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Crop reference evapotranspiration (ET0), which connects the energy and water balance, is an important indicator used in water resource management and agricultural production. On the basis of daily meteorological data from 479 observation stations, we investigate changes in ET0 and associated climate factors across the main grain‐producing area (MGPA) of China from 1960 to 2015. The Mann–Kendall test and Sen's slope estimator were applied to detect trends in ET0, and regression analyses and composite analyses were used to evaluate the contributions of climatic variables and large‐scale anomalies that may affect ET0. The results of this study show that ET0 in the MGPA decreased (−2.67 mm/decade) during summer throughout the past 56 years, and that this change is largely attributable to decreased sunshine duration and wind speed (WS). Furthermore, decreased WSs in the 850‐hpa geostrophic wind field, are responsible for decreases in ET0 in Northeast China Region (−1.85 mm/decade), which affect ET0 by significantly weakening the observed surface WS. Meanwhile, significant low cloud cover variations accounted for the decrease in ET0 in the Huang‐Huai‐Hai Region (−7.85 mm/decade), Loess Plateau Region (−2.91 mm/decade), Yangtze River Region (−3.96 mm/decade), and Southwest China Region (−2.71 mm/decade). However, decreases in the integrated atmospheric water vapour content (IWVC), which act to weaken the surface relative humidity, are hypothesised to increase ET0 in the South China Region (1.25 mm/decade). Topographic map of China with 479 meteorological stations across main grain‐producing area (MGPA). [ABSTRACT FROM AUTHOR]

ABSTRACT This research analyses the long-term changes in the precipitation structure over the karst area of southwest China, as recorded by 153 national meteorological stations from 1959 to 2009. Study results are as follows: (1) The karst area of southwest China is categorized into six similar precipitation clusters, including two low-rainfall clusters located in the western and northern areas and four high-rainfall clusters distributed in the eastern and southern areas. (2) Although the decreasing trend of annual total precipitation is weak, autumn precipitation decreases significantly over the whole study area. The autumn total precipitation decreases significantly at 51% of the stations because the autumn wind and water vapor flux of the study area gradually decreased, and the autumn low-latitude and mid-latitude sea surface temperature ( SST) of East Asia continues to rise and gradually leads to positive sea anomalies. (3) The number of rainy days decreases at 85.6% of the stations, especially in the central and southeastern regions of the area. Consequently, almost 53% of the total stations are characterized by an increasing precipitation intensity. (4) The occurrence time of the accumulated percentage precipitation in the western mountain areas is usually later than that in the eastern coastal areas, and the occurrence date of accumulated percentage precipitation ( DAP) seems to occur increasingly earlier over the whole study area. (5) Light rain occurs more frequently (76% of annual total rainy days) and contributes 25% to annual total precipitation, whereas although heavy rains such as storms occur less frequently at 3% of annual total rainy days, it contributes almost 19% to annual total precipitation. (6) The occurrence and contribution of wet periods ( WPs) decrease with an increase in their duration. WPs with short durations (e.g. 1-4 days) tend to be the predominant precipitation events. [ABSTRACT FROM AUTHOR]

At present, in the directed energy deposition (DED) of metals, the heat transfer of the melt pool and microstructural evolution are not fully understood. This study investigates the thermal effect on the microstructure and the mechanical properties of DED AISI 316L, using in situ optical monitoring. Five thin-wall samples were tested to determine the effect on microstructural evolution and mechanical properties with variable laser powers and scanning speeds. A comprehensive optical monitoring system with a CMOS (coaxial complementary metal oxide semiconductor) visual module and an infrared camera was adopted in analyzing the temperature gradient and the solidification rate. The emissivity of the melt pool was calibrated, using the melt pool length, extracted from the coaxial visual image. The results showed that microstructures mainly consist of the coarse columnar grain and the equiaxed grain at the top layer of AISI 316L samples. The direction of epitaxial growth of columnar grains is affected by the compromise between directional heat flux and crystallographic direction. High numerical temperature gradient and high solidification rate are beneficial to obtaining fine grain size and high yield stress. A modified microstructure map for DED AISI316L was established, which correlates the solidification parameters with a solidification microstructure. This research study, combining temperature distribution, solidification parameter, microstructure, and tensile property, provides an experimental identification of solidification parameters and the model on the solidification theory for precision control of DED process. [ABSTRACT FROM AUTHOR]

