bluuebunny/crossref_metadata_2025 huggingface dataset:
Impact of Rainfall Variability and Land Use Change on River Discharge in South Cameroon
Authors: Ebodé Valentin Brice , Braun Jean Jacques , Nnomo Bernadette Nka , Mahé Gil , Nkiaka Elias , Riotte Jean
Published: March 2022

Climate change, variability and anthropogenic forcings such as land use change are the main forcings of river discharge variability. However, an understanding of their simultaneous impacts on river discharge remains limited in some parts of the world. To shed light on this issue, the objective of this article is to investigate the effects of rainfall variability and land use change on river discharge in the Nyong basin (at Olama and Mbalmayo gauging stations) and some of its sub-basins (So’o and Mefou) over the long period 1950–2018. To achieve this goal, hydro-meteorological data of the Nyong basin and sub-basins were analyzed using the Pettitt test. Likewise, land use changes in the basin and sub-basins were also analyzed using supervised classifications of Landsat satellite images of the basins at different periods (1973, 2000 and 2018). On the annual scale, rainfall has decreased statistically over the studied basins. In the large basins (Olama and Mbalmayo), this decrease in rainfall is synchronous with that of discharges, while it is concomitant with an increase in the Mefou (small basin). After the ruptures within time series identified in the annual modules, the extreme discharges (maximum and minimum) decreased in Olama; in Mbalmayo, the maximum discharges remained stable while the minimum discharges decreased. On the other hand, the maximum and minimum discharges have significantly increased in the Mefou. The stability of maximum discharges at Mbalmayo and the increase in extremes on the Mefou in a context where the precipitation that generates the discharge has decreased can be attributed to land use change. These changes are essentially marked by an increase in impervious areas and a reduction in forest cover. On the seasonal scale, the impact of precipitation in the dry season is visible on the flows of the rainy seasons that follow them on the large basins (Olama and Mbalmayo). Between the decades 1970–1990 and 2000–2010, there was respectively a significant increase, then a decrease in summer precipitation, which impacted the autumn discharges in the same direction. Conversely, between the same intervals, there was a significant decrease, then a slight increase in winter precipitation. The impact of winter precipitation on the spring discharge is more visible during the first period only (1970–1990). During the second period, winter precipitation seems to have more of an impact on the runoff for the same season. In the Mefou sub-basin, the precipitation plays an essentially amplifying role in the increase in discharge in the seasons during which they occur. Those having experienced an increase, or a maintenance of precipitation (summer and spring) recorded the most significant increases in discharges. These results could be useful for long-term planning on the demand and use of water, as well as flood management in the basins
Estimating Optimal Design Frequency and Future Hydrological Risk in Local River Basins According to RCP Scenarios
Authors: Ryu Jae-Hee , Kim Ji-Eun , Lee Jin-Young , Kwon Hyun-Han , Kim Tae-Woong
Published: March 2022

In South Korea, flood damage mainly occurs around rivers; thus, it is necessary to determine the optimal design frequency for river basins to prevent flood damage. However, there are not enough studies showing the effect of climate change on hydrologic design frequency. Therefore, to estimate the optimal design frequency according to future climate change scenarios, this study examined urban flooding area and extreme rainfall frequency that can change in the future. After estimating the optimal design frequency, hydrological risks of 413 local river basins were evaluated according to Representative Concentration Pathway (RCP) scenarios 4.5 and 8.5 after regenerating daily rainfalls from the HadGEM2-ES model into hourly rainfalls using the Poisson cluster. For the RCP 4.5, hydrological risks increased relative to the established design frequency by 3.13% on average. For the RCP 8.5, hydrological risks increased by 2.80% on average. The hydrological risks increased by 4.58% in the P2(2040–2069) period for the RCP 4.5, and by 4.39% in the P1 (2021–2039) period for the RCP 8.5. These results suggest that the hydrologic design frequency in the future will likely decrease, and the safety of river basins will also decrease.
Assessment of Reed Grasses (Phragmites australis) Performance in PFAS Removal from Water: A Phytoremediation Pilot Plant Study
Authors: Ferrario Claudia , Peruzzi Cosimo , Cislaghi Alessio , Polesello Stefano , Valsecchi Sara , Lava Roberto , Zanon Francesca , Santovito Gianfranco , Barausse Alberto , Bonato Marco
Published: March 2022

Per- and polyfluoroalkyl substances (PFASs) have multiple emission sources, from industrial to domestic, and their high persistence and mobility help them to spread in all the networks of watercourses. Diffuse pollution of these compounds can be potentially mitigated by the application of green infrastructures, which are a pillar of the EU Green Deal. In this context, a phytoremediation pilot plant was realised and supplied by a contaminated well-located in Lonigo (Veneto Region, Italy) where surface and groundwaters were significantly impacted by perfluoroalkyl acids (PFAAs) discharges from a fluorochemical factory. The investigation involved the detection of perfluorobutanoic acid (PFBA), perfluorooctanoic acid (PFOA), perfluorobutanesulfonic acid (PFBS) and perfluorooctanesulfonic acid (PFOS) inside the inlet and outlet waters of the phytoremediation pilot plant as well as in reed grasses grown into its main tank. The obtained results demonstrate that the pilot plant is able to reduce up to 50% of considered PFAAs in terms of mass flow without an evident dependence on physico-chemical characteristics of these contaminants. Moreover, PFAAs were found in the exposed reed grasses at concentrations up to 13 ng g−1 ww. A positive correlation between PFAA concentration in plants and exposure time was also observed. In conclusion, this paper highlights the potential efficiency of phytodepuration in PFAS removal and recommends improving the knowledge about its application in constructed wetlands as a highly sustainable choice in wastewater remediation.
Multi-Expression Programming (MEP): Water Quality Assessment Using Water Quality Indices
Authors: Aldrees Ali , Khan Mohsin Ali , Tariq Muhammad Atiq Ur Rehman , Mustafa Mohamed Abdeliazim , Ng Ane Wai Man , Bakheit Taha Abubakr Taha
Published: March 2022

