bluuebunny/crossref_metadata_2025 huggingface dataset:
Phloem Sap and Wood Carbon Isotope Abundance (δ13C) Varies with Growth and Wood Density of Eucalyptus globulus under Nutrient Deficit and Inform Supplemental Nutrient Application
Authors: Halder Nirmol Kumar , Chowdhury Md. Qumruzzaman , Fuentes David , Possell Malcolm , Bradshaw Benjamin , Mukul Sharif A. , Merchant Andrew
Published: April 2024

Eucalyptus globulus, commonly known as blue gum or southern blue gum, is a tall, evergreen tree endemic to southeastern Australia. E. globulus is grown extensively in plantations to improve the sustainability of timber and fibre production across Australia. Sustainable forest management practices necessitate the consideration of ‘off-site’ carbon and ecological footprints. Pursuing optimal supplemental nutrient application and maximum growth rates is therefore critical to the establishment of a sustainable timber and fibre production industry. Biological indicators that can predict growth responses are therefore of extreme value. We investigated the carbon isotope abundance of wood cellulose (δ13Ccel) in E. globulus to determine potential relationships with the carbon isotope abundance of phloem sap (δ13Cphl) where the trees were subjected to different level of nutrient availability. This study also sought to determine the effect of nutrient additions on the growth of the E. globulus and to quantify the relationship between the volumetric growth of wood and δ13Ccel. Phloem sap and wood cores were collected from trees within study plots which were subjected to seven nutrient treatments over a two-year period in a monoculture E. globulus plantation in South Australia. Phloem sap was collected using the razor blade technique and wood cores were collected using a stem borer. The carbon isotope abundance (δ13C) of phloem sap and wood grown in the radial direction of the stem were determined. The basic and dry densities of wood were determined, and their relationships with phloem and wood δ13C were established. The δ13Cphl was significantly correlated with δ13Ccel. The relationship between δ13Ccel and the wood density of the respective wood sections was significant but did not consistently show the same pattern. There was no significant variation in basic density observed along the radial direction of the stem wood of the short-rotation E. globulus trees. A positive correlation was observed between δ13Ccel and the wood basic density, but the relationship was not consistent along the radial direction of the stem. However, positive correlations were observed between δ13Ccel and the air-dry density of respective wood sections. The relationship between phloem and wood δ13C and the relationship between δ13C and wood density along the radial direction of the stem needs to be considered while monitoring forest growth under nutrient- and water-limited conditions.
Study on Transportation Green Efficiency and Spatial Correlation in the Yangtze River Economic Belt
Authors: Li Yangzhou , Li Cheng , Feng Dongni
Published: April 2024

The Yangtze River Economic Belt (YREB), a crucial transportation corridor spanning China’s east and west and linking coastal and inland regions, is not only pivotal in the nation’s strategic development but also drives regional economic and social progress through its transportation industry. Despite rapid growth, the industry faces challenges such as low efficiency, resource supply–demand imbalances, and environmental issues. To advance green and sustainable progress, this study establishes a regional transportation green efficiency evaluation system. Using principal component analysis (PCA) to refine input data, the undesirable super-SBM model quantitatively assesses green transportation efficiency (GTE) in YREB provinces and cities, revealing regional disparities. The study also explores spatial correlations and distribution characteristics of GTE. Results indicate that ① YREB’s GTE shows a U-shaped trend, with significant differences between upper, middle, and lower reaches, being stronger in the east and weaker in the west (lower > middle > upper reaches); ② GTE exhibits spatial correlation in YREB regions, with clear clustering; and ③ cold and hot spots of GTE in the middle reaches are relatively stable, with upstream areas generally cold or sub-cold, and hot spots mainly downstream.
Advancing the Decarbonization of the Construction Sector: Lifecycle Quality and Performance Assurance of Nearly Zero-Energy Buildings
Authors: Piaia Emanuele , Turillazzi Beatrice , Di Giulio Roberto , Sebastian Rizal
Published: April 2024

Dealing with and maintaining high-quality standards in the design and construction phases is challenging, especially for on-site construction. Issues like improper implementation of building components and poor communication can widen the gap between design specifications and actual conditions. To prevent this, particularly for energy-efficient buildings, it is vital to develop resilient, sustainable strategies. These should optimize resource use, minimize environmental impact, and enhance livability, contributing to carbon neutrality by 2050 and climate change mitigation. Traditional post-occupancy evaluations, which identify defects after construction, are impractical for addressing energy performance gaps. A new, real-time inspection approach is necessary throughout the construction process. This paper suggests an innovative guideline for prefabricated buildings, emphasizing digital ‘self-instruction’ and ‘self-inspection’. These procedures ensure activities impacting quality adhere to specific instructions, drawings, and 3D models, incorporating the relevant acceptance criteria to verify completion. This methodology, promoting alignment with planned energy-efficient features, is supported by BIM-based software and Augmented Reality (AR) tools, embodying Industry 4.0 principles. BIM (Building Information Modeling) and AR bridge the gap between virtual design and actual construction, improving stakeholder communication and enabling real-time monitoring and adjustments. This integration fosters accuracy and efficiency, which are key for energy-efficient and nearly zero-energy buildings, marking a shift towards a more precise, collaborative, and environmentally sensible construction industry.
Investigating the Impact of Green Space Ratio and Layout on Bioaerosol Concentrations in Urban High-Density Areas: A Simulation Study in Beijing, China
Authors: Jian Wenchen , He Hao , Wang Boya , Liu Zhicheng
Published: April 2024

