bluuebunny/crossref_metadata_2025 huggingface dataset:
Monitoring Waterborne Pathogens in Surface and Drinking Waters. Are Water Treatment Plants (WTPs) Simultaneously Efficient in the Elimination of Enteric Viruses and Fecal Indicator Bacteria (FIB)?
Authors: Salvador Daniel , Caeiro Maria Filomena , Serejo Fátima , Nogueira Paulo , Carneiro Rui Neves , Neto Célia
Published: October 2020

Monitoring the quality of water is a requisite to prevent outbreaks related to waterborne diseases, predominantly caused by pathogens like enteric viruses, usually transmitted via the fecal-oral route. This study aimed to survey a group of enteric viruses (Enterovirus, Norovirus genogroups I and II, and hepatitis A virus) in two surface water sources of drinking water, also intending to evaluate the extent of their elimination in the two water treatment plants (WTPs) involved in drinking water production. Correlations between these viruses and fecal indicator bacteria (FIB) were also evaluated. Positive samples for viral RNA were recurrently found by reverse transcription quantitative PCR (RT-qPCR) and quantified, in genomic copies per liter (gc/L) of sampled water. Viral RNAs were detected in 14 out of 27 samples of surface water, and 21 out of 36 samples of drinking water, NoV II having been the most frequently detected in both (0–78.6 gc/L and 0–12.5 gc/L, respectively). Both WTPs showed variable efficacies in the elimination of viral RNA. Only one correlation was found with FIB, between NoV II and intestinal enterococci. These results recommend the monitoring of enteric viruses over time and their inclusion in the mandatory analysis of water quality.
Analysis and Control of the Physicochemical Quality of Groundwater in the Chari Baguirmi Region in Chad
Authors: Beyaitan Bantin Allaramadji , Wang Hongping , Jun Xia
Published: October 2020

Water resources are threatened nowadays by pollution that comes from domestic, industrial and agricultural discharges without prior treatment. This pollution causes the degradation of water quality. Surface pollutants can seep through the soil into water tables. The objective of our work is to assess and control the physicochemical quality of the Chari Baguirmi groundwater, to protect human health. The quality of 83 boreholes was assessed, while performing analysis for 12 physicochemical parameters at the National Water Laboratory and at the Center for Quality Control of Foodstuffs in Chad. These parameters are pH, EC, Ca2+, Mg2+, Na+, K+, Cl−, SO42−, NH4+ and NO3−, Fe2+ and HCO3−. The results obtained were also compared with WHO standards. The geochemical statistical approach has made it possible to characterize hydro geochemical properties and to understand the major processes of mineralization of groundwater resources in the Chari Baguirmi region in Chad. Some of its waters are acidic and weakly mineralized, rich in Fe2+ and NH4+. The origin of the mineralization is due to the alteration of the host rocks and to the hydrolysis of silicate and ferromagnesian minerals, as well as anthropogenic pollution. The ammonium concentrations in N’Djamena boreholes are higher than WHO standards, indicating the presence of pollution which may come from organic waste. These results constitute a preliminary step in understanding hydro geochemical functioning and a basis for monitoring the physicochemical quality of water in the study area.
Coastal Dynamic and Evolution: Case Studies from Different Sites around the World
Authors: Rizzo Angela , Anfuso Giorgio
Published: October 2020

In recent decades, coastal areas have experienced a progressive increase in erosion and flooding processes as a consequence of the combined effect of natural factors and strong human pressures. These processes are particularly evident on low-lying areas and are expected to be exacerbated by the ongoing climate change, which will impact the littorals both in the short term, by affecting the duration and frequency of storms, and in the long term, by inducing variation in the sea-level position. In this context, this Special Issue is devoted to collecting geomorphological studies on coastal dynamic and evolution by means of multidisciplinary research methodologies and investigations, which represent a very useful set of information for supporting the integrated management of coastal zone. The volume includes 14 papers addressing three main topics (i) shoreline characterization, dynamic and evaluation; (ii) coastal hazard evaluation and impact assessment of marine events; and (iii) relevance of sediment collection and analysis for beach nourishment. Case studies from Russia, Italy, California (USA), Morocco, Spain, Indonesia, Ireland and Colombia are shown in the Special Issue, giving to the reader a wide overview of coastal settings and methodological approaches.
A Medium-Term Study of Molise Coast Evolution Based on the One-Line Equation and “Equivalent Wave” Concept
Authors: Buccino Mariano , Di Paola Gianluigi , Ciccaglione Margherita C. , Del Giudice Giuseppe , Rosskopf Carmen M.
Published: October 2020

The Molise region (southern Italy) fronts the Adriatic Sea for nearly 36 km and has been suffering from erosion since the mid-20th century. In this article, an in-depth analysis has been conducted in the time-frame 2004–2016, with the purpose of discussing the most recent shoreline evolution trends and individuating the climate forcings that best correlate with them. The results of the study show that an intense erosion process took place between 2011 and 2016, both at the northern and southern parts of the coast. This shoreline retreat is at a large extent a downdrift effect of hard protection systems. Both the direct observation of the coast and numerical simulations, performed with the software GENESIS, indicate that the shoreline response is significantly influenced by wave attacks from approximately 10° N; however, the bimodality that characterizes the Molise coast wave climate may have played an important role in the beach dynamics, especially where structural systems alternate to unprotected shore segments.
Detection of Cover Collapse Doline and Other Epikarst Features by Multiple Geophysical Techniques, Case Study of Tarimba Cave, Brazil
Authors: Hussain Yawar , Uagoda Rogerio , Borges Welitom , Prado Renato , Hamza Omar , Cárdenas-Soto Martín , Havenith Hans-Balder , Dou Jie
Published: October 2020