Water contamination is indeed a worldwide problem that threatens public health, environmental protection, and agricultural productivity. The distinctive attributes of machine learning (ML)-based modelling can provide in-depth understanding into increasing water quality challenges. This study presents the development of a multi-expression programming (MEP) based predictive model for water quality parameters, i.e., electrical conductivity (EC) and total dissolved solids (TDS) in the upper Indus River at two different outlet locations using 360 readings collected on a monthly basis. The optimized MEP models were assessed using different statistical measurements i.e., coefficient-of-determination (R2), root-mean-square error (RMSE), mean-absolute error (MAE), root-mean-square-logarithmic error (RMSLE) and mean-absolute-percent error (MAPE). The results show that the R2 in the testing phase (subjected to unseen data) for EC-MEP and TDS-MEP models is above 0.90, i.e., 0.9674 and 0.9725, respectively, reflecting the higher accuracy and generalized performance. Also, the error measures are quite lower. In accordance with MAPE statistics, both the MEP models shows an “excellent” performance in all three stages. In comparison with traditional non-linear regression models (NLRMs), the developed machine learning models have good generalization capabilities. The sensitivity analysis of the developed MEP models with regard to the significance of each input on the forecasted water quality parameters suggests that Cl and HCO3 have substantial impacts on the predictions of MEP models (EC and TDS), with a sensitiveness index above 0.90, although the influence of the Na is the less prominent. The results of this research suggest that the development of intelligence models for EC and TDS are cost effective and viable for the evaluation and monitoring of the quality of river water.
Research on Water Resources Allocation System Based on Rational Utilization of Brackish Water
Authors: Zhang Dasheng , Xie Xinmin , Wang Ting , Wang Boxin , Pei Shasha
Published: March 2022

The rational utilization of unconventional water sources is of great significance to areas where conventional water resources are scarce, and water resource allocation is an important way to realize the rational distribution of multiple water sources. This paper constructs a water resources allocation system integrating model data parameter database, water resources supply and demand prediction module, groundwater numerical simulation module and water resources allocation module. Taking brackish water as the main research object and final goal of achieving the best comprehensive optimization of social, economic and ecological benefits. The brackish water is incorporated as an independent water source into the water resource allocation model, and the stratum structure model and groundwater numerical model are constructed to simulate the brackish water level in the planning target year. The water resources allocation system is applied to Guantao County, China. The results show that increasing the development and utilization of brackish water under the recommended scheme can significantly reduce the water supply pressure of local fresh water resources in agriculture and industry. Compared with the current year, the overall water shortage in the region will be reduced by 4.493 × 106 m³ in 2030, and meanwhile, the brackish water level will be decreased by 12.69 m in 2035, which plays a positive role in improving soil salinization.
Integration of a Shallow Soda Lake into the Groundwater Flow System by Using Hydraulic Evaluation and Environmental Tracers
Authors: Baják Petra , Hegedűs-Csondor Katalin , Tiljander Mia , Korkka-Niemi Kirsti , Surbeck Heinz , Izsák Bálint , Vargha Márta , Horváth Ákos , Pándics Tamás , Erőss Anita
Published: March 2022

Lake Velence is a shallow soda lake whose water level and water quality show a severely deteriorating tendency in recent years. Until recently, the groundwater component in the lake’s water budget has not been taken into consideration. To integrate the lake into the groundwater flow system at the regional scale, methods of “basin hydraulics” were applied. In addition, 17 water samples were collected for δ2H and δ18O, and for ΣU, 226Ra and 222Rn activity measurements to use these parameters as environmental tracers of groundwater contribution. Groundwater mapping revealed that groundwater recharges in Velence Hills and the local elevations south of the lake, whereas discharge occurs by the lake’s shoreline and along surface watercourses. The results indicated that Lake Velence is the discharge point of local groundwater flow systems known to be more sensitive to climate changes and anthropogenic activities (e.g., contamination, overexploitation). Groundwater and lake water have similar uranium activity concentrations serving as another sign of groundwater inflow into the lake. Therefore, it is necessary to consider both the groundwater component in the lake’s water management and its vulnerability regarding local and short-term changes in the catchment area.
Numerical Simulation of Fluid Pore Pressure Diffusion and Its Mechanical Effects during Wenchuan Aftershocks
Authors: Chen Tao , Liu Yaowei , Zhang Guomeng
Published: March 2022