The COVID-19 pandemic significantly impacted global development. Through bioaerosols emitted by human respiration, respiratory infectious diseases, including COVID-19, are transmitted. The bioaerosol concentrations can be affected by the urban climate and morphology. However, the effects of urban green spaces on bioaerosol concentrations remain unclear. Focusing on the dormitory area of Beijing Forestry University, this study first investigated the influence of different green space ratios on the average bioaerosol concentrations using the ENVI-met software. Moreover, both overall and local green space layouts were analyzed for their impact on bioaerosol concentrations. The results indicated that ventilation conditions were the primary factor influencing bioaerosol concentrations. During peak congestion, a 10% increase in the green space ratio resulted in a 2% rise in the average bioaerosol concentration. Furthermore, a distributed layout resulted in a 1.3% higher average bioaerosol concentration than a concentrated layout with an equivalent green space ratio. Enacting strategies such as Roadside Green Spaces Retreat, Road Spaces Expansion, and Intersection Green Spaces Chamfering led to reductions in local bioaerosol concentrations by up to 17.7%, 18.44%, and 12.69%, respectively. This study highlights the importance of adjusting green space layouts in urban high-density areas after the pandemic, reducing the risk of population exposure to bioaerosol concentrations.
Unveiling the Significance: Sustainability and Environmental Disclosure in Saudi Arabia through Stakeholders’ Theory
Authors: Aladwey Laila Mohamed Alshawadfy , Alsudays Raghad Abdulkarim
Published: April 2024

Our study investigates sustainability and environmental disclosure in Saudi Arabian accounting, focusing on stakeholder accountability. Employing content analysis and close reading, we examine disclosures in the annual reports of 18 companies from 2008 to 2018. Findings reveal limited disclosures, influenced by interpretations of Islam and government emphasis. Despite sector-specific attention to environmental issues, disclosures lack depth. The study offers insights into managerial motivations, highlighting divergent stakeholder priorities and moral obligations. Policy implications suggest mandatory regulations could enhance accountability and encourage comprehensive disclosures. The research underscores the significance of contextual understanding in shaping accounting practices, particularly in regions like Saudi Arabia. Regulatory changes could improve corporate reporting on environmental and sustainability matters, addressing societal needs more effectively.
Goodbye Plastic Bags? Lessons from the Shopping Plastic Bag Ban in Chile
Authors: Frey Maximiliano , Cifuentes Luis A.
Published: April 2024

Bans on single-use plastic shopping bags (SUPBs) are a popular policy to tackle plastic pollution. However, their success has been evaluated solely based on reduced SUPBs consumption, ignoring the impacts of substitutes. This article addresses this gap by analyzing the Chilean plastic bag ban law. Results show a reduction of ~249 kilotons of SUPBs consumed and a change in the materiality of shopping bags (mainly toward paper), but also an increase of more than 50% of bin liners after the enactment of the ban. Despite some undesired effects, an improvement in the environmental performance of the bag market is obtained in fifteen of the eighteen categories studied. The environmental impacts are on average 38% lower than in the counterfactual scenario. This suggests that the law is being effective in protecting the environment. The strictness of the ban and its rapid enforcement were positive aspects of its design, but ignoring the end-of-life of the bags could be limiting its impact. To reduce the environmental impact of substitutes, it is recommended to create design guidelines for shopping bags and bin liners.
Research on a New Soundscape Evaluation Method Suitable for Scenic Areas
Authors: Liu Jing , Dan Ziyan , Yan Zengfeng
Published: April 2024

Existing studies have focused mainly on the environmental quality of scenic spots, such as sufficient oxygen content in the air and a high concentration of negative oxygen ions. The perceptions of soundscape in scenic areas are generally good, but there are few reports on the quantitative evaluation of soundscape quality in scenic areas. In this study, we analysed existing methods for evaluating the soundscape of a landscape, evaluated the soundscape comfort of scenic spots, analysed and refined the natural environmental factors affecting the soundscape, and proposed for the first time to use physical environmental indicators such as the air temperature difference, relative humidity, natural illuminance ratio and wind speed as environmental evaluation variables. A quantitative method was used to calculate the soundscape comfort index (SSI) of the landscape. The physical environmental indicators related to famous scenic spots in China, namely, Qingcheng mountain field testing and a subjective soundscape of tourist satisfaction survey, were used to calculate the corresponding soundscape comfort index values, and a quantitative analysis of soundscape comfort and differences in temperature, relative humidity, the illumination ratio, and the correlation between the equivalent sound level A was performed. The measured values of the temperature difference and light ratio were significantly correlated with the soundscape comfort index. The distribution of sound landscape comfort was given by a GIS map, and soundscape comfort was evaluated scientifically. The correlations between soundscape comfort and landscape patch number (PN), landscape patch density (PD), diversity index (Shannon), and landscape shape index (LSI) were quantitatively analysed, which confirmed that the perception of soundscape comfort was affected by landscape space to different degrees. This study has scientific significance and application value for the soundscape evaluation of scenic areas and has significance for soundscape evaluation and design strategies for urban landscapes.
Bibliometric Analysis of Research Progress and Trends on Carbon Emission Responsibility Accounting
Authors: Du Yingying , Liu Haibin , Huang Hui
Published: April 2024