Reliable characterization of the karst system is essential for risk assessment where many associated hazards (e.g., cover-collapse dolines and groundwater pollution) can affect natural and built environments, threatening public safety. The use of multiple geophysical approaches may offer an improved way to investigate such cover-collapse sinkholes and aid in geohazard risk assessments. In this paper, covered karst, which has two types of shallow caves (vadose and fluvial) located in Tarimba (Goias, Brazil), was investigated using various geophysical methods to evaluate their efficiency in the delineation of the geometry of sediments filled sinkhole. The methods used for the investigation were Electrical Resistivity Tomography (ERT), Seismic Refraction Survey (SRS), Seismic Refraction Tomography (SRT) and the Very Low Frequency Electromagnetic (VLF-EM) method. The study developed several (2D) sections of the measured physical properties, including P-wave velocity and electrical resistivity, as well as the induced current (because of local bodies). For the analysis and processing of the data obtained from these methods, the following approaches were adopted: ERT inversion using a least-square scheme, Karous-Hjelt filter for VLF-EM data and time-distance curves and Vp cross-sections for the SRS. The refraction data analysis showed three-layered stratigraphy topsoil, claystone and carbonate bedrock, respectively. The findings obtained from ERT (three-layered stratigraphy and sediment-filled doline), as well as VLF-EM (fractured or filled caves as a positive anomaly), were found to be consistent with the actual field conditions. However, the SRS and SRT methods did not show the collapsed material and reached the limited the depth because of shorter profile lengths. The study provides a reasonable basis for the development of an integrated geophysical approach for site characterization of karst systems, particularly the perched tank and collapse doline.
Study of Scour Characteristics Downstream of Partially-Blocked Circular Culverts
Authors: Taha Nesreen , El-Feky Maged M. , El-Saiad Atef A. , Zelenakova Martina , Vranay Frantisek , Fathy Ismail
Published: October 2020

Debris accumulations upstream and through crossing hydraulic structures such as culverts cause the upstream water level and the downstream scour depth to increase, which can lead to structure failure. This experimental study aimed to investigate the effects of various inlet blockage ratios on culvert efficiency and scour hole depth. In a non-blocked case, various submergence ratios (S = 1.06, 1.33, 1.60, and 1.90) were tested with different discharge rates. In a blocked case, the effects of inlet blockage with various blockage ratios (Ar = 10%, 20%, and 30%) were seen as sediment blockage on the pipe bed or floating debris upstream of the culvert. The results show that as the submergence ratio increases, the maximum scour depth decreases at the same discharge rate, and the relative energy loss also decreases in the non-blocked case. In the sediment blockage (Ar d) case, the relative maximum depth increases with increasing densimetric Froude number and with an increasing blockage ratio. An empirical equation was developed to predict the relative scour depth under the present study conditions.
Engineered Biochar Production and Its Potential Benefits in a Closed-Loop Water-Reuse Agriculture System
Authors: Li Simeng , Chan Celeste Y. , Sharbatmaleki Mohamadali , Trejo Helen , Delagah Saied
Published: October 2020

Biochar’s potential to remove various contaminants from aqueous solutions has been widely discussed. The rapid development of engineered biochar produced using different feedstock materials via various methods for wastewater treatment in recent years urges an up-to-date review on this topic. This article centers on summarizing state-of-the-art methods for engineered biochar production and discussing the multidimensional benefits of applying biochar for water reuse and soil amendment in a closed-loop agriculture system. Based on numerous recent articles (<5 years) published in journals indexed in the Web of Science, engineered biochar’s production methods, modification techniques, physicochemical properties, and performance in removing inorganic, organic, and emerging contaminants from wastewater are reviewed in this study. It is concluded that biochar-based technologies have great potential to be used for treating both point-source and diffuse-source wastewater in agricultural systems, thus decreasing water demand while improving crop yields. As biochar can be produced using crop residues and other biomass wastes, its on-farm production and subsequent applications in a closed-loop agriculture system will not only eliminate expensive transportation costs, but also create a circular flow of materials and energy that promotes additional environmental and economic benefits.
Analytical and Numerical Methods for a Preliminary Assessment of the Remediation Time of Pump and Treat Systems
Authors: Antelmi Matteo , Renoldi Francesca , Alberti Luca
Published: October 2020

