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Editor’s Choice Articles

Editor’s Choice articles are based on recommendations by the scientific editors of MDPI journals from around the world. Editors select a small number of articles recently published in the journal that they believe will be particularly interesting to readers, or important in the respective research area. The aim is to provide a snapshot of some of the most exciting work published in the various research areas of the journal.

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Article

25 pages, 5002 KiB  
Article
Economic and Sustainability Inequalities and Water Consumption of European Union Countries
by Marcos Ferasso, Lydia Bares, Daniel Ogachi and Miguel Blanco
Water 2021, 13(19), 2696; https://doi.org/10.3390/w13192696 - 29 Sep 2021
Cited by 13 | Viewed by 6263
Abstract
Water scarcity is becoming a global concern for many reasons as its consumption increases. This research aimed to analyze sustainability inequalities in the water consumption of EU countries. Descriptive statistics using data for four AQUASTAT periods (2002, 2007, 2012, and 2017), and quotients [...] Read more.
Water scarcity is becoming a global concern for many reasons as its consumption increases. This research aimed to analyze sustainability inequalities in the water consumption of EU countries. Descriptive statistics using data for four AQUASTAT periods (2002, 2007, 2012, and 2017), and quotients for the AQUASTAT 2017 period, were calculated using a proposed econometric model. The main results were that countries with high GPD and population showed high water stress and total water withdrawal. Countries with lower industry-value-added-to-GDP quotients were among those with higher industrial water use efficiency, while low water-services-use-efficiency quotients were associated with high services value added to GDP. Suggestions for policymakers are provided and formula application guidelines for regional-level comparisons are described. Full article
(This article belongs to the Section Water Resources Management, Policy and Governance)
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17 pages, 4164 KiB  
Article
Temporal Influences of Vegetation Cover (C) Dynamism on MUSLE Sediment Yield Estimates: NDVI Evaluation
by David Gwapedza, Denis Arthur Hughes, Andrew Robert Slaughter and Sukhmani Kaur Mantel
Water 2021, 13(19), 2707; https://doi.org/10.3390/w13192707 - 29 Sep 2021
Cited by 9 | Viewed by 5924
Abstract
Vegetation cover is an important factor controlling erosion and sediment yield. Therefore, its effect is accounted for in both experimental and modelling studies of erosion and sediment yield. Numerous studies have been conducted to account for the effects of vegetation cover on erosion [...] Read more.
Vegetation cover is an important factor controlling erosion and sediment yield. Therefore, its effect is accounted for in both experimental and modelling studies of erosion and sediment yield. Numerous studies have been conducted to account for the effects of vegetation cover on erosion across spatial scales; however, little has been conducted across temporal scales. This study investigates changes in vegetation cover across multiple temporal scales in Eastern Cape, South Africa and how this affects erosion and sediment yield modelling in the Tsitsa River catchment. Earth observation analysis and sediment yield modelling are integrated within this study. Landsat 8 imagery was processed, and Normalised Difference Vegetation Index (NDVI) values were extracted and applied to parameterise the Modified Universal Soil Loss Equation (MUSLE) vegetation (C) factor. Imagery data from 2013–2018 were analysed for an inter-annual trend based on reference summer (March) images, while monthly imagery for the years 2016–2017 was analysed for intra-annual trends. The results indicate that the C exhibits more variation across the monthly timescale than the yearly timescale. Therefore, using a single month to represent the annual C factor increases uncertainty. The modelling shows that accounting for temporal variations in vegetation cover reduces cumulative simulated sediment by up to 85% across the inter-annual and 30% for the intra-annual scale. Validation with observed data confirmed that accounting for temporal variations brought cumulative sediment outputs closer to observations. Over-simulations are high in late autumn and early summer, when estimated C values are high. Accordingly, uncertainties are high in winter when low NDVI leads to high C, whereas dry organic matter provides some protection from erosion. The results of this study highlight the need to account for temporal variations in vegetation cover in sediment yield estimation but indicate the uncertainties associated with using NDVI to estimate C factor. Full article
(This article belongs to the Special Issue Modelling of Soil Conservation, Soil Erosion and Sediment Transport)
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19 pages, 7750 KiB  
Article
Modelling the Influence from Biota and Organic Matter on the Transport Dynamics of Microplastics in the Water Column and Bottom Sediments in the Oslo Fjord
by Anfisa Berezina, Evgeniy Yakushev, Oleg Savchuk, Christian Vogelsang and André Staalstrom
Water 2021, 13(19), 2690; https://doi.org/10.3390/w13192690 - 28 Sep 2021
Cited by 14 | Viewed by 3337
Abstract
The fate of microplastics (MP) in seawater is heavily influenced by the biota: the density of MP particles can be changed due to biofouling, which affects sinking, or MP can be digested by zooplankton and transferred into fecal pellets with increased sinking rate. [...] Read more.
The fate of microplastics (MP) in seawater is heavily influenced by the biota: the density of MP particles can be changed due to biofouling, which affects sinking, or MP can be digested by zooplankton and transferred into fecal pellets with increased sinking rate. We hypothesize that seasonal production and degradation of organic matter, and corresponding changes in the plankton ecosystem affect the MP capacity for transportation and burying in sediments in different seasons. This is simulated with a coupled hydrodynamical-biogeochemical model that provides a baseline scenario of the seasonal changes in the planktonic ecosystem and changes in the availability of particulate and dissolved organic matter. In this work, we use a biogeochemical model OxyDep that simulates seasonal changes of phytoplankton (PHY), zooplankton (HET), dissolved organic matter (DOM) and detritus (POM). A specifically designed MP module considers MP particles as free particles (MPfree), particles with biofouling (MPbiof), particles consumed by zooplankton (MPhet) and particles in detritus, including fecal pellets (MPdet). A 2D coupled benthic-pelagic vertical transport model 2DBP was applied to study the effect of seasonality on lateral transport of MP and its burying in the sediments. OxyDep and MP modules were coupled with 2DBP using Framework for Aquatic Biogeochemical Modelling (FABM). A depletion of MP from the surface water and acceleration of MP burying in summer period compared to the winter was simulated numerically. The calculations confirm the observations that the “biological pump” can be one of the important drivers controlling the quantity and the distribution of MP in the water column. Full article
(This article belongs to the Section Oceans and Coastal Zones)
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16 pages, 3924 KiB  
Article
Socioeconomic Impact Assessment of Water Resources Conservation and Management to Protect Groundwater in Punjab, Pakistan
by Javaria Nasir, Muhammad Ashfaq, Irfan Ahmad Baig, Jehangir F. Punthakey, Richard Culas, Asghar Ali and Faizan ul Hassan
Water 2021, 13(19), 2672; https://doi.org/10.3390/w13192672 - 27 Sep 2021
Cited by 14 | Viewed by 4893
Abstract
Water is the most important resource; it is utilized largely in agricultural production and is fundamental to ensuring global food security. This study aims to assess sustainable water management interventions and their impact on the farm economy. To increase water productivity, the most [...] Read more.
Water is the most important resource; it is utilized largely in agricultural production and is fundamental to ensuring global food security. This study aims to assess sustainable water management interventions and their impact on the farm economy. To increase water productivity, the most important adaptations that have been proposed are high-efficiency irrigation systems, drought-resistant varieties, the substitution of water-intensive crops with less water-demanding crops, the mulching of soil, zero tillage, and all on-farm operations that can save water, especially ground water. The recent analysis utilized farm survey data from 469 representative farmers along with secondary statistics. The data were collected via a multi-stage sampling technique to ensure the availability of representative farm populations based on a comprehensive site selection criterion. The TOA-MD model estimates the adoption rate of a proposed adaptation based on net farm returns. The impact of high-efficiency irrigation systems and the substitution of high delta crops for low delta crops had a positive impact on net farm returns and per capita income, and a negative impact on farm poverty in the study area. It is recommended that policymakers consult farmer representatives about agricultural and water-related issues so that all the policies can be implemented properly. Full article
(This article belongs to the Section Water Resources Management, Policy and Governance)
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16 pages, 6878 KiB  
Article
Wildfires as a Source of PAHs in Surface Waters of Background Areas (Lake Baikal, Russia)
by Alexander G. Gorshkov, Oksana N. Izosimova, Olga V. Kustova, Irina I. Marinaite, Yuri P. Galachyants, Valery N. Sinyukovich and Tamara V. Khodzher
Water 2021, 13(19), 2636; https://doi.org/10.3390/w13192636 - 25 Sep 2021
Cited by 20 | Viewed by 2984
Abstract
Polycyclic aromatic hydrocarbons (PAHs) were detected in different types of PAH-containing samples collected in Lake Baikal during wildfires in the adjacent areas. The set of studied samples included the following: (i) water from the upper layer (5 m); (ii) water from the surface [...] Read more.
Polycyclic aromatic hydrocarbons (PAHs) were detected in different types of PAH-containing samples collected in Lake Baikal during wildfires in the adjacent areas. The set of studied samples included the following: (i) water from the upper layer (5 m); (ii) water from the surface microlayer; (iii) water from the lake tributaries; (iv) water from deep layers (400 m); and (v) aerosol from the near-water layer. Ten PAHs were detected in the water samples: naphthalene, 1-methylnaphthalene, 2-methylnaphthalene acenaphthylene, acenaphthene, fluorene, phenanthrene, fluoranthene, pyrene, and chrysene. The total PAH concentrations (ƩPAHs) were detected in a wide range from 9.3 to 160 ng/L, characterizing by seasonal, intersessional, and spatial variability. In September 2016, the ƩPAH concentration in the southern basin of the lake reached 610 ng/L in the upper water layer due to an increase in fluorene, phenanthrene, fluoranthene, and pyrene in the composition of the PAHs. In June 2019, ƩPAHs in the water from the northern basin of the lake reached 290 ng/L, with the naphthalene and phenanthrene concentrations up to 170 ng/L and 92 ng/L, respectively. The calculation of back trajectories of the atmospheric transport near Lake Baikal, satellite images, and ƩPAH concentrations in the surface water microlayer of 150 to 960 ng/L confirm the impact of wildfires on Lake Baikal, with which the seasonal increase in the ƩPAH concentrations was associated in 2016 and 2019. The toxicity of PAHs detected in the water of the lake in extreme situations was characterized by the total value of the toxic equivalent for PAHs ranging from 0.17 to 0.22 ng/L, and a possible ecological risk of the impact on biota was assessed as moderate. Full article
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26 pages, 63296 KiB  
Article
A Novel Hybrid Model for Developing Groundwater Potentiality Model Using High Resolution Digital Elevation Model (DEM) Derived Factors
by Javed Mallick, Swapan Talukdar, Nabil Ben Kahla, Mohd. Ahmed, Majed Alsubih, Mohammed K. Almesfer and Abu Reza Md. Towfiqul Islam
Water 2021, 13(19), 2632; https://doi.org/10.3390/w13192632 - 25 Sep 2021
Cited by 16 | Viewed by 2881
Abstract
The present work aims to build a unique hybrid model by combining six fuzzy operator feature selection-based techniques with logistic regression (LR) for producing groundwater potential models (GPMs) utilising high resolution DEM-derived parameters in Saudi Arabia’s Bisha area. The current work focuses exclusively [...] Read more.