• Coal chemical components and structures affected by acidification and THF are studied. • Effect of successive treatments of acidification and THF on pore fractal features is analyzed. • Relationship between SSA, average pore size and fractal parameters are discussed. • Successive treatments of acidification and THF could well improve pore development. Chemical solvents could change coal components and effectively enhance conductivity of coal reservoir, which is beneficial to efficient methane extraction. Relationship between coal chemical structure parameters and main functional groups variations affected by acidification and tetrahydrofuran (THF) is investigated through infrared spectroscopy tests and curve peak fitting. Meanwhile, variations in fractal dimensionality and pore structure characteristics are studied by adopting low-temperature nitrogen adsorption tests and Frenkel-Halsey-Hill (FHH) fractal model. Main results are: (1) After extracting raw coal and acidified coal using THF with varying concentrations, absorbance of aromatic hydrocarbon –CH surface and aromatic methyl bond become weaker. While the proportion of substituted aromatic hydrocarbons increases in acidified coal than in raw coal. Acidification treatment could reduce strength of C-O-C absorption peak. Proportion of CH 2 and CH 3 in raw coal decreases with increasing THF concentration, indicating that THF could react with aliphatic structure to reduce CH 2 and CH 3 content. Extraction with THF dissolves aromatic structure, lowering C = C content in coal to different degrees. (2) Acidification pretreatment could produce more micropores in coal samples. Micropore contents of acidified coal after THF extraction are all lower than coal sample S, while transition pores and mesopores contents are both higher than those in coal sample S. (3) Fractal dimension D 1 of raw coal indicates a relatively linear relationship with specific surface area, while the D 1 of acidified coal is less correlated with specific surface area. The factor D 2 shows a linear relationship with average pore size. After treatment of THF, average pore size of raw coal increases with D 2 , while that of acidified coal varies in different degrees with uneven distribution of pore sizes. [ABSTRACT FROM AUTHOR]

Microbial source tracking (MST) technology represents an innovative approach employed to trace fecal contamination in environmental water systems. The performance of primers may be affected by amplification techniques, target primer categories, and regional differences. To investigate the influence of these factors on primer recognition performance, a meta-analysis was conducted on the application of MST in water environments using three databases: Web of Science, Scopus, and PubMed (n = 2291). After data screening, 46 studies were included in the final analysis. The investigation encompassed Polymerase Chain Reaction (PCR)/quantitative PCR (qPCR) methodologies, dye-based (SYBR)/probe-based (TaqMan) techniques, and geographical differences of a human host-specific (HF183) primer and other 21 additional primers. The results indicated that the primers analyzed were capable of differentiating host specificity to a certain degree. Nonetheless, by comparing sensitivity and specificity outcomes, it was observed that virus-based primers exhibited superior specificity and recognition capacity, as well as a stronger correlation with human pathogenicity in water environments compared to bacteria-based primers. This finding highlights an important direction for future advancements. Moreover, within the same category, qPCR did not demonstrate significant benefits over conventional PCR amplification methods. In comparing dye-based and probe-based techniques, it was revealed that the probe-based method's advantage lay primarily in specificity, which may be associated with the increased propensity of dye-based methods to produce false positives. Furthermore, the heterogeneity of the HF183 primer was not detected in China, Canada, and Singapore respectively, indicating a low likelihood of regional differences. The variation among the 21 other primers may be attributable to regional differences, sample sources, detection techniques, or alternative factors. Finally, we identified that economic factors, climatic conditions, and geographical distribution significantly influence primer performance. [Display omitted] • Meta-analysis for primers and impact factors to their recognition performance. • Viruses-based primers showed a better specificity and recognition ability. • Regional differences of HF183 was not observed in China, Canada, and Singapore. • The influence factors from sample to environment of 21 primers had been listed. • Meta-analysis of economy, climate, and geographic zone on the primers. [ABSTRACT FROM AUTHOR]