Several remediation technologies are currently used to address groundwater pollution. “Pump and treat” (P&T) is probably one of the most widely applied, being a process where contaminated groundwater is extracted from the subsurface by pumping and then treated before it is discharged or reinjected into the aquifer. Despite being a very adaptable technology, groundwater remediation is often achieved in long and unsustainable times because of limitations due to the hydrogeological setting and contaminant properties. Therefore, the cost–benefit analysis over time results in an inefficient system and a preliminary evaluation of the clean-up time is crucial. The aim of the paper is to compare, in an integrated manner, the application of some models to estimate the time to compliance of a P&T system in relation to the specific hydrogeological condition. Analytical solutions are analyzed and applied to an industrial site and to a synthetic case. For both cases, batch flushing and the advection-dispersion-retardation (ADR) model underestimate remediation times comparing the results to real or simulated monitoring data, whereas the Square Root model provided more reliable remediation times. Finally, for the synthetic case, the reliability of analytical approaches and the effects of matrix diffusion are tested on the basis of a numerical groundwater transport model specifically implemented, which confirm the results of the analytical methods and the strong influence of the matrix diffusion on the results.
The Structure of Riparian Vegetation in Agricultural Landscapes Influences Spider Communities and Aquatic-Terrestrial Linkages
Authors: Ramberg Ellinor , Burdon Francis J. , Sargac Jasmina , Kupilas Benjamin , Rîşnoveanu Geta , Lau Danny C. P. , Johnson Richard K. , McKie Brendan G.
Published: October 2020

Riparian habitats are important ecotones connecting aquatic and terrestrial ecosystems, but are often highly degraded by human activities. Riparian buffers might help support impacted riparian communities, and improve trophic connectivity. We sampled spider communities from riparian habitats in an agricultural catchment, and analyzed their polyunsaturated fatty acid (PUFA) content to quantify trophic connectivity. Specific PUFAs are exclusively produced by stream algae, and thus are used to track uptake of aquatic resources by terrestrial consumers. Riparian spiders were collected from 10 site pairs situated along agricultural streams, and from five forest sites (25 sites total). Each agricultural site pair comprised an unshaded site with predominantly herbaceous vegetation cover, and a second with a woody riparian buffer. Spider communities differed between site types, with web-building spiders dominating woody buffered sites and free-living spiders associated with more open habitats. PUFA concentrations were greatest overall in free-living spiders, but there was also evidence for increased PUFA uptake by some spider groups when a woody riparian buffer was present. Our results reveal the different roles of open and wooded riparian habitats in supporting terrestrial consumers and aquatic-terrestrial connectivity, and highlight the value of incorporating patches of woody vegetation within riparian networks in highly modified landscapes.
Pipe Fault Prediction for Water Transmission Mains
Authors: Gorenstein Ariel , Kalech Meir , Hanusch Daniela Fuchs , Hassid Sharon
Published: October 2020

Every network of supply waterlines experiences thousands of yearly bursts, breaks, leakages, and other failures. These failures waste a great amount of resources, as not only the waterlines need to be repaired, but also water is wasted and the distribution service is interrupted. For that reason, many water facilities employ proactive maintenance strategies in their networks, where they replace likely-to-fail pipes in advance to prevent the failures. In this paper, we aim to establish a reliable prediction model that can accurately predict faults in waterlines prior to their occurrence. We propose a specific segmentation method for long transmission mains, as well as three data-driven models and one rule-based prediction model. We evaluate a real world waterline network used in Israel, operated by Mekorot company, using three common metrics. The results show that the data-driven algorithms outperform the rule-based model by at least 5% in each of the metrics. Additionally, their prediction becomes more accurate as they are trained with more data, but enhancing these data with geographically related features does not improve the accuracy further.
Influence of Climate and Land Use Change on the Groundwater System of the Veluwe, The Netherlands: A Historical and Future Perspective
Authors: Van Huijgevoort Marjolein H. J. , Voortman Bernard R. , Rijpkema Sjoerd , Nijhuis Kelly H. S. , Witte Jan-Philip M.
Published: October 2020

Changes in land use and climate have a large influence on groundwater recharge and levels. In The Netherlands, precipitation shifts from summer to winter are expected, combined with an increase in summer temperature leading to higher evaporation. These changes in climate could threaten the fresh water supply and increase the importance of large groundwater reservoirs. Sustainable management of these groundwater reservoirs, therefore, is crucial. Changes in land use could help mitigate the effects of climate change by decreasing the evaporation. In this study, we investigate the effect of changes in climate and land use on a large groundwater reservoir in The Netherlands, the Veluwe, for a historical period (1850–2016) and in the future (2036–2065). During the historical period, evaporation increased due to conversions from heather and drift sand to pine forest across the Veluwe. This change in land use had a larger effect on the groundwater recharge than change in climate over the historical period. In the future, an increase in winter precipitation will lead to higher groundwater levels in the elevated parts of the region. Surrounding areas are more vulnerable to an increase in dry periods in the summer. Groundwater reservoirs provide an opportunity to store water during wetter periods, which could alleviate drought impacts in surrounding regions during dry periods. Land use change, such as conversion from pine forest to other land use types, is a possible measure to increase water availability.
The Use of Biochar and Pyrolysed Materials to Improve Water Quality through Microcystin Sorption Separation
Authors: Frišták Vladimír , Laughinghouse H. Dail , Bell Stephen M.
Published: October 2020