The present work aims to build a unique hybrid model by combining six fuzzy operator feature selection-based techniques with logistic regression (LR) for producing groundwater potential models (GPMs) utilising high resolution DEM-derived parameters in Saudi Arabia’s Bisha area. The current work focuses exclusively on the influence of DEM-derived parameters on GPMs modelling, without considering other variables. AND, OR, GAMMA 0.75, GAMMA 0.8, GAMMA 0.85, and GAMMA 0.9 are six hybrid models based on fuzzy feature selection. The GPMs were validated by using empirical and binormal receiver operating characteristic curves (ROC). An RF-based sensitivity analysis was performed in order to examine the influence of GPM settings. Six hybrid algorithms and one unique hybrid model have predicted 1835–2149 km2 as very high and 3235–4585 km2 as high groundwater potential regions. The AND model (ROCe-AUC: 0.81; ROCb-AUC: 0.804) outperformed the other models based on ROC’s area under curve (AUC). A novel hybrid model was constructed by combining six GPMs (considering as variables) with the LR model. The AUC of ROCe and ROCb revealed that the novel hybrid model outperformed existing fuzzy-based GPMs (ROCe: 0.866; ROCb: 0.892). With DEM-derived parameters, the present work will help to improve the effectiveness of GPMs for developing sustainable groundwater management plans. Full article
(This article belongs to the Section Hydrogeology)
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17 pages, 3947 KiB  
Article
A Case Study on Reliability, Water Demand and Economic Analysis of Rainwater Harvesting in Australian Capital Cities
by Preeti Preeti and Ataur Rahman
Water 2021, 13(19), 2606; https://doi.org/10.3390/w13192606 - 22 Sep 2021
Cited by 19 | Viewed by 4823
Abstract
This paper presents reliability, water demand and economic analysis of rainwater harvesting (RWH) systems for eight Australian capital cities (Adelaide, Brisbane, Canberra, Darwin, Hobart, Melbourne, Perth and Sydney). A Python-based tool is developed based on a daily water balance modelling approach, which uses [...] Read more.
This paper presents reliability, water demand and economic analysis of rainwater harvesting (RWH) systems for eight Australian capital cities (Adelaide, Brisbane, Canberra, Darwin, Hobart, Melbourne, Perth and Sydney). A Python-based tool is developed based on a daily water balance modelling approach, which uses input data such as daily rainfall, roof area, overflow losses, daily water demand and first flush. Ten different tank volumes are considered (1, 3, 5, 10, 15, 20, 30, 50, 75 and 100 m3). It is found that for a large roof area and tank size, the reliability of RWH systems for toilet and laundry use is high, in the range of 80–100%. However, the reliability for irrigation use is highly variable across all the locations. For combined use, Adelaide shows the smallest reliability (38–49%), while Hobart demonstrates the highest reliability (61–77%). Furthermore, economic analysis demonstrates that in a few cases, benefit–cost ratio values greater than one can be achieved for the RWH systems. The findings of this study will help the Australian Federal Government to enhance RWH policy, programs and subsidy levels considering climate-sensitive inputs in the respective cities. Full article
(This article belongs to the Special Issue Rainwater and Stormwater Harvesting for Sustainable Water Cycle Management)
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13 pages, 5846 KiB  
Article
Turbulent Flow through Random Vegetation on a Rough Bed
by Francesco Coscarella, Nadia Penna, Aldo Pedro Ferrante, Paola Gualtieri and Roberto Gaudio
Water 2021, 13(18), 2564; https://doi.org/10.3390/w13182564 - 17 Sep 2021
Cited by 11 | Viewed by 3112
Abstract
River vegetation radically modifies the flow field and turbulence characteristics. To analyze the vegetation effects on the flow, most scientific studies are based on laboratory tests or numerical simulations with vegetation stems on smooth beds. Nevertheless, in this manner, the effects of bed [...] Read more.
River vegetation radically modifies the flow field and turbulence characteristics. To analyze the vegetation effects on the flow, most scientific studies are based on laboratory tests or numerical simulations with vegetation stems on smooth beds. Nevertheless, in this manner, the effects of bed sediments are neglected. The aim of this paper is to experimentally investigate the effects of bed sediments in a vegetated channel and, in consideration of that, comparative experiments of velocity measures, performed with an Acoustic Doppler Velocimeter (ADV) profiler, were carried out in a laboratory flume with different uniform bed sediment sizes and the same pattern of randomly arranged emergent rigid vegetation. To better comprehend the time-averaged flow conditions, the time-averaged velocity was explored. Subsequently, the analysis was focused on the energetic characteristics of the flow field with the determination of the Turbulent Kinetic Energy (TKE) and its components, as well as of the energy spectra of the velocity components immediately downstream of a vegetation element. The results show that both the vegetation and bed roughness surface deeply affect the turbulence characteristics. Furthermore, it was revealed that the roughness influence becomes predominant as the grain size becomes larger. Full article
(This article belongs to the Special Issue Flow Hydrodynamic in Open Channels: Interaction with Natural or Man-Made Structures)
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22 pages, 1779 KiB  
Article
Nature-Based Solutions for Agriculture in Circular Cities: Challenges, Gaps, and Opportunities
by Alba Canet-Martí, Rocío Pineda-Martos, Ranka Junge, Katrin Bohn, Teresa A. Paço, Cecilia Delgado, Gitana Alenčikienė, Siv Lene Gangenes Skar and Gösta F. M. Baganz
Water 2021, 13(18), 2565; https://doi.org/10.3390/w13182565 - 17 Sep 2021
Cited by 25 | Viewed by 8594
Abstract
Urban agriculture (UA) plays a key role in the circular metabolism of cities, as it can use water resources, nutrients, and other materials recovered from streams that currently leave the city as solid waste or as wastewater to produce new food and biomass. [...] Read more.
Urban agriculture (UA) plays a key role in the circular metabolism of cities, as it can use water resources, nutrients, and other materials recovered from streams that currently leave the city as solid waste or as wastewater to produce new food and biomass. The ecosystem services of urban green spaces and infrastructures and the productivity of specific urban agricultural technologies have been discussed in literature. However, the understanding of input and output (I/O) streams of different nature-based solutions (NBS) is not yet sufficient to identify the challenges and opportunities they offer for strengthening circularity in UA. We propose a series of agriculture NBS, which, implemented in cities, would address circularity challenges in different urban spaces. To identify the challenges, gaps, and opportunities related to the enhancement of resources management of agriculture NBS, we evaluated NBS units, interventions, and supporting units, and analyzed I/O streams as links of urban circularity. A broader understanding of the food-related urban streams is important to recover resources and adapt the distribution system accordingly. As a result, we pinpointed the gaps that hinder the development of UA as a potential opportunity within the framework of the Circular City. Full article
(This article belongs to the Special Issue Water and Circular Cities)
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19 pages, 3024 KiB  
Article
Spoiled for Choice during Cold Season? Habitat Use and Potential Impacts of the Invasive Silurus glanis L. in a Deep, Large, and Oligotrophic Lake (Lake Maggiore, North Italy)
by Vanessa De Santis and Pietro Volta
Water 2021, 13(18), 2549; https://doi.org/10.3390/w13182549 - 17 Sep 2021
Cited by 15 | Viewed by 5143
Abstract
The ecological features of invasive alien species are crucial for their effective management. However, they are often lacking in newly invaded ecosystems. This is the case of the European catfish Silurus glanis L. in Lake Maggiore, where the species is present since 1990, [...] Read more.
The ecological features of invasive alien species are crucial for their effective management. However, they are often lacking in newly invaded ecosystems. This is the case of the European catfish Silurus glanis L. in Lake Maggiore, where the species is present since 1990, but no scientific information is available on its ecology. To start filling this knowledge gap, 236 catfish (67 cm to 150 cm of total length) were collected, measured, and dissected for stomach content analyses from three localities and in two habitats (littoral vs. pelagic) in late autumn/early winter. The NPUE and BPUE (individuals (N) and biomass (B, in grams) per unit effort (m2), respectively) of catfish were generally higher in littoral (NPUE > 0.01; BPUE > 96) than in pelagic habitats (NPUE < 0.009; BPUE < 114), but the catfish had, on average, larger sizes in pelagic habitats. Overall, 581 individual prey items were recorded, belonging to 12 taxa. Pelagic catfish specialized their diet exclusively on three prey fish (coregonids, shad, and roach), whilst the diet of littoral catfish was more variable and dominated by crayfish, perch, and roach. These results highlighted for the first time the interaction of larger catfish with the lake’s pelagic food web, and thus possible consequences are discussed, including the potential contrasting role S. glanis may have for the lake’s fishery. Full article
(This article belongs to the Special Issue Impacts of Human Activities and Climate Change on Freshwater Fish)
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15 pages, 3524 KiB  
Article
Evaluation of Vegetation Indices and Phenological Metrics Using Time-Series MODIS Data for Monitoring Vegetation Change in Punjab, Pakistan
by Pingbo Hu, Alireza Sharifi, Muhammad Naveed Tahir, Aqil Tariq, Lili Zhang, Faisal Mumtaz and Syed Hassan Iqbal Ahmad Shah
Water 2021, 13(18), 2550; https://doi.org/10.3390/w13182550 - 17 Sep 2021
Cited by 48 | Viewed by 5952
Abstract
In arid and semi-arid regions, it is essential to monitor the spatiotemporal variability and dynamics of vegetation. Among other provinces of Pakistan, Punjab has produced a significant number of crops. Recently, Punjab, Pakistan, has been described as a global hotspot for extremes of [...] Read more.