The Ms 8.0 Wenchuan earthquake occurred on 12 May 2008, in the Sichuan Province of China, and it was accompanied by a series of strong aftershocks. The mechanisms contributing to the triggering of the Wenchuan aftershocks have attracted international attention. In this paper, based on previous analysis of spatiotemporal distribution of aftershocks regarding pore pressure diffusion of deep fluid, we established a three-dimensional hydraulic–mechanical coupling model and investigated the influence of fluid migration and its mechanical effects in the Longmenshan fault zone by using FLAC3D software. We obtained the characteristics of the pore pressure diffusion and fault reactivation within 70 days in an area NA. The results show that the pore pressure significantly increases up to 80 MPa during fluid intrusion into the fault plane. The pore pressure increase along the fault dip is greater than that along the fault strike, with a maximum difference of 3.18 MPa. The increase in pore pressure along the fault reduces the effective stress and leads to fault reactivation. The evolution of the fault reactivation area calculated in the model is compared with the spatiotemporal characteristics of the aftershocks. This study is meaningful for furthering the understanding of the role of deep fluids in fault dynamics and aftershocks triggering.
Soil Water Use Strategies of Dominant Tree Species Based on Stable Isotopes in Subtropical Regions, Central China
Authors: Li Yuchen , Zhu Fangfang , Wang Yu , Cheng Jinhua
Published: March 2022

Water is a crucial factor affecting plant growth and ecosystem processes. In the subtropical region, global climate change leads to frequent seasonal droughts. How plant water strategies and the adaptability of forest ecosystems change is an urgent issue to be discussed. In this study, four sample plots (P. massoniana for Plot 1, C. lanceolata for Plot 2, Q. acutissima for Plot 3, C. funebris and I. corallina for Plot 4) were selected in the Taizishan Mountain area of Hubei, China, including three forest types (coniferous forest, broad-leaved forest and coniferous broad-leaved mixed forest) and five dominant tree species. The δD and δ18O isotope compositions in plant and soil water were analysed, and the water use strategies of dominant species were predicted by using the MixSIAR model. The water absorption depth and proportion of the five species were significantly different in different seasons. In plot 4, I. corallina and C. funebris derived (58.8 ± 14.0% and 55.7 ± 23.4%, respectively) water from 10–40 cm soil in wet season, but C. funebris shifted to derive water from deep soil in dry season. This result indicates that the mixing of C. funebris and I. corallina can effectively prevent water competition in dry season with water deficit. From wet season to dry season, the depth of water utilisation of the P. massoniana, C. lanceolata, Q. acutissima and C. funebris with deep roots converted from shallow to deep soil, suggesting that the four species had significant dimorphic root systems and strong ecological plasticity.
Physical Experimentation and 2D-CFD Parametric Study of Flow through Transverse Bottom Racks
Authors: Carrión-Coronel Eduardo , Ortiz Pablo , Nanía Leonardo
Published: March 2022

In the present study, the hydraulic operation of flow through transverse bottom racks screens with conventional triangular wedge wire and alternative circular section wire is experimentally and numerically analyzed. A laboratory prototype is built for experimentation with clean water and sediment. The numerical experiment is developed with the Ansys Fluent software, and a 2D CFD parametric study is designed to evaluate the influence on the captured flow of geometric variables, such as the screen incline, position of the screen along the channel (top, middle, bottom), and shape, wire width, or slot width. The physical model results make it possible to determine the efficiency of the screens in terms of collection capacity and sediment removal. In contrast, numerical experimentation determines the influence of geometric variables on the collection flow. The flows captured by each screen slot are determined numerically. The trends of the total flows captured are determined, and the performance of each studied screen type is assessed using the relevant non-dimensional parameters.
Determination of the Habitat Preferences of Dominant Epilithic Diatoms Using Statistical Models: A Case Study in the Han River, South Korea
Authors: Shin Yuna , Kim Doyun , Heo Tae-Young
Published: March 2022

Diatoms have traditionally been used to assess water quality; however, current research suggests that physical factors, such as habitat and landscape, may be linked to the organization of diatom assemblages in streams. The aim of this study was to determine the environmental factors affecting the physiological and ecological changes of epilithic diatoms. To this end, the dominant diatom species were used, and a strategy based on epilithic diatom habitat characteristics was investigated for river restoration. The classification and regression tree (CART) and weighted averaging (WA) regression models were used to determine the habitat preference of epilithic diatoms and physicochemical environmental factors. The 35 environmental variables and six epilithic diatom species that were dominant at 58 sites along the Han River in South Korea were used. The species abundance and composition of adherent diatoms were affected by nutrient concentration and a variety of physicochemical environmental factors. These results suggest that when evaluating water quality, various factors that affect the abundance of epilithic diatoms should be considered. Research on the autecological characteristics and environmental preferences of indicator diatom species could help establish river restoration policies and quantitative evaluation criteria for biological assessments.
Aeration Biofilter Filler Screening and Experimental Research on Nitrogen and Phosphorus Purification in Rural Black Water
Authors: Chen Peizhen , Chen Dongkai , Zhao Wenjie , Zheng Xiangqun
Published: March 2022