Harmful algal blooms have increased globally with warming of aquatic environments and increased eutrophication. Proliferation of cyanobacteria (blue-green algae) and the subsequent flux of toxic extracellular microcystins present threats to public and ecosystem health and challenges for remediation and management. Although methods exist, there is currently a need for more environmentally friendly and economically and technologically feasible sorbents. Biochar has been proposed in this regard because of its high porosity, chemical stability, and notable sorption efficiency for removing of cyanotoxins. In light of worsening cyanobacterial blooms and recent research advances, this review provides a timely assessment of microcystin removal strategies focusing on the most pertinent chemical and physical sorbent properties responsible for effective removal of various pollutants from wastewater, liquid wastes, and aqueous solutions. The pyrolysis process is then evaluated for the first time as a method for sorbent production for microcystin removal, considering the suitability and sorption efficiencies of pyrolysed materials and biochar. Inefficiencies and high costs of conventional methods can be avoided through the use of pyrolysis. The significant potential of biochar for microcystin removal is determined by feedstock type, pyrolysis conditions, and the physiochemical properties produced. This review informs future research and development of pyrolysed materials for the treatment of microcystin contaminated aquatic environments.
A Complex Method for Estimation of Multiple Abiotic Hazards in Forest Ecosystems
Authors: Středová Hana , Fukalová Petra , Chuchma Filip , Středa Tomáš
Published: October 2020

Forest ecosystems are faced with a variety of threats, including increasingly prolonged droughts and other abiotic stresses such as extreme high temperatures, very strong wind, invasive insect outbreaks, and the rapid spread of pathogens. The aim of the study was to define crucial abiotic stressors affecting Central Europe forest ecosystems and, with regard to their possible simultaneous effect, develop a universal method of multi-hazard evaluation. The method was then applied to the particular area of interest represented by part of the Czech Republic with forest land cover (12–19 ° E, 48–51 ° N). Based on National Threat Analysis, the most significant threats of natural origin with a close relationship to forest stability were identified as drought, high temperature, and wind gusts. Using suitable indicators, a level of their risk based on occurrence and consequences was estimated. The resulting combined level of risk, divided into five categories, was then spatially expressed on a grid map. The novelty of our paper lies in: (i) all relevant climatic data were combined and evaluated simultaneously with respect to the different level of risk, (ii) the developed methodological road map enables an application of the method for various conditions, and (iii) multiple hazards were estimated for the case study area.
Study of the Water Quality Index and Polycyclic Aromatic Hydrocarbon for a River Receiving Treated Landfill Leachate
Authors: Tan Pei Jian Brenda , Ul Mustafa Muhammad , Hasnain Isa Mohamed , Yaqub Asim , Ho Yeek Chia
Published: October 2020

Rising solid waste production has caused high levels of environmental pollution. Population growth, economic patterns, and lifestyle patterns are major factors that have led to the alarming rate of solid waste production. Generally, solid wastes such as paper, wood, and plastic are disposed into landfills due to its low operation and maintenance costs. However, leachate discharged from landfills could be a problem in surfaces and groundwater if not adequately treated. This study investigated the patterns of the water quality index (WQI) and polycyclic aromatic hydrocarbons (PAH) along Johan River in Perak, Malaysia, which received treated leachate from a nearby landfill. An artificial neural network (ANN) was also applied to predict WQI and PAH concentration of the river. Seven sampling stations were chosen along the river. The stations represented the upstream of leachate discharge, point of leachate discharge, and five locations downstream of the landfill. Sampling was conducted for one year starting July 2018. Physicochemical parameters, namely pH, biological oxygen demand, chemical oxygen demand, ammoniacal nitrogen, total suspended solids, and dissolved oxygen, were used to compute the water quality index (WQI). PAH concentrations were determined by liquid–liquid extraction of water samples followed by an analysis using gas chromatography. Results showed that WQI of Johan River was under Class III where intensive treatment was required to make it suitable for drinking purposes. The highest recorded PAH concentrations were fluoranthene (333.4 ppb) in the dry season and benzo(a) pyrene (93.5 ppb) in the wet season. A correlation coefficient (Rp) for a model prediction based on WQI-ANN and TEC-ANN (toxicity equivalent concentration) in the wet and dry seasons was 0.9915, 0.9431, 0.9999, and 0.9999, respectively. ANN results showed good model performance with Rp ≈ 0.9. This study suggested that ANN is a useful tool for water quality studies.
Insights on the Water–Energy–Food Nexus
Authors: Kanakoudis Vasilis , Tsitsifli Stavroula
Published: October 2020

This Special Issue addresses topics on the water–energy–food (WEF) nexus along with other water-related topics, such as water resources, irrigation and drinking water supply systems, hydraulics and pollution. Several threats jeopardize freshwater availability and quality, energy and food availability. Integrated management approaches are absolutely necessary for pursuing sustainability. This Special Issue addresses various subjects and includes 29 peer-reviewed papers that have been grouped into the following categories: the WEF nexus, water resources and irrigation systems, drinking water supply systems, hydraulics and pollution. Some of them were selected from the Third Efficient Water Systems (EWaS) International Conference, entitled “Insights on the Water–Energy–Food Nexus,” after a thorough content update. Summaries of the papers are briefly presented in this Editorial.
Comprehensive Assessment of Water Sensitive Urban Design Practices based on Multi-criteria Decision Analysis via a Case Study of the University of Melbourne, Australia
Authors: Xiong Hanxiang , Sun Yafei , Ren Xingwei
Published: October 2020

