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Water, Volume 11, Issue 9 (September 2019) – 218 articles

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Cover Story (view full-size image) Understanding interactions between strongly connected groundwater and surface water is important [...] Read more.
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Open AccessArticle
Concentration Measurement of Uniform Particles Based on Backscatter Sensing of Optical Fibers
Water 2019, 11(9), 1955; https://doi.org/10.3390/w11091955 - 19 Sep 2019
Cited by 1 | Viewed by 859
Abstract
A set of miniature optical fiber particle concentration measuring instruments is designed and applied to develop a unified expression for the concentration measurement of uniform particles in tap water. By measuring the concentrations of six uniform silicon carbide particles in the size range [...] Read more.
A set of miniature optical fiber particle concentration measuring instruments is designed and applied to develop a unified expression for the concentration measurement of uniform particles in tap water. By measuring the concentrations of six uniform silicon carbide particles in the size range of 38–250 μm, the unified relationship between particle size, particle concentration, and optical scattering intensity is proposed. The unified expression is verified by the concentration measurements of silicon carbide particles with three other sizes. The results show that the measurement error is less than 10%, and the unified expression is satisfactory considering the large measuring range of 0–50 kg/m3. The effects of light intensity on the concentration measurement are discussed based on the results of 150 μm silicon carbide particles under three different light intensities. It is shown that a low light intensity can be applied for high-concentration measurement with relatively low accuracy, while a high light intensity can be adopted for low-concentration measurement with higher accuracy. Full article
(This article belongs to the Section Hydraulics and Hydrodynamics)
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Open AccessArticle
Pseudo-nitzschia Blooms in a Coastal Upwelling System: Remote Sensing Detection, Toxicity and Environmental Variables
Water 2019, 11(9), 1954; https://doi.org/10.3390/w11091954 - 19 Sep 2019
Cited by 3 | Viewed by 938
Abstract
The NW coast of the Iberian Peninsula is dominated by extensive shellfish farming, which places this region as a world leader in mussel production. Harmful algal blooms in the area frequent lead to lengthy harvesting closures threatening food security. This study developed a [...] Read more.
The NW coast of the Iberian Peninsula is dominated by extensive shellfish farming, which places this region as a world leader in mussel production. Harmful algal blooms in the area frequent lead to lengthy harvesting closures threatening food security. This study developed a framework for the detection of Pseudo-nitzschia blooms in the Galician rias from satellite data (MERIS full-resolution images) and identified key variables that affect their abundance and toxicity. Two events of toxin-containing Pseudo-nitzschia were detected (up to 2.5 μg L−1 pDA) in the area. This study suggests that even moderate densities of Pseudo-nitzschia in this area might indicate high toxin content. Empirical models for particulate domoic acid (pDA) were developed based on MERIS FR data. The resulting remote-sensing model, including MERIS bands centered around 510, 560, and 620 nm explain 73% of the pDA variance (R2 = 0.73, p < 0.001). The results show that higher salinity values and lower Si(OH)4/N ratios favour higher Pseudo-nitzschia spp. abundances. High pDA values seem to be associated with relatively high PO43, low NO3 concentrations, and low Si(OH)4/N. While MERIS FR data and regionally specific algorithms can be useful for detecting Pseudo-nitzschia blooms, nutrient relationships are crucial for predicting the toxicity of these blooms. Full article
(This article belongs to the Special Issue Application of Remote Sensing and GIS in Aquatic Ecosystems)
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Open AccessArticle
Spatio-Temporal Groundwater Drought Monitoring Using Multi-Satellite Data Based on an Artificial Neural Network
Water 2019, 11(9), 1953; https://doi.org/10.3390/w11091953 - 19 Sep 2019
Cited by 2 | Viewed by 958
Abstract
Drought is a complex phenomenon caused by lack of precipitation that affects water resources and human society. Groundwater drought is difficult to assess due to its complexity and the lack of spatio-temporal groundwater observations. In this study, we present an approach to evaluate [...] Read more.
Drought is a complex phenomenon caused by lack of precipitation that affects water resources and human society. Groundwater drought is difficult to assess due to its complexity and the lack of spatio-temporal groundwater observations. In this study, we present an approach to evaluate groundwater drought based on relatively high spatial resolution groundwater storage change data. We developed an artificial neural network (ANN) that employed satellite data (Gravity Recovery and Climate Experiment (GRACE) and Tropical Rainfall Measuring Mission (TRMM)) as well as Global Land Data Assimilation System (GLDAS) models. The Standardized Groundwater Level Index (SGI) was calculated by normalizing ANN-predicted groundwater storage changes from 2003 to 2015 across South Korea. The ANN-predicted 25 km groundwater storage changes correlated well with both the in situ and the water balance equation (WBE)-estimated groundwater storage changes, with mean correlation coefficients of 0.87 and 0.64, respectively. The Standardized Precipitation–Evapotranspiration Index (SPEI), having an accumulation time of 1–6 months, and the Palmer Drought Severity Index (PDSI) were used to validate the SGI. The results showed that the SGI had a pattern similar to that of SPEI-1 and SPEI-2 (1- and 2-month accumulation periods, respectively), and PDSI. However, the SGI performance fluctuated slightly due to its relatively short study period (13 years) as compared to SPEI and PDSI (more than 30 years). The SGI, which was developed using a new approach in this study, captured the characteristics of groundwater drought, thus presenting a framework for the assessment of these characteristics. Full article
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Open AccessEditor’s ChoiceArticle
Sustainable Irrigation Using Non-Conventional Resources: What has Happened after 30 Years Regarding Boron Phytotoxicity?
Water 2019, 11(9), 1952; https://doi.org/10.3390/w11091952 - 19 Sep 2019
Cited by 4 | Viewed by 765
Abstract
In the Canary Islands, there is a hydrological imbalance between water consumption and renewable water availability. To provide more water resources, reverse osmosis (RO) from seawater is used. As boron (B) contents in irrigation water higher than 0.7 mg/L may be dangerous for [...] Read more.