• The excellent performance of social media data in urban waterlogging is explained. • A rapid real-time detection approach of urban waterlogging points is proposed. • More than 82% of official waterlogging points were covered in the case study. Urban waterlogging has occurred frequently in recent years due to the impact of climate change and human activities. Real-time waterlogging information is crucial for disaster emergency management, but how to quickly obtain such information remains challenging. Social media data has been widely used to derive damage information because of its high real-time response, low acquisition cost, and high content integration. In this study, we propose an approach to extract real-time waterlogging points from social media data (Sina Weibo). First, social media data is obtained through web crawler technology; Then, de-duplication and de-noising methods are used to filter the data; Finally, a waterlogging point extraction method based on deep learning BERT-BiLSTM-CRF model is proposed to extract waterlogging points. Taking the "7.20" rainstorm in Zhengzhou as an example, there was a rapid increase in the number of social media data during urban waterlogging. Social media data is highly sensitive to urban waterlogging disasters caused by extreme rainstorms. On the day with the heaviest rainfall (July 20), the number of Weibo waterlogging points (331) in the central city was 267 more than the official waterlogging points (64). There were many more Weibo-derived waterlogging points than the real-time official published waterlogging points. The waterlogging points obtained by this approach covered the official published real-time waterlogging points accounted for no less than 82% and they were mostly located around roads, especially in low-lying areas. In general, we demonstrate the feasibility and accuracy of social media data on rapid detection of real-time spatiotemporal variations of waterlogging caused by extreme rainstorms. Urban waterlogging disaster information extracted from social media data can rapidly reflect the real-time spatiotemporal variations of urban waterlogging disasters, and can effectively cover and supplement data reported by government agencies, and can provide data support for urban waterlogging disaster prevention. [ABSTRACT FROM AUTHOR]

Global warming is anticipated to largely impact drought dynamics. Therefore, a comprehensive projection of global drought under various future warming levels is critical for water resources management. This study investigated the changes in the severity, intensity, area, and duration of droughts at 1.5 °C, 2 °C, 3 °C, and 4 °C of global warming above pre-industrial levels based on the latest simulations under climate change scenarios from the Coupled Model Intercomparison Project Phase 6 (CMIP6). The Standardized Precipitation Evapotranspiration Index (SPEI) at 3-month time scale was adopted to characterize seasonal droughts. The results show that: 1) Global land is projected to experience a significant nonlinear increasing trend of drought severity, intensity, areal extent, and duration during the 21st century, and drought characteristics have the highest growth rate under the 3 °C warming scenario, followed by the 4 °C, 2 °C, and 1.5 °C warming scenarios. 2) Under the 1.5 °C and 2 °C warming levels, drought characteristics in most land areas change slightly compared to the baseline period of 1995–2014. 3) Hotspots defined as robust increases in drought severity appear in the 3 °C and 4 °C warming world, including northern South America, Europe, northern and southern Africa, western and central Asia, and central Australia, whereas eastern North America and the Russian Arctic exhibit substantial reduction in drought severity under different global warming levels. 4) Global warming is projected to change the timing of droughts, leading to more frequent summer droughts in Europe. Overall, the findings of this study provide a scientific basis for articulating future global drought adaption and highlight the need for mitigation measures to limit greenhouse gas emissions to achieve the 2 °C target of the Paris Agreement. [Display omitted] • A three-dimensional clustering algorithm is used to analyze drought characteristics. • Global warming is projected to accelerate the growth rate of drought characteristics. • Drought characteristics change slightly in the 1.5 °C and 2 °C warming periods. • More severe drought events will occur at global warming levels of 3 °C and 4 °C. • Europe will suffer more frequent summer droughts as global warming continues. [ABSTRACT FROM AUTHOR]

