bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhanced Functional Properties of Low-Density Polyethylene Nanocomposites Containing Hybrid Fillers of Multi-Walled Carbon Nanotubes and Nano Carbon Black
Authors: Paszkiewicz Sandra , Szymczyk Anna , Zubkiewicz Agata , Subocz Jan , Stanik Rafal , Szczepaniak Jedrzej
Published: June 2020

In this work, hybrid filler systems consisting of multi-walled carbon nanotubes (MWCNTs) and nano carbon black (nCB) were incorporated by melt mixing in low-density polyethylene (LDPE). To hybrid systems a mixture of MWCNTs and nCB a mass ratio of 1:1 and 3:1 were used. The purpose was to study if the synergistic effects can be achieved on tensile strength and electrical and thermal conductivity. The dispersion state of carbon nanofillers in the LDPE matrix has been evaluated with scanning electron microscopy. The melting and crystallization behavior of all nanocomposites was not significantly influenced by the nanofillers. It was found that the embedding of both types of carbon nanofillers into the LDPE matrix caused an increase in the value of Young’s modulus. The results of electrical and thermal conductivity were compared to LDPE nanocomposites containing only nCB or only MWCNTs presented in earlier work LDPE/MWCNTs. It was no synergistic effects of nCB in multi-walled CNTs and nCB hybrid nanocomposites regarding mechanical properties, electrical and thermal conductivity, and MWCNTs dispersion. Since LDPE/MWCNTs nanocomposites exhibit higher electrical conductivity than LDPE/MWCNTs + nCB or LDPE/nCB nanocomposites at the same nanofiller loading (wt.%), it confirms our earlier study that MWCNTs are a more efficient conductive nanofiller. The presence of MWCNTs and their concentration in hybrid nanocomposites was mainly responsible for the improvement of their thermal conductivity.
Grave Reminders: Grief and Vulnerability in the Anthropocene
Authors: Sideris Lisa H.
Published: June 2020

This essay builds upon recent work in the environmental humanities, and that of various writers and journalists, on the emerging topic of environmental grief and mourning. I consider a spectrum of responses to Anthropocene-era crises like climate change and extinction, with particular emphasis on how we are oriented toward the past and the future. These perspectives range from positions that explicitly reject grief and vulnerability, to voices urging us to embrace grief as part of an essential moral and spiritual environmental practice. At one end of the spectrum, we find articulations of what I call climate humanism, a style of response focused on defending and perpetuating human civilization in the midst of environmental crisis, but with little or no explicit concern for the broader web of living and dying beings. For climate humanists, to grieve for the past and its mistakes is to halt progressive, optimistic movement into the future. At the other end of the spectrum, we find scholars and writers who take profound grief, and sustained reflection on death and loss, as the starting point for genuine, transformative change and the possibility of hope. Drawing on this range of responses to environmental threats and losses, I endorse narratives that ground themselves in the past, in all its surprises and mistakes, as a vital resource and repository for moving hopefully and purposefully into the future. Moral, religious, and religious-like dimensions of environmental grief (or its denial) are recurring themes throughout, and many crucial insights are found in scholarship outside of religious studies.
Evaluation of Influence of the Environment on the Choice of Buildings for Residential Living
Authors: Bartoněk Dalibor , Bureš Jiří , Švábenský Otakar
Published: June 2020

In the CR (Czech Republic), there are a lot of prefabricated housing estates built in the 70s and 80s of the 20th century, which are at the end of their life cycle. The main goal of the project was to evaluate the rate of energy savings in the long term due to the revitalization of prefabricated apartment buildings, and thus provide feedback to the relevant authorities on its effectiveness. Another goal was to evaluate selected parameters of living comfort in the locality for the purposes of the real estate market with the possibility of providing them to those interested in living in the locality. A complex of methods was used, which evaluate criteria from various spheres, such as environment, spatial relationships, social aspects, etc. The authors used a combination of multi-criterial analysis methods (MCA) and spatial analysis within a Geographical Information System (GIS). Of all MCA methods, weighted linear combination (WLC) was chosen as the most suitable. In the spatial analyses, the matter of solution was, above all, the distance to the center and the transport within the given locality. The above-mentioned methods served as a model for evaluating whether a panel house in question is or is not suitable for reconstruction. The input data of the model are spatial data—national map series of the CR, environmental data (noise maps, energy demands of buildings)—and statistical data obtained from various sources (city administration of Brno, relevant organizations, and interviews with respondents). Within Inquiry Form 3, potential groups of respondents were addressed: Group A—people over fifty, group B—young families with children, group C—students under 25. The projected model was tested in Brno city in the locality of Nový Lískovec (CR). The proposed model provided information on the quality of housing in a given locality in terms of energy intensity, noise pollution, transport accessibility, and civic amenities. The output is a multi-criteria model with GIS support, which is generally applicable. The results of the model analyses led to the demonstration of the effectiveness of revitalization. The results can be used for estate offices or other organizations in the form of graphical outputs of appropriate variants on the basis of solving a lot of criteria when searching for a suitable residence.
Land Use Change and Wildlife Conservation—Case Analysis of LULC Change of Pench-Satpuda Wildlife Corridor in Madhya Pradesh, India
Authors: Banerjee Sujoy , Kauranne Tuomo , Mikkila Mirja
Published: June 2020