In the Canary Islands, there is a hydrological imbalance between water consumption and renewable water availability. To provide more water resources, reverse osmosis (RO) from seawater is used. As boron (B) contents in irrigation water higher than 0.7 mg/L may be dangerous for sensible plants, B concentration in RO water (ROW) may be one of the key factors of irrigation sustainability. Some orchards have been studied after they have used drip irrigation using different water qualities for 30 years. B in water, soils, and banana leaves was determined to check the sustainability of ROW irrigation. When irrigating with ROW, in which B concentration varies between 1.0 and 1.4 mgB/L, B content in banana soils seems to be stabilized at 5–7 mg/kg, and no toxicity has been observed in banana leaves. The proper water and soil management used by the local farmers probably prevent the accumulation of higher B levels in soils. Considering water consumption of 9000 m3∙ha−1∙year−1, 8−11 kgB∙ha−1∙year−1 is applied to the soil. The banana plant removes approximately 1 kgB∙ha−1∙year−1; therefore, only 10% of the total B added gets exported. This raises the following question: is it better to use membranes that are able to reduce B in ROW, increase the leaching fraction, or blend water? Full article
(This article belongs to the Special Issue Desalination of Seawater for Agricultural Irrigation)
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Open AccessArticle
Hydro-Meteorological Trends in the Upper Omo-Ghibe River Basin, Ethiopia
Water 2019, 11(9), 1951; https://doi.org/10.3390/w11091951 - 19 Sep 2019
Cited by 3 | Viewed by 820
Abstract
This study aimed to assess trends of hydro-meteorological variables in the Upper Omo-Ghibe river basin, Ethiopia. Data records from eleven rainfall, eight air temperature, and five streamflow stations between 1981 to 2008 were investigated. The trends and change points were evaluated for different [...] Read more.
This study aimed to assess trends of hydro-meteorological variables in the Upper Omo-Ghibe river basin, Ethiopia. Data records from eleven rainfall, eight air temperature, and five streamflow stations between 1981 to 2008 were investigated. The trends and change points were evaluated for different periods of time depending on data availability. Mann-Kendall and Pettit tests were used to identify trends and change points at a 5% significance level. The tests were applied to mean annual, monthly and seasonal time scales. Rainfall exhibited statistically decreasing trends at a mean annual time scale, while seasonal rainfall depicted heterogeneous results in both directions. For the majority of the stations, air temperature showed statistically significant increasing trends. The magnitude of change in temperature for mean annual, wet and dry season has increased about 0.48, 0.46, and 0.61 °C per decade for Jimma station. The Pettit test revealed that the late 1980s and 1990s were the change points. There is generally a decreasing trend in streamflow. The decline in annual rainfall and rise in temperature affected the streamflow negatively. Overall, the results indicate that trend sand change point times varied considerably across the stations and catchments. The identified significant trends can help to support planning decisions for water management. Full article
(This article belongs to the Special Issue Hydroclimatic Variability at Local, Regional, and Global Scales)
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Open AccessEditorial
Environmental Flows Determination and Monitoring with Hydraulic Habitat Models—Pushing the Boundaries of Habitat Models Application
Water 2019, 11(9), 1950; https://doi.org/10.3390/w11091950 - 19 Sep 2019
Cited by 1 | Viewed by 702
Abstract
Hydraulic habitat simulation models were designed for the quantitative determination of environmental flows that consider the needs of aquatic fauna in rivers and streams. In the past 50 years, the modeling techniques were significantly developed, but expectations associated with model utility also increased. [...] Read more.
Hydraulic habitat simulation models were designed for the quantitative determination of environmental flows that consider the needs of aquatic fauna in rivers and streams. In the past 50 years, the modeling techniques were significantly developed, but expectations associated with model utility also increased. Nowadays, the tools are expected to be applicable across a range of spatial and temporal scales and to protect entire aquatic communities, while being inexpensive as well as easy to use in administrative and legal environments. Addressing these challenges is the focus of this volume. We invited papers that present recent developments in habitat modeling, supported by real life case studies. The submitted papers well represent the wide applicability of habitat simulation models, allowing us to address both ends of river management requirements: the ability to address very detailed site specific issues as well as the ability to address the coarse scale applications necessary in regional management. Full article
Open AccessArticle
Glacier Surface Mass Balance in the Suntar-Khayata Mountains, Northeastern Siberia
Water 2019, 11(9), 1949; https://doi.org/10.3390/w11091949 - 19 Sep 2019
Viewed by 843
Abstract
Arctic glaciers comprise a small fraction of the world’s land ice area, but their ongoing mass loss currently represents a large cryospheric contribution to the sea level rise. In the Suntar-Khayata Mountains (SKMs) of northeastern Siberia, in situ measurements of glacier surface mass [...] Read more.
Arctic glaciers comprise a small fraction of the world’s land ice area, but their ongoing mass loss currently represents a large cryospheric contribution to the sea level rise. In the Suntar-Khayata Mountains (SKMs) of northeastern Siberia, in situ measurements of glacier surface mass balance (SMB) are relatively sparse, limiting our understanding of the spatiotemporal patterns of regional mass loss. Here, we present SMB time series for all glaciers in the SKMs, estimated through a glacier SMB model. Our results yielded an average SMB of −0.22 m water equivalents (w.e.) year−1 for the whole region during 1951–2011. We found that 77.4% of these glaciers had a negative mass balance and detected slightly negative mass balance prior to 1991 and significantly rapid mass loss since 1991. The analysis suggests that the rapidly accelerating mass loss was dominated by increased surface melting, while the importance of refreezing in the SMB progressively decreased over time. Projections under two future climate scenarios confirmed the sustained rapid shrinkage of these glaciers. In response to temperature rise, the total present glacier area is likely to decrease by around 50% during the period 2071–2100 under representative concentration pathway 8.5 (RCP8.5). Full article
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Open AccessArticle
Analysis of Rainfall Trends and Extreme Precipitation in the Middle Adriatic Side, Marche Region (Central Italy)
Water 2019, 11(9), 1948; https://doi.org/10.3390/w11091948 - 19 Sep 2019
Cited by 5 | Viewed by 917
Abstract
Extreme precipitation trends and events are fundamental for the definition of the region’s climate and allow the subsequent analysis of the risk for the territory and the possible countermeasures. This study takes into account the Marche Region (Central Italy) with 128 rain gauges [...] Read more.
Extreme precipitation trends and events are fundamental for the definition of the region’s climate and allow the subsequent analysis of the risk for the territory and the possible countermeasures. This study takes into account the Marche Region (Central Italy) with 128 rain gauges from 1921 to 2017. Initially, in order to obtain a rainfall overview, the dominant trend of the period 1921–2017 was evaluated. Initially, in order to obtain a rainfall overview, the dominant trend of the period 1921–2017 was evaluated. In addition, to obtain a comparable analysis, the average precipitations grouped in climatological standard normals were analyzed. Finally, the main purpose of the research was achieved by analyzing extreme events in the middle Adriatic side. In addition, forecasts of extreme precipitation events, with a return period of 100 years, were made using the theory of “generalized extreme value” (GEV). The innovation of this research is represented by the use of geostatistics to spatialize the variables investigated, through a clear and immediate graphic representation performed through GIS software. This study is a necessary starting point for the study of climate dynamics in the region, and it is also a useful tool for land use planning. Full article
(This article belongs to the Section Water Resources Management, Policy and Governance)
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Open AccessArticle
Climate Change Made Major Contributions to Soil Water Storage Decline in the Southwestern US during 2003–2014
Water 2019, 11(9), 1947; https://doi.org/10.3390/w11091947 - 19 Sep 2019
Viewed by 589
Abstract
Soil water shortage is a critical issue for the Southwest US (SWUS), the typical arid region that has experienced severe droughts over the past decades, primarily caused by climate change. However, it is still not quantitatively understood how soil water storage in the [...] Read more.