• WUE trends were determined by the WUE magnitude, followed by atmospheric CO2 concentration and N deposition. • Individualized effects of five driving factors on WUE were quantified through machine learning. • Precipitation was found to shape most of the spatial patterns of WUE. • WUE was increased by increased atmospheric CO 2 concentration, but WUE growth rate declined with increased CO 2 growth rate. • WUE and N deposition exhibited positive or negative correlations depending on the different nutrient constraints on vegetation. The responses of ecosystem water use efficiency (WUE) to environmental perturbations are non-linearly dependent on how strongly coupled are water and carbon cycling. Here, we evaluate the structure of these non-linearities using two high-fidelity explainable machine learning (XML) models to disentangle the confounding effects of the air temperature (Ta), precipitation (PR), downward shortwave radiation (SR), atmospheric CO 2 concentration (Ca), and nitrogen deposition (Ndep) on WUE. The findings suggest that mean annual PR plays a dominant role in shaping the spatial pattern of WUE. Spatially, WUE responded positively to PR and Ca but negatively to Ta and SR , while Ndep had little impact on WUE. For temporal trends, the spatial pattern of the mean annual WUE determined the spatial pattern of the WUE trend. Furthermore, the spatial patterns of the Ndep and Ca trends also contributed substantially to the spatial pattern of the WUE trend. Notably, the WUE and Ca trends exhibited negative correlations, while the WUE and Ndep trends showed positive or negative correlations depending on the different nutrient constraints on vegetation. The WUE growth rate responded negatively to SR in both spatial patterns and temporal trends. Additionally, using the trend of 0.077 K yr−1 and 0 mm yr−1 as the threshold, the trends of Ta and PR shifted from positive to negative relationships on WUE growth. Our results help identify key sensitivities and thresholds in WUE to environmental controls over space and time. [ABSTRACT FROM AUTHOR]

• Actinobacterial diversity and copy number were closely related to methanogenic potential. • Propionibacterium was the biggest contributor to methanogenic potential. • Actinobacteria indirectly affect methanogenic potential by controlling negative cohesion. Microorganisms are the core drivers of coal biogeochemistry and are closely related to biological coalbed methane. However, the Actinobacterial taxa in coals and their roles in the context of biological coalbed methane remain poorly understood. In this study, 16S rRNA gene sequencing and quantitative PCR were used to analyze the Actinobacterial taxa and abundance in coals from different regions of China. The results indicated that Proteobacteria was the predominant bacterial phylum, and Actinobacteria accounted for only 1.64 % of the coal bacterial communities. However, Actinobacteria was the largest contributor to methanogenic potential, followed by Firmicutes and Cyanobacteria. The Shannon diversity, structure and absolute abundance of Actinobacteria were closely related to methanogenic potential. In addition, widely detected genera included Propionibacterium , Corynebacterium , Brevibacterium , Arthrobacter , Micrococcus , Phycicoccus and Brachybacterium , all of which belong to the order Actinomycetales. Among them, Propionibacterium was the most important genus contributing to the methanogenic potential, followed by Corynebacterium and Phycicoccus. In the microbial co-occurrence network, actinobacterial-related nodes and links accounted for 18.29 % and 33.16 % of the total nodes and links, respectively, and actinobacterial OTUs belonging to the genera Propionibacterium , Corynebacterium , Arthrobacter , Dietzia , Phycicoccus , Rhodococcus and Micrococcus were identified as connectors. Furthermore, partial least squares path modeling indicated that Actinobacteria can affect methanogenic potential indirectly by controlling community negative cohesion. In summary, Actinobacteria appear to play important roles in maintaining the microbial co-occurrence network and regulating coal biological methanogenic potential, which is help to understand the coal microbial ecology and geochemical processes. [ABSTRACT FROM AUTHOR]