Water sensitive urban design (WSUD), as a typical green stormwater infrastructure (GSI), contains various facilities to decrease the urbanization impacts and enhance the values of amenity, ecosystem, and livability in Australia. Although WSUD has developed over 30 years, existing studies for WSUD performances have sometimes ignored its economic and social benefits, and there is still a lack of an integrated framework to optimize the GSI combinations based on various criteria in a site. This paper aims to utilize “score-rank-select” strategy to comprehensively assess WSUD combination scenarios from functional, economic, social, and environmental aspects, by taking the University of Melbourne (Parkville campus) as a case study. In detail, multi-criteria decision analysis (MCDA) was used for weight determination and scenario comparison. The results showed that scenario 4 with 52% green WSUD facilities had the highest assessment score (0.771) among the five scenarios, while the final score (0.758) of scenario 5 was lower than scenario 4 although its green facility proportion reached 69%. The trade-off relation between the proportion of grey and green WSUD facilities was further demonstrated. Additionally, this paper strongly recommends that the MCDA-based comprehensive assessment framework described here can be generally promoted for the water sector to solve the decision-making problems. The use of such a framework can further promote sustainable development by helping water managers to make informed and inclusive decisions involving a variety of factors.
Decadal Spatiotemporal Halocline Analysis by ISAS15 Due to Influx of Major Rivers in Oceans and Discrepancies Illustrated Near the Bay of Bengal
Authors: Iqbal Kashif , Piao Shengchun , Zhang Minghui
Published: October 2020

The discharge from rivers is one of the major factors of regional salinity perturbations in addition to precipitation, evaporation, and circulation of the ocean, whereas simulations regarding the marine environment are dominantly affected by ocean salinity. Moreover, perturbations in the timing and quantity of freshwater cause salinity fluctuations, which in turn, affect the communities of both plant and fauna. In this regard, the study ingeniously employs In Situ Analysis System-15 (ISAS15) data, which is freely available online, to ascertain the salinities in proximity of the major rivers around the globe. Such computations are multilayered, i.e., for 1, 3, 5, and 10 m, and conducted along major freshwater influxes, i.e., the Amazon River, Bay of Bengal (BoB), and Yangtze River, on decadal scales, i.e., in 2004 and in 2014. Depending upon the location and availability of ISAS-15 data, the area in proximity of the Amazon is analyzed horizontally, vertically, and obliquely, whereas the areas in proximity of the BoB and Yangtze estuary are analyzed vertically and obliquely. Similarly, the study analyzed the freshwater influx at the aforementioned locations both for the maxima and minima, i.e., during the particular months that observed the maximum and minimum influx into the ocean from the above-mentioned freshwater sources in 2004, as well as in 2014. The detailed analysis proved the outcomes to be conforming with the documented literary data along the Amazon and Yangtze estuaries. However, the computed analysis illustrated the anomalous values in proximity of the BoB. The study proceeds to discuss an ingenious approach of computing, as well as extrapolating, the salinities, temperatures, and sound speed profiles (SSPs) by employing in situ deep Argo data in order to counter such anomalies, as well as conjoin it with ISAS data, to investigate such regions with broader spatiotemporal capabilities for the future course of action. For this particular study, this method is employed on certain Argo buoys in order to prove the efficacy of the aforementioned novel approach.
Effect of Soluble Salt Loss via Spring Water on Irrigation-Induced Landslide Deformation
Authors: Zhang Zonglin , Zeng Runqiang , Meng Xingmin , Zhang Yi , Zhao Shufen , Ma Jianhua , Yao Yunqi
Published: October 2020

Landslide exposes the previously blocked groundwater discharge. High concentrations of soluble salt form salt sinters that can be observed near discharge passages. Based on existing laboratory investigation results of soil leaching and shearing reported in the literature, the effect of the soluble salt loss via spring water on irrigation-induced landslide deformation was studied under large-scale conditions. During our field investigation of landslides in the Heitai terrace of the Yellow River’s upper reaches in Gansu Province, China, 35 spring outlets were found, and the Heitai terrace was divided into five subareas, based on the difference in spring flow. Deformation data for the terrace were obtained by small baseline subset technology (SBAS-InSAR). These data were analyzed in combination with the amount of soluble salt loss, to explore the correlation between the deformation of the landslide and the soluble salt loss in the loess irrigation area. The results showed that the cumulative deformation and the loss of soluble salt were increasing continuously in the terrace. Although the increasing intensity of each subarea was different, the changing intensity of the two during the corresponding monitoring period was highly consistent. The statistical analysis revealed a strong positive correlation between the accumulated loss of soluble salt via spring water and the accumulated displacement of the terrace edge (p < 0.01). After the slope k between the two was tested by the Grubbs test and t-test, the k was no abnormality (α = 0.05) and difference (Sig > 0.05), further providing the basis for confirming the existence of this positive correlation. When the loss of soluble salt in rock and soil increased gradually, the accumulated deformation of the terrace edge also increased continuously. The findings of this study are of great significance for understanding the formation mechanism of landslides and the identifying landslide revival in irrigation areas of the Loess Plateau.
Impact of Climate Change on the Frequency of Dynamic Breakup Events and on the Risk of Ice-Jam Floods in Quebec, Canada
Authors: Turcotte Benoit , Morse Brian , Pelchat Gabriel
Published: October 2020