Soil water shortage is a critical issue for the Southwest US (SWUS), the typical arid region that has experienced severe droughts over the past decades, primarily caused by climate change. However, it is still not quantitatively understood how soil water storage in the SWUS is affected by climate change. We integrated the time-series data of water storage and evapotranspiration derived from satellite data, societal water consumption, and meteorological data to quantify soil water storage changes and their climate change impacts across the SWUS from 2003 to 2014. The water storage decline was found across the entire SWUS, with a significant reduction in 98.5% of the study area during the study period. The largest water storage decline occurred in the southeastern portion, while only a slight decline occurred in the western and southwestern portions of the SWUS. Net atmospheric water input could explain 38% of the interannual variation of water storage variation. The climate-change-induced decreases in net atmospheric water input predominately controlled the water storage decline in 60% of the SWUS (primarily in Texas, Eastern New Mexico, Eastern Arizona, and Oklahoma) and made a partial contribution in approximately 17% of the region (Central and Western SWUS). Climate change, primarily as precipitation reduction, made major contributions to the soil water storage decline in the SWUS. This study infers that water resource management must consider the climate change impacts over time and across space in the SWUS. Full article
(This article belongs to the Section Water Use and Scarcity)
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Open AccessArticle
Assessing the Fresh–Saline Groundwater Distribution in the Nile Delta Aquifer Using a 3D Variable-Density Groundwater Flow Model
Water 2019, 11(9), 1946; https://doi.org/10.3390/w11091946 - 19 Sep 2019
Viewed by 698
Abstract
The Nile Delta Aquifer (NDA) is threatened by salt water intrusion (SWI). This article demonstrates an approach for identifying critical salinity concentration zones using a three-dimensional (3D) variable-density groundwater flow model in the NDA. An innovative procedure is presented for the delineation of [...] Read more.
The Nile Delta Aquifer (NDA) is threatened by salt water intrusion (SWI). This article demonstrates an approach for identifying critical salinity concentration zones using a three-dimensional (3D) variable-density groundwater flow model in the NDA. An innovative procedure is presented for the delineation of salinity concentration in 2010 by testing different simulation periods. The results confirm the presence of saline groundwater caused by SWI in the north of the NDA. In addition, certain regions in the east and southwest of the NDA show increased salinity concentration levels, possibly due to excessive groundwater extraction and dissolution of marine fractured limestone and shale that form the bedrock underlying the aquifer. The research shows that the NDA is still not in a state of dynamic equilibrium. The modeling instrument can be used for simulating future scenarios of SWI to provide a sustainable adaptation plan for groundwater resource. Full article
(This article belongs to the Special Issue Advances in the Field of Seawater Intrusion in Coastal Aquifers)
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Open AccessArticle
Reconstruction of Thermal Conditions in the Subboreal Inferred from Isotopic Studies of Groundwater and Calcareous Tufa from the Spring Mire Cupola in Wardzyń (Central Poland)
Water 2019, 11(9), 1945; https://doi.org/10.3390/w11091945 - 19 Sep 2019
Cited by 1 | Viewed by 606
Abstract
Studies with application of stable isotopes of oxygen and carbon have been performed on calcareous tufa, groundwater and dissolved inorganic carbon (DIC) from the spring mire cupola in Wardzyń. This study was focused on the verification of the a priori hypothesis that the [...] Read more.
Studies with application of stable isotopes of oxygen and carbon have been performed on calcareous tufa, groundwater and dissolved inorganic carbon (DIC) from the spring mire cupola in Wardzyń. This study was focused on the verification of the a priori hypothesis that the analysed calcareous tufa is a chemical deposit and on the attempt to supplement an earlier scenario of environmental changes in the Subboreal with oscillations of water temperature. The constructed model of chemical and isotope balance, and δ13C determinations in DIC, allowed for calculating ratios of stable isotopes of carbon in particular speciations and in gaseous CO2. The obtained results coupled with δ13C values in calcite indicate that this mineral precipitated from the solution chemically (without the contribution of living organisms). Additionally, it was possible to reconstruct the temperature range at which the calcareous tufa was formed. The reconstructed scenario of changes in the thermal conditions was refined based on δ18O determinations in groundwater and calcite. Accordingly, the oldest calcareous tufa, with an age of about 5500 cal years BP, was formed in cool climate conditions (with average annual temperatures by about 3 °C lower than presently). The formation of younger series of the calcareous tufa took place between 4400–2900 cal years BP and represents a much warmer period with two distinct cooler episodes at 3900 and 3000 cal years BP, respectively. The course of the obtained temperature curves correlates well with the GISP2 curve and curves obtained for other sites in Northern, and Central Europe. Full article
(This article belongs to the Section Hydrology and Hydrogeology)
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Open AccessArticle
Runoff Harvesting Site Suitability Analysis for Wildlife in Sub-Desert Regions
Water 2019, 11(9), 1944; https://doi.org/10.3390/w11091944 - 18 Sep 2019
Viewed by 772
Abstract
Site selection for runoff harvesting at large scales is a very complex task. It requires inclusion and spatial analysis of a multitude of accurately measured parameters in a time-efficient manner. Compared with direct measurements of runoff, which is time consuming and costly, a [...] Read more.