To the burgeoning population, the tiger reserves of central India have been islanded by human habitation and are interconnected by narrow ‘wildlife corridors’ for migration of wildlife. Pench-Satpuda wildlife corridor is one such critical wildlife corridor that interconnects the Pench Tiger Reserve and Satpuda Tiger Reserve in central India. Land Use Land Cover (LULC) change of this corridor between April 2002 and April 2019 was analyzed using GIS and Remote Sensing Techniques. The study finds a systematic loss of 10,376.74 ha and 7406.24 ha of dense forests and open forests respectively, thus indicating large scale degradation of the area. The study found that a net area of 2054.60 of dense forests and open forests were diverted for agriculture indicating extensive encroachment of forest land. Water bodies have reduced by 25.41% indicating shrinkage in water bodies in the period under study. The presence of rich coal deposits in the wildlife corridor and operational coal mines in the near vicinity of the wildlife corridor is a matter of serious concern. This study attempts to highlight the importance of long-term sustenance of the Pench-Satpuda wildlife corridor for maintaining the genetic pool of wildlife in the landscape.
Using a Two-Stage DEA Model to Measure Tourism Potentials of EU Countries and Western Balkan Countries: An Approach to Sustainable Development
Authors: Radovanov Boris , Dudic Branislav , Gregus Michal , Marcikic Horvat Aleksandra , Karovic Vincent
Published: June 2020

The concept of sustainable tourism development is imposed as an inevitable way of improving the tourism industry as a whole. This study tries to offer an adequate inclusion of sustainable factors in overall tourism development efficiency results. Through the detection and estimation of potential sources of efficiency, the paper will do the efficiency benchmarking of tourism services on the level of countries as destinations. In order to complete the task, data collection was focused on 27 EU countries and five Western Balkan countries over the period from 2011 to 2017. This paper utilized an output-oriented data envelopment analysis (DEA) procedure to estimate efficiency scores for each country, and a panel data Tobit regression model to emphasize the (in)significance of each individual tourism development indicator. The results in the first stage show relatively high-efficiency scores, particularly in the case of EU 15 countries and with room for improvement in the case of the others. The second stage reveals positive and significant effects on relative tourism efficiency by the sustainability of tourism development, the share of GDP, tourist arrivals and inbound receipts, as well as visa requirements and rate of use. Policymakers should gradually take control of the mentioned variables to protect the interests of all relevant stakeholders involved in the tourism development process.
Beyond Economic Earnings: The Holistic Meaning of Success for Women in Agritourism
Authors: Halim M. Farzana , Barbieri Carla , Morais Duarte B. , Jakes Susan , Seekamp Erin
Published: June 2020

Women’s predominant role in agritourism expands their also significant involvement in agriculture and rural development. Yet, when measured in economic terms, women in agritourism appear to be less successful than men. We argue that economic earnings are a limited measure of success, as women value their accomplishments in a comprehensive and distinctive sense. To better understand women’s success in agritourism, we conducted a study addressing limitations in methodologies and scope of the existing scholarship. Framed within feminist and emic approaches, we used a combination of qualitative methods of inquiry (open-ended interviews, mini focus groups, nominal group exercises) to generate data from 20 female agritourism entrepreneurs in North Carolina (USA). Findings show women in agritourism define success through nine distinct themes, four of which are newly emerging (ensuring customer satisfaction, being constantly on the move, pursuing happiness, perpetuating the family farm). Participants also identified seven opportunities that they perceive contribute to their self-defined success. Our study adds to the scholarship and practice of gender in agritourism by expanding the economic definition of entrepreneurial success. In doing so, we provide managerial and policy intelligence that can be used to stimulate rural development.
Knowledge Transfer in Sustainable Contexts: A Comparative Analysis of Periods of Financial Recession and Expansion
Authors: Alos-Simo Lirios , Verdu-Jover Antonio J. , Gomez-Gras Jose M.
Published: June 2020

Examining the knowledge transfer process in sustainable contexts, we identified various gaps, which we analyzed in this study. First, we compare the temporal context of firms with eco-innovation strategies before and after the financial crisis of the first decade of the 21st century. Second, we analyze the firms’ knowledge transfer, from the use of knowledge sources to innovation through intellectual property. Third, we consider the influence of firm age on firms with eco-innovation goals and the influence of size on intellectual property. We used data from a sample of 3004 firms prepared by the Spanish National Statistics Institute for two different time periods: 2009 and 2014. Our results suggest that firms that achieve sustainable innovations do not show large differences in behavior in the two economic periods. We found that knowledge in firms with eco-innovation goals is transferred through intellectual property. The results show that firm age and size influence these processes during the years analyzed and thus have various implications for theory and for small firms, which are generally family firms. Small and family firms should strengthen their registration of intellectual property so that their knowledge transfer process ends in innovations for both the firm and the market.
How Does Operational Environment Influence Public Transport Effectiveness? Evidence from European Urban Bus Operators
Authors: Georgiadis Georgios , Politis Ioannis , Papaioannou Panagiotis
Published: June 2020

