Microscopic Level Research Articles

Study on time-varying characteristics and flow behavior of microencapsulated polymer

Due to the challenges posed by high injection pressure and significant viscosity shear loss, conventional polymer flooding methods are unable to effectively meet the urgent demand for enhanced oil recovery in medium- and low-permeability reservoirs. Microencapsulated polymer flooding is a promising solution to address the aforementioned challenges due to its advantages of easy wellbore injection, shear resistance, and delayed thickening. However, there is a lack of research on the release behavior and time-dependent characteristics of microencapsulated polymer and its impact on flow behavior in reservoirs. To address this gap, we conducted a series of experiments, including thermal stability tests, microfluidic chip experiments, and micro-scale oil displacement experiments, to reveal the time-varying behavior generated by the triggered release of microencapsulated polymers. The results showed that microencapsulated polymer can be fully triggered after 8 days of aging at 85 °C, with a viscosity exceeding the initial viscosity by more than 25 times. The release mechanism of the polymer aligned with the Ritger-Peppas model, transitioning from super Case-II transport to anomalous transport, and finally to Fickian diffusion with increasing temperature. During the triggering process, the presence of particles stabilized shear and improved oil displacement, particularly in small pore throats. Higher triggering degrees of the solution resulted in greater flow resistance within the microchannel, effectively suppressing fluid fingering. The oil displacement effectiveness of fully triggered microencapsulated polymer was comparable to that of conventional polymers. This study provides insights into the flow behavior of microencapsulated polymer at a microscopic level, offering valuable references for its application in the field.

Pressure Engineering on Perovskite Structures, Properties, and Devices

AbstractAs a fundamental thermodynamic parameter, pressure serves as an effective tool to control the structures and properties of functional materials. To date, numerous pressure‐engineering methods have been introduced to enhance perovskite structures and devices. This paper comprehensively reviews the advances in understanding the effects of pressure on perovskite materials and devices, encompassing both low and high‐pressure influences. These effects are categorized into six distinct groups based on their underlying mechanisms, detailing the evolution of perovskite structures from macroscopic to microscopic levels, and exploring the interplay between these structures and their functional characteristics. Finally, the current challenges and offer insights into the future prospects for harnessing pressure effects to further develop perovskite structures, properties, and devices are assessed.

Unveiling the Microscopic Origin of Irreversible Capacity Loss of Hard Carbon for Sodium‐Ion Batteries

AbstractThe primary bottleneck hindering the application of hard carbon in sodium‐ion batteries (SIBs) anodes lies in its inadequate initial Coulombic efficiency (ICE). Unclear causes of capacity loss at the microscopic level restrict the improvement of hard carbon anodes. Here, two pivotal stages that influence the structure and composition of hard carbon, namely synthesis, and storage are evaluated; subsequently identifying crucial determinants contributing to irreversible capacity loss. The results suggest that undergrown carbon layers allowing the intrusion of solvent molecules into the interior of the hard carbon is a key factor during the synthesis stage, while the gradual formation of oxygen‐containing functional groups on the surface of the hard carbon is another factor leading to irreversible loss of capacity during storage stage. This research microscopically clarifies the irreversible capacity loss mechanism on hard carbon and provides guidelines for designing and applying high ICE hard carbon for SIBs.

The interface mechanism of ball-milled natural pyrite activating persulfate to degrade monochlorobenzene in soil: Intrinsic synergism of S and Fe species

Ball-milled natural pyrite has been proven to be an efficient and economical catalyst for persulfate (PDS) activation; however, the synergistic interface mechanism between S and Fe species transformation remains a large challenge. Herein, ball-milled pyrite was used in the degradation of monochlorobenzene (MCB) from soil, and the surface characteristics and identification of the S and Fe species in the ball-milled natural pyrite during the Fenton-like reaction were reported. The pyrite/PDS system was found to eliminate 93.8 % of the 95.6 mg/kg MCB in the soil. Ball milling changed the fundamental pathway of reactive species (RS) generation, and the FeIV contribution increased to 33.0 % for MCB degradation. Compared with heterogeneous activation, homogeneous activation induced by dissolved Fe(II) played an important role. Self-oxidation induced by sulfur vacancy sites (SVs) also occurred during MCB degradation (30.8 %). An exploration of the mechanism of the interfacial reaction at the microscopic level revealed that ball milling promoted the formation of SVs and increased the reducibility of S(-II) on pyrite, thus accelerating Fe(III) reduction and Fe(II) dissolution, limiting the generation of an Fe(III) passivation layer at the pyrite–water interface and promoting RS generation for MCB degradation. These findings provide new insights into the interface mechanism for PDS activation in a ball-milled pyrite/PDS system.