Site selection for runoff harvesting at large scales is a very complex task. It requires inclusion and spatial analysis of a multitude of accurately measured parameters in a time-efficient manner. Compared with direct measurements of runoff, which is time consuming and costly, a combination of a Geographic Information System (GIS) and multi-criteria techniques have proven feasible to address this challenge. Although the accuracy of this new approach is lower than the direct method, conducting in-situ measurements over large scales is not feasible due to its financial issues, a lack of sufficient human resources, and time limitations. To achieve this purpose, climatic, topographic, and soil parameters were used to estimate a runoff coefficient and volume for a single event with the 33%-exceedance probability of maximum daily rainfall in the Kavir National Park of Iran. The main challenges ahead of this research have been a) the large area of the park and the inability to directly evaluate site suitability for runoff harvesting, b) the need for a quick and reliable site evaluation to implement water harvesting measures to address water scarcity, and c) the lack of discharge volume data from water streams (as there are no permanent water streams in the site) and the necessity of reliably estimating runoff in different parts of the park to design water harvesting structures which have been addressed by using GIS and a rainfall-runoff model (Soil Conservation Service Curve Number (SCS-CN)). Site suitability was evaluated for the natural territory of two important wildlife species of the park, namely Gazella dorcas and Ovis orientalis, as the main important food sources of an endangered species named Acinonyx jubatus, commonly known as Persian Cheetah. Saving Persian Cheetah from extinction is currently the top priority for the park managers, which is the main factor behind the species chosen for this research. The Analytic Hierarchical Process (AHP) and fuzzy membership functions were employed to assign weights and standardized thematic layers, respectively. The layers were then integrated using the weighted linear combination method (WLC) to obtain the final suitability map. Accordingly, 38% of the area (846 km2) is suitable or highly suitable for runoff harvesting, while 62% (2623 km2) has a very low potential for this purpose. Afterward, 11 suitable locations were identified to collect runoff. The results indicated that suitable catchments are mainly located on the southern slopes of the Mount Siahkouh as the only major elevation in the area. The storage capacity of the earth embankment in each catchment was estimated based on the upstream area of the catchment and runoff volume. Based on the population of the intended wildlife species and their average water requirement, there is a need for 6500 m3 of drinking water annually. In the best-case scenario and under the circumstance of receiving five rainstorm events a year, only 257 m3 is collectible from all runoff harvesting structures, which is only 4% of the total water demand. Full article
(This article belongs to the Section Water Use and Scarcity)
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Open AccessArticle
Sites and Indicators of MAR as a Successful Tool to Mitigate Climate Change Effects in Spain
Water 2019, 11(9), 1943; https://doi.org/10.3390/w11091943 - 18 Sep 2019
Cited by 3 | Viewed by 1136
Abstract
In this article, the authors will support Managed Aquifer Recharge (MAR) as a tool to combat Climate Change (CC) adverse impacts on the basis of real sites, indicators, and specific cases located Spain. MAR has been used in Spain in combination with other [...] Read more.
In this article, the authors will support Managed Aquifer Recharge (MAR) as a tool to combat Climate Change (CC) adverse impacts on the basis of real sites, indicators, and specific cases located Spain. MAR has been used in Spain in combination with other measures of Integrated Water Resources Management (IWRM) to mitigate and adapt to Climate Change (CC) challenges. The main effects of CC are that the rising of the average atmospheric temperature together with the decreasing average annual precipitation rate cause extreme weather and induce sea level rise. These pattern results in a series of negative impacts reflected in an increase of certain events or parameters, such as evaporation, evapotranspiration, water demand, fire risk, run-off, floods, droughts, and saltwater intrusion; and a decrease of others such as availability of water resources, the wetland area, and the hydro-electrical power production. Solutions include underground storage, lowering the temperature, increasing soil humidity, reclaimed water infiltration, punctual and directed infiltration, self-purification and naturalization, off-river storage, wetland restoration and/or establishment, flow water distribution by gravity, power saving, eventual recharge of extreme flows, multi-annual management and positive barrier wells against saline water intrusion. The main advantages and disadvantages for each MAR solution have been addressed. As success must be measured, some indicators have been designed or adopted and calculated to quantify the actual effect of these solutions and their evolution. They have been expressed in the form of volumes, lengths, areas, percentages, grades, euros, CO2 emissions, and years. Therefore, MAR in Spain demonstrably supports its usefulness in battling CC adverse impacts in a broad variety of environments and circumstances. This situation is comparable to other countries where MAR improvements have also been assessed. Full article
(This article belongs to the Special Issue Managed Aquifer Recharge for Water Resilience)
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Open AccessArticle
Evaluating Evaporation Methods for Estimating Small Reservoir Water Surface Evaporation in the Brazilian Savannah
Water 2019, 11(9), 1942; https://doi.org/10.3390/w11091942 - 18 Sep 2019
Cited by 2 | Viewed by 821
Abstract
Small reservoirs play a key role in the Brazilian savannah (Cerrado), making irrigation feasible and contributing to the economic development and social well-being of the population. A lack of information on factors, such as evaporative water loss, has an impact on the design [...] Read more.
Small reservoirs play a key role in the Brazilian savannah (Cerrado), making irrigation feasible and contributing to the economic development and social well-being of the population. A lack of information on factors, such as evaporative water loss, has an impact on the design and management of these reservoirs, as well as on regional water safety. Acquiring this information is crucial for hydrologists to develop more effective water resource management strategies and policies. This study assesses the performance of a diverse number of methods that are used to estimate evaporation and provides evaporation probability curves on a fortnightly period for small reservoirs in the Brazilian savannah region. Evaporation data were collected for a small water reservoir located in the Buriti Vermelho watershed, a typical dam of the Brazilian savannah region. Among the assessed methods, those of Kohler et al. (1955) and Linacre (1993) presented the best performances on both the daily and monthly scales for evaporation estimates. By simulating the evaporation rates for a timeseries, an increasing trend in evaporation was observed for the transition between the dry and wet seasons, jeopardizing double cropping in the region. The developed probability curves are an important tool for improving water resource planning and increasing the local water availability. Full article
(This article belongs to the Section Water Use and Scarcity)
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Open AccessArticle
Seasonal and Scale Effects of Anthropogenic Pressures on Water Quality and Ecological Integrity: A Study in the Sabor River Basin (NE Portugal) Using Partial Least Squares-Path Modeling
Water 2019, 11(9), 1941; https://doi.org/10.3390/w11091941 - 18 Sep 2019
Cited by 2 | Viewed by 911
Abstract
Interactions between pollution sources, water contamination, and ecological integrity are complex phenomena and hard to access. To comprehend this subject of study, it is crucial to use advanced statistical tools, which can unveil cause-effect relationships between pressure from surface waters, released contaminants, and [...] Read more.