In arid and semi-arid regions, it is essential to monitor the spatiotemporal variability and dynamics of vegetation. Among other provinces of Pakistan, Punjab has produced a significant number of crops. Recently, Punjab, Pakistan, has been described as a global hotspot for extremes of climate change. In this study, the soil adjusted vegetation index (SAVI), normalized vegetation difference index (NDVI), and enhanced vegetation index (EVI) were comprehensively evaluated to monitor vegetation change in Punjab, Pakistan. The time-series MODIS (Moderate Resolution Imaging Spectroradiometer) data of different periods were used. The mean annual variability of the above vegetation indices (VIs) from 2000 to 2019 was evaluated and analyzed. For each type of vegetation, two phenological metrics (i.e., for the start of the season and end of the season) were calculated and compared. The spatio-temporal image analysis of the mean annual vegetation indices revealed similar patterns and varying vegetation conditions. In the forests and vegetation areas with sparse vegetation, the EVI showed high uncertainty. The phenological metrics of all vegetation indices were consistent for most types of vegetation. However, the NDVI result had the greatest variance between the start and end of season. The lowest annual VI variability was mainly observed in the southern part of the study area (less than 10% of the study area) based on the statistical analysis of spatial variability. The mean annual spatial variability of NDVI was <20%, SAVI was 30%, and EVI ranged between 10–20%. More than 40% of the variability was observed in the NDVI and SAVI vegetation indices. Full article
(This article belongs to the Special Issue Challenges and Opportunities to Overcome Global Water Crisis Particularly in Arid and Semi-arid Regions)
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20 pages, 1554 KiB  
Article
The Life Cycle Environmental Performance of On-Site or Decentralised Wastewater Treatment Systems for Domestic Homes
by John Gallagher and Laurence W. Gill
Water 2021, 13(18), 2542; https://doi.org/10.3390/w13182542 - 16 Sep 2021
Cited by 10 | Viewed by 3056
Abstract
There is little knowledge regarding the environmental sustainability of domestic on-site or decentralised wastewater treatment systems (DWWTS). This study evaluated six unique life cycle environmental impacts for different DWTTS configurations of five conventional septic tank systems, four packaged treatment units, and a willow [...] Read more.
There is little knowledge regarding the environmental sustainability of domestic on-site or decentralised wastewater treatment systems (DWWTS). This study evaluated six unique life cycle environmental impacts for different DWTTS configurations of five conventional septic tank systems, four packaged treatment units, and a willow evapotranspiration system. Similar freshwater eutrophication (FE), dissipated water (DW), and mineral and metal (MM), burdens were noted between the packaged and conventional system configurations, with the packaged systems demonstrating significantly higher impacts of between 18% and 56% for climate change (CC), marine eutrophication (ME), and fossils (F). At a system level, higher impacts were observed in systems requiring (i) three vs. two engineered treatment stages, (ii) a larger soil percolation trench area, and (iii) pumping of effluent. The evapotranspiration system presented the smallest total environmental impacts (3.0–10.8 lower), with net benefits for FE, ME, and MM identified due to the biomass (wood) production offsetting these burdens. Further analysis highlighted the sensitivity of results to biomass yield, operational demands (desludging or pumping energy demands), and embodied materials, with less significant impacts for replacing mechanical components, i.e., pumps. The findings highlighted the variation in environmental performance of different DWTTS configurations and indicated opportunities for design improvements to reduce their life cycle impacts. Full article
(This article belongs to the Special Issue On-Site Wastewater Treatment)
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21 pages, 6245 KiB  
Article
Assessment of Ensemble Models for Groundwater Potential Modeling and Prediction in a Karst Watershed
by Mohsen Farzin, Mohammadtaghi Avand, Hassan Ahmadzadeh, Martina Zelenakova and John P. Tiefenbacher
Water 2021, 13(18), 2540; https://doi.org/10.3390/w13182540 - 16 Sep 2021
Cited by 20 | Viewed by 2802
Abstract
Due to numerous droughts in recent years, the amount of surface water in arid and semi-arid regions has decreased significantly, so reliance on groundwater to meet local and regional demands has increased. The Kabgian watershed is a karst watershed in southwestern Iran that [...] Read more.
Due to numerous droughts in recent years, the amount of surface water in arid and semi-arid regions has decreased significantly, so reliance on groundwater to meet local and regional demands has increased. The Kabgian watershed is a karst watershed in southwestern Iran that provides a significant proportion of drinking and agriculture water supplies in the area. This study identified areas with karst groundwater potential using a combination of machine learning and statistical models, including entropy-SVM-LN, entropy-SVM-SG, and entropy-SVM-RBF. To do this, 384 karst springs were identified and mapped. Sixteen factors that are related to karst potential were identified from a review of the literature, and these were compiled for the study area. The 384 locations were randomly separated into two categories for training (269 location) and validation (115 location) datasets to be used in the modeling process. The ROC curve was used to evaluate the modeling results. The models used, in general, were good at determining the location of karst groundwater potential. The evaluation showed that the E-SVM-RBF model had an area under the curve of 0.92, indicating that it was most accurate estimator of groundwater potential among the ensemble models. Evaluation of the relative importance of each of the 16 factors revealed that land use, a vector ruggedness measure, curvature, and topography roughness index were the most important explainers of the presence of karst groundwater in the study area. It was also found that the factors affecting the presence of karst springs are significantly different from non-karst springs. Full article
(This article belongs to the Special Issue Assessment and Management of Flood Risk in Urban Areas)
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13 pages, 578 KiB  
Article
Key SARS-CoV-2 Mutations of Alpha, Gamma, and Eta Variants Detected in Urban Wastewaters in Italy by Long-Read Amplicon Sequencing Based on Nanopore Technology
by Giuseppina La Rosa, David Brandtner, Pamela Mancini, Carolina Veneri, Giusy Bonanno Ferraro, Lucia Bonadonna, Luca Lucentini and Elisabetta Suffredini
Water 2021, 13(18), 2503; https://doi.org/10.3390/w13182503 - 13 Sep 2021
Cited by 27 | Viewed by 5323
Abstract
The emergence of SARS-CoV-2 variants of concern (VOCs) and variants of interest (VOIs) poses an increased risk to global public health and underlines the need to prioritise monitoring and research to better respond to the COVID-19 pandemic. Wastewater monitoring can be used to [...] Read more.
The emergence of SARS-CoV-2 variants of concern (VOCs) and variants of interest (VOIs) poses an increased risk to global public health and underlines the need to prioritise monitoring and research to better respond to the COVID-19 pandemic. Wastewater monitoring can be used to monitor SARS-CoV-2 spread and to track SARS-CoV-2 variants. A long read amplicon sequencing approach based on the Oxford Nanopore technology, targeting the spike protein, was applied to detect SARS-CoV-2 variants in sewage samples collected in central Italy on April 2021. Next-generation sequencing was performed on three pooled samples. For variant identification, two approaches–clustering (unsupervised) and classification (supervised)–were implemented, resulting in the detection of two VOCs and one VOI. Key mutations of the Alpha variant (B.1.1.7) were detected in all of the pools, accounting for the vast majority of NGS reads. In two different pools, mutations of the Gamma (P.1) and Eta (B.1.525) variants were also detected, accounting for 22.4%, and 1.3% of total NGS reads of the sample, respectively. Results were in agreement with data on variant circulation in Italy at the time of wastewater sample collection. For each variant, in addition to the signature key spike mutations, other less common mutations were detected, including the amino acid substitutions S98F and E484K in the Alpha cluster (alone and combined), and S151I in the Eta cluster. Results of the present study show that the long-read sequencing nanopore technology can be successfully used to explore SARS-CoV-2 diversity in sewage samples, where multiple variants can be present, and that the approach is sensitive enough to detect variants present at low abundance in wastewater samples. In conclusion, wastewater monitoring can help one discover the spread of variants in a community and early detect the emerging of clinically relevant mutations or variants. Full article
(This article belongs to the Special Issue SARS-CoV-2 in Wastewater: Methods, Epidemiology and Future Goals)
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19 pages, 2796 KiB  
Article
Adapting Water Management to Climate Change in the Murray–Darling Basin, Australia
by Ian P. Prosser, Francis H. S. Chiew and Mark Stafford Smith
Water 2021, 13(18), 2504; https://doi.org/10.3390/w13182504 - 12 Sep 2021
Cited by 43 | Viewed by 8351
Abstract
Climate change is threatening water security in water-scarce regions across the world, challenging water management policy in terms of how best to adapt. Transformative new approaches have been proposed, but management policies remain largely the same in many instances, and there are claims [...] Read more.