In cold regions, every year, river-ice jams generate sudden, surprising, intense flooding that challenges the capacity of public security services. This type of flood is commonly unpredictable and often appears chaotic because its occurrence depends on multiple, interacting weather, hydrological, ice and morphological parameters. This paper presents the findings of a research project assessing how climate change impacts dynamic river-ice breakup and associated floods along seven rivers of the province of Quebec, Canada. A combination of empirical river-ice breakup models, state-of-the-art hydrological simulations and standardized climate projections was used to estimate the historical (1972–2000) and future (2042–2070) frequencies of dynamic breakup events. Ice jam flood damage reimbursement data were used to predict changes to financial risk associated with dynamic breakup events. Results show that, overall, ice-jam floods will generate more damage in the future, which justifies watershed-based flood adaptation plans that take into account cold regions hydrological processes. The success of the methodology also sets the table for a comparable project that would include more rivers from different regions of Northeastern America.
Effectiveness of Nature-Based Solutions in Mitigating Flood Hazard in a Mediterranean Peri-Urban Catchment
Authors: S.Ferreira Carla , Mourato Sandra , Kasanin-Grubin Milica , J.D. Ferreira António , Destouni Georgia , Kalantari Zahra
Published: October 2020

Urbanization alters natural hydrological processes and enhances runoff, which affects flood hazard. Interest in nature-based solutions (NBS) for sustainable mitigation and adaptation to urban floods is growing, but the magnitudes of NBS effects are still poorly investigated. This study explores the potential of NBS for flood hazard mitigation in a small peri-urban catchment in central Portugal, prone to flash floods driven by urbanization and short but intense rainfall events typical of the Mediterranean region. Flood extent and flood depth are assessed by manually coupling the hydrologic HEC-HMS and hydraulic HEC-RAS models. The coupled model was run for single rainfall events with recurrence periods of 10–, 20–, 50–, and 100–years, considering four simulation scenarios: current conditions (without NBS), and with an upslope NBS, a downslope NBS, and a combination of both. The model-simulation approach provides good estimates of flood magnitude (NSE = 0.91, RMSE = 0.08, MAE = 0.07, R2 = 0.93), and shows that diverting streamflow into abandoned fields has positive impacts in mitigating downslope flood hazard. The implementation of an upslope NBS can decrease the water depth at the catchment outlet by 0.02 m, whereas a downslope NBS can reduce it from 0.10 m to 0.23 m for increasing return periods. Combined upslope and downslope NBS have a marginal additional impact in reducing water depth, ranging from 0.11 m to 0.24 m for 10– and 100–year floods. Decreases in water depth provided by NBS are useful in flood mitigation and adaptation within the peri-urban catchment. A network of NBS, rather than small isolated strategies, needs to be created for efficient flood-risk management at a larger scale.
Ecologically Non-Invasive Decontamination of Natura 2000 Locality from Old Deposits of Hexavalent Chromium and Bivalent Nickel by Modular Electrocoagulation Combined with Ca(OH)2 Addition
Authors: Krystynik Pavel , Masin Pavel , Krusinova Zuzana , Kluson Petr
Published: October 2020

A modular electrocoagulation unit, supported by Ca(OH)2 addition to treated water, was operated in the vicinity of a Natura 2000 site for the removal of Cr6+ or Ni2+ from contaminated groundwater. The process was performed at a constant flow rate of 350 L/h. Day 0 concentrations of Cr6+ and Ni2+ started at 91.6 mg/L for Ni2+ and 43 mg/L for Cr and during testing, were decreased by 15%–25%. Residual concentrations of Crtot. and Ni2+ below the required limits of 0.5 mg/L for Crtot. and 0.8 mg/L for Ni2+ can be achieved with the electrocoagulation unit and total removal efficiencies often exceeded 98%. The overall economic assessment showed its feasible application for removal of Cr6+ and Ni2+ on sites with requirements of high environmental protection standards. The polluted area was about 150 × 150 m (22,500 m2), and it contained approximately 78,750 m3 of water contaminated with Cr6+ and Ni2+ (over 41 and 91 mg/L, respectively). The modular arrangement might allow a scaling up. The process’ output could be thus increased according to the number of EC modules in operation.
Hydraulic Transient Analysis of Sewer Pipe Systems Using a Non-Oscillatory Two-Component Pressure Approach
Authors: Khani David , Lim Yeo Howe , Malekpour Ahmad
Published: October 2020