Interactions between pollution sources, water contamination, and ecological integrity are complex phenomena and hard to access. To comprehend this subject of study, it is crucial to use advanced statistical tools, which can unveil cause-effect relationships between pressure from surface waters, released contaminants, and damage to the ecological status. In this study, two partial least squares-path models (PLS-PM) were created and analyzed in order to understand how the cause-effect relationships can change over two seasons (summer and winter) and how the used scale (short or long) can affect the results. During the summer of 2016 and winter of 2017 surface water parameters and the North Invertebrate Portuguese Index were measured in strategic sampling sites. For each site, it two sections were delineated: the total upstream drainage area (long scale) and 250 m (short scale). For each section, data of pressures in surface waters including point source, diffuse emissions and landscape metrics were gathered. The methodology was applied to the Sabor River Basin, located in the northeast of Portugal. In this study, it was possible to determine in which season pressures affect ecological integrity and also which scale should be addressed. The models showed the influences of manganese and of potassium concentrations in stream water on the decrease in summer water quality, while arsenic’s harmful effect occurs during winter. Pastures and environmental land use conflicts were considered threats to water quality when analyzed on a long scale, whereas agricultural areas played a role when the short scale was used. The effect of landscape edge density revealed to be independent of scale or season. Effluent discharges in surface water affected the water quality during the summer season, while the effect of discharges in groundwater affected the water quality in winter. It has also been found that, to find the harmful effect of pressures, it is necessary to approach different scales and that the role of landscape metrics can also overlap contaminant sources. Full article
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Open AccessArticle
Machine Learning Approaches to Develop Pedotransfer Functions for Tropical Sri Lankan Soils
Water 2019, 11(9), 1940; https://doi.org/10.3390/w11091940 - 18 Sep 2019
Cited by 3 | Viewed by 712
Abstract
Poor data availability on soil hydraulic properties in tropical regions hampers many studies, including crop and environmental modeling. The high cost and effort of measurement and the increasing demand for such data have driven researchers to search for alternative approaches. Pedotransfer functions (PTFs) [...] Read more.
Poor data availability on soil hydraulic properties in tropical regions hampers many studies, including crop and environmental modeling. The high cost and effort of measurement and the increasing demand for such data have driven researchers to search for alternative approaches. Pedotransfer functions (PTFs) are predictive functions used to estimate soil properties by easily measurable soil parameters. PTFs are popular in temperate regions, but few attempts have been made to develop PTFs in tropical regions. Regression approaches are widely used to develop PTFs worldwide, and recently a few attempts were made using machine learning methods. PTFs for tropical Sri Lankan soils have already been developed using classical multiple linear regression approaches. However, no attempts were made to use machine learning approaches. This study aimed to determine the applicability of machine learning algorithms in developing PTFs for tropical Sri Lankan soils. We tested three machine learning algorithms (artificial neural networks (ANN), k-nearest neighbor (KNN), and random forest (RF)) with three different input combination (sand, silt, and clay (SSC) percentages; SSC and bulk density (BD); SSC, BD, and organic carbon (OC)) to estimate volumetric water content (VWC) at −10 kPa, −33 kPa (representing field capacity (FC); however, most studies in Sri Lanka use −33 kPa as the FC) and −1500 kPa (representing the permanent wilting point (PWP)) of Sri Lankan soils. This analysis used the open-source data mining software in the Waikato Environment for Knowledge Analysis. Using a wrapper approach and best-first search method, we selected the most appropriate inputs to develop PTFs using different machine learning algorithms and input levels. We developed PTFs to estimate FC and PWP and compared them with the previously reported PTFs for tropical Sri Lankan soils. We found that RF was the best algorithm to develop PTFs for tropical Sri Lankan soils. We tried to further the development of PTFs by adding volumetric water content at −10 kPa as an input variable because it is quite an easily measurable parameter compared to the other targeted VWCs. With the addition of VWC at −10 kPa, all machine learning algorithms boosted the performance. However, RF was the best. We studied the functionality of finetuned PTFs and found that they can estimate the available water content of Sri Lankan soils as well as measurements-based calculations. We identified RF as a robust alternative to linear regression methods in developing PTFs to estimate field capacity and the permanent wilting point of tropical Sri Lankan soils. With those findings, we recommended that PTFs be developed using the RF algorithm in the related software to make up for the data gaps present in tropical regions. Full article
(This article belongs to the Section Water, Agriculture and Aquaculture)
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Open AccessCase Report
Emergency Disposal Solution for Control of a Giant Landslide and Dammed Lake in Yangtze River, China
Water 2019, 11(9), 1939; https://doi.org/10.3390/w11091939 - 18 Sep 2019
Cited by 1 | Viewed by 788
Abstract
Although landslide early warning and post-assessment is of great interest for mitigating hazards, emergency disposal solutions for properly handling the landslide and dammed lake within a few hours or days to mitigate flood risk are fundamentally challenging. In this study, we report a [...] Read more.
Although landslide early warning and post-assessment is of great interest for mitigating hazards, emergency disposal solutions for properly handling the landslide and dammed lake within a few hours or days to mitigate flood risk are fundamentally challenging. In this study, we report a general strategy to effectively tackle the dangerous situation created by a giant dammed lake with 770 million cubic meters of water volume and formulate an emergency disposal solution for the 25 million cubic meters of debris, composed of engineering measures of floodgate excavation and non-engineering measures of reservoirs/hydropower stations operation. Such a disposal solution can not only reduce a large-scale flood (10,000-year return period, 0.01%) into a small-scale flood (10-year return period, 10%) but minimize the flood risk as well, guaranteeing no death raised by the giant landslide. Full article
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Open AccessArticle
Flood Monitoring in Vegetated Areas Using Multitemporal Sentinel-1 Data: Impact of Time Series Features
Water 2019, 11(9), 1938; https://doi.org/10.3390/w11091938 - 18 Sep 2019
Cited by 5 | Viewed by 858
Abstract
Synthetic Aperture Radar (SAR) is particularly suitable for large-scale mapping of inundations, as this tool allows data acquisition regardless of illumination and weather conditions. Precise information about the flood extent is an essential foundation for local relief workers, decision-makers from crisis management authorities [...] Read more.