Modification of magnetorheological fluid and its compatibility with metal skeleton: Insights from multi-body dissipative particle dynamics simulations and experimental study

Magnetorheological fluid (MRF), as a smart material, plays a pivotal role in sealing equipment. However, the interfacial compatibility between MRF and metal significantly impacts the adhesion of the two phases, which subsequently determines the sealing performance of MRF once it is used as a sealing medium. However, the interface mechanism and dynamical magnetic migration performances between MRF and metals at the microscopic level are not clear. In this study, dissipative particle dynamics (DPD) and multi-body DPD simulations are carried out to examine the settling stability, static wetting characteristics, and magnetic migration ability of MRF droplets incorporating different surfactants. It is revealed that oleic acid stands out as the optimal surfactant for MRF, shedding light on the mechanism of MRF droplet infiltration on metal sheets and unveiling five crucial wetting processes. Furthermore, a thorough comparison among simulation results, experimental findings, and numerical analysis was conducted to verify the reliability of theoretical research on the microscale behavior of MRF. Moreover, investigating the driving characteristics of MRF droplets within a uniform magnetic field confirmed two driving processes: significant deformation and limitation of excessive diffusion. The analysis of the vortical structure within the droplets revealed the presence of diffusion effects caused by magnetic particles. The velocity distribution within the droplets indicated different flow rates, with higher velocities at the core and slower velocities at the edge, suggesting the presence of internal flow patterns.

Prediction of ductile cracking in the titanium alloy forging process

Abstract The control of surface cracking in the forming of titanium alloy forgings is a significant problem in the forging industry. For titanium alloys, the formation of surface cracks is related to temperature, strain rate, and stress state. This study selected the widely used medium to high strength titanium alloy Ti-6Al-4V in the field of forging as the research material, and designed six different shapes of specimens for high-temperature tensile and compression tests. The mechanisms underlying crack formation were analyzed at the microscopic level, and the critical fracture displacement of these tests was extracted. Moreover, their critical fracture strains were obtained through simulations, and a High-temperature damage model was established based on the DF2016 model. The research results showed that cracks through void at grain boundaries propagate and aggregate to form, leading to a fracture mechanism characterized by ductile fracture through micro-pore aggregation. Simulation results demonstrate that the established model accurately predicts the crack of forgings.

Native bubble nuclei for acoustic cavitation in 3D cell cultures

The safety of biomedical ultrasound largely relies on controlling cavitation bubbles in vivo; however, bubble nuclei in biological tissues remain unexplored compared to water. No previous studies have observed where bubble nuclei form in tissues at a microscopic level or how the variation in tissue biomechanical properties can impact the presence of bubble nuclei for acoustic cavitation. In this study, we evaluated whether bubble nuclei form intracellularly or extracellularly in rat epithelial hepatoma (McA-RH7777) and musculoskeletal myoblast (L6) cell lines (n = 5 each), cultured in 3D using Matrigel™ scaffolds. A 3.68 MHz focused ultrasound transducer with f# = 1 was used to induce low-density cavitation using varying pulse lengths (10 to 100 μs) with pressures ranging up to p+ = 29 and p− = 12 MPa. The spatial location of the bubbles was monitored microscopically using high-speed photography at 20 000 fps. Despite significant radiation force on the cell scaffold, preliminary results show that acoustic cavitation bubbles (r = 20 μm approx.) preferentially form extracellularly near the cell membranes. This result suggests that the hydrophobicity in the amphipathic cell membrane may contribute to bubble nuclei formation. Future work includes investigating the distribution of bubble nuclei in healthy versus cancerous cell cultures. [Work supported by NSF CAREER 1943937.]

