Lake Water Research Articles

Computer-aided design and construction of a novel electro-responsive ion-imprinted sensor for the individual/simultaneous detection of Cd(II) and Pb(II) in water environments.

A novel method for detecting Cd(II) and Pb(II) in water using composite ion-imprinted membranes (Cd@Pb-IIM/Ag@MOF@CHI) was developed. Pre-polymerization ratios were optimized via computer simulations and applied on Ag@MOF@CHI-modified electrodes using infrared light initiation. Characterization of the membranes through SEM and electrochemical methods revealed detailed morphology and composition. The sensor showed a dynamic linear response for Cd(II) and Pb(II) concentrations ranging from 1.1×10-9 to 1.2×10-6molL-1, with a detection limit of 1.0×10-10molL-1. In samples with various non-target ions, the sensor exhibited high selectivity, attributed to the optimal coordination ratio (Cd(II): Pb(II): PAR=1:1:3). Successful tests were conducted in tap, lake, and river water, highlighting its potential for environmental monitoring.

A novel electrochemical sensor based on La-MOF@C60-β-cyclodextrin composite for sensitive detection of dichlorophen in lake and tap water

A novel electrochemical sensor based on La-MOF@C60-β-cyclodextrin composite for sensitive detection of dichlorophen in lake and tap water

Simultaneous detection and quantification of ciprofloxacin, doxycycline, and levofloxacin in municipal lake water via deep learning analysis of complex Raman spectra

Simultaneous detection and quantification of ciprofloxacin, doxycycline, and levofloxacin in municipal lake water via deep learning analysis of complex Raman spectra

Covalent organic frameworks with nitrogen-rich triazine units and suitable pore size for highly efficient adsorption and sensitive detection of bisphenols in water.

Herein, using 1,3,5-triformylphloroglucinol (Tp) and 4,4',4″-(1,3,5-triazine-2,4,6-triyl) tris(1,1'-biphenyl) trianiline (Ttba) as ligands, nitrogen-rich triazine unit-based covalent organic frameworks (COFs) with a suitable pore size, named TpTtba-COFs, were synthesized, and they were employed as adsorbents for the extraction and detection of three bisphenols (BPs)-BP A (BPA), BP B (BPB), and BP S (BPS)-in water. Using 2,4,6-tris(4-aminophenyl)-1,3,5-triazine (Tapt) and 1,3,5-tris(4-aminophenyl)benzene (Tapb) ligands as substitutes for Ttba, nitrogen-rich triazine unit-based COFs with a smaller pore size and nitrogen-poor triazine unit-based COFs, named TpTapt-COFs and TpTapb-COFs, respectively, were also prepared for comparison. The adsorption performances of the three COF adsorbents with regard to the three BPs were tested. Owing to nitrogen-rich triazine units and a pore size suitable for BP adsorption, the maximum adsorption capacities of TpTtba-COFs for BPA, BPB, and BPS were 1.13, 1.33, and 1.37 times those of TpTapt-COFs and 2.10, 2.27, and 1.92 times those of TpTapb-COFs, respectively. The adsorption behavior and possible adsorption mechanism of the BPs on the TpTtba-COFs were also investigated. In addition, a TpTtba-COF-based dispersive solid-phase extraction-high-performance liquid chromatography/ultraviolet method exhibited an excellent linear range (1-800 ng/mL) and satisfactory limit of detection values (0.20-0.32 ng/mL) for the three BPs. The spiked recoveries of the three BPs in river and lake water ranged within 81.9%-101.9% and 82.8%-100.8%, respectively. Overall, this study offers valuable insights into the rational design of adsorbents for adsorption and sensitive detection of BPs in environmental water.

Studying Cationic Liposomes for Quick, Simple, and Effective Nucleic Acid Preconcentration and Isolation.