The severity of global climate change is a pressing issue, and carbon emission reduction requires collaboration between producers and consumers. Carbon emission responsibility accounting is critical for distributing the tasks associated with carbon reduction. To examine the current research status and future development trends of carbon emission responsibility accounting, we used the scientific quantitative knowledge graph method and CiteSpace software. We analyzed the data from 4089 studies retrieved from the Web of Science and China National Knowledge Infrastructure databases, focusing on various aspects such as the number of published papers, subjects, research focuses, research content, and future research directions. In 2022, the number of publications was 657. The largest number of published carbon emission responsibility accounting documents was published by scholars from China: there were 708 published articles, 35% of the 2002 articles published in the Web of Science. The reason may be that China, as a developing country, produces more carbon emissions. In order to actively shoulder international responsibilities and slow down global warming, China strengthened its research on carbon emission responsibility, the basic work on carbon emission reduction. This was followed by the United States and England. England showed high levels of research collaboration. “Environmental science” was one of the main subjects in the Web of Science database, representing 43.96% of total publications. Research focuses included input–output analyses and implied carbon export trade. This study summarizes the literature on carbon emission responsibility accounting in terms of research perspectives, accounting principles, and accounting methods. In the future, the accounting of carbon emission responsibility at the city level considering the carbon emission responsibility sharing method including three or more shared parties and accounting for the carbon emission responsibility between the upstream and downstream from the perspective of the industrial chain can be studied. The findings of this study provide guidance to researchers and policymakers for the progression and enhancement of carbon emission responsibility accounting.
Electricity Consumption, Renewable Energy Production, and Current Account of Organisation for Economic Co-Operation and Development Countries: Implications for Sustainability
Authors: Naidu Suwastika , Chand Anand , Pandaram Atishwar , Vosikata Sunia
Published: April 2024

This paper uses the bootstrapped Granger Causality Testing approach to investigate the relationship between electricity consumption, renewable energy production, and the current account of the six OECD countries. One of the main advantages of using this approach is that it captures the cross-section dependence in our sample and applies the Seemingly Unrelated Regression (SUR) to examine the causality relationship between the variables. The empirical findings show the presence of cross-section dependence in our sample as the six Organisation for Economic Co-operation and Development (OECD) countries share resources, capabilities, and key competencies. Notably, a unidirectional causality exists running from electric power consumption to the current account of the USA. The current account balance causes electric power consumption in the case of France and Switzerland. The tri-variate causality relationship between electricity consumption, renewable energy production, and current account balance could not be established in the case of Germany, Finland, or the UK.
Groundwater and Tourism: Analysis of Research Topics and Trends
Authors: Lamhour Oumaima , El Bouazzaoui Imane , Perkumiené Dalia , Safaa Larbi , Aleinikovas Marius , Škėma Mindaugas
Published: April 2024

Recent years have seen an increase in the popularity of exploring the correlation between groundwater and tourism as a research topic. Although previous studies have touched on certain aspects of this relationship, none has yet plunged to the heart of the matter. This Bibliometric study examines the literature on the relationship between tourism and groundwater in the overall context of economic development. The bibliometric tools VOS Viewer version 1.6.19 and R Bibliometrix were employed to analyze 104 publications selected via the Preferred Reporting Items for Systematic Reviews and Meta-Analyses diagram. The results suggest a growing interest in the subject and the need for broader and collaborative research, to fully understand these dynamics. Major contributions come from Spanish, American, Chinese, and Mexican authors, focusing on sustainability, anthropogenic impact, physical characteristics, and groundwater quality. In conclusion, this study provides an overview of the current research landscape, identifies trends and gaps, and encourages international collaboration for a better understanding of groundwater issues in the tourism context. Although our work provides very important knowledge, it should be recognized that the analysis is made only based on the Scopus-indexed literature. This restriction highlights the necessity for future research to do a more comprehensive and integrated bibliometric analysis. The array of research sources will thus definitely enhance the joint academic knowledge on that subject and lead to more inclusive and, therefore, higher-quality academic discourse.
Specificity of DNA ADP-Ribosylation Reversal by NADARs
Authors: Cihlova Bara , Lu Yang , Mikoč Andreja , Schuller Marion , Ahel Ivan
Published: April 2024