Performance analysis of OTFT with varying semiconductor film thickness for future flexible electronics

The goal of this study was to get a deeper understanding of the intricate impact of organic semiconductor thickness on the performance of devices, using a thorough and meticulous investigation at the microscopic level incorporating the density of defect model using using Silvaco ATLAS TCAD Simulator. The present work thoroughly investigates the relationship between the thickness of semiconductors and important performance parameters, such as hole concentration, electric potential, electric field, and Hole QFL. The comprehensive insights derived from this research not only enhance the comprehension of device physics but also provide a framework for the systematic enhancement of electronic devices. The widespread use of organic thin film transistors (OTFT) in future Flexible electronics, particularly in display and memory circuits, necessitates the incorporation of low voltage, high speed, and low cost characteristics.

Muscle Morphology Does Not Solely Determine Knee Flexion Weakness After Anterior Cruciate Ligament Reconstruction with a Semitendinosus Tendon Graft: A Combined Experimental and Computational Modeling Study.

The distal semitendinosus tendon is commonly harvested for anterior cruciate ligament reconstruction, inducing substantial morbidity at the knee. The aim of this study was to probe how morphological changes of the semitendinosus muscle after harvest of its distal tendon for anterior cruciate ligament reconstruction affects knee flexion strength and whether the knee flexor synergists can compensate for the knee flexion weakness. Ten participants 8-18months after anterior cruciate ligament reconstruction with an ipsilateral distal semitendinosus tendon autograft performed isometric knee flexion strength testing (15°, 45°, 60°, and 90°; 0° = knee extension) positioned prone on an isokinetic dynamometer. Morphological parameters extracted from magnetic resonance images were used to inform a musculoskeletal model. Knee flexion moments estimated by the model were then compared with those measured experimentally at each knee angle position. A statistically significant between-leg difference in experimentally-measured maximal isometric strength was found at 60° and 90°, but not 15° or 45°, of knee flexion. The musculoskeletal model matched the between-leg differences observed in experimental knee flexion moments at 15° and 45° but did not well estimate between-leg differences with a more flexed knee, particularly at 90°. Further, the knee flexor synergists could not physiologically compensate for weakness in deep knee flexion. These results suggest additional factors other than knee flexor muscle morphology play a role in knee flexion weakness following anterior cruciate ligament reconstruction with a distal semitendinosus tendon graft and thus more work at neural and microscopic levels is required for informing treatment and rehabilitation in this demographic.

Investigation of Li–Be and B halides as blanket in future fusion molten salt reactor

Abstract FLIBE (LiF–BeF2) is both a nuclear reactor coolant and a solvent for fertile or fissile materials. FLIBE can also dissolve a variety of fissile and fertile materials such as uranium, thorium and plutonium and has the ability to serve as liquid fuel for molten salt reactors (MSRs). It’s very high thermal capacity and chemical stability are among its other valuable properties. In addition, the low atomic weights of lithium, beryllium and to a lesser extent fluorine make FLIBE an effective neutron moderator. In this study, cross-section values were determined by using various level density models (constant temperature + Fermi gas, back-shifted Fermi gas, generalized superfluid, microscopic level density models) for reactions of 19F(n, α)16N, 19F(n, p)19O, 35Cl(n, α)32P, 35Cl(n, p)35S and 79Br(n, α)76As, 79Br(n, p)79Se, 127I(n, α)124Sb, 127I(n, p)127Te using TALYS 1.95 code and these datas are compared with the values in the EXFOR database.

High‐order models for hydro‐mechanical coupling problems in multiscale porous media

AbstractAn accurate prediction of nonlinear hydro‐mechanical (HM) coupling in subsurface structures with pronounced heterogeneity at multiple spatial scales is still an open topic and crucial for numerous engineering applications, for example, hydraulic fracturing and enhanced geothermal systems. In this study, novel high‐order multi‐scale asymptotic solutions are developed to accurately capture the locally oscillating characteristics of gas flow and solid displacement fields at multiple scales. First, the formal macro‐meso two‐scale asymptotic expansion is performed to establish the homogenized solutions and macro‐meso high‐order models which can predict the HM coupling problems at the macroscale and mesoscale. By directly expanding the cell functions defined at the mesoscale to the microscopic levels, the high‐order two‐scale expansion for the mesoscopic cell functions is built, and the upscaled relations for the flow parameters and constitutive coefficients from the microscale to the mesoscale and macroscale are developed correspondingly. The multi‐scale low/high‐order models are established by combining the high‐order expansion of all cell functions at the mesoscale and the developed macro‐meso two‐scale models. The main contributions are that the present approaches follow the reverse thought processes of reiteration homogenization methods, and offer a very innovative and efficient way to establish high‐accuracy high‐order models for the nonlinear HM coupling problems in the heterogeneous porous medium with any number of spatial scales. The effectiveness and accuracy of the present solution are validated by several representative cases with different constitutive coefficient contrasts. The results demonstrate that the high‐order solutions provide an accurate prediction for gas transport and solid deformation of heterogeneous porous media with multi‐scale configurations.