In rural toilets, black water still remains polluted by nitrogen and phosphorus after being pre-treated by septic tanks. This study uses aerated biofilters to purify black water, screen the biofilter filler, and determine its effect on nitrogen and phosphorus purification in rural black water. This study introduced the concept of the “shape factor” into the Langmuir and Freundlich equations and optimized the isotherm adsorption model to better fit the actual dynamics of nitrogen and purification in black water. Combined with the first-order kinetic equation, the double constant equation, and the Elovich equation, the adsorption performance of seven kinds of biofilter fillers (i.e., zeolite, volcanic rock, sepiolite, ceramsite, anthracite, vermiculite, and peat) was studied. Then, the biofilter was constructed using a combination of fillers with better adsorption properties, and its ability to purify rural black water was studied. Results showed that vermiculite and zeolite had little effect on nitrogen and a high saturated adsorption of 654.50 and 300.89 mg·kg−1, respectively; peat and ceramsite had little effect on phosphorus and a high saturated adsorption of 282.41 mg·kg−1 and 233.89 mg·kg−1, respectively. The adsorption rate of nitrogen from fast to slow was vermiculite > peat > zeolite > volcanic rock > sepiolite > ceramsite > anthracite. The adsorption rate of phosphorus from fast to slow was peat > ceramsite > zeolite > sepiolite > vermiculite > volcanic rock > anthracite. Four combined biological filter fillers aided the removal of nitrogen and phosphorus from rural high-concentration black water. The combination of zeolite and ceramsite filler had a good nitrogen and phosphorus removal effect in high-concentration black water. After the system was stable, the nitrogen removal rate attained 71–73%, and the phosphorus removal rate attained 73–76% under the influent condition of total nitrogen and phosphorus concentrations of 150–162 and 10–14 mg·L−1, respectively. This study provides technical support and reference for the purification and treatment of rural black water.
Dimensional Analysis Model of Head Loss for Sand Media Filters in a Drip Irrigation System Using Reclaimed Water
Authors: Hu Yaqi , Wu Wenyong , Liu Honglu , Huang Yan , Bi Xiangshuai , Liao Renkuan , Yin Shiyang
Published: March 2022

A new model was developed to predict head loss in sand media filters. Sand filters with six different media using reclaimed water were used to measure head losses at different flow rates in the laboratory. The parameters influencing head losses were considered to be the uniformity coefficient, the effective diameter, the sand mass, the filtration velocity, the pollution load, and the water viscosity. A dimensional analysis method was used to develop the model. A comparison between the predicted and the measured head losses showed close agreement with a correlation coefficient of 91.7%, reaching a significance level of p < 0.001. The results showed that the model might give satisfactory predictions within the following range of operational and filter structure parameters: uniformity coefficient 1.48–3.31; effective diameter 0.41–2.1 mm; pollution load 0.0169–4.2049 kg, filtration velocity 0.0038–0.0398 m/s.
A Sink Screening Approach for 1D Surface Network Simplification in Urban Flood Modelling
Authors: Zhao Guohan , Mark Ole , Balstrøm Thomas , Jensen Marina B.
Published: March 2022

Sinks configure the surface networks for overland flow processes representations during 1D hydrodynamic modelling. The excessive number of sinks detected from high-resolution DEMs can boost 1D computational costs significantly. To pursue optimal sink numbers and their optimal spatial distribution, a Volume Ratio Sink Screening (VRSS) method was developed to screen for computationally important sinks, while compensating for volume losses from removed (unimportant) sinks, such that 1D hydrodynamic modelling yields faster computing times without significant loss of accuracy. In comparison with an existing geometry-based sink screening method, we validated this method by conducting sensitivity analyses for the proposed screening criteria in three Danish case areas of distinct topographies. Two iterative procedures were programmed to assess and compare their sink screening performances in terms of sink number reductions and volume loss reductions, and a volume loss solver was developed to quantify catchment-wide volume losses in the 1D surface network. Compared to a geometry-based sink screening method, the VRSS method performs more robustly and produces more efficient reductions in the number of sinks, as well as efficient reductions in volume losses.
Hydrogeochemical Characteristics Refine the Conceptual Model of Groundwater Flow in Wood Buffalo National Park, Canada
Authors: Déri-Takács Judit , Rostron Benjamin , Mendoza Carl , Mádl-Szőnyi Judit
Published: March 2022

Wood Buffalo National Park (WBNP), the largest national park of Canada, has unique and complex ecosystems that depend on specific water quantity and quality. We characterize groundwaters and surface waters in WBNP by determining their chemical compositions and water types, the dominant hydrochemical processes affecting their compositions, and their hydrochemical characteristics in relation to interpreted groundwater flow systems. Total Dissolved Solid concentrations in groundwaters and surface waters range from ≤10 mg/L to ≥300,000 mg/L. Four distinct water type groups are found: (1) Ca-SO4-type waters occur in multiple clusters across the area in outcrop areas of Devonian evaporites; (2) Na-Cl-type waters predominantly occur in the Salt plains region along the central eastern boundary, overlapping evaporite and carbonate-dominated bedrock formations; (3) Ca-HCO3-type waters dominate the Peace-Athabasca Delta-region in the south and most of the central region; and (4) “mixed” waters. Solutes in the waters originate from three main processes: dissolution of halite, dissolution of sulphate minerals, and dissolution of carbonates. The spatial occurrence of hydrochemical characteristics correlate with hypothesized groundwater flow systems, i.e., Ca-SO4 and Na-Cl-type waters coincide with discharge areas of intermediate to regional groundwater flow paths, and Ca-HCO3-type waters overlap with recharge areas. The findings of this study contribute to advancing knowledge on the hydrochemical characteristics of this remote and highly protected region of Alberta, Canada, and are important components of any further, comprehensive assessment of the natural water conditions.
Global-Scale Assessment of Economic Losses Caused by Flood-Related Business Interruption
Authors: Taguchi Ryo , Tanoue Masahiro , Yamazaki Dai , Hirabayashi Yukiko
Published: March 2022