Nitrogenous disinfection byproducts (N-DBPs) in water are carcinogenic, teratogenic, and mutagenic. In this work, we developed a biomimetic reduction approach based on the cysteine thiol that destructed the highly toxic, select nitrogenous haloacetamides (HAMs) and haloacetonitriles (HANs) while effectively controlling the cytotoxicity of the degradation products to serve as a basis for further technological applications (e.g. immobilized contact bed for terminal users). Mechanisms on toxicity control were elucidated. Results showed the degradation and cytotoxicity control of HAMs as more efficient than that of the HANs. The cytotoxicity of the chlorinated, brominated, and iodinated HAMs and HANs was reduced to 25 %- 0.25 % of the original after biomimetic reduction using a reasonable concentration ratio. Through a combination of thiol-specific reactivity, dehalogenation, and quantitative structure-activity relationship analyses, the major toxicity control mechanisms were found to be the reductive dehalogenation of the N-DBPs. The halogenated functional groups on the N-DBPs had a more pronounced effect than the amide and nitrile groups on the cytotoxicity and detoxification effect. Patterns of toxicity interaction variations with DBPs concentrations were identified to detect possible synergistic cytotoxicity interactions under various combinations of HAMs and HANs in the presence of the cysteine thiol. Results could benefit future N-DBPs control efforts., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Mechanoluminescence (ML) is the nonthermal luminescence generated in the process of force-to-light conversion, which has broad prospects in stress sensing, wearable devices, biomechanics, and multiple information anticounterfeiting. Multivalence emitter ions utilize their own self-reduction process to realize multiband ML without introducing another dopant, such as Eu 3+ /Eu 2+ , Sm 3+ /Sm 2+ , and Mn 4+ /Mn 2+ . However, self-reduction-induced ML in bismuth-activated materials has rarely been reported so far. In this work, a novel visible-to-near-infrared (vis-NIR) ML induced by the self-reduction of Bi 3+ to Bi 2+ in the spinel-type compound (MgGa 2 O 4 ) is reported. The photoluminescence (PL) spectra, PL excitation (PLE) spectra, and PL lifetime curves demonstrate that Bi 3+ /Bi 2+ ions are the main luminescence centers. Notably, the possible self-reduction model is proposed, where a magnesium vacancy (V Mg ″ ) is considered as the driving force for the self-reduction of Bi 3+ to Bi 2+ . Furthermore, an oxygen vacancy (V O •• ) is confirmed by electron paramagnetic resonance (EPR) spectroscopy. Combined with thermoluminescence (TL) glow curves and ML spectra, a plausible trap-controlled ML mechanism is illustrated, where electron-hole (V O •• /V Mg ″ ) pairs play a significant role in capturing electrons and holes. It is worth noting that the proof-of-concept dual-mode electronic signature application is implemented based on the flexible ML film, which improves the capabilities of signature anticounterfeiting for high-level security applications. Besides, multistimulus-responsive luminescence behaviors of the ML film are realized under the excitation of a 254 nm UV lamp, thermal disturbance, 980 nm laser, and mechanical stimuli. In general, this study provides new insights into designing vis-NIR ML materials toward wider application possibilities.

Coal seam microbes, as endogenous drivers of secondary biogenic gas production in coal seams, might be related to methane production in coal seams. In this study, we carried out anaerobic indoor culture experiments of microorganisms from three different depths of bituminous coal seams in Huainan mining area, and revealed the secondary biogas generation mechanism of bituminous coal seams by using the combined analysis of macro-genome and metabolism multi-omics. The results showed that the cumulative mass molar concentrations (Molality) of biomethane production increased with the increase of the coal seam depth in two consecutive cycles. At the genus level, there were significant differences in the bacterial and archaeal community structures corresponding to the three coal seams 1#, 6#, and 9#(p < 0.05). The volatile matter of air-dry basis (V ad ) of coal was significantly correlated with differences in genus-level composition of bacteria and archaea, with correlations of R bacterial = 0.368 and R archaeal = 0.463, respectively. Functional gene analysis showed that the relative abundance of methanogenesis increased by 42% before and after anaerobic fermentation cultivation. Meanwhile, a total of 11 classes of carbon metabolism homologues closely related to methanogenesis were detected in the liquid metabolites of coal bed microbes after 60 days of incubation. Finally, the fatty acid, amino acid and carbohydrate synergistic methanogenic metabolic pathway was reconstructed based on the Kyoto Encyclopedia of Genes and Genomes (KEGG) database. The expression level of mcrA gene within the metabolic pathway of the 1# deep coal sample was significantly higher than that of the other two groups (p < 0.05 for significance), and the efficient expression of mcrA gene at the end of the methanogenic pathway promoted the conversion of bituminous coal organic matter to methane. Therefore, coal matrix compositions may be the key factors causing diversity in microbial community and metabolic function, which might be related to the different methane content in different coal