Public transport systems’ effectiveness is a well-recognized pillar of their sustainability. In this study, we employed order-m efficiency estimators to investigate the effectiveness of 57 bus public transport operators that provide services in both large and medium sized European cities. Their effectiveness was simulated through a tailored production model and was evaluated against critical exogenous variables, which were mostly extracted from Eurostat database. Results showed that the effectiveness of the examined operators is generally satisfactory. Our research suggests that certain exogenous factors significantly affect operators’ effectiveness and thus create either advantageous or disadvantageous operational environments for maintaining public transport sustainability. Among these factors, household size, unemployment and car ownership rates were found to be unfavorable to bus public transport operations. Contrary to them, the presence of university students and metro systems in cities create a favorable operational environment for bus public transport effectiveness. These findings assist in the identification of sustainable development policies that would both contribute to public transport sustainability and to the fulfillment of wider community goals. Our findings also rationalize benchmarking exercises in the public transport industry, since they enable fair performance comparisons between systems that seek to incorporate successful management practices to improve their sustainability.
Video Caption Based Searching Using End-to-End Dense Captioning and Sentence Embeddings
Authors: Aggarwal Akshay , Chauhan Aniruddha , Kumar Deepika , Mittal Mamta , Roy Sudipta , Kim Tai-hoon
Published: June 2020

Traditionally, searching for videos on popular streaming sites like YouTube is performed by taking the keywords, titles, and descriptions that are already tagged along with the video into consideration. However, the video content is not utilized for searching of the user’s query because of the difficulty in encoding the events in a video and comparing them to the search query. One solution to tackle this problem is to encode the events in a video and then compare them to the query in the same space. A method of encoding meaning to a video could be video captioning. The captioned events in the video can be compared to the query of the user, and we can get the optimal search space for the videos. There have been many developments over the course of the past few years in modeling video-caption generators and sentence embeddings. In this paper, we exploit an end-to-end video captioning model and various sentence embedding techniques that collectively help in building the proposed video-searching method. The YouCook2 dataset was used for the experimentation. Seven sentence embedding techniques were used, out of which the Universal Sentence Encoder outperformed over all the other six, with a median percentile score of 99.51. Thus, this method of searching, when integrated with traditional methods, can help improve the quality of search results.
A New Objective Function for the Recovery of Gielis Curves
Authors: Arce Alejandro Marcelo , Caroni Gabriel Giovanni , Vázquez Noguera José Luis , Pinto-Roa Diego P. , Legal-Ayala Horacio , Grillo Sebastián A.
Published: June 2020

The superformula generates curves called Gielis curves, which depend on a small number of input parameters. Recovering parameters generating a curve that adapts to a set of points is a non-trivial task, thus methods to accomplish it are still being developed. These curves can represent a great variety of forms, such as living organisms, objects and geometric shapes. In this work we propose a method that uses a genetic algorithm to minimize a combination of three objectives functions: Euclidean distances from the sample points to the curve, from the curve to the sample points and the curve length. Curves generated with the parameters obtained by this method adjust better to real curves in relation to the state of art, according to observational and numeric comparisons.
Synergistic Effects in a ZnO Powder-Based Coating Sequentially Irradiated with Protons, Electrons, and Solar Spectrum Quanta
Authors: Mikhailov Mikhail M. , Yuryev Semyon A. , Lapin Alexey N. , Karanskiy Vadim V.
Published: June 2020

The authors investigated the changes in diffuse reflectance spectra (ρλ) within 0.32–2.1 μm and integral absorption coefficient (as) of solar irradiation for a zinc oxide powder-based coating. The latter was consequently irradiated with protons (E = 3 keV, F ≤ 1 × 1016 cm−2), solar spectrum quanta (5 eq. of solar irradiation, 1 h), electrons (E = 30 keV, F = 1 × 1016 cm−2), and—repetitively—solar spectrum quanta (5 eq. of solar irradiation, 1 h). Following the irradiation procedure, the decrease in absorption coefficient varied from 0.044 to 0.036 and from 0.062 to 0.04, respectively. Additionally, it was shown that the solar spectrum quanta did not significantly affect the coating pre-irradiated with protons or electrons and did not change the value of induced absorption in the visible region (the latter being caused by the absorption of intrinsic point defects of the zinc oxide crystal lattice). The absorption coefficient degradation decreased under solar spectrum quanta irradiation, which was determined by the decrease in the concentration of free electrons that absorbed in the near-infrared (near-IR) region. ρλ spectra were measured in high vacuum in situ. A post-irradiation transfer of a coating into the atmosphere leads not only to the complete recovery of its reflectance, but also to partial translucence in comparison with the non-irradiated state.
Challenges Associated with Implementing 5G in Manufacturing
Authors: O’Connell Eoin , Moore Denis , Newe Thomas
Published: June 2020