To ensure high quality of food and water, the identification of traces of pathogens is mandatory. Rapid nucleic acid-based tests shorten traditional detection times while maintaining low detection limits. Challenging is the loss of nucleic acids during necessary purification processes, since elution off solid surfaces is not efficient. We therefore propose the development of a vanishing surface strategy in which cationic liposomes efficiently capture nucleic acids. A lipoplex is formed that can be easily centrifuged down and washed if needed. Adding the lipoplex to detergent solutions or nucleic acid amplification reactions dissolves the liposomes, releasing 100% of the nucleic acid into the reaction. After initial protocol optimization, it was applied to isolate DNA from Escherichia coli, Staphylococcus aureus, and adenovirus in buffer followed by qPCR detection. This enabled the detection of these pathogens down to concentrations of 1 CFU or 1 PFU/mL, respectively. Comparing it to a standard commercial DNA extraction kit, it was superior, as evidenced by lower Ct-values in the qPCR for all pathogen concentrations. Scaling up to larger volumes, samples containing bacteria were first concentrated through nitrocellulose filters (pore size = 0.45 μm). Tap water, lake water, and rinse water of fresh produce were investigated, leading to relevant limits of detection of 100 CFU in 100 mL of tap water, 1000 CFU in 100 mL of lake water, and 100 CFU in 10 g of iceberg lettuce, respectively. Since the liposome protocol is a homogeneous, simple incubation step, it is a valuable alternative to standard commercial nucleic acid extraction kits.

Mercury patterns in lakes within a natural hotspot in the Southern Volcanic Zone of the Andes (Nahuel Huapi National Park, Patagonia, South America)

Environmental context The pristine oligotrophic lakes of Andean Patagonia are influenced by volcanic eruptions and atmospheric deposition. This study focuses on mercury (Hg) dynamics in two connected lakes in a natural Hg hotspot of the southern Andes. The lake waters have low dissolved organic carbon and moderate to high Hg concentrations, resulting in high Hg availability. These promote Hg binding to natural particulates, thereby favouring its incorporation into food webs. Rationale Mercury hotspots have been identified in pristine volcanic areas of the northern Patagonian Andes (South America). In this study, we investigated spatial and seasonal patterns of total mercury (THg) in two oligotrophic lakes in Nahuel Huapi National Park (Argentina), adjacent to the Puyehue Cordón Caulle volcanic complex (Chile). We hypothesise that THg levels in the lakes are linked to seasonal terrestrial inputs and that in-lake processes influence its distribution and availability. Methodology Water samples were collected seasonally in the connected lakes Pire (shallow) and Brazo Rincón branch of L. Nahuel Huapi (BR, deep). The concentration of THg was studied together with physicochemical variables, including the concentration and quality of dissolved organic matter (DOM). THg was measured by cold vapour atomic fluorescence spectrometry (CVAF) and DOM was characterised through absorbtion and fluorescence spectroscopy. Results Lakes showed moderate to high THg concentrations and remarkable Hg availability. THg increased downwards in the landscape and was associated with DOM terrestrial prints, indicating its co-transport from the catchment during high connectivity periods (from winter to early summer). In summer, THg levels were associated with higher mineralisation (higher dissolved inorganic carbon, DIC) and diffusion from sediments, especially in the shallow lake. THg availability and distribution were related to the quality of the DOM pool and the total suspended solids (TSS) year round. The high biotic contribution to TSS (higher chlorophyll-a:TSS) in BR indicated Hg binding to phytoplankton and incorporation into lake food webs. Discussion Pristine oligotrophic lakes influenced by natural Hg sources have a high potential for Hg accumulation in food webs because their typically high Hg and low DOC concentrations result in high Hg availability, promoting Hg binding to abiotic and biotic particles.

Indigenous Owned Aquatic Monitoring Programs in the Inuvialuit Settlement Region Work: An Adaptive Framework with example Traditional & Local Knowledge Quotes and Coastal Marine Water Quality Data Collected from 2019 to 2022 near Sachs Harbour and Ulukhaktok

Canadian Arctic residents are experiencing longer open water seasons and observing significant change in aquatic species and habitats. Rapid ecosystem change threatens Inuit people’s food security and adds to existing generational trauma caused by ongoing colonialism and industrialization. Indigenous owned environmental monitoring programs prioritize safety, support community empowerment and self-determination to increase the understanding of and resilience to the impacts of this human caused global climate crisis. To this end, in 2019 local expert fishers and hunters from the Inuvialuit Settlement Region worked collaboratively with an independent research scientist to start up community owned aquatic monitoring and observation (AMO) programs in Sachs Harbour and Ulukhaktok in the Inuvialuit Settlement Region. The field teams received training to collect year-round data of lake and coastal water quality data using scientific instruments that measure water temperature, conductivity/salinity, turbidity and dissolved oxygen with depth from the surface down to 150 meters. ROV’s, drones and hydrophones extend observations and Traditional & Local Knowledge (TLK) directs the programs. External clients can hire the teams to augment core funding. AMO teams are finalizing their program and data ownership protocols, which are informed by the Canadian UNDRIP Act and OCAP® principles. Indigenous owned, directed and operated environmental monitoring programs justly deserve funding priority and ongoing public support to help conserve and protect critical areas for future generations.