seams., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Studies have shown that Sacubitril/valsartan (Sac/Val) can reduce myocardial inflammation in myocarditis mice, in addition to its the recommended treatment of heart failure. However, the underlying mechanisms of Sac/Val in myocarditis remain unclear. C-type natriuretic peptide (CNP), one of the targeting natriuretic peptides of Sac/Val, was recently reported to exert cardio-protective and anti-inflammatory effects in cardiovascular systems. Here, we focused on circulating levels of CNP in patients with acute myocarditis (AMC) and whether Sac/Val modulates inflammation by targeting CNP in experimental autoimmune myocarditis (EAM) mice as well as LPS-induced RAW 264.7 cells and bone marrow derived macrophages (BMDMs) models. Circulating CNP levels were higher in AMC patients compared to healthy controls, and these levels positively correlated with the elevated inflammatory cytokines IL-6 and monocyte count. In EAM mice, Sac/Val alleviated myocardial inflammation while augmenting circulating CNP levels rather than BNP and ANP, accompanied by reduction in intracardial M1 macrophage infiltration and expression of inflammatory cytokines IL-1β, TNF-α, and IL-6. Furthermore, Sac/Val inhibited CNP degradation and directly blunted M1 macrophage polarization in LPS-induced RAW 264.7 cells and BMDMs. Mechanistically, the effects might be mediated by the NPR-C/cAMP/JNK/c-Jun signaling pathway apart from NPR-B/cGMP/NF-κB pathway. In conclusion, Sac/Val exerts a protective effect in myocarditis by increasing CNP concentration and inhibiting M1 macrophages polarization., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Masson SAS.. All rights reserved.)

The increase in storm surge events caused by climate change exacerbates adverse effects on seawater inundation in coastal areas. An accurate description of the water level curve is crucial for understanding the process of saltwater intrusion (SWI) resulting from storm surge. Most studies involving empirical surges as inputs to groundwater models, often simplify spatial and temporal seawater inundation processes, which may increase the uncertainty in vertical seawater intrusion. To address this gap, we employed a comprehensive modeling approach using storm surge model ADCIRC and numerical simulator HydroGeoSphere to reveal SWI dynamics during a historical storm surge event in a coastal farm, considering varying tidal-surge phases and typhoon intensities. Our findings indicate pronounced SWI variations even with consistently highest water level during a storm surge, contingent on prior tidal processes. The timing of typhoon landfall on an hourly scale yielded diverse water level curves, altering the function of SWI. Intriguingly, SWI exacerbates following a high tide with 31.2 % average salinity higher, highlighting the profound modulation effect of tidal levels on SWI. Local topography significantly influenced SWI dynamics. Ponds, for instance, retained elevated salinity levels for over 15 h, indicating a more prolonged exposure to salinity than roads. These findings underscore the importance of considering both tidal influences and topographical factors in understanding and mitigating SWI in coastal agricultural management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The influence of enrichment of culturable microorganisms in in situ coal seams on biomethane production potential of other coal seams has been rarely studied. In this study, we enriched culturable microorganisms from three in situ coal seams with three coal ranks and conducted indoor anaerobic biomethane production experiments. Microbial community composition, gene functions, and metabolites in different culture units by 16S rRNA high-throughput sequencing combined with liquid chromatography-mass spectrometry-time-of-flight (LC-MS-TOF). The results showed that biomethane production in the bituminous coal group (BC)cc resulted in the highest methane yield of 243.3 μmol/g, which was 12.3 times higher than that in the control group (CK). Meanwhile, Methanosarcina was the dominant archaeal genus in the three experimental groups (37.42 ± 11.16-52.62 ± 2.10%), while its share in the CK was only 2.91 ± 0.48%. Based on the functional annotation, the relative abundance of functional genes in the three experimental groups was mainly related to the metabolism of nitrogen-containing heterocyclic compounds such as purines and pyrimidines. Metabolite analysis showed that enriched microorganisms promoted the degradation of a total of 778 organic substances in bituminous coal, including 55 significantly different metabolites (e.g., purines and pyrimidines). Based on genomic and metabolomic analyses, this paper reconstructed the heterocyclic compounds degradation coupled methane metabolism pathway and thereby preliminarily elucidated that enriched culturable bacteria from different coal-rank seams