Climate change is threatening water security in water-scarce regions across the world, challenging water management policy in terms of how best to adapt. Transformative new approaches have been proposed, but management policies remain largely the same in many instances, and there are claims that good current management practice is well adapted. This paper takes the case of the Murray–Darling Basin, Australia, where management policies are highly sophisticated and have been through a recent transformation in order to critically review how well adapted the basin’s management is to climate change. This paper synthesizes published data, recent literature, and water plans in order to evaluate the outcomes of water management policy. It identifies several limitations and inequities that could emerge in the context of climate change and, through synthesis of the broader climate adaptation literature, proposes solutions that can be implemented when basin management is formally reviewed in 2026. Full article
(This article belongs to the Special Issue Integrated Water Assessment and Management under Climate Change)
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17 pages, 54325 KiB  
Article
Efficient Hazard Assessment for Pluvial Floods in Urban Environments: A Benchmarking Case Study for the City of Berlin, Germany
by Omar Seleem, Maik Heistermann and Axel Bronstert
Water 2021, 13(18), 2476; https://doi.org/10.3390/w13182476 - 9 Sep 2021
Cited by 15 | Viewed by 4406
Abstract
The presence of impermeable surfaces in urban areas hinders natural drainage and directs the surface runoff to storm drainage systems with finite capacity, which makes these areas prone to pluvial flooding. The occurrence of pluvial flooding depends on the existence of minimal areas [...] Read more.
The presence of impermeable surfaces in urban areas hinders natural drainage and directs the surface runoff to storm drainage systems with finite capacity, which makes these areas prone to pluvial flooding. The occurrence of pluvial flooding depends on the existence of minimal areas for surface runoff generation and concentration. Detailed hydrologic and hydrodynamic simulations are computationally expensive and require intensive resources. This study compared and evaluated the performance of two simplified methods to identify urban pluvial flood-prone areas, namely the fill–spill–merge (FSM) method and the topographic wetness index (TWI) method and used the TELEMAC-2D hydrodynamic numerical model for benchmarking and validation. The FSM method uses common GIS operations to identify flood-prone depressions from a high-resolution digital elevation model (DEM). The TWI method employs the maximum likelihood method (MLE) to probabilistically calibrate a TWI threshold (τ) based on the inundation maps from a 2D hydrodynamic model for a given spatial window (W) within the urban area. We found that the FSM method clearly outperforms the TWI method both conceptually and effectively in terms of model performance. Full article
(This article belongs to the Special Issue Assessment and Management of Flood Risk in Urban Areas)
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21 pages, 1259 KiB  
Article
Transpiration and Water Use of an Irrigated Traditional Olive Grove with Sap-Flow Observations and the FAO56 Dual Crop Coefficient Approach
by Àngela Puig-Sirera, Giovanni Rallo, Paula Paredes, Teresa A. Paço, Mario Minacapilli, Giuseppe Provenzano and Luis S. Pereira
Water 2021, 13(18), 2466; https://doi.org/10.3390/w13182466 - 8 Sep 2021
Cited by 17 | Viewed by 3396
Abstract
The SIMDualKc model was applied to evaluate the crop water use and the crop coefficient (Kc) of an irrigated olive grove (Olea europaea L.) located in Sicily, Italy, using experimental data collected from two crop seasons. The model applies the [...] Read more.
The SIMDualKc model was applied to evaluate the crop water use and the crop coefficient (Kc) of an irrigated olive grove (Olea europaea L.) located in Sicily, Italy, using experimental data collected from two crop seasons. The model applies the FAO56 dual Kc approach to compute the actual crop evapotranspiration (ETc act) and its components, i.e., the actual tree transpiration (Tc act), obtained through the basal crop coefficient (Kcb), and soil evaporation according to an evaporation coefficient (Ke). Model calibration was performed by minimizing the difference between the predicted Tc act and the observed daily tree transpiration measured with sap flow instrumentation (TSF field) acquired in 2009. The validation was performed using the independent data set of sap flow measurements from 2011. The calibrated Kcb was equal to 0.30 for the initial and non-growing season stages, 0.42 for the mid-season, and 0.37 for the end season. For both seasons, the goodness-of-fit indicators relative to comparing TSF field with the simulated Tc act resulted in root mean square errors (RMSE) lower than 0.27 mm d−1 and a slope of the linear regression close to 1.0 (0.94 ≤ b0 ≤ 1.00). The olive grove water balance simulated with SIMDualKc produced a ratio between soil evaporation (Es) and ETc act that averaged 39%. The ratio between actual (ETc act) and potential crop evapotranspiration (ETc) varied from 84% to about 99% in the mid-season, indicating that the values of ETc act are close to ETc, i.e., the adopted deficit irrigation led to limited water stress. The results confirm the suitability of the SIMDualKc model to apply the FAO56 dual Kc approach to tree crops, thus assessing the water use of olives and supporting the development of appropriate irrigation management tools that are usable by farmers. A different way to estimate Kcb is based on the approach suggested in 2009 by Allen and Pereira (A&P), which involves the measured fraction of ground covered (shaded) by the crop and the height of the trees. Its application to the studied grove produced the mid-season Kcb values ranging from 0.40–0.45 and end-season Kcb values ranging from 0.35–0.40. The comparison between the A&P-computed Tc act A&P and TSF field shows RMSE values ranging from 0.27 to 0.43 mm d−1, which demonstrates the adequacy of the latter approach for parameterizing water balance models and for irrigation scheduling decision making. Full article
(This article belongs to the Special Issue Applications of Agro-Hydrological Sensors and Models for Sustainable Irrigation)
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19 pages, 5171 KiB  
Article
Investigation of Groundwater Depletion in the State of Qatar and Its Implication to Energy Water and Food Nexus
by Hazrat Bilal, Rajesh Govindan and Tareq Al-Ansari
Water 2021, 13(18), 2464; https://doi.org/10.3390/w13182464 - 8 Sep 2021
Cited by 25 | Viewed by 5317
Abstract
Groundwater is a precious freshwater resource heavily relied upon by agricultural activities in many parts of the world, and especially by countries with limited water resources located in arid regions. Groundwater resources are under severe pressures due to population increase, urbanisation and socio-economic [...] Read more.
Groundwater is a precious freshwater resource heavily relied upon by agricultural activities in many parts of the world, and especially by countries with limited water resources located in arid regions. Groundwater resources are under severe pressures due to population increase, urbanisation and socio-economic development, with potential for causing long-term threats to human life and natural ecosystems. This study attempts to investigate the impacts of local and regional climatic trends, and establish key forcing functions that have changed local groundwater resources. The main questions answered through this study include: Are these changes beneficial or detrimental? If they are detrimental, what is the future outlook for impacts on the ecosystem? What are the corrective actions needed to avert the long-term risks in arid environments? In view of this, the methodology developed in this study focuses on a joint time-series statistical analysis using ground data as well as Gravity Recovery and Climate Experiment (GRACE) satellite data. Results show a substantial depletion in the groundwater thickness (0.24 ± 0.20 cm/year) during the period of observation (2002–2020). Long-term temperature data indicates that the annual mean temperature increased significantly by 1.02 °C between 1987 and 2016, while total rainfall exhibited a slight decreasing trend. In addition to groundwater extraction, fluctuations in monthly rainfall, soil moisture, evapotranspiration and relative humidity support the groundwater thickness reduction of GRACE datasets. The use of desalinated water and wastewater reuse in the agriculture sector may reduce the pressure on groundwater resources. Optimization, adaptation and mitigation in the EWF nexus will further improve the sustainability of the EWF resources. Full article
(This article belongs to the Section Hydrology)
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17 pages, 2625 KiB  
Article
Advanced Oxidation Processes Based on Sulfate Radicals for Wastewater Treatment: Research Trends
by Lizeth Urán-Duque, Julio César Saldarriaga-Molina and Ainhoa Rubio-Clemente
Water 2021, 13(17), 2445; https://doi.org/10.3390/w13172445 - 6 Sep 2021
Cited by 20 | Viewed by 4648
Abstract
In this work, the recent trends in the application of the sulfate radical-based advanced oxidation processes (SR-AOPs) for the treatment of wastewater polluted with emerging contaminants (ECs) and pathogenic load were systematically studied due to the high oxidizing power ascribed to these technologies. [...] Read more.
In this work, the recent trends in the application of the sulfate radical-based advanced oxidation processes (SR-AOPs) for the treatment of wastewater polluted with emerging contaminants (ECs) and pathogenic load were systematically studied due to the high oxidizing power ascribed to these technologies. Additionally, because of the economic benefits and the synergies presented in terms of efficiency in ECs degradation and pathogen inactivation, the combination of the referred to AOPs and conventional treatments, including biological processes, was covered. Finally, the barriers and limitations related to the implementation of SR-AOPs were described, highlighting the still scarce full-scale implementation and the high operating-costs associated, especially when solar energy cannot be used in the oxidation systems. Full article
(This article belongs to the Special Issue AOP Processes for Organics Removal in Water and Wastewater)
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25 pages, 8285 KiB  
Article
Predicting Inflow Rate of the Soyang River Dam Using Deep Learning Techniques
by Sangwon Lee and Jaekwang Kim
Water 2021, 13(17), 2447; https://doi.org/10.3390/w13172447 - 6 Sep 2021
Cited by 16 | Viewed by 3545
Abstract
The Soyang Dam, the largest multipurpose dam in Korea, faces water resource management challenges due to global warming. Global warming increases the duration and frequency of days with high temperatures and extreme precipitation events. Therefore, it is crucial to accurately predict the inflow [...] Read more.
The Soyang Dam, the largest multipurpose dam in Korea, faces water resource management challenges due to global warming. Global warming increases the duration and frequency of days with high temperatures and extreme precipitation events. Therefore, it is crucial to accurately predict the inflow rate for water resource management because it helps plan for flood, drought, and power generation in the Seoul metropolitan area. However, the lack of hydrological data for the Soyang River Dam causes a physical-based model to predict the inflow rate inaccurately. This study uses nearly 15 years of meteorological, dam, and weather warning data to overcome the lack of hydrological data and predict the inflow rate over two days. In addition, a sequence-to-sequence (Seq2Seq) mechanism combined with a bidirectional long short-term memory (LSTM) is developed to predict the inflow rate. The proposed model exhibits state-of-the-art prediction accuracy with root mean square error (RMSE) of 44.17 m3/s and 58.59 m3/s, mean absolute error (MAE) of 14.94 m3/s and 17.11 m3/s, and Nash–Sutcliffe efficiency (NSE) of 0.96 and 0.94, for forecasting first and second day, respectively. Full article
(This article belongs to the Section Hydrology)
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15 pages, 2123 KiB  
Article
Dual Benefit of Rainwater Harvesting—High Temporal-Resolution Stochastic Modelling
by Ofer Snir and Eran Friedler
Water 2021, 13(17), 2415; https://doi.org/10.3390/w13172415 - 2 Sep 2021
Cited by 7 | Viewed by 7093
Abstract
The objective of the presented study was to develop a high-temporal-resolution stochastic rainwater harvesting (RWH) model for assessing the dual benefits of RWH: potable water savings and runoff reduction. Model inputs of rainfall and water demand are used in a stochastic manner, maintaining [...] Read more.