Lake level fluctuation controls the formation, types, and abundance of coated grains in hypersaline lakes: a case study from Urmia Lake (NW Iran)

ABSTRACTThe hypersaline Urmia Lake in NW Iran offers unique sedimentary environments sensitive to climate and environmental shifts, fostering coated grain formation and serving as a vital indicator of paleoenvironmental conditions. This study characterizes coated grains within a 25‐m sediment core dating back to ~50 cal ka bp, assessing their significance through morphology, internal structures, mineralogy, and geochemistry. Coated grains in Urmia Lake exhibit concentric laminations, primarily calcite and aragonite, revealing alternating light carbonate‐rich and dark organic‐rich laminations. These reflect seasonal and long‐term variations in water chemistry and biogenic production. Dry season algal blooms contribute to lamination, highlighting the interplay between seasonal climate fluctuations and the consequent lake water enrichment in calcium, carbonate, and bicarbonate ions. The diversity and abundance of coated grains indicate three main lake level fluctuation stages in the last ~50 cal ka: a lowering stage with dominant coated grains, a low lake level with dominant terrigenous fragments and minerals, and a high lake level with prominent Artemia urmiana fecal pellets. The role of the brine shrimp A. urmiana in coated grain formation involves absorbing calcium, carbonate, and bicarbonate ions and inhibiting coated grain formation during high lake levels while providing nuclei during lake lowering. An in‐depth investigation of coated grains provides a chemical and biological formation framework, highlighting three main episodes in the lake's history.

A sensitive determination of lead by hydride generation integrated with micro-sampling gas–liquid separator-FAAS after preconcentration by NiFe2O4 nanoparticles

In the present study, dispersive solid phase extraction – hydride generation integrated with micro–sampling gas–liquid separator – flame atomic absorption spectrometry was proposed to determine lead in lake water samples taken in the Horseshoe Island, Antarctica. In scope of this study, microwave assisted NiFe2O4 nanoparticles were synthesized, and the characterization of nanoparticles were carried out by FT-IR, XRD and SEM. All influential parameters of dispersive solid phase extraction and hydride generation were optimized to enhance signal intensity belonging to the analyte. System analytical performance studies were performed, and limit of detection and limit of quantitation were calculated as 2.16 µg kg–1 and 7.19 µg kg–1, respectively. Recovery studies were conducted to the spiked lake water samples and two different calibration strategies were applied. Percent recovery results were calculated between 102.0 and 169.5% by external calibration strategy while matrix matching calibration strategy provided recovery results in the range of 78.8–142.9%.

Examination of heavy metal concentrations and their interaction with anthropogenic sources in Ermenek Dam Lake (Turquoise Lake)

This study aims to determine the spatial distribution of heavy metal pollution in Ermenek Dam Lake, water quality assessment and pollution sources. For this purpose, samples were taken 6 times a year from 12 points determined in 2024. Physico-chemical parameters and heavy metals were analyzed in the study. Using the analysis results, indexes such as Water Quality Index and Heavy Metal Pollution Index were calculated. The results show that the lake water complies with TS 266 and WHO standards. The index results indicate that the lake water is at low pollution and risk level and is safe. The distribution and sources of heavy metals were examined using correlation analysis, Principal Component Analysis and Hierarchical Cluster Analysis. Correlation analyses showed that there were significant relationships between pH, temperature, conductivity, dissolved oxygen and TDS and heavy metals. PCA results revealed that Zn was positively correlated with temperature and pH, while Mn and Ni were inversely correlated. The alignment of Pb, Cu and Cd in the same direction showed that these parameters were affected by common sources. HCA results showed that Cr and Fe have similar transport and source properties, while Mn and Ni are affected by different sources. In general, it was determined that heavy metal pollution in lake water was at low levels and local concentrations were present. The study revealed the effects of anthropogenic activities on the lake ecosystem. The findings of the study provide a guiding basis for water quality management in similar hydrological systems.Graphical abstract