Recent discoveries establish DNA and RNA as bona fide substrates for ADP-ribosylation. NADAR (“NAD- and ADP-ribose”-associated) enzymes reverse guanine ADP-ribosylation and serve as antitoxins in the DarT-NADAR operon. Although NADARs are widespread across prokaryotes, eukaryotes, and viruses, their specificity and broader physiological roles remain poorly understood. Using phylogenetic and biochemical analyses, we further explore de-ADP-ribosylation activity and antitoxin functions of NADAR domains. We demonstrate that different subfamilies of NADAR proteins from representative E. coli strains and an E. coli-infecting phage retain biochemical activity while displaying specificity in providing protection from toxic guanine ADP-ribosylation in cells. Furthermore, we identify a myxobacterial enzyme within the YbiA subfamily that functions as an antitoxin for its associated DarT-unrelated ART toxin, which we termed YarT, thus presenting a hitherto uncharacterised ART-YbiA toxin–antitoxin pair. Our studies contribute to the burgeoning field of DNA ADP-ribosylation, supporting its physiological relevance within and beyond bacterial toxin–antitoxin systems. Notably, the specificity and confinement of NADARs to non-mammals infer their potential as highly specific targets for antimicrobial drugs with minimal off-target effects.
Higher Time-Derivative Theories from Space–Time Interchanged Integrable Field Theories
Authors: Fring Andreas , Taira Takano , Turner Bethan
Published: April 2024

We compare a relativistic and a nonrelativistic version of Ostrogradsky’s method for higher-time derivative theories extended to scalar field theories and consider as an alternative a multi-field variant. We apply the schemes to space–time rotated modified Korteweg–de Vries systems and, exploiting their integrability, to Hamiltonian systems built from space–time rotated inverse Legendre transformed higher-order charges of these systems. We derive the equal-time Poisson bracket structures of these theories, establish the integrability of the latter theories by means of the Painlevé test and construct exact analytical period benign solutions in terms of Jacobi elliptic functions to the classical equations of motion. The classical energies of these partially complex solutions are real when they respect a certain modified CPT-symmetry and complex when this symmetry is broken. The higher-order Cauchy and initial-boundary value problem are addressed analytically and numerically. Finally, we provide the explicit quantization of the simplest mKdV system, exhibiting the usual conundrum of having the choice between having to deal with either a theory that includes non-normalizable states or spectra that are unbounded from below. In our non-Hermitian system, the choice is dictated by the correct sign in the decay width.
Comparison of Xylazine and Lidocaine Infusion versus Medetomidine Continuous Rate Infusion during General Anesthesia with Isoflurane in Horses Undergoing Emergency Laparotomy
Authors: Straticò Paola , Guerri Giulia , Bandera Lorenza , Celani Gianluca , Di Nunzio Laura , Petrizzi Lucio , Varasano Vincenzo
Published: April 2024

(1) The main goals of general anesthesia include pain management and a safe anesthetic protocol for smooth recovery. In this retrospective study, we compared two anesthetic protocols for general anesthesia with isoflurane during emergency laparotomy: sedation with xylazine and the intraoperative infusion of lidocaine (X group) versus medetomidine as a preoperative sedation and intraoperative infusion (M group). (2) The medical records of horses who underwent emergency laparotomies between 2016 and 2023 were reviewed. According to the anesthetic protocol, patients were allocated to the X or M groups. Data about the horse, signalment, history, and anesthetic variables were analyzed. (3) Group X had a significantly higher heart rate (HR), lower respiratory rate (RR) and mean and diastolic arterial pressure (MAP/DAP). A progressive increase in HR and RR was observed in both groups. Group X underwent a decrease in RR and an increase in DAP. In Group M, a decrease in MAP and DAP was observed. Group M exhibited a longer recovery time with similar recovery scores. Both protocols provided safe anesthesia for emergency laparotomy, with minor cardiovascular and respiratory depression. Minor respiratory depression was detected when xylazine was used, while recovery was longer with medetomidine.
The Treatment of Antibiotic Excess Sludge via Catalytic Wet Oxidation with Cu-Ce/γ-Al2O3 and the Production of a Carbon Source
Authors: Chu Shangye , Lin Hai , Zeng Xu
Published: April 2024

In the present study, the effectiveness of catalytic wet oxidation triggered by using Cu-Ce/γ-Al2O3 to degrade antibiotic excess sludge was investigated, during which some small molecule carboxylic acids were produced, which are valuable in biological wastewater treatment as an organic carbon source. The influence of reaction parameters on the degradation efficiency was explored through single-factor and orthogonal experiments, including catalyst amount, reaction temperature and time, and oxygen supply amount. The results illustrated that the treatment system can achieve 81.2% COD and 93.8% VSS removal rates under optimized reaction conditions. Carboxylic acids produced after the sludge degradation mainly included acetic acid, propanoic acid, etc. The results of wastewater biological treatment experiments exhibited that the degraded solution after catalytic wet oxidation has potential to be used as a carbon source to meet the demand of biological treatment, which helps the removal of COD and TN. This work confirms the effectiveness of catalyst for enhancing antibiotic excess sludge treatment, which provided a new idea for the rational disposal of antibiotic excess sludge.
Investigating the Impact of Large Lakes on Local Precipitation: Case Study of Lake Urmia, Iran
Authors: Mousavi Hossein , Dehghanipour Amir Hossein , Ferreira Carla S.S. , Kalantari Zahra
Published: April 2024