On the basis of the two-component pressure approach, we developed a numerical model to capture mixed transient flows in close conduit systems. To achieve this goal, an innovative Godunov finite-volume numerical scheme is proposed to suppress the spurious numerical oscillations occurring during rapid pipe pressurization. To dissipate the spurious numerical oscillations, we admit artificial numerical viscosity to the numerical scheme through applying a proposed Harten, Lax, and van Leer (HLL) Riemann solver for calculating the numerical fluxes at the computational cell interfaces. The proposed solver controls the magnitude of the numerical viscosity through adjusting the left and right wave velocities. A wave velocity calculator is proposed to optimally distribute the numerical viscosity over several computational cells around the computational cell in which the pressurization front is located. The proposed solver admits significant artificial numerical viscosity when the pipe pressurization is imminent and automatically reduces it in other places; in this way the numerical diffusion and data smearing is minimized. The validity of the proposed model is justified by the aid of several test cases in which the numerical results are compared with both experimental data and the results obtained from analytical methods. The results reveal that the proposed model succeeds in completely removing the spurious numerical oscillations, even when the pipe acoustic speed is over 1000 m/s. The numerical results also show that the model can successfully capture occurrence of negative pressures during the course of transient flow.
Removal of Diclofenac in Effluent of Sewage Treatment Plant by Photocatalytic Oxidation
Authors: Ma Nan , Zhang Nannan , Gao Ling , Yuan Rongfang , Chen Huilun , Hou Xuerui , Hou Jiawei , Wang Fei , Zhou Beihai
Published: October 2020

Diclofenac (DCF) has been widely found in sewage treatment plants and environmental water bodies, and has attracted worldwide attention. In this paper, the photocatalytic degradation of DCF was investigated using a laboratory-scale simulated solar experimental device. This study focused on exploring the effects of the actual secondary effluent from sewage treatment plants (SE-A and SE-B) on the photocatalytic degradation of DCF and the changes of dissolved organic matter (DOM) during the photocatalytic degradation process. The results showed when SE-A and SE-B were used as the background water of the DCF solution, they displayed a significant inhibitory effect on the degradation of DCF, and the values of k were 0.039 and 0.0113 min−1, respectively. Among them, DOM played a major inhibitory role in photocatalytic degradation of DCF in sewage. In the photocatalytic process, the biological toxicity of the DCF solution was the least after 30 min of reaction, and then gradually increased. Furthermore, the organic matters in the sewage were greatly degraded after the photocatalytic reaction, including 254 and 365 nm ultraviolet (UV254, UV365) and chemical oxygen demand (COD). Moreover, titanium dioxide (TiO2) first catalyzed the degradation of macromolecular organic matters, and then degraded the small molecular organic matters.
In Situ Rates of Carbon and Nitrogen Uptake by Phytoplankton and the Contribution of Picophytoplankton in Kongsfjorden, Svalbard
Authors: Kim Bo Kyung , Joo Hyoung Min , Jung Jinyoung , Lee Boyeon , Ha Sun-Yong
Published: October 2020

Rapid climate warming and the associated melting of glaciers in high-latitude open fjord systems can have a significant impact on biogeochemical cycles. In this study, the uptake rates of carbon and nitrogen (nitrate and ammonium) of total phytoplankton and picophytoplankton (<2 μm) were measured in Kongsfjorden in early May 2017 using the dual stable isotope technique. The daily uptake rates of total carbon and nitrogen ranged from 0.3 to 1.1 g C m−2 day−1, with a mean of 0.7 ± 0.3 g C m−2 day−1, and 0.13 to 0.17 g N m−2 day−1, with a mean of 0.16 ± 0.02 g N m−2 day−1. Microphytoplankton (20–200 μm) accounted for 68.1% of the total chlorophyll a (chl-a) concentration, while picophytoplankton (<2 μm) accounted for 19.6% of the total chl-a, with a high contribution to the carbon uptake rate (42.9%) due to its higher particulate organic carbon-to-chl-a ratio. The contributions of picophytoplankton to the total nitrogen uptake rates were 47.1 ± 10.6% for nitrate and 74.0 ± 16.7% for ammonium. Our results indicated that picophytoplankton preferred regenerated nitrogen, such as ammonium, for growth and pointed to the importance of the role played by picophytoplankton in the local carbon uptake rate during the early springtime in 2017. Although the phytoplankton community, in terms of biovolume, in all samples was dominated by diatoms and Phaeocystis sp., a higher proportion of nano- and picophytoplankton chl-a (mean ± SD = 71.3 ± 16.4%) was observed in the relatively cold and turbid surface water in the inner fjord. Phytoplankton production (carbon uptake) decreased towards the inner fjord, while nitrogen uptake increased. The contrast in carbon and nitrogen uptake is likely caused by the gradient in glacial meltwater which affects both the light regime and nutrient availability. Therefore, global warming-enhanced glacier melting might support lower primary production (carbon fixation) with higher degrees of regeneration processes in fjord systems.
Collaborative Action and Social Organization in Remote Rural Regions: Autonomous Irrigation Arrangements in the Pamirs of Tajikistan
Authors: Dörre Andrei
Published: October 2020

This paper proposes a bottom–up “nexus medium” perspective to examine and understand social organization and how socio-ecological challenges in remote rural regions are dealt with in communities that receive only limited external support. While “nexus mediums” constitute substances, matter, or objects that combine manifold vital meanings and can be seen as socially constructed and materialized arenas of social interaction, autonomous resource management is seen as a means of local social organization. Taking water as the nexus medium of choice allows us to generate locally informed insights about the role of this scarce resource for the everyday life and social organization of communities inhabiting arid rural areas. This reasoning will be exemplified by three local case studies conducted during empirical research in the Pamirs of Tajikistan utilizing a mix of qualitative methods. The findings reveal how many fundamental everyday-life-related aspects and activities of the studied communities are related to water, and how these communities are organized around common water use and management arrangements that are based on joint decision-making, shared benefits and responsibilities, and collaborative action. The “nexus medium” concept appears to be an appropriate approach for research that seeks to understand from a local perspective how communal living is organized and how socio-ecological challenges are addressed.
Plastic Film Mulch Performed Better in Improving Heat Conditions and Drip Irrigated Potato Growth in Northwest China than in Eastern China
Authors: Zhang Youliang , Feng Ren , Nie Wei , Wang Fengxin , Feng Shaoyuan
Published: October 2020