From invasive species to agricultural resource: evaluation of Phragmites australis from Zarivar Lake as an organic amendment for the release of phosphorus, potassium, micronutrients and toxic metals

Overgrowth of Phragmites australis has become a serious issue for Zarivar Lakes and many water bodies worldwide. The objective of this research was to use the harvested common reed as a soil organic amendment. For this purpose, the release kinetics of phosphorus and potassium from Phragmites a. biomass were studied. This study was conducted as a split-plot design with two treatments including a control and 3% (w/w) Phragmites a. and eight incubation durations (7, 14, 28, 42, 56, 70, 84, 98 days) in a fully randomized design with three replications. After 98 days, the amount of cumulative phosphorus released increased from 12.4 to 127.3 mg/kg in the control treatment and from 18.9 to 150.1 mg/kg in the 3% (w/w) treatment, while potassium released increased from 269.6 to 2206.1 mg/kg in the control treatment and from 322.2 to 2584.3 mg/kg in the 3% treatment. The release intensity (b) of phosphorus was larger than that of potassium in the exponential equation, and the release of the elements was a diffusion function in the parabolic equation. In the Phragmites a., dominant functional groups (C-H) and (C = O) were reported. The surface of the plant was smooth and dense. The results showed that the Phragmites a. can be a source of phosphorus and potassium and does not cause heavy metal pollution to the soil and exponential and parabolic equations had the highest correlation with the release of elements. Phragmites a. can be used as an environment-friendly organic amendment, however, additional research is needed.

Evaluation of nutrient loads conveyed to the deep subalpine lakes of Northern Italy through their main tributaries

Nutrient pollution is a critical issue for lakes, leading to cultural eutrophication, which damages the ecosystem and prevents water uses. Proper watershed management practices must be put into action to effectively oppose eutrophication. Because of the complexities and the multiple layers of stakeholders involved in this process, the only factual way to evaluate improvements in watershed nutrient management is to directly estimate nutrient loads at watershed closing sections through available data from environmental monitoring. The Italian deep subalpine lakes (DSLs: Lake Como, Lake Garda, Lake Idro, Lake Iseo, Lake Maggiore) suffered from extensive eutrophication from the 1950s to the early 1980s. Their water quality improved in the 1980s and 1990s after national regulations were introduced to address nutrient pollution. After the turn of the century, increasingly pressing limits on nutrient disposal have been issued, yet steady if not worsening lake water quality conditions have been observed overall. To shed light on the issue, quantifying present and past external loads to these lakes based on direct measurements is essential. In this work, we focused on the main tributaries of the Italian DSLs, employing the observed time series of flowrate and nutrient concentrations to estimate the loading levels of nitrogen and phosphorus and their temporal evolution over a period ranging between 13 and 42 years according to data availability. The LOAD ESTimator (LOADEST) software was adopted to support the load quantification process. Results show that a general decrease in external nutrient loads is still occurring, albeit at a slow pace, the fastest reduction occurring for the Oglio River flowing into Lake Iseo, which has suffered from severe nutrient pollution till recently. Increasing loads have conversely been identified for the Sarca River flowing into Lake Garda. These outcomes highlight the beneficial actions carried out to reduce nutrient pollution, although a decorrelation analysis between external loads and flowrate is suggested for a clearer evaluation of its evolution across the DSLs.

Seasonal lake‐to‐air temperature transfer functions derived from an analysis of 1395 modern lakes: A tool for reconstructing air temperature from proxy‐derived lake water temperature

