;), sulfate (SO&lt;sub&gt;4&lt;/sub&gt;&lt;sup&gt;2-&lt;/sup&gt;), chloride (Cl&lt;sup&gt;-&lt;/sup&gt;), nitrate (NO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt;), fluoride (F&lt;sup&gt;-&lt;/sup&gt;) and heavy metals. The results obtained from the analysis of samples showed that the SAR of nearly 65% of samples collected from Bahawalpur district were in acceptable limit (&amp;lt;6 meq L&lt;sup&gt;-1&lt;/sup&gt;), while 12% found to be unfit for irrigation (&amp;gt;10 meq L&lt;sup&gt;-1&lt;/sup&gt;). Similarly, the RSC values depicted that 8% samples were unfit while 64% samples were falling in the category of fit irrigation water. Most of the water samples were predominantly Ca&lt;sup&gt;2+&lt;/sup&gt;-HCO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; and Na&lt;sup&gt;+&lt;/sup&gt;-HCO&lt;sub&gt;3&lt;/sub&gt;&lt;sup&gt;-&lt;/sup&gt; type, that were controlled by various processes of cation exchange, water-rock interaction, dissolution and evaporation. Some samples fall in the&amp;nbsp;middle of diamond and lower triangles of Piper diagram are showing no dominant type of water (mixed water type) due to the complex influence of rock-water interactions as well as anthropogenic activities. The Water Quality Index (WQI) showed that&amp;nbsp;out of total 120 sampling sites in Bahawalpur the number of excellent water samples were only 2% while 18% water samples were characterized as hazardous. Moreover, the number of samples falling in the categories of good, poor and very poor quality water were 36%, 29% and 13% respectively.&lt;/span&gt;&lt;/p&gt;