The objective of the presented study was to develop a high-temporal-resolution stochastic rainwater harvesting (RWH) model for assessing the dual benefits of RWH: potable water savings and runoff reduction. Model inputs of rainfall and water demand are used in a stochastic manner, maintaining their natural pattern, while generating realistic noise and temporal variability. The dynamic model solves a mass-balance equation for the rainwater tank, while logging all inflows and outflows from it for post-simulation analysis. The developed model can simulate various building sizes, roof areas, rainwater tank volumes, controlled release policies, and time periods, providing a platform for assessing short- and long-term benefits. Standard passive rainwater harvesting operation and real-time control policies (controlled release) are demonstrated for a 40-apartment building with rainfall data typical for a Mediterranean climate, showing the system’s ability to supply water for non-potable uses, while reducing runoff volumes and flows, with the latter significantly improved when water is intentionally released from the tank prior to an expected overflow. The model could be used to further investigate the effects of rainwater harvesting on the urban water cycle, by coupling it with an urban drainage model and simulating the operation of a distributed network of micro-reservoirs that supply water and mitigate floods. Full article
(This article belongs to the Section Urban Water Management)
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20 pages, 5190 KiB  
Article
Hydrological Responses of Watershed to Historical and Future Land Use Land Cover Change Dynamics of Nashe Watershed, Ethiopia
by Megersa Kebede Leta, Tamene Adugna Demissie and Jens Tränckner
Water 2021, 13(17), 2372; https://doi.org/10.3390/w13172372 - 29 Aug 2021
Cited by 45 | Viewed by 5640
Abstract
Land use land cover (LULC) change is the crucial driving force that affects the hydrological processes of a watershed. The changes of LULC have an important influence and are the main factor for monitoring the water balances. The assessment of LULC change is [...] Read more.
Land use land cover (LULC) change is the crucial driving force that affects the hydrological processes of a watershed. The changes of LULC have an important influence and are the main factor for monitoring the water balances. The assessment of LULC change is indispensable for sustainable development of land and water resources. Understanding the watershed responses to environmental changes and impacts of LULC classes on hydrological components is vigorous for planning water resources, land resource utilization, and hydrological balance sustaining. In this study, LULC effects on hydrological parameters of the Nashe watershed, Blue Nile River Basin are investigated. For this, historical and future LULC change scenarios in the Nashe watershed are implemented into a calibrated Soil and Water Assessment Tool (SWAT) model. Five LULC scenarios have been developed that represent baseline, current, and future periods corresponding to the map of 1990, 2005, 2019, 2035, and 2050. The predicted increase of agricultural and urban land by decreasing mainly forest land will lead till 2035 to an increase of 2.33% in surface runoff and a decline in ground water flow, lateral flow, and evapotranspiration. Between 2035 and 2050, a gradual increase of grass land and range land could mitigate the undesired tendency. The applied combination of LULC prognosis with process-based hydrologic modeling provide valuable data about the current and future understanding of variation in hydrological parameters and assist concerned bodies to improve land and water management in formulating approaches to minimize the conceivable increment of surface runoff. Full article
(This article belongs to the Special Issue Hydrological Processes in Small Catchments—Runoff and Sediment Yield in Changing Environment)
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29 pages, 8889 KiB  
Article
Evaluation of Pollutant Removal Efficiency by Small-Scale Nature-Based Solutions Focusing on Bio-Retention Cells, Vegetative Swale and Porous Pavement
by Anik Dutta, Arlex Sanchez Torres and Zoran Vojinovic
Water 2021, 13(17), 2361; https://doi.org/10.3390/w13172361 - 28 Aug 2021
Cited by 15 | Viewed by 6268
Abstract
Rapid urbanization, aging infrastructure, and changes in rainfall patterns linked to climate change have brought considerable challenges to water managers around the world. Impacts from such drivers are likely to increase even further unless the appropriate actions are put in place. Floods, landslides, [...] Read more.
Rapid urbanization, aging infrastructure, and changes in rainfall patterns linked to climate change have brought considerable challenges to water managers around the world. Impacts from such drivers are likely to increase even further unless the appropriate actions are put in place. Floods, landslides, droughts and water pollution are just a few examples of such impacts and their corresponding consequences are in many cases devastating. At the same time, it has become a well-accepted fact that traditional (i.e., grey infrastructure) measures are no longer effective in responding to such challenges. Nature-based solutions (NBS) have emerged as a new response towards hydro-meteorological risk reduction and the results obtained to date are encouraging. However, their application has been mainly in the area of water quantity management with few studies that report on their efficiency to deal with water quality aspects. These solutions are based on replicating natural phenomena and processes to solve such problems. The present paper addresses the question of three NBS systems, namely, bio-retention cells, vegetative swales and porous pavements, for the removal of total suspended solids (TSS), total nitrogen (TN) and total phosphorus (TP) when applied in different configurations (single or networked). The results presented in this paper aim to advance the understanding of their performances during varying rainfall patterns and configurations and their potential application conditions. Full article
(This article belongs to the Special Issue Hydrologic and Water Quality Performance of Stormwater Best Management Practices)
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19 pages, 9487 KiB  
Article
Future Changes in Precipitation Extremes over East Africa Based on CMIP6 Models
by Brian Ayugi, Victor Dike, Hamida Ngoma, Hassen Babaousmail, Richard Mumo and Victor Ongoma
Water 2021, 13(17), 2358; https://doi.org/10.3390/w13172358 - 27 Aug 2021
Cited by 59 | Viewed by 6839
Abstract
This paper presents an analysis of projected precipitation extremes over the East African region. The study employs six indices defined by the Expert Team on Climate Change Detection Indices to evaluate extreme precipitation. Observed datasets and Coupled Model Intercomparison Project Phase six (CMIP6) [...] Read more.
This paper presents an analysis of projected precipitation extremes over the East African region. The study employs six indices defined by the Expert Team on Climate Change Detection Indices to evaluate extreme precipitation. Observed datasets and Coupled Model Intercomparison Project Phase six (CMIP6) simulations are employed to assess the changes during the two main rainfall seasons: March to May (MAM) and October to December (OND). The results show an increase in consecutive dry days (CDD) and decrease in consecutive wet days (CWD) towards the end of the 21st century (2081–2100) relative to the baseline period (1995–2014) in both seasons. Moreover, simple daily intensity (SDII), very wet days (R95 p), very heavy precipitation >20 mm (R20 mm), and total wet-day precipitation (PRCPTOT) demonstrate significant changes during OND compared to the MAM season. The spatial variation for extreme incidences shows likely intensification over Uganda and most parts of Kenya, while a reduction is observed over the Tanzania region. The increase in projected extremes may pose a serious threat to the sustainability of societal infrastructure and ecosystem wellbeing. The results from these analyses present an opportunity to understand the emergence of extreme events and the capability of model outputs from CMIP6 in estimating the projected changes. More studies are recommended to examine the underlying physical features modulating the occurrence of extreme incidences projected for relevant policies. Full article
(This article belongs to the Special Issue Hydrological Extremes under Climate Change and Socioeconomic Developments in Developing Countries)
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24 pages, 3607 KiB  
Article
Removal of Pharmaceuticals from Wastewater: Analysis of the Past and Present Global Research Activities
by Juan Carlos Leyva-Díaz, Ana Batlles-delaFuente, Valentín Molina-Moreno, Jorge Sánchez Molina and Luis J. Belmonte-Ureña
Water 2021, 13(17), 2353; https://doi.org/10.3390/w13172353 - 27 Aug 2021
Cited by 13 | Viewed by 4816
Abstract
Water pollution is a worldwide problem. Water consumption increases at a faster rate than population and this leads to a higher pollution rate. Sustainable Development Goals (SDG) include proposals aimed at ensuring the availability of clean water and its sustainable management (Goal 6), [...] Read more.
Water pollution is a worldwide problem. Water consumption increases at a faster rate than population and this leads to a higher pollution rate. Sustainable Development Goals (SDG) include proposals aimed at ensuring the availability of clean water and its sustainable management (Goal 6), as well as the conservation and sustainable use of oceans and seas. The current trend consists in trying to reconcile economic growth with sustainability, avoiding the negative externalities for the environment generated by human activity. More specifically, the objective of this article is to present the evolution of the research regarding the removal of polluting pharmaceuticals that are discharged into wastewater. To do that, a bibliometric analysis of 2938 articles comprising the period 1979–2020 has been carried out. This analysis includes productivity indicators in the scientific field: journals, authors, research institutions and countries. In addition, keyword analysis allows the identification of four main axes of the research regarding the removal of pharmaceutical residues found in wastewater. The first group of articles is aimed at identifying the pharmaceuticals present in polluting effluents. The second and third groups of articles focus on presenting the procedures that enable the treatment of emerging contaminants, either from a biological point of view (second group) or a physicochemical point of view (third group). The fourth group refers to water quality and its possibilities to be reused. Finally, there is a growing trend of worldwide scientific publications, which justifies the importance of polluting residues management, especially those of pharmaceutical origin, in order to achieve a more sustainable society. Full article
(This article belongs to the Special Issue Biological Treatments for the Removal of Contaminants of Emerging Concern from Wastewater)
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18 pages, 15053 KiB  
Article
Flood Disaster Risk Perception and Urban Households’ Flood Disaster Preparedness: The Case of Accra Metropolis in Ghana
by Qi Yin, Gideon Ntim-Amo, Ruiping Ran, Dingde Xu, Stephen Ansah, Jinfu Hu and Hong Tang
Water 2021, 13(17), 2328; https://doi.org/10.3390/w13172328 - 25 Aug 2021
Cited by 33 | Viewed by 8556
Abstract
Flood disaster has gained global attention due to the huge impact it has on human lives, economies, and sustainable environments. Flood disaster preparedness, which can significantly be influenced by disaster risk perception, has been highlighted as an effective way to manage flood disaster [...] Read more.