AbstractLacustrine palaeotemperature reconstructions are important for characterising past temperature and hydroclimate change, validating multi‐proxy reconstructions and evaluating global climate models. In particular, lake water temperature is often derived from geochemical proxies—including clumped isotopes (Δ47), oxygen isotopes (δ18O), alkenone lipids (Uk’37) and GDGT compounds (TEX86). However, global climate models, constrained by resolution, computational demand and cost, are designed to simulate large‐scale processes, often at the expense of resolving lakes and simulating lake temperature. Consequently, this limitation complicates the comparison of climate model‐simulated variables such as air temperature, with lake water temperature or with other proxy variables (e.g. pollen‐derived air temperature), and requires the use of a transfer function to relate lake temperature to air temperature. Previous work developed transfer functions to translate proxy‐derived seasonal lake water temperature to mean annual air temperature using ground‐based measurements from 88 lakes. This study reports new lake‐to‐air temperature transfer functions (for annual, spring through summer, spring, summer and warmest month) that incorporate lake surface water temperature, and new variables including latitude and elevation, by analysing climate reanalysis data and long‐term satellite observations of surface temperatures for 1395 modern lakes via regression‐based inverse modelling. With the use of multiple regression models and a dataset roughly 10 times larger, the error in predictions of mean annual air temperature is reduced by up to 48% compared to previous work. To demonstrate the potential of the new transfer functions for integrating and comparing proxy data with model output, Pliocene and Pleistocene mean annual air temperature was reconstructed from Δ47‐derived lake temperatures and compared with model simulations for the Last Glacial Maximum and mid‐Piacenzian warm period. The new transfer functions, with reduced error, should enable more accurate palaeotemperature reconstructions from proxy‐derived lake water temperature and allow for more comprehensive assessments of climate model skill.

Construction of novel hyper-crosslinked polymers with adjustable hydrophilicity for efficient extraction of nitroimidazoles.

To effectively control food safety risks caused by nitroimidazoles (NDZs), a sensitive detection method was established on the basis of a newly-developed solid-phase extraction (SPE) sorbent named as Phl-TBM that is a porous polymer prepared by crosslinking natural phloretin with (2,4,6-tris(bromomethyl)mesitylene. The Phl-TBM presented outstanding NDZs adsorption capacity, which can be ascribed to its well-developed porosity and multiple hydrogen bonding sites. With Phl-TBM as SPE sorbent, NDZs were successfully isolated and enriched from lake water, Basa fish, and beef before being assayed by high-performance liquid chromatography-diode array detector. This Phl-TBM based method has a detection limit of 0.02-0.06 ng mL-1 in lake water, 0.60-1.50 ng g-1 in Basa fish, and 0.70-1.20 ng g-1 in beef. The method recoveries are 80.0-120 % with relative standard deviations less than 8.1 %. This study presents an effective and feasible approach for detection of NDZs residues at trace level.

Bimetallic metal-organic frameworks as electrode modifiers for enhanced electrochemical sensing of chloramphenicol.

Anelectrochemical sensor is presentedfor the detection of the chloramphenicol (CAP) based on a bimetallic MIL-101(Fe/Co) MOF electrocatalyst. The MIL-101(Fe/Co) was prepared by utilizing mixed-valence Fe (III) and Co (II) as metal nodes and terephthalic acid as ligands with a simple hydrothermal method and characterized by SEM, TEM, XRD, FTIR, and XPS. Electrochemical measurements such as electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and differential pulse voltammetry (DPV) showed that bimetallic MIL-101(Fe/Co) had the faster electron transfer, larger electroactive area, and higher electrocatalytic activity compared with their monometallic counterparts due to the strong synergistic effect between bimetals. Inspired by these results, the MIL-101(Fe/Co)-based sensor was used to detect CAP. Some experiment parameters of pH, Fe and Co molar ratio, MIL-101(Fe/Co) volume, and DPV quiet time were optimized. The direct reduction mechanism of CAP was verified to involve four electrons and four protons process. Finally, the sensitive and selective CAP detection in the concentration range 1 to 200μM with a detection limit of 0.3μM was realized by the proposed sensor. The satisfactory recoveries in tap water and lake water indicated the practicability of the proposed electrochemical sensor. It is expected that this work may open up a paradigm for the preparation of MOF-based electrode modifiers with desired electrocatalytic performance for environmental pollution monitoring.

Disruption of boreal lake circulation in response to mid-Holocene warmth; evidence from the varved sediments of Lake Nautajärvi, southern Finland.