could promote the degradation of bituminous coal and intensify biogenic methane yields., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Human fecal contamination in urban rivers poses significant health risks, but their potential connections with other substances like dissolved organic matter (DOM) remain underexplored. In this study, five fecal pollution markers related to fecal Bacteroides or human fecal contamination (AllBac, HF183, BacH, Hum2, and Hum163) and DOM along an urban river were analyzed using quantitative polymerase chain reaction (qPCR) and three-dimensional excitation-emission (3D EEM) fluorescence spectrometry. All five markers were detected with average absolute abundance ranging from 2.51 to 6.28 lg gene copies/100 mL, showing a progressive increase along the river (R 2  = 0.29-0.92, p < 0.05). Parallel factor analysis identified three dominant DOM components (humic acid-like, fulvic acid-like, and protein-like), with strong positive correlations between protein-like components and all fecal markers (R 2  = 0.59-0.66, p < 0.001). Both fecal and DOM distributions consistently showed significant differences between upstream and downstream areas (p < 0.001), suggesting their complementary assessment. While DOM was more sensitive to environmental variables such as rainfall, rubber dam, and tidal dynamic, the combination of fecal pollution markers and 3D EEM analysis allowed a more comprehensive assessment of contamination levels, mitigating potential biases caused by the influence of multiple factors on a single method. Furthermore, due to the strong correlation between protein-like and fecal markers in the DOM, 3D EEM can be used as a pre-detection means for qPCR detection, reducing testing time and costs., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Compound Drought and Saltwater intrusion Events (CDSEs) refer to hydrologic drought and saltwater intrusion occurring simultaneously or consecutively in estuaries, and exacerbate the negative impacts resulting from an individual extreme event. CDSEs have been drawing increasing attention due to their potential adverse impacts on water resources, crop production, and food security. A new Standardized compound Drought and Saltwater intrusion Index (SDSI) was developed in this study to systematically detect changes in the severity of CDSEs in six estuaries (Little Back, Ebro, Rhine, Orange, Pearl River and Murray). The results illustrated that (1) compared to the Standardized Runoff Index (SRI), SDSI effectively characterizes and quantifies the occurrences and severity of CDSEs in major river estuaries worldwide. (2) Temporally, the SDSI trend varied across estuaries. Specifically, a decreasing trend was observed in the Little Back, Ebro, and Orange estuaries, with corresponding Zs values of -2.43, -3.63, and -3.23. (3) Spatially, moderate CDSEs occurred more frequently among different estuaries, and their frequency, duration and severity varied in different estuaries. Notably, Ebro, Rhine and Murray River estuaries had the highest probability of CDSEs, nearing 60%. Among them, the Murray Estuary had the longest average duration, spanning 7.68 months, and the highest severity was 5.94. (4) According to the contributions analysis, saltwater intrusion plays a dominant role in influencing SDSI severity, accounting for a substantial percentage (54%-95.30%) compared to runoff. Notably, the Orange Estuary experienced the greatest impact from saltwater intrusion (81.54%-95.30%), while the Murray Estuary had relatively equal contributions from hydrological drought and saltwater intrusion., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Coagulation with or without pre-oxidation are important drinking water treatment processes. However, the efficacy of these processes in mitigating water toxicity remains unknown. To further improve drinking water safety, we employed water from the Pearl River Delta region of southern China to investigate a treatment approach consisting of coagulation with or without pre-oxidation to simultaneously modulate health-relevant cytotoxicity to CHO cells, on top of the conventional foci of turbidity and dissolved organic carbon (DOC) during water treatment. Three coagulants (two aluminum-based and one iron-based salts) and three pre-oxidants (ozone, permanganate, and peroxymonosulfate) were studied. For coagulation without pre-oxidation, intermediate coagulant doses and pH reached optimum cytotoxicity to CHO cells, turbidity, and DOC control simultaneously. Introducing oxidants reduced cytotoxicity to CHO cells significantly, enhanced by increasing oxidant concentrations and pre-oxidation duration. The cytotoxicity to CHO cells mitigation capabilities of three pre-oxidants were: ozone > peroxymonosulfate > potassium permanganate. Modulation of water cytotoxicity to CHO cells was mostly attributable to controlling DOC (specifically humic-acid