5G networks will change several industries, including manufacturing. 5G has the potential to become the future communication platform of choice for many industries and in particular the manufacturing sector, driving the future of Industry 4.0 and smart manufacturing. The vision of a “factory of the future” is now tangible for many industry sectors. The ability to cope with increased bandwidth, latency requirements, big-data generated from more connected equipment and the data processing required on the factory floor is a massive challenge for industry. This paper discusses how 5G can impact a manufacturing environment, the standards and technical requirements needed to meet the demands of utilizing 5G, and the security issues that need to be addressed if planning a 5G deployment.
Potential Cause of Decrease in Bloom Events of the Harmful Dinoflagellate Cochlodinium polykrikoides in Southern Korean Coastal Waters in 2016
Authors: Baek Seung Ho , Kim Yunji , Lee Minji , Ahn Chi-Yong , Cho Kyung Hwa , Park Bum Soo
Published: June 2020

Blooms of the ichthyotoxic dinoflagellate Cochlodinium polykrikoides are responsible for massive fish mortality events in Korean coastal waters (KCW). They have been consistently present in southern KCW over the last two decades, but they were not observed in 2016, unlike in the previous years. Despite extensive studies, the cause of this absence of this dinoflagellate bloom remains largely unknown. Thus, we compared physico-chemical and biological data from along the Tongyeong coast between 2016 and the previous four years (2012–2015). The averages of water temperature and salinity in August, 2016 were significantly (p < 0.001) different from those in the previous years. The amount of Changjiang River discharge, which can affect the environmental conditions in the southern Korean coastal area via ocean currents, was larger than in the previous years, resulting in a reduction in the salinity level in August when blooms of C. polykrikoides usually occurred. Moreover, compared to previous years, in 2016, there was a weak expansion of C. polykrikoides blooms in the Goheung-Oenarodo area where C. polykrikoides blooms were annually initiated in KCW. Lastly, the strong winds from the typhoon Lionrock may also have contributed to the early termination of this dinoflagellate bloom. Together with these findings, the combination of these environmental conditions in 2016, unlike in previous years, may have inhibited the formation of C. polykrikoides blooms along the Tongyeong coast.
Efficacy and Safety of Botulinum Toxin Type A on Persistent Myofascial Pain: A Randomized Clinical Trial
Authors: De la Torre Canales Giancarlo , Alvarez-Pinzon Natalia , Muñoz-Lora Victor Ricardo Manuel , Vieira Peroni Leonardo , Farias Gomes Amanda , Sánchez-Ayala Alfonso , Haiter-Neto Francisco , Manfredini Daniele , Rizzatti-Barbosa Célia Marisa
Published: June 2020

This study assessed the safety and efficacy of three different doses of BoNT-A for persistent myofascial pain (MFP). One hundred female subjects were randomly assigned into five groups (n = 20): oral appliance (OA), saline solution (SS) and three BoNT-A groups with different doses. Pain intensity and pressure pain threshold were evaluated up to 24 weeks after treatment. Adverse effects related to muscle contraction, masticatory performance, muscle thickness and mandibular bone volume were also assessed. Changes over time were compared within and between groups. The “nparLD” package and Wilcoxon signed-rank test were used to analyze the data. BoNT-A reduced pain intensity (p < 0.0001) and increased pressure pain threshold (p < 0.0001) for up to 24 weeks compared to the placebo. No differences were found between BoNT-A and OA at the last follow-up. A transient decline in masticatory performance (p < 0.05) and muscle contraction (p < 0.0001), and a decrease in muscle thickness (p < 0.05) and coronoid and condylar process bone volume (p < 0.05) were found as dose-related adverse effects of BoNT-A. Regardless of the dose, BoNT-A was as effective as OA on MFP. Notwithstanding, due to BoNT-A dose-related adverse effects, we suggest the use of low doses of BoNT-A in MFP patients that do not benefit from conservative treatments.
Mapping the Daily Rainfall over an Ungauged Tropical Micro-Watershed: A Downscaling Algorithm Using GPM Data
Authors: Mahmud Mohd. Rizaludin , Mohd Yusof Aina Afifah , Mohd Reba Mohd Nadzri , Hashim Mazlan
Published: June 2020

In this study, half-hourly Global Precipitation Mission (GPM) satellite precipitation data were downscaled to produce high-resolution daily rainfall data for tropical coastal micro-watersheds (100–1000 ha) without gauges or with rainfall data conflicts. Currently, daily-scale satellite rainfall downscaling techniques rely on rain gauge data as corrective and controlling factors, making them impractical for ungauged watersheds or watersheds with rainfall data conflicts. Therefore, we used high-resolution local orographic and vertical velocity data as proxies to downscale half-hourly GPM precipitation data (0.1°) to high-resolution daily rainfall data (0.02°). The overall quality of the downscaled product was similar to or better than the quality of the raw GPM data. The downscaled rainfall dataset improved the accuracy of rainfall estimates on the ground, with lower error relative to measured rain gauge data. The average error was reduced from 41 to 27 mm/d and from 16 to 12 mm/d during the wet and dry seasons, respectively. Estimates of localized rainfall patterns were improved from 38% to 73%. The results of this study will be useful for production of high-resolution satellite precipitation data in ungauged tropical micro-watersheds.
A Systems Approach to Municipal Water Portfolio Security: A Case Study of the Phoenix Metropolitan Area
Authors: Rushforth Richard R. , Messerschmidt Maggie , Ruddell Benjamin L.
Published: June 2020