Future climate projections are expected to have a substantial impact on boreal lake circulation regimes. Understanding lake sensitivity to warmer climates is therefore critical for mitigating potential ecological and societal impacts. The Holocene Thermal Maximum (HTM; ca 7-5ka BP) provides a valuable analogue to investigate lake responses to warmer climates devoid of major anthropogenic influences. Here, we analyse the micro-X-ray core scanning profiles (μ-XRF) of the annually laminated (varved) sediments from Lake Nautajärvi (NAU-23) in southern Finland to elucidate changes in lake circulation and sedimentation patterns. Principal component analysis (PCA) identifies two key components in the geochemical data associated with the nature of the sediments, i.e. detrital vs organic sedimentation (PC1), and hypolimnetic oxidation (PC2). Our findings reveal that during the HTM, the lake became more sensitive to changes in oxygenation and mixing intensity. These changes were triggered by a warmer climate, which increased organic matter and redox sensitive metal solute concentrations in the water column, strengthening lake stratification and weakening dimictic circulation patterns. Superimposed on HTM weakened circulation are distinct phases of increased oxidation and iron-rich varve formation that do not happen when the background conditions are cooler (i.e. the early and late Holocene). This is driven by temporary strengthening of the mixing regime in response to climatic variability and storminess cycles across southern Scandinavia. These findings demonstrate that whilst warmer conditions weaken boreal lake circulation regimes, they can also make them increasingly vulnerable to short term oscillations in prevalent climatic conditions and weather patterns, which could have significant impacts on lake water quality and aquatic ecosystems. These findings underscore the non-stationary nature of lake sensitivity to short-term climatic variability and emphasize the potential for similar shifts to occur under future warming scenarios.

A multimedia fugacity model for assessing the environmental fate of typical antibiotics in Lake Taihu with emphasis on the biomechanical characteristics of drug delivery systems

The extensive use of antibiotics in the Taihu Lake Basin has led to a significant threat to human and environmental health. In this context, the QWASI model is developed to simulate the fate of typical antibiotics in Lake Taihu. Through this model, real-time tracking of the dynamic changes in antibiotic content is possible. The study primarily focuses on evaluating the fate and transfer of antibiotics in the water and sediment phases of the lake. The model results indicate that most of the simulated concentrations and mass fluxes are within the same order of magnitude as the measured values, demonstrating a good simulation effect. However, an underestimation of the simulated output value occurs in some cases. The sediment layer serves as the main accumulation site for antibiotics, and the mass balance equation is a crucial tool for simulating the environmental distribution of antibiotics. Sulfamethoxazole (SMX) exhibits a relatively high concentration in water due to its large model input. The sensitivity analysis reveals that for ATM, SMX, and OFX, the five input parameters with the most significant impact are the half-life in water, sediment-water partition coefficient, sediment solids concentration, sediment particle density, and sediment-water diffusion MTC. For OTC, the impact of lake water depth is more prominent than the sediment-water mass transfer rate. The uncertainty analysis effectively showcases the model’s stability, with the water phase concentration showing better stability. In this process, each factor is assigned a correlation coefficient to represent its influence on the original content. The sediment phase antibiotic concentration has a relatively high uncertainty. The source intensity assessment in this study utilizes direct monitoring data of the Taihu Lake water body, ensuring higher accuracy. The major factor contributing to prediction errors is the ambiguity of the sediment phase, which is affected by numerous environmental factors. Importantly, when considering the fate of antibiotics in the lake, the biomechanical characteristics of potential drug delivery systems play a vital role. The movement and dispersion of antibiotics within the water and sediment are influenced by biomechanical forces. In the sediment, the porosity and permeability, which are related to biomechanical properties, can determine the rate at which antibiotics penetrate and accumulate. Understanding these biomechanical aspects of drug delivery systems can help in devising more effective strategies for antibiotic remediation. It can also provide insights into how the physical environment interacts with the chemical behavior of antibiotics, ultimately contributing to a more comprehensive understanding of the environmental fate of antibiotics in Lake Taihu. This is the first study to explore the fate of antibiotics in Lake Taihu and offers valuable recommendations for the restoration of antibiotic-contaminated lakes. It enriches the research perspectives on water management, especially in relation to addressing water pollution caused by antibiotic abuse.

Sensitivity-enhanced hydrogel digital RT-LAMP with in situ enrichment and interfacial reaction for norovirus quantification in food and water.