Large lakes face considerable challenges due to human activities and climate change, impacting local weather conditions and ecosystem sustainability. Lake Urmia, Iran’s largest lake and the world’s second-largest saltwater lake, has undergone a substantial reduction in water levels, primarily due to drought, climate change, and excessive irrigation. This study focuses on the potential repercussions on local climate conditions, particularly investigating the impact of moisture sources, evaporation from lake surfaces, and evapotranspiration from agricultural activities, on local convection rainfall. The prevailing westerly winds in the basin suggest a hypothesis that this moisture is transported eastward within the basin, potentially leading to local precipitation as it ascends to higher altitudes near the eastern basin border. To validate this hypothesis, climate data from 1986 to 2017 from the Sarab meteorological station (east of the lake basin, influenced by local precipitation) and Saqez meteorological station (south of the basin, unaffected by local precipitation) were analyzed. The impact of lake water level reduction was assessed by categorizing data into periods of normal lake conditions (1986–1995) and water level reduction (1996–2017). Additionally, the MSWEP global precipitation product was used to examine the precipitation distribution in the entire basin over the entire period and sub-periods. The findings indicate Lake Urmia’s significant influence on convective rainfall in the eastern basin, especially during the summer. Despite decreasing lake levels from 1996 to 2017, convective rainfall in the eastern basin increased during the summer, suggesting intensified agricultural irrigation, particularly in hot seasons.
Elevational Patterns of Forest Evapotranspiration and Its Sensitivity to Climatic Variation in Dryland Mountains
Authors: Li Hongyu , Liu Xiaohuang , Zhang Wenbo , Zhu Haoyang , Zhao Xiaofeng , Liu Jiufen , Luo Xinping , Wang Ran , Zhao Honghui , Wang Chao
Published: April 2024

Elevational climatic heterogeneity, complex terrains, and varying subsurface properties affect the sensitivity of evapotranspiration (ET) in dryland mountain forests to hydrometeorological changes. However, the elevational distribution of ET sensitivity and its major influencing factors remain poorly understood. This study focused on the mid-altitude zone (1000–3500 m) forests in the Chinese Western Tianshan Mountains and assessed ET sensitivity to multiple climate variables, including precipitation (P) and potential evapotranspiration (PET), from 2000 to 2020. To evaluate the multi-year mean and trends in ET sensitivity, multi-source remote sensing data and regional survey data were analyzed using Spearman’s correlation coefficient, the sliding window method, and Kendall’s test. Furthermore, the relative importance of environmental variables (topography, geology, soil, and vegetation) was investigated. P and PET showed no significant trends, while ET exhibited a significant increasing trend (5.81 mm/yr, p < 0.01), particularly at elevations above 2000 m. Most forests (93.5%) showed a positive sensitivity of ET to P, and 70.0% showed a positive sensitivity of ET to PET, mainly at elevations of 1500–2500 m. Additionally, the trend in ET sensitivity to P decreased with an increasing elevation, with 64.5% showing a positive trend. Meanwhile, the trend in ET sensitivity to PET increased with elevation, with 88.1% showing a positive trend. Notably, 53.2% of the forests showed increasing ET sensitivity trends to both P and PET, primarily at elevations of 2000–3000 m with a mean normalized difference vegetation index (NDVI) of 0.56. Geological factors, particularly the hydrological properties of weathered bedrock, contributed the most (~47%) to mean sensitivity. However, geological and vegetative factors, including the NDVI and root zone water availability, were the main contributors (35% each) to the sensitivity. This study highlights the elevation-dependent sensitivity of dryland mountain forests to hydrothermal changes, with higher-elevation forests (>2000 m) being more sensitive to global warming.
Multi-Objective Design of a Horizontal Flow Subsurface Wetland
Authors: Mendez-Valencia Jhonatan , Sánchez-López Carlos , Reyes-Pérez Eneida
Published: April 2024

An artificial wetland is used to treat gray, waste, storm or industrial water. This is an engineering system that uses natural functions of vegetation, soil and organisms to provide secondary treatment to gray water. In the physical design of each artificial wetland, there are various action factors that must meet certain characteristics so that the level of gray-water pollution is reduced. In this sense, several design methodologies have been developed and reported in the literature, but some are customized designs and often do not meet the required decontamination objectives. This challenge increases as the complexity of the task in its structure also increases. Particularly in this work, a multi-objective evolutionary algorithm is used to optimize the physical design of a horizontal flow subsurface wetland (HFSW) for gray-water treatment. The study aims to achieve two objectives: first, to minimize the physical volume, and second, to maximize the contaminant removal efficiency. The defined objective functions depend on six design variables called hydraulic retention time, width, length, water depth inside the wetland, substrate depth and slope. Three constraint functions are also defined: removal efficiency greater than 95%, physical volume below 500 m3 and compliance with a length–width ratio is 3:1, varying the population size and number of generations equal to 200, 400, and 600. The set of solutions according to the number of generations as well as the Pareto front corresponds to the best solution that complies with the constraints of the problem of oversizing the HFSW, and the Pareto front shows the interaction between the objectives and their behavior, reflecting the problem’s nature as minimization–maximization.
Flexural-Gravity Waves in a Channel with a Compressed Ice Cover
Authors: Batyaev Evgeniy , Khabakhpasheva Tatiana
Published: April 2024