We present a rigorous quantitative, systems-based model to measure a municipality’s water portfolio security using four objectives: Sustainability, Resilience, Vulnerability, and Cost (SRVC). Water engineers and planners can operationalize this simple model using readily available data to capture dimensions of water security that go far beyond typical reliability and cost analysis. We implement this model for the Phoenix Metropolitan Area under several scenarios to assess multi-objective water security outcomes at the municipal-level and metropolitan area-level to water shocks and drought. We find the benefits of adaptive water security policies are dependent on a municipality’s predominant water source, calling for a variegated approach to water security planning across a tightly interrelated metropolitan area. Additionally, we find little correlation between sustainability, resilience, and vulnerability versus cost. Therefore, municipalities can enhance water security along cost-neutral, adaptive policy pathways. Residential water conservation and upstream flow augmentation are cost-effective policies to improve water security that also improve sustainability, resilience, and vulnerability and are adequate adaptations to a short-term Colorado River shortage. The Phoenix Metropolitan Area’s resilience to drought is higher than that of any of its constituent municipalities, underscoring the benefits of coordinated water planning at the metropolitan area-level.
Drivers of Benthic Macroinvertebrate Assemblages in Equatorial Alpine Rivers of the Rwenzoris (Uganda)
Authors: Musonge Peace S.L. , Boets Pieter , Lock Koen , Goethals Peter L.M.
Published: June 2020

The Sub-Saharan alpine freshwater biodiversity is currently impacted by human settlements, climate change, agriculture, and mining activities. Because of the limited biodiversity studies in the region, a better understanding is needed of the important environmental variables affecting macroinvertebrate assemblages. In this paper, macroinvertebrate diversity responses to 18 environmental variables were studied at 30 sites along unique Rwenzori rivers at the equator in Uganda. We hypothesized that anthropogenic disturbance and local environmental variables affect macroinvertebrate diversity, irrespective of altitudinal gradients. Based on altitude and climate, the sites were subdivided into three altitude groups consisting of 10 sites each: upstream (US) 1400–1600 m.a.s.l.; midstream (MS) 1091–1399 m.a.s.l., and downstream (DS) 900–1090 m.a.s.l. A total of 44 macroinvertebrate families and 1623 individuals were identified. The macroinvertebrate diversity patterns were influenced by temperature, altitude, and latitude. Regression analysis revealed that temperature and nickel, were negative predictors of taxa richness. Nickel, which is released by mining activity, is detrimental to aquatic communities in Sub-Saharan alpine ecosystems. Significant longitudinal variation in macroinvertebrate diversity was observed between the sites, which were also affected by mineral and temperature gradients. Our study highlights the need for long-term monitoring in this region to detect and reduce the threats to river biodiversity from anthropogenic activity.
Comparison of ERA5-Land and UERRA MESCAN-SURFEX Reanalysis Data with Spatially Interpolated Weather Observations for the Regional Assessment of Reference Evapotranspiration
Authors: Pelosi Anna , Terribile Fabio , D’Urso Guido , Chirico Giovanni
Published: June 2020

Reanalysis data are being increasingly used as gridded weather data sources for assessing crop-reference evapotranspiration (ET0) in irrigation water-budget analyses at regional scales. This study assesses the performances of ET0 estimates based on weather data, respectively produced by two high-resolution reanalysis datasets: UERRA MESCAN-SURFEX (UMS) and ERA5-Land (E5L). The study is conducted in Campania Region (Southern Italy), with reference to the irrigation seasons (April–September) of years 2008–2018. Temperature, wind speed, vapor pressure deficit, solar radiation and ET0 derived from reanalysis datasets, were compared with the corresponding estimates obtained by spatially interpolating data observed by a network of 18 automatic weather stations (AWSs). Statistical performances of the spatial interpolations were evaluated with a cross-validation procedure, by recursively applying universal kriging or ordinary kriging to the observed weather data. ERA5-Land outperformed UMS both in weather data and ET0 estimates. Averaging over all 18 AWSs sites in the region, the normalized BIAS (nBIAS) was found less than 5% for all the databases. The normalized RMSE (nRMSE) for ET0 computed with E5L data was 17%, while it was 22% with UMS data. Both performances were not far from those obtained by kriging interpolation, which presented an average nRMSE of 14%. Overall, this study confirms that reanalysis can successfully surrogate the unavailability of observed weather data for the regional assessment of ET0.
Evaluation of the Storage Effect Considering Possible Redevelopment Options of the Peace Dam in South Korea
Authors: Yoo Chulsang , Shin Hyunsun , Lee Jinwook
Published: June 2020