Synthetic Aperture Radar (SAR) is particularly suitable for large-scale mapping of inundations, as this tool allows data acquisition regardless of illumination and weather conditions. Precise information about the flood extent is an essential foundation for local relief workers, decision-makers from crisis management authorities or insurance companies. In order to capture the full extent of the flood, open water and especially temporary flooded vegetation (TFV) areas have to be considered. The Sentinel-1 (S-1) satellite constellation enables the continuous monitoring of the earths surface with a short revisit time. In particular, the ability of S-1 data to penetrate the vegetation provides information about water areas underneath the vegetation. Different TFV types, such as high grassland/reed and forested areas, from independent study areas were analyzed to show both the potential and limitations of a developed SAR time series classification approach using S-1 data. In particular, the time series feature that would be most suitable for the extraction of the TFV for all study areas was investigated in order to demonstrate the potential of the time series approaches for transferability and thus for operational use. It is shown that the result is strongly influenced by the TFV type and by other environmental conditions. A quantitative evaluation of the generated inundation maps for the individual study areas is carried out by optical imagery. It shows that analyzed study areas have obtained Producer’s/User’s accuracy values for TFV between 28% and 90%/77% and 97% for pixel-based classification and between 6% and 91%/74% and 92% for object-based classification depending on the time series feature used. The analysis of the transferability for the time series approach showed that the time series feature based on VV (vertical/vertical) polarization is particularly suitable for deriving TFV types for different study areas and based on pixel elements is recommended for operational use. Full article
(This article belongs to the Special Issue Improving Flood Detection and Monitoring through Remote Sensing)
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Open AccessEditorial
Soil and Water Conservation in Agricultural and Forestry Systems
Water 2019, 11(9), 1937; https://doi.org/10.3390/w11091937 - 17 Sep 2019
Cited by 3 | Viewed by 922
Abstract
This special issue includes six articles that cover a variety of issues about the topic of soil and water conservation in agricultural systems, including the following: a bibliometric analysis of soil and water conservation in the Loess Region of China; regarding croplands, one [...] Read more.
This special issue includes six articles that cover a variety of issues about the topic of soil and water conservation in agricultural systems, including the following: a bibliometric analysis of soil and water conservation in the Loess Region of China; regarding croplands, one study evaluated the influence of vegetation covers on topsoil moisture and the effect of physiographic conditions on sediment yield in Spanish vineyards; another study evaluated the influence of plant age on soil water depletion in alfalfa pastures in the Tibet Autonomous Region; in a Chinese forest plantation, the effect of plant age and species on soil bulk density and pH was evaluated, and the most suitable afforestation species and stand age recommended to harvest maximum benefits were determined; regarding water pollution, a study evaluated soil water dynamics during two fallow years and three barley crop seasons in Spain and estimated the effect of the applied fertilizer (slurries or minerals) on nitrate leaching; and finally, another study identified the key information, including heavy metals, for water conservation in the border areas of the Syr Darya River in Kazakhstan. The proper use of soil and water resources is necessary to ensure the future well-being of humans and of the environment. Full article
(This article belongs to the Special Issue Soil and Water Conservation in Agricultural and Forestry Systems)
Open AccessCorrection
Correction: Hu, Q., et al. Rainfall Spatial Estimations: A Review from Spatial Interpolation to Multi-Source Data Merging. Water 2019, 11, 579
Water 2019, 11(9), 1936; https://doi.org/10.3390/w11091936 - 17 Sep 2019
Viewed by 580
Abstract
The authors wish to make the following corrections to this paper [...] Full article
(This article belongs to the Section Hydrology and Hydrogeology)
Open AccessArticle
Removal of >10 µm Microplastic Particles from Treated Wastewater by a Disc Filter
Water 2019, 11(9), 1935; https://doi.org/10.3390/w11091935 - 17 Sep 2019
Cited by 4 | Viewed by 1164
Abstract
In this paper, we evaluate the performance of a disc filter that retains microplastic (MP) particles from treated wastewater. A focal plane array-based Fourier transform infrared imaging technique enabled MP quantification and an in-house-built software (MPhunter) facilitated automatic analysis of the obtained infrared [...] Read more.
In this paper, we evaluate the performance of a disc filter that retains microplastic (MP) particles from treated wastewater. A focal plane array-based Fourier transform infrared imaging technique enabled MP quantification and an in-house-built software (MPhunter) facilitated automatic analysis of the obtained infrared spectra. The disc filter retained 89.7% of particles, and 75.6% of their mass. This removal efficiency is comparable to removal rates reported by previous studies. However, the presence of an unexpectedly large number of MP particles whose size substantially exceeded the pore size of the disc filter suggests that particles could either bypass or pass through the filter mesh, somewhat diminishing the performance of the filter. The concentration of MPs in the effluent was 3 MP/L, corresponding to an estimated mass concentration of 0.31 µg/L. The annual MP discharge from the studied WWTP after the disc filter was estimated to be 1.1 kg in 2017. It was hence not a significant contributor to MP emissions in Denmark. Although the operation of the disc filter seems to have been disturbed, it nonetheless achieved a high MP removal rate. Therefore, we conclude that it is a suitable technology to decrease the concentration of discharged MPs in wastewater effluents. Full article
(This article belongs to the Section Wastewater Treatment and Reuse)
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Open AccessArticle
Support Vector Regression Integrated with Fruit Fly Optimization Algorithm for River Flow Forecasting in Lake Urmia Basin
Water 2019, 11(9), 1934; https://doi.org/10.3390/w11091934 - 17 Sep 2019
Cited by 10 | Viewed by 811
Abstract
Advancement in river flow prediction systems can greatly empower the operational river management to make better decisions, practices, and policies. Machine learning methods recently have shown promising results in building accurate models for river flow prediction. This paper aims to identify models with [...] Read more.
Advancement in river flow prediction systems can greatly empower the operational river management to make better decisions, practices, and policies. Machine learning methods recently have shown promising results in building accurate models for river flow prediction. This paper aims to identify models with higher accuracy, robustness, and generalization ability by inspecting the accuracy of a number of machine learning models. The proposed models for river flow include support vector regression (SVR), a hybrid of SVR with a fruit fly optimization algorithm (FOA) (so-called FOASVR), and an M5 model tree (M5). Additionally, the influence of periodicity (π) on the forecasting enactment was examined. To assess the performance of the proposed models, different statistical meters were implemented, including root mean squared error (RMSE), mean absolute error (MAE), correlation coefficient (R), and Bayesian information criterion (BIC). Results showed that the FOASVR with RMSE (4.36 and 6.33 m3/s), MAE (2.40 and 3.71 m3/s) and R (0.82 and 0.81) values had the best performance in forecasting river flows at Babarud and Vaniar stations, respectively. Also, regarding BIC parameters, Qt−1 and π were selected as parsimonious inputs for predicting river flow one month ahead. Overall findings indicated that, although both the FOASVR and M5 predicted the river flows in suitable accordance with observed river flows, the performance of the FOASVR was moderately better than the M5 and periodicity noticeably increased the performance of the models; consequently, FOASVR can be suggested as the most accurate method for forecasting river flows. Full article
(This article belongs to the Section Hydrology and Hydrogeology)
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Open AccessArticle
Groundwater Autochthonous Microbial Communities as Tracers of Anthropogenic Pressure Impacts: Example from a Municipal Waste Treatment Plant (Latium, Italy)
Water 2019, 11(9), 1933; https://doi.org/10.3390/w11091933 - 16 Sep 2019
Viewed by 741
Abstract
The groundwater behavior at a municipal solid waste disposal dump, located in Central Italy, was studied using a multi-parameter monitoring over 1 year consisting of 4 seasonal samples. The hydrological and hydrogeological dynamics of water circulation, microbiological parameters (microbial abundance and cell viability [...] Read more.