like substances, tyrosine, tryptophan). However, the addition of pre-oxidants led to significant shifts in water cytotoxicity to CHO cells forcing drivers, rendering humic-acid like substances the sole decisive cytotoxicity-inducing fluorophores. For the first time, 'sweet spots' were identified to simultaneously monitor cytotoxicity to CHO cells alongside turbidity and DOC. These methods better modulate water cytotoxicity to CHO cells without sacrificing conventional water treatment goals while shedding light onto the mechanisms behind., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Disinfection is essential to swimming pool water (SPW) quality. Peracetic acid (PAA) has attracted attention for water disinfection for advantages such as less formation of regulated DBPs. Persistence kinetics of disinfectants is difficult to elucidate in pools because of the complex water matrix stemming from body fluid loadings from swimmers and long residence times. In this research, the persistence kinetics of PAA was investigated in SPW benchmarked against free chlorine, use bench-scale experiments and model simulation. Kinetics models were developed to simulate the persistence of PAA and chlorine. The stability of PAA was less sensitive to swimmer loadings than chlorine. An average swimmer loading event reduced the apparent decay rate constant of PAA by 66 %, a phenomenon that diminished with increasing temperatures. L-histidine and citric acid from swimmers were identified as main retardation contributors. By contrast, a swimmer loading event instantaneously consumed 70-75 % of the residual free chlorine. The required total dose of PAA was 97 % less than chlorine under the 3-days cumulative disinfection mode. Temperature was positively correlated with disinfectant decay rate, with PAA being more sensitive than chlorine. These results shed light on the persistence kinetics of PAA and its influential factors in swimming pool settings., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Precipitation whiplash, including abrupt shifts between wet and dry extremes, can cause large adverse impacts on human and natural systems. Here we quantify observed and projected changes in characteristics of sub-seasonal precipitation whiplash and investigate the role of individual anthropogenic influences on these changes. Results show that the occurrence frequency of global precipitation whiplash is projected to be 2.56 ± 0.16 times higher than in 1979-2019 by the end of the 21 st Century, with increasingly rapid and intense transitions between two extremes. The most dramatic increases of whiplash show in the polar and monsoon regions. Changes in precipitation whiplash show a much higher percentage change than precipitation totals. In historical simulations, anthropogenic greenhouse gas (GHG) and aerosol emissions have increased and decreased precipitation whiplash occurrences, respectively. By 2079, anthropogenic GHGs are projected to increase 55 ± 4% of the occurrences risk of precipitation whiplash, which is driven by shifts in circulation patterns conducive to precipitation extremes., (© 2023. The Author(s).)

The Budyko-based elasticity method has been widely employed to clarify the driving factors behind runoff changes. However, different formulations of the Budyko framework could produce biases in the elasticity analysis and the assessment errors induced from different formulations of the Budyko framework in the elasticity method remain unclear. Here, we attempt to address this issue by validating the performance of elasticity methods derived from two analytical Budyko equations (Fu's equation and Choudhury's equation), as well as one empirical Budyko equation (Wang-Tang's equation) of the Budyko framework across 22 basins in China. Validations show that the runoff change simulated by the elasticity method derived from the empirical equation has lower errors compared with the two analytical Budyko equations. Results reveal that in the semi-humid environment, the alteration of basin characteristics takes the main responsibility for the runoff change. However, a clear divergence was found in simulated runoff changes among different Budyko-based elasticity methods in humid basins. For parts of the humid basin, the precipitation is the main driver of runoff change from the analytical Budyko-based elasticity methods, while the alteration of basin characteristics is the main derive of the runoff changes according to based on the empirical Budyko-based elasticity method. This difference could be attributed to the variations in the simulated contributions from the alteration of basin characteristics on runoff changes. Generally, our results highlight the importance of validating different Budyko equations when applying the elasticity method to investigate the driver of the runoff changes in humid regions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)