Estimating river flood risk helps us to develop strategies for reducing the economic losses and making a resilient society. Flood-related economic losses can be categorized as direct asset damage, opportunity losses because of business interruption (BI loss), and high-order propagation effects on global trade networks. Biases in meteorological data obtained from climate models hinder the estimation of BI loss because of inaccurate input data including inundation extent and period. In this study, we estimated BI loss and asset damage using a global river and inundation model driven by a recently developed bias-corrected meteorological forcing scheme. The results from the bias-corrected forcing scheme showed an estimated global BI loss and asset damage of USD 26.9 and 130.9 billion (2005 purchase power party, PPP) (1960–2013 average), respectively. Although some regional differences were detected, the estimated BI loss was similar in magnitude to reported historical flood losses. BI loss tended to be greater in river basins with mild slopes such as the Amazon, which has a long inundation period. Future flood risk projection using the same framework under Representative Concentration Pathway 8.5 (RCP8.5) and Shared Socioeconomic Pathway 3 (SSP3) scenarios showed increases in BI loss and asset damage per GDP by 0.32% and 1.78% (2061–2090 average) compared with a past period (1971–2000 average), respectively.
Sequence Analysis of Ancient River Blocking Events in SE Tibetan Plateau Using Multidisciplinary Approaches
Authors: Zhang Yiwei , Chen Jianping , Wang Qing , Li Yongchao , Song Shengyuan , Gu Feifan , Cao Chen
Published: March 2022

The temporary or permanent river blocking event caused by mass movement usually occurs on steep terrain. With the increase of mountain population and land use pressure and the construction of water conservancy and hydropower projects, river blocking events have gradually attracted people’s attention and understanding. The area in this study is affected by strong tectonic activity in the Jinsha River suture zone and the rapid uplift of the Tibetan Plateau. In the past 6000 years, there have been at least five obvious river blocking events in the reach. The number and density are very rare. Combining field investigation, indoor interpretation, laboratory tests, optically stimulated luminescence (OSL) dating, SBAS-InSAR and previous studies, multidisciplinary approaches are used to systematically summarize the analysis methods and further the understanding of one river blocking event and multiple river blocking events from different perspectives. Especially in multiple river blocking events, we can get the wrong results if interaction is not considered. Through this study, the general method of analyzing the river blocking event and the problems that should be paid attention to in sampling are given, and relatively reliable historical results of river blocking events are obtained. This method has applicability to the identification and analysis of river blocking events and age determination of dams with multiple river blockages.
The Effects of Contrast between Dark- and Light-Coloured Tanks on the Growth Performance and Antioxidant Parameters of Juvenile European Perch (Perca fluviatilis)
Authors: Molnár Áron , Homoki Dávid Zoltán , Bársony Péter , Kertész Attila , Remenyik Judit , Pesti-Asbóth Georgina , Fehér Milán
Published: March 2022

European perch (Perca fluviatilis) is a predatory fish species with a high degree of stress sensitivity during rearing in intensive systems. Our study was focused on the effects of contrast between two colours (black and light grey) in different parts of a tank (bottom and sidewall) on the production and antioxidant parameters of juvenile European perch during intensive rearing. The duration of the experiment was 8 weeks. In the first treatment, the bottoms of the tanks were black (DB); in the second treatment, the sides of the tank were black (DS); in the control treatment, the fish were kept in light-grey tanks (K). There were three replicates per treatment, and a total of 180 individuals were used; therefore, 60 individuals were used per treatment, with 20 individuals per tank. The mean body weight of the fish at the start of the experiment was 32.01 ± 0.79 g. At the end of the experiment, the antioxidant parameters (cortisol, glucose, MDA, catalase, vitamin C, GPx, GR, GSH, GSSG, and HSP70) of the fish were determined from blood samples. The results of our experiment show that different levels of contrast between the dark and light tank colours significantly influenced the production and antioxidant parameters of the juvenile European perch.
Greenhouse Gases Trade-Off from Ponds: An Overview of Emission Process and Their Driving Factors
Authors: Malyan Sandeep K. , Singh Omkar , Kumar Amit , Anand Gagan , Singh Rajesh , Singh Sandeep , Yu Zhiguo , Kumar Jhlaesh , Fagodiya Ram K. , Kumar Amit
Published: March 2022