The Peace Dam is one of two flood control dams in South Korea. Located near the demilitarized zone (DMZ) between North and South Korea, the Peace Dam was constructed as a counter measure to the Imnam Dam of North Korea. However, the recent reconciliation efforts between North and South Korea have raised the possibility for the redevelopment of the Peace Dam to be a multi-purpose dam. This study evaluates the possible increase of the flood control ability of the Peace Dam under the condition of its redevelopment. The allocation of flood control and water conservation storage as well as the reservoir operation method is determined to follow the other similar-sized dams in Korea. The flood control ability is quantified by introducing the concept of a storage coefficient. In order to estimate the storage coefficient, an exponential nonlinear reservoir model was used. The results can be summarized as follows: First, the current Peace Dam, a flood control dam, is found to have a small flood control ability. Quantified by the storage coefficient, the flood control ability of the current Peace Dam is estimated to be just 3.9 h. Second, the maximum storage coefficient of the Peace Dam can be increased up to 22.6 h. Here, it is assumed that the dam is operated by the rigid reservoir operation method (rigid ROM) in which the discharge is determined by applying a constant rate (specifically, 0.5 in this study) to the inflow until the peak inflow is reached. In addition, this result is based on the assumption that the ratio between water conservation storage and flood control storage is three. That is, even though the flood control storage is set at just 25% of the total storage, the storage coefficient is increased to be more than five times that of the current Peace Dam. In addition, secured water conservation storage can significantly increase the benefits associated with the redevelopment of the Peace Dam.
A Socio-Ecological System Analysis of Multilevel Water Governance in Nicaragua
Authors: Montenegro Luis , Hack Jochen
Published: June 2020

Nicaragua enacted its Water Law in 2007, with the Dublin Principles for sustainable water management and integrated water resources management as its guiding framework. Implementation of the law remains a challenge, but significant efforts have been made to roll out this new water resources framework, to improve water management by enhancing a multilevel water governance system. To analyze multilevel water governance in Nicaragua and diagnose stakeholders’ roles and compliance with the law, we applied a socio-ecological system framework and several methods of analysis to process data collected from 52 in-depth semistructured interviews conducted with key stakeholders in the water sector. We found that the major variables affecting multilevel water governance were social interests, administrative capacity, and political, economic, and legal arrangements. The results suggest that there is centralization at the national level, a tendency toward noncollective choice rules, little investment in water resources, and a lack of knowledge concerning conflict resolution mechanisms. For multilevel water governance, a lack of funds is the main social, economic, and political constraint, affecting interactions and outcomes. Nevertheless, there is great potential to improve water resource management in Nicaragua by enacting the self-funding schemes established in the law. Moreover, government institutions, users, and various networks are willing to participate and take action to implement the law.
Model Test of the Effect of River Sinuosity on Nitrogen Purification Efficiency
Authors: Xiao Chenguang , Chen Jing , Yuan Xianjiang , Chen Ruidong , Song Xia
Published: June 2020

River pollution is a significant problem within the urbanization process in China. Nitrogen is one of the most important pollutants in rivers, and the nitrogen purification capacity of rivers can be affected by their sinuous morphology. In this study, a set of sandy circulating water test models was constructed, consisting of four river channel simulation models with sinuosities of 1.0, 1.4, 1.8, and 2.2. Each model was then infused with the same concentration of nitrogen-polluted water, which circulated for 52 h. The nitrogen reduction processes of rivers with different sinuosities were studied through water quality monitoring. The positive correlation between river sinuosity and nitrogen purification capacity was verified in physical laboratory test models. The effect of sinuosity on the spatiotemporal distribution of total nitrogen in pore water was confirmed. Additionally, the near-shore substrate was more involved in the process of river self-purification than the far-shore substrate. The concave bank of the sinuous rivers was more prone to pollutant accumulation and had a higher purification capacity than the convex bank. After the polluted water entered the sinuous channel systems, pollutant concentration differed within the convex bank between the more polluted upstream section and the less polluted downstream section. This study lays a foundation for studying the mechanism by which river sinuosity influences self-purification capacity.
Impact of Climate Change on Nearshore Waves at a Beach Protected by a Barrier Reef
Authors: de Lalouvière Claude la Hausse , Gracia Vicente , Sierra Joan Pau , Lin-Ye Jue , García-León Manuel
Published: June 2020

Barrier reefs dissipate most incoming wind-generated waves and, as a consequence, regulate the morphodynamics of its inbounded shorelines. The coastal protective capacity of reefs may nevertheless be compromised by climate change effects, such as reef degradation and sea-level rise. To assess the magnitude of these climate change effects, an analysis of the waves propagating across the barrier reef is carried out in Flic-en-Flac beach, Mauritius, based on scenarios of future sea levels and predicted coral reef condition. In the study, both the mean wave climate and extreme event conditions are considered. The results show that lower coral structure complexity jointly with higher water levels allow for higher waves to pass over the reef and, therefore, to reach the shoreline. In addition, modeling for cyclonic conditions showed that nearshore waves would also increase in height, which could lead to major coastal morphodynamic changes. Measures aimed at preserving the coral reef may allow the system to accommodate for the gradual climatic changes forecasted while keeping its coastal protective function.
Nitrifying and Denitrifying Microbial Communities in Centralized and Decentralized Biological Nitrogen Removing Wastewater Treatment Systems
Authors: Wigginton Sara K. , Brannon Elizabeth Q. , Kearns Patrick J. , Lancellotti Brittany V. , Cox Alissa , Moseman-Valtierra Serena , Loomis George W. , Amador Jose A.
Published: June 2020