The groundwater behavior at a municipal solid waste disposal dump, located in Central Italy, was studied using a multi-parameter monitoring over 1 year consisting of 4 seasonal samples. The hydrological and hydrogeological dynamics of water circulation, microbiological parameters (microbial abundance and cell viability of the autochthonous microbial community), dissolved organic carbon, and several contaminants were evaluated and related to the geological structures in both two and three dimensions and used for geostatistical analysis in order to obtain 3D maps. Close relationships between geological heterogeneity, water circulation, pollutant diffusion, dissolved organic carbon, and cell viability were revealed. The highest cell viability values were found with dissolved organic carbon (DOC) values ≤0.5 mg/L; above this value, DOC negatively affected the microbial community. The highest DOC values were detected in groundwater at some sampling points within the site indicating its probable origin from the waste disposal dump. Although legislation limits for the parameters measured were not exceeded (except for a contaminant in one piezometer), the 1-year multi-parameter monitoring approach made it possible to depict both the dynamics and the complexity of the groundwater flux and, with “non-legislative parameters” such as microbial cell viability and DOC, identify the points with the highest vulnerability and their origin. This approach is useful for identifying the most vulnerable sites in a groundwater body. Full article
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Open AccessArticle
Improving Flows in Misaligned Culverts
Water 2019, 11(9), 1932; https://doi.org/10.3390/w11091932 - 16 Sep 2019
Viewed by 779
Abstract
This study investigated different approaches to optimize flows in misaligned culverts. Structures aligned with the natural stream are always preferred, as misalignments cause a change of direction at the culvert inlet associated with lower performance and sedimentation and erosion problems. This optimal positioning [...] Read more.
This study investigated different approaches to optimize flows in misaligned culverts. Structures aligned with the natural stream are always preferred, as misalignments cause a change of direction at the culvert inlet associated with lower performance and sedimentation and erosion problems. This optimal positioning can cause high financial costs and a flow optimization minimizing the associated problems could be a viable alternative. In this study, we used computational fluid dynamics analysis to evaluate the flow in 44 different scenarios with misalignment angles ranging from 0 ° to 90 ° . It was found that smooth transitions towards the narrowest point in the stream (culvert) were possible for any degree of misalignment resulting in improved, uniform velocity distributions and less turbulence. An experimental setup was able to confirm the possible flow improvements. The proposed approach of flow redirection can lower construction costs and gives planners and designers more flexibility as tailored reinforcement and redesign of the stream embankment can be used as an alternative to costly creek alignments. Full article
(This article belongs to the Section Hydraulics and Hydrodynamics)
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Open AccessArticle
The Effect of Chironomid Larvae on Nitrogen Cycling and Microbial Communities in Soft Sediments
Water 2019, 11(9), 1931; https://doi.org/10.3390/w11091931 - 16 Sep 2019
Cited by 2 | Viewed by 1087
Abstract
The combination of biogeochemical methods and molecular techniques has the potential to uncover the black-box of the nitrogen (N) cycle in bioturbated sediments. Advanced biogeochemical methods allow the quantification of the process rates of different microbial processes, whereas molecular tools allow the analysis [...] Read more.
The combination of biogeochemical methods and molecular techniques has the potential to uncover the black-box of the nitrogen (N) cycle in bioturbated sediments. Advanced biogeochemical methods allow the quantification of the process rates of different microbial processes, whereas molecular tools allow the analysis of microbial diversity (16S rRNA metabarcoding) and activity (marker genes and transcripts) in biogeochemical hot-spots such as the burrow wall or macrofauna guts. By combining biogeochemical and molecular techniques, we analyzed the role of tube-dwelling Chironomus plumosus (Insecta, Diptera) larvae on nitrification and nitrate reduction processes in a laboratory experiment with reconstructed sediments. We hypothesized that chironomid larvae stimulate these processes and host bacteria actively involved in N-cycling. Our results suggest that chironomid larvae significantly enhance the recycling of ammonium (80.5 ± 48.7 µmol m−2 h−1) and the production of dinitrogen (420.2 ± 21.4 µmol m−2 h−1) via coupled nitrification–denitrification and the consumption of water column nitrates. Besides creating oxygen microniches in ammonium-rich subsurface sediments via burrow digging and ventilation, chironomid larvae serve as hot-spots of microbial communities involved in N-cycling. The quantification of functional genes showed a significantly higher potential for microbial denitrification and nitrate ammonification in larvae as compared to surrounding sediments. Future studies may further scrutinize N transformation rates associated with intimate macrofaunal–bacteria associations. Full article
(This article belongs to the Special Issue The Role of Macrobiota in Aquatic Nutrient Cycling)
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Open AccessArticle
The Influence of Riparian Corridor Land Use on the Pesquería River’s Macroinvertebrate Community (N.E. Mexico)
Water 2019, 11(9), 1930; https://doi.org/10.3390/w11091930 - 16 Sep 2019
Viewed by 1111
Abstract
The Earth’s freshwater ecosystems are currently under threat, particularly in developing countries. In Mexico, intensive land use and inadequate monitoring policies have resulted in the severe degradation of the country’s freshwater ecosystems. This study assesses how the macroinvertebrate communities in the Pesquería River, [...] Read more.