Inland water bodies (particularly ponds) emit a significant amount of greenhouse gases (GHGs), particularly methane (CH4), carbon dioxide (CO2), and a comparatively low amount of nitrous oxide (N2O) to the atmosphere. In recent decades, ponds (<10,000 m2) probably account for about 1/3rd of the global lake perimeter and are considered a hotspot of GHG emissions. High nutrients and waterlogged conditions provide an ideal environment for CH4 production and emission. The rate of emissions differs according to climatic regions and is influenced by several biotic and abiotic factors, such as temperature, nutrients (C, N, & P), pH, dissolved oxygen, sediments, water depth, etc. Moreover, micro and macro planktons play a significant role in CO2 and CH4 emissions from ponds systems. Generally, in freshwater bodies, the produced N2O diffuses in the water and is converted into N2 gas through different biological processes. There are several other factors and mechanisms which significantly affect the CH4 and CO2 emission rate from ponds and need a comprehensive evaluation. This study aims to develop a decisive understanding of GHG emissions mechanisms, processes, and methods of measurement from ponds. Key factors affecting the emissions rate will also be discussed. This review will be highly useful for the environmentalists, policymakers, and water resources planners and managers to take suitable mitigation measures in advance so that the climatic impact could be reduced in the future.
Diversity and Vertical Distribution of Sedimentary Bacterial Communities and Its Association with Metal Bioavailability in Three Distinct Mangrove Reserves of South China
Authors: Hu Bochao , Liao Junxian , Zhang Qijiong , Ding Suli , He Mengyuan , Qiao Yue , Zhang Zuye , Shang Chenjing , Chen Si
Published: March 2022

The structure of sedimentary bacterial communities in mangroves depends on environmental factors such as pH, salinity, organic matter content, and metal pollution. To investigate the effect of heavy metal pollution on such communities, core samples of sediments from four sites in three distinct mangrove reserves (Golden Bay Mangrove Reserve in Beihai, Guangxi province (GXJHW), Shankou Mangrove Reserve in Hepu, Guangxi province (GXSK), and MaiPo mangrove in Hong Kong (MPCT and MPFQ)) in South China were analyzed for physicochemical properties, multiple chemical forms of metals, and vertical bacterial diversity. Sedimentary bacterial communities varied greatly among the different sampling sites, with biodiversity decreasing in the order of GXSK, GXJHW, MPFQ, and MPCT. Proteobacteria was the dominant phylum, followed by Chloroflexi, across all four sampling sites. Multivariate statistical analysis of the effect of environmental factors on the sedimentary bacterial communities found that total carbon was the only physicochemical factor with a significant influence at all four sites. The correlations between environmental factors and bacterial structure were weak for the two sites in Guangxi province, but strong at MPCT in Hong Kong where environmental factors were almost all significantly negatively correlated with bacterial diversity. Variance partitioning analysis revealed that physicochemical properties and chemical forms of metals could explain most of the changes in bacterial diversity. Overall, we observed that heavy metal forms were more important than total metal content in influencing the sedimentary bacterial diversity in mangroves, consistent with the more bioavailable metal species having the greatest effect.
Developing Predictive Equations for Water Capturing Performance and Sediment Release Efficiency for Coanda Intakes Using Artificial Intelligence Methods
Authors: Hazar Oğuz , Tayfur Gokmen , Elçi Sebnem , Singh Vijay P.
Published: March 2022

Estimation of withdrawal water and filtered sediment amounts are important to obtain maximum efficiency from an intake structure. The purpose of this study is to develop empirical equations to predict Water Capturing Performance (WCP) and Sediment Release Efficiency (SRE) for Coanda type intakes. These equations were developed using 216 sets of experimental data. Intakes were tested under six different slopes, six screens, and three water discharges. In SRE experiments, sediment concentration was kept constant. Dimensionless parameters were first developed and then subjected to multicollinearity analysis. Then, nonlinear equations were proposed whose exponents and coefficients were obtained using the Genetic Algorithm method. The equations were calibrated and validated with 70 and 30% of the data, respectively. The validation results revealed that the empirical equations produced low MAE and RMSE and high R2 values for both the WCP and the SRE. Results showed outperformance of the empirical equations against those of MNLR. Sensitivity analysis carried out by the ANNs revealed that the geometric parameters of the intake were comparably more sensitive than the flow characteristics.
Optimal Design of Water Treatment Contact Tanks
Authors: Aral Mustafa M.
Published: March 2022

In water treatment facilities, the last step of the treatment process includes disinfectant application to improve the water quality appropriate for a specific end-use purpose. At this step, contact tanks are used to mix water with the disinfectant. Mixing in contact tanks mainly relies on mechanical mixing processes to mix water with the disinfectant to activate the removal process. Thus, mixing efficiency of the contact tank design is critical for the reduction in the amount of disinfectant used to treat a fixed volume of water, to reduce the energy requirements to derive the treated volume of water through the system and to improve other design considerations of the contact tanks. There are numerous design alternatives reported in the literature that do achieve some of these purposes to a certain extent. Among the recent and more successful designs, one can cite the slot-baffle, the perforated-baffle, and the porous-baffle designs. Although these designs provide important improvements to the mixing process, the studies in which these concepts are reported did not provide an optimal design for the baffle geometry used in the design that would include other important considerations beyond the baffle geometry. In this paper, a new optimal design concept is introduced where important design considerations that are not considered in earlier studies are included in the analysis. The results show that new baffle geometries are possible for the optimal design of contact tanks when these innovative design criteria are included in the analysis.
Application of Saccharomyces cerevisiae in the Biosorption of Co(II), Zn(II) and Cu(II) Ions from Aqueous Media
Authors: Savastru Evgenia , Bulgariu Dumitru , Zamfir Cătălin-Ioan , Bulgariu Laura
Published: March 2022