Biological nitrogen removal (BNR) in centralized and decentralized wastewater treatment systems is assumed to be driven by the same microbial processes and to have communities with a similar composition and structure. There is, however, little information to support these assumptions, which may impact the effectiveness of decentralized systems. We used high-throughput sequencing to compare the structure and composition of the nitrifying and denitrifying bacterial communities of nine onsite wastewater treatment systems (OWTS) and one wastewater treatment plant (WTP) by targeting the genes coding for ammonia monooxygenase (amoA) and nitrous oxide reductase (nosZ). The amoA diversity was similar between the WTP and OWTS, but nosZ diversity was generally higher for the WTP. Beta diversity analyses showed the WTP and OWTS promoted distinct amoA and nosZ communities, although there is a core group of N-transforming bacteria common across scales of BNR treatment. Our results suggest that advanced N-removal OWTS have microbial communities that are sufficiently distinct from those of WTP with BNR, which may warrant different management approaches.
Does the Process of Passive Forest Restoration Affect the Hydrophysical Attributes of the Soil Superficial Horizon?
Authors: Pereira Nayana Alves , Di Prima Simone , Bovi Renata Cristina , da Silva Laura Fernanda Simões , de Godoy Gustavo , Naves Rafaela Pereira , Cooper Miguel
Published: June 2020

There has been an increase in the area of secondary tropical forests in recent years due to forest restoration in degraded areas. Recent analyses suggest that the success of passive forest restoration is highly uncertain and needs to be better understood. This study aimed to investigate the behavior of saturated hydraulic conductivity (Ks) and some hydrophysical soil attributes between agricultural land uses, restored forests, and a degraded forest fragment. The areas evaluated are located in the municipality of Rio Claro, São Paulo, Brazil, under different types of land use: (i) two areas in the process of passive forest restoration: one of 18 and another of 42 years (NR18 and NR42); (ii) a degraded forest fragment (FFD); (iii) pasture (P), and (iv) sugarcane (SC). The hydraulic soil conductivity characterization was performed using the Beerkan method. Dry soil bulk density (BD), total porosity (Pt), macroporosity (Mac), microporosity (Mic), penetration resistance (PR), mean aggregate diameter (MWD), and soil organic carbon (OC) were also determined. The comparative analysis of the hydrophysical attributes of the soil superficial horizon in agricultural land uses (P and SC), restored forests (NR18 and NR42), and a degraded forest (DFF) confirms that the recovery of soil hydrological functioning in ongoing forest restoration processes can be a relatively slow process. In addition, the intensity of previous land use leaves footprints that can affect passive restoration areas for decades after agriculture abandonment, increasing the time for the recovery of Ks and soil hydrophysical attributes.
Characteristics and Causes of Long-Term Water Quality Variation in Lixiahe Abdominal Area, China
Authors: Jiang Chenjuan , Zhou Jia’nan , Wang Jingcai , Fu Guosheng , Zhou Jiren
Published: June 2020

The Lixiahe abdominal area is a representative plain river network in the lower reaches of the Huai River, being an upstream section of south-to-north water diversion from the Yangtze River in Jiangsu Province, China. The assessment of long-term water quality variation and the identification of probable causes can provide references for sustainable water resources management. Based on the monthly water quality data of 15 monitoring stations in the Lixiahe abdominal area, the periodic characteristics and tendency of water quality variation were studied by combining wavelet analysis, the Mann–Kendall trend test, and Sen’s slope estimator, and the correlation between water quality variation, water level, and water diversion was discussed with cross wavelet transform and wavelet coherence. The results show that the comprehensive water quality index (CWQI) included periodic fluctuations on multiple scales from 0.25 to 5 years. The CWQI of 7 out of 15 monitoring stations has a significant decreasing trend, indicating regional water quality improvement. The trend slope ranges from −0.071/yr to 0.007/yr, where −0.071/yr indicates the water quality improvement by one grade in 15 years. The spatial variation of water quality in the Lixiahe abdominal area was significant. The water quality of the main water diversion channels and its nearby rivers was significantly improved, while the improvement of other areas was not significant or even became worse due to the increasing discharge of pollutants. The CWQI of the main water diversion channels and its nearby rivers was inversely correlated with the amount of water diversion. The greater the amount of water diversion, the better the water quality. The water diversion from the Yangtze River has played an important role in improving the regional water environment.
Wave Overtopping Discharge for Very Gently Sloping Foreshores
Authors: Nguyen Thu-Ha , Hofland Bas , Dan Chinh Vu , Stive Marcel
Published: June 2020

The spectral wave period T m − 1 , 0 at the toe of sea-dikes is a crucial parameter to predict wave overtopping discharge over sea-dikes. It is known from literature that this period quickly increases when waves reach shallow foreshores; however, sometimes the assumption is made that the wave period remains constant from offshore to near-shore, leading to an underestimation of the near-shore wave period. Several formulae have been proposed to resolve the underestimation of wave overtopping discharges for very shallow foreshores. These corrective formulations confirm the tendency of underestimating the overtopping discharges over a very gently sloping foreshore but are not validated for foreshore slopes gentler than 1:500. The “equivalent slope” method based on a recent study is inappropriate for these very gently sloping foreshores due to the breaker parameter being much smaller than seven. This study proposes an extension of the correction and finds that spectral wave periods can reach values two times those offshore.
Pier Scour Prediction in Non-Uniform Gravel Beds
Authors: Pandey Manish , Oliveto Giuseppe , Pu Jaan H. , Sharma P. K. , Ojha C. S. P.
Published: June 2020