The characteristics of linear hydroelastic waves propagating in a channel covered with compressed ice are investigated. The channel has a rectangular cross-section and is assumed to be infinite in length. The fluid in the channel is non-viscous and incompressible; its flow is potential. The ice cover is modelled by an elastic plate of constant thickness frozen to the channel walls. Principal attention is paid to the investigation of the influence of ice compression on the parameters of hydroelastic waves. The problem is solved in a coupled hydroelastic formulation. The profiles of propagating waves in the channel are sought in the form of series on the normal modes of a dry plate. The modes are defined analytically through trigonometric and hyperbolic functions. It is shown that compression in the longitudinal and transverse directions has different effects on the dispersion relations of these hydroelastic waves, their shape and phase, as well as on the critical velocities and strains distribution.
Effects of Three Antibiotics on Nitrogen-Cycling Bacteria in Sediment of Aquaculture Water
Authors: Li Zhu , He Huan , Ding Jianhe , Zhang Zhizhong , Leng Yifei , Liao Mingjun , Xiong Wen
Published: April 2024

Antibiotics are commonly used to prevent and control aquaculture diseases. However, long-term overuse of antibiotics not only leaves residues but also leads to changes in the nitrogen cycle in water, which threatens the survival of aquaculture organisms. The current results showed that sulfamethoxazole had no significant effect on the nitrogen cycle process in the actual aquaculture concentration. The inhibitory effect of 1.05 mg/L norfloxacin on ammonia-oxidizing bacteria was significantly greater than that on ammonia-oxidizing archaea, and the gene abundance of AOB amoA on the 14th day increased by 2.48 times compared with the 7th day. Under the influence of 3.9 mg/L oxytetracycline, the gene abundance of AOB amoA decreased significantly, while the number of AOA amoA genes increased, suggesting that there may be functional redundancy between AOA and AOB. At the genus level in the norfloxacin group, the relative abundance of Sva0485 increased by 14.0% on the 7th day compared with the control group but decreased 12.77% in the addition group. The relative abundance of Firmicutes, another dominant species in the oxytetracycline group, was 25.9%. This study shows that the addition of antibiotics may have a negative effect on the nitrogen-cycling microorganisms in aquaculture water.
Vine Copula-Based Multivariate Distribution of Rainfall Intensity, Wind Speed, and Wind Direction for Optimizing Qatari Meteorological Stations
Authors: Qasem Hassan , Joergensen Niels-Erik , Rahman Ataur , Samman Husam Abdullah , Al Malki Sharouq , Al Ansari Abdulrahman Saleh
Published: April 2024

This study employs copula functions to establish the dependency structure of the joint distribution among rainfall intensity, wind speed, and wind direction in Qatar. Based on a Vine Copula, the trivariate distribution between rainfall intensity, wind speed, and wind direction is found to exhibit a root-mean-square error (RMSE) of 0.0072 on the observed vs. modeled cumulative probabilities using ranked normalized observations. It is also found that the winter Shamal winds are most pronounced during rainfall. However, a secondary component of easterly winds known as the Kaus winds is also found to exert an important influence. This wind pattern is observable during rainfall at all the selected stations, albeit with minor variations. It is also found that rainfall stations where the rainfall is obstructed in any way from northwest to north and from east to southeast significantly influence the rainfall measurements. Specific rain gauges in Qatar are found to be situated in disrupted surroundings, such as meteorological stations close to passing traffic, where road spray could infiltrate the rain gauge funnel, impacting the accuracy of rainfall measurements. The study results necessitated the relocation of approximately half of these roadside gauges to mitigate wind-induced biases from road spray. An evaluation of operations is recommended for approximately 80 meteorological stations responsible for measuring rainfall in Qatar. The methodology devised in this study holds potential for application to other Middle Eastern countries and regions with similar climates.
Burst Diagnosis Multi-Stage Model for Water Distribution Networks Based on Deep Learning Algorithms
Authors: Peng Sen , Wang Yuxin , Fang Xu , Wu Qing
Published: April 2024