Low levels of human norovirus (HuNoV) in food and environment present challenges for nucleic acid detection. This study reported an evaporation-enhanced hydrogel digital reverse transcription loop-mediated isothermal amplification (HD RT-LAMP) with interfacial enzymatic reaction for sensitive HuNoV quantification in food and water. By drying samples on a chamber array chip, HuNoV particles were enriched in situ. The interfacial amplification of nucleic acid at the hydrogel-chip interface was triggered after coating HD RT-LAMP system. Nanoconfined spaces in hydrogels provided a simple and rapid "digital format" to quantify single virus within 15 min. Through in situ evaporation for enrichment, the sensitivity level was increased by 20 times. The universality of the sensitivity-enhanced assay was also verified using other bacteria and virus. Furthermore, a deep learning model and smartphone app were developed for automatic amplicon analysis. Multiple actual samples, including 3 lake waters, strawberry, tap water and drinking water, were in situ enriched and detected for norovirus quantification using the chamber arrays. Therefore, the sensitivity-enhanced HD RT-LAMP is an efficient assay for testing biological hazards in food safety monitoring and environmental surveillance.

Effectiveness of agricultural BMPs on phosphorus load reduction for the Canadian Lake Erie basin: A literature review

Lake Erie, the shallowest and warmest of the Great Lakes, has been increasingly threatened by eutrophication and harmful algal blooms affecting economic growth in the region. Excess nutrients, particularly phosphorus, transported with agricultural runoffs have become a major issue of lake water quality. In response to this growing concern over the adverse environmental effects of agriculture, farmers, conservation authorities and governments have worked together to promote and implement best or beneficial management practices (BMPs) in the contributing watersheds that focus on maintaining agricultural activity and farm profitability while protecting the environment. This paper conducted a technical review of BMPs and their effectiveness on phosphorus load reduction from agricultural fields for the Canadian Lake Erie Basin (CLEB). These BMPs include cover crop, conservation tillage, manure incorporation, crop nutrient planning, fragile land retirement, adding organic amendments, reducing soil compaction, controlled tile drain, grassed waterway, vegetative filter strip, riparian buffer, water and sediment control basin, and wetland restoration. Field experiments and modeling studies about BMP effectiveness on phosphorus load reduction from agricultural fields in the CLEB and the Great Lakes region were reviewed and assessed. Findings from other similar geographic regions were also documented for comparison and reference. Because BMPs are site-specific, their phosphorus load reduction effectiveness varied over a wide range in the literature depending upon characteristics of the BMP and local climate, slope, soil type, land use, and land management conditions. Based on the literature review, factors influencing BMP effectiveness were analyzed, and suggestions on research priorities for evaluating BMP effectiveness in the CLEB were provided. This study will benefit decision-makers, watershed conservation authorities, and other stakeholders in estimating phosphorus load reductions from agricultural landscapes and contribute to tracking progress toward achieving Canada’s phosphorus load reduction targets for Lake Erie.

Abrupt transformation of West Greenland lakes following compound climate extremes associated with atmospheric rivers

Arctic ecosystems are affected by accelerated warming as well as the intensification of the hydrologic cycle, yet understanding of the impacts of compound climate extremes (e.g., simultaneous extreme heat and rainfall) remains limited, despite their high potential to alter ecosystems. Here, we show that the aquatic ecosystems in historically arid west Greenland have undergone an ecological transformation after a series of atmospheric rivers that simultaneously produced record heat and rainfall hit the region in autumn 2022. We analyzed a unique, long-term lake dataset and found that compound climate extremes pushed Arctic lakes across a tipping point. As terrestrial-aquatic linkages were strengthened, lakes synchronously transformed from "blue" lakes with high transparency and low pelagic primary production to "brown" in less than a year, owing to a large influx of dissolved organic material and metals, with iron concentrations increasing by more than two orders of magnitude. The browning of lake waters reduced light penetration by 50% across lakes. The resulting light limitation altered plankton distributions and community structure, including a major reduction in prokaryotic diversity and an increase in algal groups capable of metabolizing organic carbon sources. As a result, lakes shifted from being summer carbon sinks to sources, with a >350% increase in carbon dioxide flux from lakes to the atmosphere. The remarkably rapid, coherent transformation of these Arctic ecosystems underscores the synergistic and unpredictable impacts of compound extreme events and the importance of their seasonal timing, especially in regions with negative moisture balance.