The Earth’s freshwater ecosystems are currently under threat, particularly in developing countries. In Mexico, intensive land use and inadequate monitoring policies have resulted in the severe degradation of the country’s freshwater ecosystems. This study assesses how the macroinvertebrate communities in the Pesquería River, located in Northeastern Mexico, are affected by riparian land use, in order to determine their potential use as bioindicators to evaluate the macroinvertebrate integrity of the Pesquería River. First, we characterized the land use cover in the riparian channel. Second, we sampled 16 sites for benthic macroinvertebrates along the main channel during the wet and dry seasons. Third, we evaluated the influence of the riparian channel land use on the macroinvertebrate community using 42 different biological metrics. The land use characterization depicted a riparian channel mainly influenced by agricultural and urban land use. Eighty-one invertebrate taxa were identified during the study. Permutational analysis of the variance analysis confirmed significant differences across the different land use classes and the macroinvertebrate community composition while no differences were found between seasons. The indicator species analysis revealed 31 representative taxa for natural land use, 1 for urban, and 4 for agricultural land use. Our modelling analysis showed that 28 of the 42 biological metrics tested responded significantly to land use disturbances, confirming the impact of land use changes on the Pesquería River’s macroinvertebrate communities and suggesting that these metrics may have a use as bioindicators. Finally, this study may provide significant biological information for further studies in similar conditions. Full article
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Open AccessArticle
Acetaminophen Removal from Water by Microalgae and Effluent Toxicity Assessment by the Zebrafish Embryo Bioassay
Water 2019, 11(9), 1929; https://doi.org/10.3390/w11091929 - 15 Sep 2019
Cited by 2 | Viewed by 1258
Abstract
In this work, zebrafish embryo bioassays were performed to assess the efficiency of microalgae in the removal of acetaminophen from water. Chlorella sorokiniana (CS), Chlorella vulgaris (CV) and Scenedesmus obliquus (SO) were the strains used for water treatment. Toxic effects on zebrafish embryo [...] Read more.
In this work, zebrafish embryo bioassays were performed to assess the efficiency of microalgae in the removal of acetaminophen from water. Chlorella sorokiniana (CS), Chlorella vulgaris (CV) and Scenedesmus obliquus (SO) were the strains used for water treatment. Toxic effects on zebrafish embryo caused by effluents from microalgae treatment were compared with those observed under exposure to experimental solutions with known concentrations of acetaminophen. The three microalgae strains allowed for the reduction of acetaminophen concentration and its toxic effects, but CS was the most efficient one. At the end of the batch culture, a 67% removal was provided by CS with a reduction of 62% in the total abnormalities on the exposed zebrafish embryo. On the other hand, toxic effects observed under exposure to effluents treated by microalgae were alike to those determined for acetaminophen experimental solutions with equivalent concentration. Thus, it may be inferred that microalgae biodegradation of acetaminophen did not involve an increased toxicity for zebrafish embryo. Full article
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Open AccessArticle
A Numerical Study of Fluid Flow in a Vertical Slot Fishway with the Smoothed Particle Hydrodynamics Method
Water 2019, 11(9), 1928; https://doi.org/10.3390/w11091928 - 15 Sep 2019
Cited by 1 | Viewed by 826
Abstract
Fishways have a great ecological importance as they help mitigate the interruptions of fish migration routes. In the present work, the novel DualSPHysics v4.4 solver, based on the smoothed particle hydrodynamics method (SPH), has been applied to perform three-dimensional (3-D) simulations of water [...] Read more.
Fishways have a great ecological importance as they help mitigate the interruptions of fish migration routes. In the present work, the novel DualSPHysics v4.4 solver, based on the smoothed particle hydrodynamics method (SPH), has been applied to perform three-dimensional (3-D) simulations of water flow in a vertical slot fishway (VSF). The model has been successfully calibrated against published field data of flow velocities that were measured with acoustic Doppler velocity probes. A state-of-the-art algorithm for the treatment of open boundary conditions using buffer layers has been applied to accurately reproduce discharges, water elevations, and average velocity profiles (longitudinal and transverse velocities) within the observed pool of the VSF. Results herein indicate that DualSPHysics can be an accurate tool for modeling turbulent subcritical free surface flows similar to those that occur in VSF. A novel relation between the number of fluid particles and the artificial viscosity coefficient has been formulated with a simple logarithmic fit. Full article
(This article belongs to the Section Hydraulics and Hydrodynamics)
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Open AccessArticle
Investigation of Karst Spring Flow Cessation Using Grey System Models
Water 2019, 11(9), 1927; https://doi.org/10.3390/w11091927 - 15 Sep 2019
Viewed by 718
Abstract
Karst aquifers are prominent sources of water worldwide; they store large amounts of water and are known for their beautiful springs. However, extensive groundwater development and climate variation has resulted in a decline in the flow of most karst springs; some have even [...] Read more.
Karst aquifers are prominent sources of water worldwide; they store large amounts of water and are known for their beautiful springs. However, extensive groundwater development and climate variation has resulted in a decline in the flow of most karst springs; some have even dried up. In order to obtain a better understanding of the factors contributing to this development, this study introduced grey system models, which quantified spring flow, taking Jinci Springs (China), which dried up in May 1994, as an example. Based on the characteristics of Jinci Springs, spring flow was divided into two stages: first (1954–1960), when the spring flow was affected only by climate variation; and second (1961–1994), when the flow was impacted by both climate variation and anthropogenic activities. The results showed that Jinci Springs flow had a strong relationship with precipitation occurring one year and three years earlier in the first stage. Subsequently, a grey system GM (1,3) model with one-year and three-year lags was set up for the first stage. By using the GM (1,3) model, we simulated the spring flow in the second stage under effects of climate variation only. By subtracting the observed spring flow from the simulated flow, we obtained the contribution of anthropogenic activities to Jinci Springs’ cessation. The contribution of anthropogenic activities and climate variation to the decline was 1.46 m3/s and 0.62 m3/s, respectively. Finally, each human activity that caused the decline was estimated. The methods devised herein can be used to describe karst hydrological processes that are under the effects of anthropogenic activities and climate variation. Full article
(This article belongs to the Section Hydrology and Hydrogeology)
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Open AccessArticle
Water Infrastructure Always In-The-Making: Distributing Water and Authority through the Water Supply Network in Moamba, Mozambique
Water 2019, 11(9), 1926; https://doi.org/10.3390/w11091926 - 15 Sep 2019
Cited by 3 | Viewed by 1391
Abstract
Using the concept of sociotechnical tinkering, this paper provides detailed empirical observations about the everyday practices of design, construction, operation, maintenance and use of a piped water supply network in a small town in Mozambique. We use these to show that the form, [...] Read more.
Using the concept of sociotechnical tinkering, this paper provides detailed empirical observations about the everyday practices of design, construction, operation, maintenance and use of a piped water supply network in a small town in Mozambique. We use these to show that the form, materiality, and functioning of this water infrastructure are constantly changing as result of interactions with its physical environment as well as in response to experimentation and improvisation by engineers, construction workers, operators and water users. Sociotechnical tinkering not just (re)distributes water, but also provides an avenue through which powers to control water flows can be wielded and exercised. In this sense, empirical attention to sociotechnical tinkering provides a useful entry-point for rethinking the distribution of control, authority and responsibility in water governance, or more broadly the relations between power and infrastructure. This, in turn, may yield new inspirations for identifying pragmatic possibilities for progressive water politics. Full article
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