Yeast biomass is considered a low-cost material that can be successfully used for the biosorption of metal ions from aqueous solution, due to its structural characteristics. This study evaluates the biosorptive performance of Saccharomyces cerevisiae in the biosorption of Co(II), Zn(II) and Cu(II) ions from aqueous media in batch mono-component systems. The influence of solution pH, biosorbent dose, contact time, temperature and initial metal ions concentration was examined step by step, to obtain the optimal conditions for biosorption experiments. Maximum uptake efficiency for all metal ions on this biosorbent was obtained at: pH = 5.0, 4.0 g biosorbent/L, room temperature of 23 °C, and a contact time of 60 min, and these were considered optimal. The equilibrium results were analyzed using Langmuir, Freundlich and Dubinin–Radushkevich isotherm models, while for the modeling of the kinetics data, three models (pseudo-first order, pseudo-second order and intra-particle diffusion) were used. Dubinin–Radushkevich isotherm model and the pseudo-second order model showed the best fit with the experimental data obtained at biosorption of Co(II), Zn(II) and Cu(II) ions on Saccharomyces cerevisiae. Both maximum biosorption capacities and pseudo-second rate constants follow the order: Co(II) > Zn(II) > Cu(II), suggesting that the structural particularities of metal ions are important in the biosorption processes. Based on the obtained equilibrium and kinetic parameters, the biosorption mechanism is analyzed and the possible applications are emphasized.
Co-Design for Enhancing Flood Resilience in Davao City, Philippines
Authors: Miyamoto Mamoru , Kakinuma Daiki , Ushiyama Tomoki , Rasmy Abdul Wahid Mohamed , Yasukawa Masaki , Bacaltos Della Grace , Sales Anthony C. , Koike Toshio , Kitsuregawa Masaru
Published: March 2022

Enhancing flood resilience, including the development of social capacity and early warning systems, in addition to structural measures, is one of the key solutions to mitigating flood damage, which will be more intensified in the future due to climate change. This study was conducted to develop a comprehensive methodology for enhancing flood resilience by improving society-wide disaster literacy under the governance formed through the active participation of all levels of stakeholders in Davao City, Philippines. Specifically, the development of the Online Synthesis System for Sustainability and Resilience, which integrates different disciplines, and the fostering of Facilitators, whose role is to interlink the science community and society, were implemented in a co-designing manner by the collective governance body. The development of basin- and barangay-scale hydrological models realized real-time flood forecasting and climate change impact assessment to identify intensified flood risk under the future climate. Co-designed e-learning workshops were held to foster about thirty Facilitators and help them produce twenty-one risk communication plans and workshop designs for fourteen barangays considering geographic, demographic, economic, and social features that they can utilize for public dissemination related to climate change adaptation to the target audiences in society. This paper presents a practical method to enhance flood resilience, demonstrating that the synthesis of science-based knowledge and human resource development can fill the gaps between the science community and society.
Sunflower Photosynthetic Characteristics, Nitrogen Uptake, and Nitrogen Use Efficiency under Different Soil Salinity and Nitrogen Applications
Authors: Ma Tao , Chen Kaiwen , He Pingru , Dai Yan , Yin Yiqun , Peng Suhan , Ding Jihui , Yu Shuang’en , Huang Jiesheng
Published: March 2022

Understanding salinity and fertilizer interaction is of great importance to improve crop production and fertilizer use efficiency in saline areas. To evaluate the interactive effects of different soil salinity levels and nitrogen (N) applications rates on the sunflower photosynthetic characteristics of N uptake and N use efficiency, a two-year field experiment was conducted in Hetao Irrigation District, China. The experiment consisted of three initial salinity (IS) levels expressed as the electrical conductivity of a saturated soil extract (ECe) (S0: 1.72–2.61 dS/m; S1: 4.73–5.90 dS/m; S2: 6.85–9.04 dS/m) and four N rates (45, 90, 135, and 180 kg/ha), referred as N0–N3, respectively. The results indicated that the net photosynthetic rate (Pn) of sunflowers treated with S0 and S1 levels both had a significant decrease in the bud stage, and then reached their maximum at anthesis. However, during the crop cycle, the Pn at S2 level only had small fluctuations and still remained at a high level (>40 μmol CO2/(m2 s)) at the early mature stage. When increasing IS levels from S0 to S1, the plant N uptake (PNU) under the same N rates were only decreased by less than 10% at maturity, whereas the decline was expanded to 17.2–45.7% from S1 to S2. Additionally, though applying the N2 rate could not increase sunflower PNU at the S0 and S1 levels, its N use efficiency was better than those under N3. Meanwhile, at the S2 level, the application of the N0 rate produced a higher N productive efficiency (NPE) and N uptake efficiency (NUPE) than the other N rates. Therefore, our study proposed recommended rates of N fertilizer (S0 and S1: 135 kg/ha, S2: 45 kg/ha) for sunflowers under different saline conditions.
Possibilies of multiple cervical fusion in degenerative pathology
Authors:   National Center for Rehabilitation and Prosthetics of the Disabled, Specialized Scientific and Practical Medical Center for Traumatology and Orthopedics of the Republic of Uzbekistan, Sattarov Alisher Rakhimovich , Shodmonov Bakhtiyor Rustamovich ,   National Center of Rehabilitation and Prosthetics of Disabled, Specialized Scientific and Practical Medical Center for Traumatology and Orthopedics of the Republic of Uzbekistan, Saidov Sohib Saidmurodovich ,   National Center of Rehabilitation and Prosthetics of Disabled, Specialized Scientific and Practical Medical Center for Traumatology and Orthopedics of the Republic of Uzbekistan, Boimurodov Gulomjon Abdugaffarovich ,   National Center of Rehabilitation and Prosthetics of Disabled, Specialized Scientific and Practical Medical Center for Traumatology and Orthopedics of the Republic of Uzbekistan
Published: March 2022