Flood disaster has gained global attention due to the huge impact it has on human lives, economies, and sustainable environments. Flood disaster preparedness, which can significantly be influenced by disaster risk perception, has been highlighted as an effective way to manage flood disaster risk, as many other means have proved futile, yet no study has attempted using multiple dimensions to analyze this relationship in Ghana. Therefore, this study, using a survey of 369 households in the most flood-prone region, Accra Metropolis, analyzed the influence of flood disaster risk perception on urban households’ flood disaster preparedness. Based on the Protective Action Decision Model, the empirical models were constructed and estimated using the Tobit and binary logistic regression models. The results show that the majority of households (60.16%) were unprepared for flood disasters, and the perception of flood disaster risk and the sustainability risk posed by floods significantly affect flood disaster preparedness behaviours of households in a positive direction. The total number of flood disaster preparedness behaviours adopted was significantly related to probability, the threat to lives, sense of worry, and sustainability risk perceptions. Finally, income, education, and house ownership, among other household and individual characteristics, had significant positive effects on preparations for flood disasters. These findings suggest that effective policies to mitigate flood disasters must incorporate risk communication to boost households’ flood disaster preparedness. Full article
(This article belongs to the Special Issue Sustainable Development and Disaster Risk Reduction)
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27 pages, 5700 KiB  
Article
A New Framework for Modelling Fine Sediment Transport in Rivers Includes Flocculation to Inform Reservoir Management in Wildfire Impacted Watersheds
by Micheal Stone, Bommanna G. Krishnappan, Uldis Silins, Monica B. Emelko, Chris H. S. Williams, Adrian L. Collins and Sheena A. Spencer
Water 2021, 13(17), 2319; https://doi.org/10.3390/w13172319 - 24 Aug 2021
Cited by 13 | Viewed by 4738
Abstract
Fine-grained cohesive sediment is the primary vector for nutrient and contaminant redistribution through aquatic systems and is a critical indicator of land disturbance. A critical limitation of most existing sediment transport models is that they assume that the transport characteristics of fine sediment [...] Read more.
Fine-grained cohesive sediment is the primary vector for nutrient and contaminant redistribution through aquatic systems and is a critical indicator of land disturbance. A critical limitation of most existing sediment transport models is that they assume that the transport characteristics of fine sediment can be described using the same approaches that are used for coarse-grained non-cohesive sediment, thereby ignoring the tendency of fine sediment to flocculate. Here, a modelling framework to simulate flow and fine sediment transport in the Crowsnest River, the Castle River, the Oldman River and the Oldman Reservoir after the 2003 Lost Creek wildfire in Alberta, Canada was developed and validated. It is the first to include explicit description of fine sediment deposition/erosion processes as a function of bed shear stress and the flocculation process. This framework integrates four existing numerical models: MOBED, RIVFLOC, RMA2 and RMA4 using river geometry, flow, fine suspended sediment characteristics and bathymetry data. Sediment concentration and particle size distributions computed by RIVFLOC were used as the upstream boundary condition for the reservoir dispersion model RMA4. The predicted particle size distributions and mass of fine river sediment deposited within various sections of the reservoir indicate that most of the fine sediment generated by the upstream disturbance deposits in the reservoir. Deposition patterns of sediment from wildfire-impacted landscapes were different than those from unburned landscapes because of differences in settling behaviour. These differences may lead to zones of relatively increased internal loading of phosphorus to reservoir water columns, thereby increasing the potential for algae proliferation. In light of the growing threats to water resources globally from wildfire, the generic framework described herein can be used to model propagation of fine river sediment and associated nutrients or contaminants to reservoirs under different flow conditions and land use scenarios. The framework is thereby a valuable tool to support decision making for water resources management and catchment planning. Full article
(This article belongs to the Special Issue Modelling of River Flows, Sediment and Contaminants Transport)
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20 pages, 4309 KiB  
Article
Monitoring Land Use Changes and Their Future Prospects Using GIS and ANN-CA for Perak River Basin, Malaysia
by Muhammad Talha Zeshan, Muhammad Raza Ul Mustafa and Mohammed Feras Baig
Water 2021, 13(16), 2286; https://doi.org/10.3390/w13162286 - 21 Aug 2021
Cited by 34 | Viewed by 6117
Abstract
Natural landscapes have changed significantly through anthropogenic activities, particularly in areas that are severely impacted by climate change and population expansion, such as countries in Southeast Asia. It is essential for sustainable development, particularly efficient water management practices, to know about the impact [...] Read more.
Natural landscapes have changed significantly through anthropogenic activities, particularly in areas that are severely impacted by climate change and population expansion, such as countries in Southeast Asia. It is essential for sustainable development, particularly efficient water management practices, to know about the impact of land use and land cover (LULC) changes. Geographic information systems (GIS) and remote sensing were used for monitoring land use changes, whereas artificial neural network cellular automata (ANN-CA) modeling using quantum geographic information systems (QGIS) was performed for prediction of LULC changes. This study investigated the changes in LULC in the Perak River basin for the years 2000, 2010, and 2020. The study also provides predictions of future changes for the years 2030, 2040, and 2050. Landsat satellite images were utilized to monitor the land use changes. For the classification of Landsat images, maximum-likelihood supervised classification was implemented. The broad classification defines four main classes in the study area, including (i) waterbodies, (ii) agricultural lands, (iii) barren and urban lands, and (iv) dense forests. The outcomes revealed a considerable reduction in dense forests from the year 2000 to 2020, whereas a substantial increase in barren lands (up to 547.39 km2) had occurred by the year 2020, while urban land use has seen a rapid rise. The kappa coefficient was used to assess the validity of classified images, with an overall kappa coefficient of 0.86, 0.88, and 0.91 for the years 2000, 2010, and 2020, respectively. In addition, ANN-CA simulation results predicted that barren and urban lands will expand in the future at the expense of other classes in the years 2030, 2040, and 2050. However, a considerable decrease will occur in the area of dense forests in the simulated years. The study successfully presents LULC changes and future predictions highlighting significant pattern of land use change in the Perak River basin. This information could be helpful for land use administration and future planning in the region. Full article
(This article belongs to the Section Hydrology)
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13 pages, 5136 KiB  
Article
Numerical Investigation of Surge Waves Generated by Submarine Debris Flows
by Zili Dai, Jinwei Xie, Shiwei Qin and Shuyang Chen
Water 2021, 13(16), 2276; https://doi.org/10.3390/w13162276 - 20 Aug 2021
Cited by 5 | Viewed by 2750
Abstract
Submarine debris flows and their generated waves are common disasters in Nature that may destroy offshore infrastructure and cause fatalities. As the propagation of submarine debris flows is complex, involving granular material sliding and wave generation, it is difficult to simulate the process [...] Read more.
Submarine debris flows and their generated waves are common disasters in Nature that may destroy offshore infrastructure and cause fatalities. As the propagation of submarine debris flows is complex, involving granular material sliding and wave generation, it is difficult to simulate the process using conventional numerical models. In this study, a numerical model based on the smoothed particle hydrodynamics (SPH) algorithm is proposed to simulate the propagation of submarine debris flow and predict its generated waves. This model contains the Bingham fluid model for granular material, the Newtonian fluid model for the ambient water, and a multiphase granular flow algorithm. Moreover, a boundary treatment technique is applied to consider the repulsive force from the solid boundary. Underwater rigid block slide and underwater sand flow were simulated as numerical examples to verify the proposed SPH model. The computed wave profiles were compared with the observed results recorded in references. The good agreement between the numerical results and experimental data indicates the stability and accuracy of the proposed SPH model. Full article
(This article belongs to the Special Issue Mechanism and Prevention of Debris Flow Disaster)
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29 pages, 13826 KiB  
Article
Can Managed Aquifer Recharge Overcome Multiple Droughts?
by Mengqi Zhao, Jan Boll, Jennifer C. Adam and Allyson Beall King
Water 2021, 13(16), 2278; https://doi.org/10.3390/w13162278 - 20 Aug 2021
Cited by 7 | Viewed by 3403
Abstract
Frequent droughts, seasonal precipitation, and growing agricultural water demand in the Yakima River Basin (YRB), located in Washington State, increase the challenges of optimizing water provision for agricultural producers. Increasing water storage through managed aquifer recharge (MAR) can potentially relief water stress from [...] Read more.
Frequent droughts, seasonal precipitation, and growing agricultural water demand in the Yakima River Basin (YRB), located in Washington State, increase the challenges of optimizing water provision for agricultural producers. Increasing water storage through managed aquifer recharge (MAR) can potentially relief water stress from single and multi-year droughts. In this study, we developed an aggregated water resources management tool using a System Dynamics (SD) framework for the YRB and evaluated the MAR implementation strategy and the effectiveness of MAR in alleviating drought impacts on irrigation reliability. The SD model allocates available water resources to meet instream target flows, hydropower demands, and irrigation demand, based on system operation rules, irrigation scheduling, water rights, and MAR adoption. Our findings suggest that the adopted infiltration area for MAR is one of the main factors that determines the amount of water withdrawn and infiltrated to the groundwater system. The implementation time frame is also critical in accumulating MAR entitlements for single-year and multi-year droughts mitigation. In addition, adoption behaviors drive a positive feedback that MAR effectiveness on drought mitigation will encourage more MAR adoptions in the long run. MAR serves as a promising option for water storage management and a long-term strategy for MAR implementation can improve system resilience to unexpected droughts. Full article
(This article belongs to the Special Issue Water Resources Systems in a Changing World: Planning and Adaptation)
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17 pages, 3439 KiB  
Article
A Spatial Integrated SLR Adaptive Management Plan Framework (SISAMP) toward Sustainable Coasts
by Lida Davar, Gary Griggs, Afshin Danehkar, Abdolrassoul Salmanmahiny, Hossein Azarnivand and Babak Naimi
Water 2021, 13(16), 2263; https://doi.org/10.3390/w13162263 - 19 Aug 2021
Cited by 6 | Viewed by 3636
Abstract
Sea-level rise (SLR) is known as a central part of the Earth’s response to human-induced global warming and is projected to continue to rise over the twenty-first century and beyond. The importance of coastal areas for both human and natural systems has led [...] Read more.