Pier scour has been extensively studied in laboratory experiments. However, scour depth relationships based on data at the laboratory scale often yield unacceptable results when extended to field conditions. In this study, non-uniform gravel bed laboratory and field datasets with gravel of median size ranging from 2.7 to 14.25 mm were considered to predict the maximum equilibrium scour depth at cylindrical piers. Specifically, a total of 217 datasets were collected: 132 from literature sources and 85 in this study using new experiments at the laboratory scale, which constitute a novel contribution provided by this paper. From the analysis of data, it was observed that Melville and Coleman’s equation performs well in the case of laboratory datasets, while it tends to overestimate field measurements. Guo’s and Kim et al.’s relationships showed good agreements only for laboratory datasets with finer non-uniform sediments: deviations in predicting the maximum scour depth with non-uniform gravel beds were found to be significantly greater than those for non-uniform sand and fine gravel beds. Consequently, new K-factors for the Melville and Coleman’s equation were proposed in this study for non-uniform gravel-bed streams using a curve-fitting method. The results revealed good agreements between observations and predictions, where this might be an attractive advancement in overcoming scale effects. Moreover, a sensitivity analysis was performed to identify the most sensitive K-factors.
Baseline Conditions and Projected Future Hydro-Climatic Change in National Parks in the Conterminous United States
Authors: Battaglin William , Hay Lauren , Lawrence David , McCabe Greg , Norton Parker
Published: June 2020

The National Park Service (NPS) manages hundreds of parks in the United States, and many contain important aquatic ecosystems and/or threatened and endangered aquatic species vulnerable to hydro-climatic change. More effective management of park resources under future hydro-climatic uncertainty requires information on both baseline conditions and the range of projected future conditions. A monthly water balance model was used to assess baseline (1981–1999) conditions and a range of projected future hydro-climatic conditions in 374 NPS parks. General circulation model outputs representing 214 future climate simulations were used to drive the model. Projected future changes in air temperature (T), precipitation (p), and runoff (R) are expressed as departures from historical baselines. Climate simulations indicate increasing T by 2030 for all parks with 50th percentile simulations projecting increases of 1.67 °C or more in 50% of parks. Departures in 2030 p indicate a mix of mostly increases and some decreases, with 50th percentile simulations projecting increases in p in more than 70% of parks. Departures in R for 2030 are mostly decreases, with the 50th percentile simulations projecting decreases in R in more than 50% of parks in all seasons except winter. Hence, in many NPS parks, R is projected to decrease even when p is projected to increase because of increasing T in all parks. Projected changes in future hydro-climatic conditions can also be assessed for individual parks, and Rocky Mountain National Park and Congaree National Park are used as examples.
Desalination of Seawater for Agricultural Irrigation
Authors: Martinez-Alvarez Victoriano , Bar-Tal Asher , Diaz Peña Francisco Javier , Maestre-Valero Jose F.
Published: June 2020

Food security concerns, climate change impacts, and increased pressure on conventional water resources have encouraged the agricultural use of nonconventional water resources in the last decade. As a result, desalinated seawater (DSW) has already consolidated its position as an alternative source to increase the supply for crop irrigation in Spain and Israel, where farmers’ acceptance is progressively on the rise. The first experiences in these regions highlighted that DSW agricultural use involves new agronomic, economic, and environmental challenges which require innovative research approaches and imply novel water management strategies. In this Special Issue, eight high-quality papers which present current research trials and study cases, covering a wide range of topics that are relevant when irrigating with DSW, have been selected. The papers came from the three regions of the world that currently have a massive agricultural DSW supply: Southeastern Spain, Israel, and the Canary Islands.
UAV-DEMs for Small-Scale Flood Hazard Mapping
Authors: Annis Antonio , Nardi Fernando , Petroselli Andrea , Apollonio Ciro , Arcangeletti Ettore , Tauro Flavia , Belli Claudio , Bianconi Roberto , Grimaldi Salvatore
Published: June 2020

Devastating floods are observed every year globally from upstream mountainous to coastal regions. Increasing flood frequency and impacts affect both major rivers and their tributaries. Nonetheless, at the small-scale, the lack of distributed topographic and hydrologic data determines tributaries to be often missing in inundation modeling and mapping studies. Advances in Unmanned Aerial Vehicle (UAV) technologies and Digital Elevation Models (DEM)-based hydrologic modeling can address this crucial knowledge gap. UAVs provide very high resolution and accurate DEMs with low surveying cost and time, as compared to DEMs obtained by Light Detection and Ranging (LiDAR), satellite, or GPS field campaigns. In this work, we selected a LiDAR DEM as a benchmark for comparing the performances of a UAV and a nation-scale high-resolution DEM (TINITALY) in representing floodplain topography for flood simulations. The different DEMs were processed to provide inputs to a hydrologic-hydraulic modeling chain, including the DEM-based EBA4SUB (Event-Based Approach for Small and Ungauged Basins) hydrologic modeling framework for design hydrograph estimation in ungauged basins; the 2D hydraulic model FLO-2D for flood wave routing and hazard mapping. The results of this research provided quantitative analyses, demonstrating the consistent performances of the UAV-derived DEM in supporting affordable distributed flood extension and depth simulations.