Plastic film (i.e., transparent and black films) is widely applied in mulching to improve thermal environments and plant growth in China. However, choosing suitable film for potato cultivation in different areas is still a problem. A four-year field experiment was conducted to explore the influences of plastic mulch on heat transfer (soil heat flux, G; soil temperature; and canopy net radiation, Rn) and potato growth in two typical areas of China: Experiment 1 in Northwest China (2014 and 2015) and Experiment 2 in Eastern China (2016 and 2017). Three mulch treatments were designed as follows: (1) transparent film (TF), (2) black film (BF), and (3) no film (NF). Results showed that the Rn and G differences between TF, BF, and NF varied at different areas. However, the Rn in TF was always smaller (average 12.4 W/m2 in 2014–2017) than in BF in the two study areas. The differences of soil temperature between TF, BF, and NF in Experiment 1 were greater than in Experiment 2. The average soil temperature difference between TF and NF was 1.4 °C higher in Experiment 1 than in Experiment 2. TF had 23% and 19% more jumbo tubers than BF in weight and number on average with no significant difference in 2015–2017. TF and BF significantly had greater potato yield and irrigation water use efficiency than NF on average in Experiment 1, while no significant differences were found in Experiment 2. The transparent film was more beneficial to increase soil temperature and jumbo tubers than the black film. Film mulch functioned better for improving heat conditions and drip-irrigated potato growth in Northwest China than in Eastern China.
History, Colonialism, and Archival Methods in Socio-Hydrological Scholarship: A Case Study of the Boerasirie Conservancy in British Guiana
Authors: Mullenite Joshua
Published: October 2020

In this article, I review a cross-section of research in socio-hydrology from across disciplines in order to better understand the current role of historical-archival analysis in the development of socio-hydrological scholarship. I argue that despite its widespread use in environmental history, science and technology studies, anthropology, and human geography, archival methods are currently underutilized in socio-hydrological scholarship more broadly, particularly in the development of socio-hydrological models. Drawing on archival research conducted in relation to the socio-hydrology of coastal Guyana, I demonstrate the ways in which such scholarship can be readily incorporated into model development.
PENGARUH REKRUTMEN DAN PELATIHAN TERHADAP KINERJA PEGAWAI PADA PT. ANGKASA PURA II
Authors: Sukatmajaya Ahmad , N. Catur Fery
Published: October 2020

PT. Angkasa Pura II adalah salah perusahaan yang berada dibawah kementerian perhubungan.Perusahaan ini berkedudukan di Jakarta dan mempunyai tugas utama mengatur kegiatan yangberhubungan dengan penerbangan. Penelitian ini mengambil judul “Pengaruh Rekruitmen DanPelatihanTerhadap Kinerja Pegawai Pada PT Angkasa Pura II”. Penelitian ini menggunakan dataprimer. Data penelitian diperoleh melalui penyebaran kuesioner kepada para pegawai, yangkemudian dari jawaban kuesioner tersebut diolah dan dilakukan pengujian statistik dengan alatuji regresi, korelasi, dan uji F menggunakan program SPSS versi 20. Setelah dilakukan pengujiandiperoleh persamaan regresi Y = 33,106 + 0,219 (X1)+ 0,405 (X2) dan dapat diketahui Nilai a =33,106 artinya jika tidak ada kenaikan dari variabel rekrutmen dan pelatihan maka kinerjapegawai adalah 33,106. Nilai b1 = 0,219, artinya setiap perubahan rekrutmen (X1) senilai 1 satuanakan meningkatkan kinerja pegawai sebesar 0,219. Nilai b2 = 0,405, artinya setiap perubahanpelatihan (X2) senilai 1 satuan akan meningkatkan kinerja pegawai sebesar 0,405. Dari hasilperhitungan koefisien korelasi berganda r = 0,373 artinya terdapat pengaruh korelasi yang rendahantara X1,X2 terhadap Y. Dari hasil perhitungan analisis korelasi dapat dilihat bahwa nilai R =0,373 atau 37,3% hal ini menunjukan adanya korelasi yang rendah antara seleksi dan pelatihanterhadap kinerja pegawai. Dari hasil perhitungan analisis determinasi (r2) = 0,139 artinyakontribusi rekrutmen (X1) dan pelatihan (X2) terhadap kinerja pegawai (Y) sebesar 13,9%,sedangkan sisanya sebesar 86,1% dipengaruhi oleh variabel lain yang tidak dijelaskan dalampenelitian ini. Hasil pengujian hipotesis menunjukkan, Ha diterima dan Ho ditolak karena tingkatsignifikasi 0,090 < 0,05 dan Fhitung 2,593 > Ftabel 3,29 artinya bahwa rekrutmen dan pelatihansecara bersama-sama berpengaruh signifikan terhadap kinerja pegawai.