Sea-level rise (SLR) is known as a central part of the Earth’s response to human-induced global warming and is projected to continue to rise over the twenty-first century and beyond. The importance of coastal areas for both human and natural systems has led researchers to conduct extensive studies on coastal vulnerability to SLR impacts and develop adaptation options to cope with rising sea level. Investigations to date have focused mostly on developed and highly populated coasts, as well as diverse ecosystems including tidal salt marshes and mangroves. As a result, there is less information on vulnerability and adaptation of less-developed and developing coasts to sea-level rise and its associated impacts. Hence, this research aimed at outlining an appropriate coastal management framework to adapt to SLR on the coasts that are in the early stage of development. A coastal area with a low level of development, located in southern Iran along the Gulf of Oman, was selected as a case study. The types of lands exposed to the high-end estimates of SLR by 2100 were identified and used as the primary criteria in determining the practical adaptation approaches for developing coasts. The result of coastal exposure assessment showed that, of five exposed land cover types, bare land, which is potentially considered for development, has the highest percentage of exposure to future sea-level rise. In order to protect the exposed coastal lands from future development and increase adaptive capacity of coastal systems, we developed a Spatial Integrated SLR Adaptive Management Plan Framework (SISAMP) based on an exposure reduction approach. Spatial land management tools and coastal exposure assessment models along with three other key components were integrated into the proposed conceptual framework to reduce coastal vulnerability through minimizing exposure of coastal communities to SLR-induced impacts. This adaptation plan provides a comprehensive approach for sustainable coastal management in a changing climate, particularly on developing coasts. Full article
(This article belongs to the Special Issue Adaptation to Coastal Climate Change and Sea-Level Rise)
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37 pages, 14478 KiB  
Article
Spatial Prediction of Groundwater Potentiality in Large Semi-Arid and Karstic Mountainous Region Using Machine Learning Models
by Mustapha Namous, Mohammed Hssaisoune, Biswajeet Pradhan, Chang-Wook Lee, Abdullah Alamri, Abdenbi Elaloui, Mohamed Edahbi, Samira Krimissa, Hasna Eloudi, Mustapha Ouayah, Hicham Elhimer and Tarik Tagma
Water 2021, 13(16), 2273; https://doi.org/10.3390/w13162273 - 19 Aug 2021
Cited by 31 | Viewed by 3763
Abstract
The drinking and irrigation water scarcity is a major global issue, particularly in arid and semi-arid zones. In rural areas, groundwater could be used as an alternative and additional water supply source in order to reduce human suffering in terms of water scarcity. [...] Read more.
The drinking and irrigation water scarcity is a major global issue, particularly in arid and semi-arid zones. In rural areas, groundwater could be used as an alternative and additional water supply source in order to reduce human suffering in terms of water scarcity. In this context, the purpose of the present study is to facilitate groundwater potentiality mapping via spatial-modelling techniques, individual and ensemble machine-learning models. Random forest (RF), logistic regression (LR), decision tree (DT) and artificial neural networks (ANNs) are the main algorithms used in this study. The preparation of groundwater potentiality maps was assembled into 11 ensembles of models. Overall, about 374 groundwater springs was identified and inventoried in the mountain area. The spring inventory data was randomly divided into training (75%) and testing (25%) datasets. Twenty-four groundwater influencing factors (GIFs) were selected based on a multicollinearity test and the information gain calculation. The results of the groundwater potentiality mapping were validated using statistical measures and the receiver operating characteristic curve (ROC) method. Finally, a ranking of the 15 models was achieved with the prioritization rank method using the compound factor (CF) method. The ensembles of models are the most stable and suitable for groundwater potentiality mapping in mountainous aquifers compared to individual models based on success and prediction rate. The most efficient model using the area under the curve validation method is the RF-LR-DT-ANN ensemble of models. Moreover, the results of the prioritization rank indicate that the best models are the RF-DT and RF-LR-DT ensembles of models. Full article
(This article belongs to the Special Issue Geo-Environmental Approaches for the Analysis and Assessment of Groundwater Resources at Catchment-Scale)
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22 pages, 15332 KiB  
Article
Integration of Water Quality Indices and Multivariate Modeling for Assessing Surface Water Quality in Qaroun Lake, Egypt
by Mohamed Gad, Magda M. Abou El-Safa, Mohamed Farouk, Hend Hussein, Ashwaq M. Alnemari, Salah Elsayed, Moataz M. Khalifa, Farahat S. Moghanm, Ebrahem M. Eid and Ali H. Saleh
Water 2021, 13(16), 2258; https://doi.org/10.3390/w13162258 - 18 Aug 2021
Cited by 71 | Viewed by 4593
Abstract
Water quality has deteriorated in recent years as a result of rising population and unplanned development, impacting ecosystem health. The water quality parameters of Qaroun Lake are contaminated to varying degrees, particularly for aquatic life consumption. For that, the objective of this work [...] Read more.
Water quality has deteriorated in recent years as a result of rising population and unplanned development, impacting ecosystem health. The water quality parameters of Qaroun Lake are contaminated to varying degrees, particularly for aquatic life consumption. For that, the objective of this work is to improve the assessments of surface water quality and to determine the different geo-environmental parameters affecting the lake environmental system in Qaroun Lake utilizing the weighted arithmetic water quality index (WAWQI) and four pollution indices (heavy metal pollution index (HPI), metal index (MI), contamination index (Cd), and pollution index (PI), that are enhanced by multivariate analyses as cluster analysis (CA), principal component analysis (PCA), and support vector machine regression (SVMR). Surface water samples were collected at 16 different locations from the lake during years 2018 and 2019. Thirteen physiochemical parameters were measured and used to calculate water quality indices (WQIs). The WQIs of Qaroun Lake such WAWQI, HPI, MI, Cd, PI revealed a different degree of contamination, with respect to aquatic life utilization. The WQIs result revealed that surface water in the lake is unsuitable, high polluted, and seriously affected by pollution for an aquatic environment. The PI findings revealed that surface water samples of Qaroun Lake were significantly impacted by Al, moderately affected by Cd and Cu, and while slightly affected by Zn due to uncontrolled releases of domestic and industrial wastewater. Furthermore, increasing salinity accelerates the deterioration of the lake aquatic environment. Therefore, sewage and drainage wastewater should be treated before discharging into the lake. The SVMR models based on physiochemical parameters presented the highest performance as an alternative method to predict the WQIs. For example, the calibration (Val.) and the validation (Val.) models performed best in assessing the WQIs with R2 (0.99) and with R2 (0.97–0.99), respectively. Finally, a combination of WQIs, CA, PCA, and SVMR approaches could be employed to assess surface water quality in Qaroun Lake. Full article
(This article belongs to the Section Water Quality and Contamination)
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26 pages, 5190 KiB  
Article
Multi-Step Calibration Approach for SWAT Model Using Soil Moisture and Crop Yields in a Small Agricultural Catchment
by Francis Kilundu Musyoka, Peter Strauss, Guangju Zhao, Raghavan Srinivasan and Andreas Klik
Water 2021, 13(16), 2238; https://doi.org/10.3390/w13162238 - 17 Aug 2021
Cited by 25 | Viewed by 5666
Abstract
The quantitative prediction of hydrological components through hydrological models could serve as a basis for developing better land and water management policies. This study provides a comprehensive step by step modelling approach for a small agricultural watershed using the SWAT model. The watershed [...] Read more.
The quantitative prediction of hydrological components through hydrological models could serve as a basis for developing better land and water management policies. This study provides a comprehensive step by step modelling approach for a small agricultural watershed using the SWAT model. The watershed is situated in Petzenkirchen in the western part of Lower Austria and has total area of 66 hectares. At present, 87% of the catchment area is arable land, 5% is used as pasture, 6% is forested and 2% is paved. The calibration approach involves a sequential calibration of the model starting from surface runoff, and groundwater flow, followed by crop yields and then soil moisture, and finally total streamflow and sediment yields. Calibration and validation are carried out using the r-package SWATplusR. The impact of each calibration step on sediment yields and total streamflow is evaluated. The results of this approach are compared with those of the conventional model calibration approach, where all the parameters governing various hydrological processes are calibrated simultaneously. Results showed that the model was capable of successfully predicting surface runoff, groundwater flow, soil profile water content, total streamflow and sediment yields with Nash-Sutcliffe efficiency (NSE) of greater than 0.75. Crop yields were also well simulated with a percent bias (PBIAS) ranging from −17% to 14%. Surface runoff calibration had the highest impact on streamflow output, improving NSE from 0.39 to 0.77. The step-wise calibration approach performed better for streamflow prediction than the simultaneous calibration approach. The results of this study show that the step-wise calibration approach is more accurate, and provides a better representation of different hydrological components and processes than the simultaneous calibration approach. Full article
(This article belongs to the Special Issue Modelling of Soil Conservation, Soil Erosion and Sediment Transport)
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17 pages, 3987 KiB  
Article
Reclaimed Water for Vineyard Irrigation in a Mediterranean Context: Life Cycle Environmental Impacts, Life Cycle Costs, and Eco-Efficiency
by Kledja Canaj, Domenico Morrone, Rocco Roma, Francesca Boari, Vito Cantore and Mladen Todorovic
Water 2021, 13(16), 2242; https://doi.org/10.3390/w13162242 - 17 Aug 2021
Cited by 25 | Viewed by 3891
Abstract
The agricultural sector in the Mediterranean region, is increasingly using reclaimed water as an additional source for irrigation. However, there is a limited number of case studies about product-based life cycle analysis to ensure that the overall benefits of reclaimed water do indeed [...] Read more.