Development of Corrosion Resistant Welding Technology for Industrial Applications Study on the Impact of Material Variation and Welding Process

This article discusses the development of stainless welding technology aimed at improving corrosion resistance in industrial applications. The research focuses on the effect of material variation and welding process on the corrosion-resistant performance of welding joints. The research methodology includes the selection of materials with different compositions and the application of various welding techniques. Experiments were conducted to evaluate the microstructure, joint strength, and corrosion resistance properties of the weldments. The results show that material variation has a significant impact on the corrosion resistance of welding joints. The use of certain welding techniques can also affect the corrosion properties of the resulting material. Microstructure analysis provides an in-depth insight into the changes at the microscopic level that affect corrosion resistance. This study makes an important contribution in identifying critical parameters that need to be considered in the development of corrosion resistant welding technology to improve material performance in corrosive industrial environments. In conclusion, a better understanding of the relationship between material and welding process variations and corrosion resistance can help in designing more effective and durable welding technologies for industrial applications. This research has the potential to provide practical guidance for engineers and industry professionals in selecting optimal materials and welding techniques to address corrosion challenges in diverse work environments.

Molecular mechanism of efficient separation of isopropyl alcohol and isooctane by extractive distillation

In this paper, a method of extracting isopropyl alcohol and isooctane system from industrial wastewater of fuel oil by extractive distillation is proposed to realize resource utilization of waste and reduce environmental pollution. Isooctane and isopropyl alcohol are both products obtained from petroleum refining, which are widely used in many fields. In this study, the quantum chemical was used to determine that glycerol (Gl) and N, N-dimethylacetamide (DMAC) were the best extractants to separate Isopropanol and isopropyl alcohol. The intermolecular electrostatic interaction and reaction site between the extractant and the system were determined by electrostatic potential (ESP) analysis. Inter-complex compounds and weak interactions were analyzed by interaction region indicator (IRI). The independent gradient model based on Hirschfeld partition (IGMH) was used to visualize the electron density of the molecule. Meanwhile, the simulation process of azeotropic mixture separation of IPA and ISO by extractive distillation was established, and the process was optimized by a sequential iterative method. The economic and environmental were used to evaluate and analyze the process, and the azeotropic mixture separation was realized. Compared with Gl, the extractive distillation separation of isopropyl alcohol and isooctane by DMAC reduces the total annual cost by 5 %, energy consumption, and reduces the greenhouse gas emissions by 1 %, and has greater environmental protection and economic benefits. This work is guided by quantum chemical calculation and reveals the interaction mechanism of solvent separation azeotropic mixture from the microscopic level, which provides an important reference value for realizing high efficiency, energy saving, and green separation of azeotropic mixture in industry.

First report of Pyricularia oryzae the cause of blast disease in upland rice, in Lombok, West Nusa Tenggara

Rice (Oryza sativa L.) is a maincrop cultivated by farmers in Indonesia. The demand for rice has increased, but rice production has decreased due to attacks by plant pests, including pathogen blast disease. This research aims to (i) determine the symptoms of blast disease in upland rice in Lombok, (ii) determine the incidence of blast disease in upland rice in Lombok, (iii) and identify the pathogen that causes blast disease in upland rice in Lombok. The research was conducted in Lombok, West Nusa Tenggara. A sampling of rice crop tissue infected by blast disease was taken from 50 dryland locations in Lombok West Nusa Tenggara. From each point, three samples of rice crops with blast symptoms were taken to obtain 150 samples. Samples are then isolated and identified at the macroscopic, microscopic, and molecular levels. The study results showed that the macroscopic characteristics of rice leaves were rhombus-shaped and brown, and the pathogen produced white mycelium with a fine structure. In contrast, microscopic characteristics showed that the shape of the hyphae was septate, the structure of conidiophore with autophagic cell death, long pyriform microconidia, and long pyriform macroconidia. Based on 18S rRNA gene analysis, the Blast Lombok isolate had a DNA fragment of ±550bp. Based on these results, it can be concluded that the cause of blast disease in upland rice in Lombok, West Nusa Tenggara, is P. oryzae.