The aim of this study was to analyze treatment results of patients who underwent cervical fusion using cylindrical cage. 16 titanium cages were implanted to 12 patients with degenerative disease of cervical spine. Assessment of results was performed by neurologic examination, neurovisualization data, visual analogue pain scale. Mean duration of surgery was 45–90 min, blood loss — 30–60 ml, length of hospital stay — 4–6 days. Substantial decrease of frequency and intensity of neck and arm pain was observed after surgery in 89 % of patients. When properly performed, anterior cervical interbody fusion applying cylindrical cage is a simple and effective method.
Analysis of the staff situation at SBHI NR «Clinical Diagnostic Center»
Authors:   Institute of Nursing Education, Samara State Medical University of the Ministry of Healthcare of Russia, Pyreva Elena Vadimovna , Dvoynikov Sergey Ivanovich ,   Samara State Medical University of the Ministry of Healthcare of Russia
Published: March 2022

The purpose of the study is to analyze the human resources potential of specialists with secondary medical education in order to identify problems in the context of the spread of coronavirus infection. Results. when analyzing the staffing situation in the Clinical Diagnostic Center, a staff shortage of paramedical workerswas revealed, as evidenced by staffing rates, the ratio of medical and nursing staff and the part-time ratio. Conclusion. In the process of analytical activity, the following was revealed: the absence of social methods for keeping employees in the workplace, a high percentage of part-time jobs, the average age is 45 years; the presence of a corporate culture, a high level of qualification, the personal development of specialists with a secondary medical education, a variety of specialties within one organization.
Influence of motivational sphere on professional self-determination of medical college students
Authors:   Institute of Nursing Education, Samara State Medical University, Ministry of Healthcare of Russia,Samara, Berezkina Elena Dmitrievna , Karaseva Larisa Arkadyevna ,   Institute of Nursing Education, Head of the Department of Nursing, FSBEI of HE «Samara State Medical University» of the Ministry of Healthcare of the Russian Federation, Samara
Published: March 2022

The aim of the study is to study the influence of the motivational sphere on the professional self-determination of medical college students. Results. A theoretical analysis of scientific psychological literature was carried out, the concepts of «professional self-determination», «professional self-determination of students», «motivation of professional self-determination» were defined; the features of professional self-determination of students of secondary professional institutions were revealed; the influence of the motivational sphere of students on their professional self-determination was studied; a set of diagnostic methods was selected in order to identify the influence of the motivational sphere of students on their professional self-determination; a quantitative and qualitative analysis of the results of the empirical study was carried out. Conclusion. The study of the problem of the influence of the motivational sphere on the professional self-determination of students of secondary vocational educational institutions is an urgent problem at the present stage of development of psychological science. The educational and professional activity of students becomes successful if they have a high level of motivation for this type of activity.
A NEW DIGITAL MARKETING AREA FOR E-COMMERCE BUSINESS
Authors:   Departemen Sistem Informasi, Universitas Komputer Indonesia, Indonesia, Rosiyana Reza Nur , Agustin Melyana ,   Departemen Sistem Informasi, Universitas Komputer Indonesia, Indonesia, Iskandar Ivan Kalka ,   Departemen Sistem Informasi, Universitas Komputer Indonesia, Indonesia, Luckyardi Senny ,   Departemen Manajemen, Universitas Komputer Indonesia, Indonesia
Published: March 2022

Digital marketing is a familiar thing in the business world. One of them is a Tiktok Shop. Tiktok Shop is a new feature in Tiktok application, officially launched in April 2020. Tiktok shop has become very popular among e-commerce businesses and customers who often shop online, because this application provides an attractive and easy interface for product marketing and purchasing products. The background of this research is because tiktok shop get viral so fast as a new e-commerce media and can even run in parallel other e-commerce. Therefore, this research purposes for knowing why this e-commerce can quickly viral and be used by many people. Furthermore, it can compete with other e-commerce and become the choice of business people and customers in conducting business processes. This research method is based on observations and interviews with various parties, two as business people and customers. The results of this study are in the form of exposure based on the research objectives presented, which enables us to have concrete evidence that this tiktok shop has influence and is worthy of being used as a new e-commerce along with other e-commerce in conducting business processes. Discuss research to get answers about the influence of Tiktok Shop on marketing. which resulted in the conclusion that Tiktok Shop could be a new alternative tool for business people in carrying out their business processes. The benefit of this research is to see how far the development of tiktok shops among the public and business people.