Pipe bursts in water distribution networks (WDNs) pose significant threats to the safety of distribution networks, driving attention to deep learning-based burst detection and localization. However, the applicability of different pressure features still needs to be compared and verified. A large number of nodes challenges deep learning with the excessive number of classification categories and low recognition accuracy. To address these problems, this paper extracts different burst pressure features, including pressure value, pressure difference, and pressure fluctuation ratio, and inputs one of these features into a Burst Diagnosis Multi-Stage Model (BDMM) based on three CS-LSTMs (a combination of the Cuckoo Search algorithm and a long short-term memory network). The first model addresses a binary classification problem, outputting labels indicating whether a pipe burst has occurred. The second one solves a multi-classification problem, outputting the label of the burst partition, and the third model also solves a multi-classification problem, outputting the ID of the bursting junction. The model is tested on a real network and outperforms ELM. For basic burst identification tasks using CS-LSTM, differences among the three features are minimal, while pressure difference and pressure fluctuation ratio exhibit superior performance to pressure value when resolving more complex problems like burst junction localization.
Changes in Surface Water Quality of the El Salvador River in La Joya de los Sachas, Ecuadorian Amazon Region
Authors: Vargas-Tierras Tannia , Jiménez-Gutiérrez Mirian , Pastrano Sandra , Chávez Gino , Morales-León Vanessa , Morales-León María , Paredes Fernando , Vásquez-Castillo Wilson
Published: April 2024

Water effluent pollution in the Ecuadorian Amazon occurs mainly due to the lack of sewage infrastructure, wastewater treatment plants in urban and rural areas, and agricultural and livestock activities. Consequently, understanding water quality is crucial because of its dynamic nature, influenced by various activities along its course. We evaluated and compared the water quality status of the El Salvador River with the current standards of the Ministry of the Environment, Water, and Ecological Transition in Ecuador and with Decree No. 115/2003 on water quality and water pollution management. The water quality index was determined through random sampling at seven locations along the river. The results show good water quality, with contamination indices ranging from 84 to 87. When comparing the results with the standards, all water quality parameters met the standards for recreational purposes. However, considering the river’s uses for agricultural activities, we compared the water with additional standards from legislation outlined by the Environment Ministry and found that the nitrate content exceeded permissible limits due to runoff from the surrounding crops, causing a potential risk to human health. Therefore, incorporating helophyte plants is a promising option that would promote the health of this aquatic ecosystem and others.
Analyzing the Seasonal Vertical Displacement Fluctuations Using the Global Navigation Satellite System and Hydrological Load: A Case Study of the Western Yunnan Region
Authors: Xu Pengfei , Jiang Tao , Li Wanqiu , Xu Gong , Zhang Chuanyin , Wang Wei , Tian Kunjun , Feng Jiandi
Published: April 2024

The non-tectonic deformation caused by hydrological loads is an important influencing factor in GNSS vertical displacement. Limited by the temporal and spatial resolution of global models and model errors, the hydrological load results calculated by traditional methods are difficult to meet the high temporal and spatial resolution requirements of small to medium-scale regions. This paper introduces the idea of the remove–restore method, assimilates regional high-resolution hydrological data, and obtains higher temporal and spatial-resolution hydrological load results. Subsequently, utilizing data from 12 CORS observed in the western Yunnan region between January 2018 and December 2020, the quantitative relationship and variation characteristics between GNSS vertical displacement and hydrological load displacement were analyzed in detail. Furthermore, the annual signals of both were extracted using the SSA method for comparative analysis. After removing the effects of atmospheric load and non-tidal ocean load, the average correlation coefficient between GNSS vertical displacement and hydrological load displacement is 0.84, with an average reduction of WRMS (%) reaching 37.17%. The average correlation coefficient of the annual signals between GNSS vertical displacement and hydrological load deformation is 0.94, with an average reduction of WRMS (%) reaching 46.5%, indicating that the contribution of hydrological load to the GNSS non-tectonic vertical displacement annual signal is close to 50%. The research results provide scientific support and important references for studying surface tectonic deformation by removing non-tectonic deformations such as hydrological loads from GNSS vertical displacement. Additionally, it helps to explore the mechanisms of interaction between water storage migration and surface deformation.
Determining the Relevance of Commonly Used Hydraulic Parameters for Representing the Water Erosive Force in Rock Mass Erosion within Dam Spillways
Authors: Koulibaly Aboubacar Sidiki , Saeidi Ali , Rouleau Alain , Quirion Marco
Published: April 2024

Spillways are essential control structures in hydroelectric dams for evacuating excess water during periods of high-water flow. These structures are generally excavated within a rock mass, without lining, and they take the form of a flow channel or a plunge pool. Rock mass erosion is an important issue facing engineers when designing unlined spillways. Methods commonly used to analyze this phenomenon are based on the threshold line concept, i.e., the correlation between rock mass resistance and its destruction against the erosive force of water. Multiple indices have been proposed for both rock mass quality and water energy (or erosive force) to assess rock mass erosion. The selection of appropriate indices is critical when evaluating hydraulic erosion. The erosive force of water is often represented by energy dissipation; however, other parameters, including average flow velocity and shear stress at the bottom of the flow channel, may also be relevant. Thus, a critical question is framed: which index best represents the erosive force of water? Here, we develop an approach to assess the applicability of the various indices used to represent the erosive force of water by relying on erosional events at more than 100 study sites. We determine that the most relevant parameters are linked to water pressure, as pressure head and flow velocity better explain the erosive force of the water than shear stress and water dissipation energy.
Unraveling the Coupled Dynamics between DOM Transformation and Arsenic Mobilization in Aquifer Systems during Microbial Sulfate Reduction: Evidence from Sediment Incubation Experiment
Authors: Du Xingguo , Li Hui , Jiang Yue , Yuan Jianfei , Zheng Tianliang
Published: April 2024