Insight into the evolution of membrane chemical degradation in proton exchange membrane fuel cells:From theoretical analysis to model developing

The chemical degradation of the proton exchange membrane (PEM) causes the changes in membrane properties and morphology, which directly affects the cell performance and membrane degradation. In this work, the changes of PEM during the chemical degradation are theoretically analyzed at both microscopic and mesoscopic levels. Based on the theoretical study, a bidirectionally coupled physical model of PEM fuel cell (PEMFC) performance and PEM chemical degradation is developed, which is used to investigate the evolutions of cell performance and chemical degradation. It can be found that the open circuit voltage first increases slightly and then decreases with time, and the ohmic loss increases rapidly under accelerated degradation conditions. The membrane chemical degradation is analyzed in terms of four aspects: the mass loss rate of the membrane, the region of pronounced degradation, the contribution of different degradation mechanisms and the proportion of ionomer species remaining. Furthermore, the effect of operating conditions on the degradation is examined. The degradation is most sensitive to voltage and has the fastest rate at high voltage, high temperature, high gas pressure and relative humidity of 60%. This work provides a deep insight into the PEM chemical degradation, which is instructive for the long-term prediction of PEMFC lifetime.

Effects of polyurethane/functionalised carbon nanotube interfacial interactions on tensile and compressive properties – molecular dynamics simulations

In order to understand the enhancement mechanism of the interaction between functionalised carbon nanotubes and polymer matrix, and to investigate the effects of different functionalised carbon nanotubes on the properties of composites at the microscopic level, the models of pure polyurethane (PUR), carbon nanotubes/polyurethane (CNTs/PUR), hydroxyl-functionalised carbon nanotubes/polyurethane (CNTOH/PUR), and carboxyl-functionalised carbon nanotubes/polyurethane (CNTCOOH/PUR) systems were constructed, and molecular dynamics methods were used to simulate the effects of different functionalised carbon nanotubes on the mechanical properties of polyurethane composite systems. The effects of different functionalised carbon nanotubes on the properties of PUR composite systems were compared by analysing the properties of PUR and its composite systems in terms of free volume fraction (FFV), radial distribution function (RDF), binding energy, and density distribution of PUR around different functionalised carbon nanotubes. The effects of intermolecular interactions on the properties of the composite systems were elucidated at the microscopic level. The final simulation results show that the CNTCOOH/PUR composite system with added carboxylated CNTs has the highest tensile yield strength, compressive properties and modulus; the smallest free volume fraction; the strongest bonding energy between CNTCOOH and PUR matrix, the largest density distribution of PUR matrix around CNTCOOH, and the best interfacial interaction.

Predicting nonradiative decay barrier of BODIPY dye in polar environment by applying ONIOM multiscale method

Fluorescent molecular sensors are widely used in biological research. They allow straightforward viscosity, temperature or polarity measurements at the microscopic level, including live cells. Maps of desired physical properties can be obtained by applying fluorescence lifetime imaging microscopy (FLIM) to cells. One of the most important properties of a cell is viscosity, as it affects other parameters, such as the rate of biochemical reactions and particle diffusion. Boron-dipyrromethene (BODIPY) compounds are widely used for viscosity measurements, but current variants have the undesirable sensitivity to polarity, and more suitable alternatives are being sought using theoretical computations. The polarizable continuum model (PCM) used in previous studies did not adequately take into account the influence of the polar environment when calculating the BODIPY activation energy associated with polarity sensitivity. After applying the multilayer ONIOM method in polar and non-polar environments, the calculated maximum wavelengths of the fluorescence spectra of the 8PhBODIPY compound were closer to the experimental results compared to PCM. The activation energy was also calculated, its value in polar and non-polar environments qualitatively corresponded to the experimental results, and the quantitative agreement was reached using the empirical correction.

Study on the Wetting Mechanisms of Different Coal Ranks Based on Molecular Dynamics

The exploration of coal wettability is not only of paramount significance in the mitigation of coal dust and the development of coalbed methane, but it also provides crucial technical support for realizing the geological storage of CO2 within the ‘dual-carbon’ background. Molecular simulation serves as an effective means by which to investigate coal wettability at the microscopic level. This study employed a molecular dynamics simulation to investigate the wettability of coal across 13 distinct coal ranks. Through the analysis of trajectory files, and the incorporation of experimental data during the modeling process, the mechanisms governing the evolution of wettability were revealed. The results demonstrated that the contact angle on the surface of coal increases with the elevation of coal rank. The molecule relative concentration analysis revealed that, with increasing coal rank, the overlap range between water droplets and the coal slab decreases, the height increases, and the diffusion degree of water molecules decreases, which are outcomes consistent with the results of the contact angle measurement. The contact angle was strongly correlated with the number of hydrogen bonds and secondarily correlated with the numbers of carbonyls, hydroxyls, and ether oxygens. The formation of hydrogen bonds was notably correlated with the number of hydroxyls, followed by that of ether oxygens, while its correlations with carbonyls and carboxyls were comparatively weaker. The contact angle exhibited positive correlations with vitrinite reflectance and carbon content, while showing negative correlations with oxygen content, H/C, and O/C. Additionally, it demonstrated positive associations with total sp2 carbon (fa), aromatic carbon (fa′), and non-protonated aromatic carbon (faN), and negative associations with aliphatic carbon (fal) and methylene carbon (falH). Understanding the variations in wettability among different coal ranks can provide a foundational model and theoretical basis for further exploration of the complex interactions among coal, gas, and water across various coal ranks.

Structural control of corneal transparency, refractive power and dynamics.

The cornea needs to be transparent to visible light and precisely curved to provide the correct refractive power. Both properties are governed by its structure. Corneal transparency arises from constructive interference of visible light due to the relatively ordered arrangement of collagen fibrils in the corneal stroma. The arrangement is controlled by the negatively charged proteoglycans surrounding the fibrils. Small changes in fibril organisation can be tolerated but larger changes cause light scattering. Corneal keratocytes do not scatter light because their refractive index matches that of the surrounding matrix. When activated, however, they become fibroblasts that have a lower refractive index. Modelling shows that this change in refractive index significantly increases light scatter. At the microscopic level, the corneal stroma has a lamellar structure, the parallel collagen fibrils within each lamella making a large angle with those of adjacent lamellae. X-ray scattering has shown that the lamellae have preferred orientations in the human cornea: inferior-superior and nasal-temporal in the central cornea and circumferential at the limbus. The directions at the centre of the cornea may help withstand the pull of the extraocular muscles whereas the pseudo-circular arrangement at the limbus supports the change in curvature between the cornea and sclera. Elastic fibres are also present; in the limbus they contain fibrillin microfibrils surrounding an elastin core, whereas at the centre of the cornea, they exist as thin bundles of fibrillin-rich microfibrils. We present a model based on the structure described above that may explain how the cornea withstands repeated pressure changes due to the ocular pulse.

Unveiling salinity-driven shifts in microbial community composition across compartments of naturally saline inland streams

Riverine environments host diverse microbial communities, exhibiting distinctive assemblies at both microscopic and macroscopic levels. Despite the complexity of microbial life in rivers, the underlying factors that shape the community structure across different compartments remain elusive. Herein, we characterized microbial community composition of biofilm and planktonic (water column) compartments in five naturally saline inland streams and a freshwater stream to examine changes in microbial communities following salinization via sequencing of the microbial 16S rRNA gene. Significant differences in specific conductivity, oxidation–reduction potential, dissolved oxygen, and pH among the sampled streams were measured, as were significant differences in the microbial community composition between the planktonic and biofilm. The bacterial families Bacillaceae, Vicinamibacterceae, and Micrococcaceae were significantly more abundant in the biofilm compartment, while Methylophilaceae, Alcaligenaceae, Spirosomaceae, Burkholderiaceae, and Comamonadaceae were more abundant in the planktonic compartment. In addition, salinity (based on specific conductivity) influenced the microbial community composition in both compartments, with higher sensitivity of the planktonic compartment. Increases in the bacterial families Shewanellaceae, Marinomonadaceae, and Saccharospirillaceae or loss of Anaeromyxobacteraceae could be indicative of increased salinity within inland streams. Our results suggest that monitoring of microbial assemblages of freshwater ecosystems could be used as early warning signs of increased salinization levels.