Geogenic arsenic (As)-rich groundwater poses a significant environmental challenge worldwide, yet our understanding of the interplay between dissolved organic matter (DOM) transformation and arsenic mobilization during microbial sulfate reduction remains limited. This study involved microcosm experiments using As-rich aquifer sediments from the Singe Tsangpo River basin (STR) and Jianghan Plain (JHP), respectively. The findings revealed that microbial sulfate reduction remarkably increased arsenic mobilization in both STR and JHP sediments compared to that in unamended sediments. Moreover, the mobilization of As during microbial sulfate reduction coincided with increases in the fluorescence intensity of two humic-like substances, C2 and C3 (R = 0.87/0.87 and R = 0.73/0.66 in the STR and JHP sediments, respectively; p < 0.05), suggesting competitive desorption between DOM and As during incubation. Moreover, the transformations in the DOM molecular characteristics showed significant increases in CHOS molecular and low-O/C-value molecular intensities corresponding to the enhancement of microbial sulfate reduction and the possible occurrence of methanogenesis processes, which suggests a substantial bioproduction contribution to DOM components that is conducive to As mobilization during the microbial sulfate reduction. The present results thus provide new insights into the co-evolution between As mobilization and DOM transformations in alluvial aquifer systems under strong microbial sulfate reduction conditions.
Spatial Distribution and Seasonal Variation of Antibiotic-Resistant Bacteria in an Urban River in Northeast China
Authors: Xiao Qingshan , Wang Xin , Xu Chongxin , Chen Wei , Huang Qianchi , Wang Xin
Published: April 2024

As the largest freshwater river flowing through Harbin, the Songhua River is a standby water source. It is very important to know the species and distribution of antibiotic-resistant bacteria (ARB) in the river. In this study, five antibiotics were selected to screen and identify ARB in spring and autumn. The results showed that the concentration of cefotaxime-resistant bacteria was the highest, and the maximum concentration at S6 in spring was up to 1.40 × 104 CFU/mL. In spring and autumn, bacteria resistant to three antibiotics were screened at S1 of the Songhua River, and bacteria resistant to five antibiotics were screened at S6. No multiple antibiotic-resistant bacteria (MARB) were screened in the other four sites in autumn, while MARB were screened in the other three samples except S2 in spring. In all sample areas in spring and autumn, the probability of screening MARB at S1 and S6 was the highest, reaching 100%. The identification results of 16S rDNA polymerase chain reaction (PCR) products of ARB showed that a total of 51 ARB strains from 15 bacterial genera were screened in the Songhua River, of which 20 ARB strains were from Pseudomonas. Among the 15 bacterial genera, bacteria from 8 bacterial genera have pathogenicity. The results of this study revealed the concentration, spatial distribution, and seasonal variation of culturable ARB in the Songhua River, providing data support for the remediation of antibiotic resistance gene (ARG) pollution in the river.
Spatial and Temporal Distribution Characteristics and Potential Sources of Microplastic Pollution in China’s Freshwater Environments
Authors: He Hualong , Cai Sulin , Chen Siyuan , Li Qiang , Wan Pengwei , Ye Rumeng , Zeng Xiaoyi , Yao Bei , Ji Yanli , Cao Tingting , Luo Yunchao , Jiang Han , Liu Run , Chen Qi , Fang You , Pang Lu , Chen Yunru , He Weihua , Pan Yueting , Pu Gaozhong , Zeng Jiaqin , Tian Xingjun
Published: April 2024

Microplastic pollution is a research hotspot around the world. This study investigated the characteristics of microplastic pollution in the freshwater environments of 21 major cities across China. Through indoor and outdoor experimental analysis, we have identified the spatial and temporal distribution characteristics of microplastic pollution in China’s freshwater environments. Our findings indicate that the average concentration of microplastics in China’s freshwater environments is 3502.6 n/m3. The majority of these microplastics are fibrous (42.5%), predominantly smaller than 3 mm (28.1%), and mostly colored (64.7%). The primary chemical components of these microplastics are polyethylene (PE, 33.6%), polyvinyl chloride (PVC, 21.5%), polypropylene (PP, 16.8%), and polystyrene (PS, 15.6%). The abundance of microplastics in China’s freshwater environments generally tends to increase from west to east and from south to north, with the lowest concentration found in Xining, Qinghai (1737.5 n/m3), and the highest in Jiamusi, Heilongjiang (5650.0 n/m3). The distribution characteristics of microplastics are directly related to land use types, primarily concentrated in areas of intense human activity, including agricultural, transport, and urban land. Seasonal changes affect the abundance of microplastics, peaking in summer, followed by spring and autumn, mainly due to variations in rainfall, showing a positive correlation.