The agricultural sector in the Mediterranean region, is increasingly using reclaimed water as an additional source for irrigation. However, there is a limited number of case studies about product-based life cycle analysis to ensure that the overall benefits of reclaimed water do indeed outweigh the impacts. The Life Cycle Assessment (LCA) and Life Cycle Costing (LCC) methods are used in this study to investigate the environmental impacts and costs of vineyard cropping systems when tertiary reclaimed water is used as a supplementary source of irrigation water (integrated system). The conventional production system utilizing 100% groundwater was used as a reference system. As a proxy for sustainability, eco-efficiency, which combines economic and environmental performance, was assessed. The LCA revealed that the integrated system could reduce the net environmental impact by 23.8% due to lower consumption of irrigation water (−50%), electricity (−27.7%), and chemical fertilizers (−22.6%). Nevertheless, trade-offs between economics and the environment occurred as an integrated system is associated with higher life cycle costs and lower economic returns due to lower crop yield (−9.1%). The combined eco-efficiency assessment (ratio of economic value added to total environmental impact) revealed that the integrated system outperformed in terms of eco-efficiency by 12.6% due to lower environmental impacts. These results confirmed that reclaimed water could help to ensure an economically profitable yield with net environmental benefits. Our results provided an up-to-date and consistent life cycle analysis contributing to the creation of a valuable knowledge base for the associated costs and benefits of vineyard cultivation with treated wastewater. Full article
(This article belongs to the Special Issue Climate Smart Irrigation Management for Sustainable Agricultural Cultivation)
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17 pages, 3906 KiB  
Article
Laboratory Analysis of Debris Flow Characteristics and Berm Performance
by Kukhyun Ryou, Hyungjoon Chang and Hojin Lee
Water 2021, 13(16), 2223; https://doi.org/10.3390/w13162223 - 16 Aug 2021
Cited by 3 | Viewed by 3257
Abstract
In this study, laboratory tests were used to determine the deposition characteristics (runout distance, lateral width, and deposition area) of debris flow and their relationships with the flow characteristics (flow velocity and flow depth) according to the presence of a berm. An experimental [...] Read more.
In this study, laboratory tests were used to determine the deposition characteristics (runout distance, lateral width, and deposition area) of debris flow and their relationships with the flow characteristics (flow velocity and flow depth) according to the presence of a berm. An experimental flume 1.3 to 1.9 m long, 0.15 m wide, and 0.3 m high was employed to investigate the effects of channel slope and volumetric concentration of sediment with and without the berm. The runout distance (0.201–1.423 m), lateral width (0.045–0.519 m), and deposition area (0.008–0.519 m2) increased as the channel slope increased and as the volumetric concentration of sediment decreased. These quantities also increased with the flow velocity and flow depth. In addition, the maximum reductions in the runout distance, lateral width, and deposition area were 69.1%, 65.9%, and 93%, respectively, upon berm installation. The results of this study illustrate general debris flow characteristics according to berm installation; the reported relationship magnitudes are specific to the experimental conditions described herein. However, the results of this study contribute to the design of site-specific berms in the future by providing data describing the utility and function of berms in mitigating debris flow. Full article
(This article belongs to the Special Issue Mechanism and Prevention of Debris Flow Disaster)
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14 pages, 1889 KiB  
Article
Do Single-Component and Mixtures Selected Organic UV Filters Induce Embryotoxic Effects in Zebrafish (Danio rerio)?
by Jana Cahova, Jana Blahova, Lucie Plhalova, Zdenka Svobodova and Caterina Faggio
Water 2021, 13(16), 2203; https://doi.org/10.3390/w13162203 - 13 Aug 2021
Cited by 35 | Viewed by 3619
Abstract
UVs are important ingredients in common cosmetic products (e.g., sunscreens, hairsprays, soap). After their use, they can enter the aquatic ecosystem and negatively affect non-target aquatic organisms. The aim of our study was to evaluate acute embryotoxicity of selected organic UVs 2-phenylbenzimidazole-5-sulfonic acid [...] Read more.
UVs are important ingredients in common cosmetic products (e.g., sunscreens, hairsprays, soap). After their use, they can enter the aquatic ecosystem and negatively affect non-target aquatic organisms. The aim of our study was to evaluate acute embryotoxicity of selected organic UVs 2-phenylbenzimidazole-5-sulfonic acid (PBSA), ethylhexyl methoxycinnamate (EHMC), octocrylene (OC), 4-methylbenzylidene camphor (4-MBC) and benzophenone-3 (BP-3). The chemicals were tested both as a single substance and their mixtures. The types of mixtures were chosen as follows: the combination of OC and 4-MBC; the combination of PBSA, EHMC and BP-3 and the combination of all five UV filters. The embryotoxicity was evaluated using a modified method of the Fish Embryo Acute Toxicity Test-OECD guideline 236 and zebrafish (Danio rerio) was selected as a suitable fish model organism. The toxic effects were studied by assessing mortality, hatching and the occurrence of malformations at 24, 48, 72 and 96 h post fertilization. The obtained results indicate that especially the mixture of OC and 4-MBC presents a potential risk of embryotoxicity for zebrafish due to a significant increase in mortality, which was 41.7% in the experimental group exposed to 10 μg/L at 96 h post fertilization. Based on our results, the most effected sub-lethal endpoints were hatching and malformation (e.g., edema of pericard, bent spine, yolk edema), but with no statistically significant effect. These results differ within groups with single UVs and with their mixtures, suggesting the interaction of these substances when they are exposed together. Full article
(This article belongs to the Special Issue Aquatic Ecotoxicity Assessment)
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15 pages, 5188 KiB  
Article
Synthesis and Characterization of Sr-Doped ZnSe Nanoparticles for Catalytic and Biological Activities
by V. Beena, S. L. Rayar, S. Ajitha, Awais Ahmad, Munirah D. Albaqami, Fatmah Ahmed Ali Alsabar and Mika Sillanpää
Water 2021, 13(16), 2189; https://doi.org/10.3390/w13162189 - 11 Aug 2021
Cited by 26 | Viewed by 3996
Abstract
The development of cost-effective and ecofriendly approaches toward water purification and antibacterial activity is a hot research topic in this era. Purposely, strontium-doped zinc selenide (Sr-doped ZnSe) nanoparticles, with different molar ratios of Sr2+ cations (0.01, 0.05, and 0.1), were prepared via [...] Read more.
The development of cost-effective and ecofriendly approaches toward water purification and antibacterial activity is a hot research topic in this era. Purposely, strontium-doped zinc selenide (Sr-doped ZnSe) nanoparticles, with different molar ratios of Sr2+ cations (0.01, 0.05, and 0.1), were prepared via the co-precipitation method, in which sodium borohydride (NaBH4) and 2-mercaptoethanol were employed as reducing and stabilizing agents, respectively. The ZnSe cubic structure expanded by Sr2+ cations was indicated by X-ray diffraction (XRD) analysis. The absorption of the chemical compounds on the surface was observed via Fourier transform infrared (FT-IR) spectroscopy. The optical orientation was measured by ultraviolet–visible diffused reflectance spectroscopy (UV-DRS) analysis. The surface area, morphology, and elemental purity were analyzed using field emission scanning electron microscopy (FE-SEM), high-resolution transmission electron microscopy (HR-TEM), and energy-dispersive spectroscopy (EDS) analyses. The oxidation state and valency of the synthesized nanoparticles were analyzed using X-ray photoelectron spectroscopy (XPS). Sr-doped ZnSe nanoparticles were investigated for photocatalytic degradation of methyl orange (MO), and their antibacterial potential was investigated against different bacterial strains. The antibacterial activity examined against Staphylococcus aureus and Escherichia coli implied the excellent biological activity of the nanoparticles. Moreover, the Sr-doped ZnSe nanoparticles were evaluated by the successful degradation of methyl orange under visible light irradiation. Therefore, Sr-doped ZnSe nanoparticles have tremendous potential in biological and water remediation fields. Full article
(This article belongs to the Special Issue Advanced Materials and Technologies for Pollution Detection and Environmental Remediation)
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34 pages, 3097 KiB  
Article
Closing Water Cycles in the Built Environment through Nature-Based Solutions: The Contribution of Vertical Greening Systems and Green Roofs
by David Pearlmutter, Bernhard Pucher, Cristina S. C. Calheiros, Karin A. Hoffmann, Andreas Aicher, Pedro Pinho, Alessandro Stracqualursi, Alisa Korolova, Alma Pobric, Ana Galvão, Ayça Tokuç, Bilge Bas, Dimitra Theochari, Dragan Milosevic, Emanuela Giancola, Gaetano Bertino, Joana A. C. Castellar, Julia Flaszynska, Makbulenur Onur, Mari Carmen Garcia Mateo, Maria Beatrice Andreucci, Maria Milousi, Mariana Fonseca, Sara Di Lonardo, Veronika Gezik, Ulrike Pitha and Thomas Nehlsadd Show full author list remove Hide full author list
Water 2021, 13(16), 2165; https://doi.org/10.3390/w13162165 - 6 Aug 2021
Cited by 40 | Viewed by 11832
Abstract
Water in the city is typically exploited in a linear process, in which most of it is polluted, treated, and discharged; during this process, valuable nutrients are lost in the treatment process instead of being cycled back and used in urban agriculture or [...] Read more.
Water in the city is typically exploited in a linear process, in which most of it is polluted, treated, and discharged; during this process, valuable nutrients are lost in the treatment process instead of being cycled back and used in urban agriculture or green space. The purpose of this paper is to advance a new paradigm to close water cycles in cities via the implementation of nature-based solutions units (NBS_u), with a particular focus on building greening elements, such as green roofs (GRs) and vertical greening systems (VGS). The hypothesis is that such “circular systems” can provide substantial ecosystem services and minimize environmental degradation. Our method is twofold: we first examine these systems from a life-cycle point of view, assessing not only the inputs of conventional and alternative materials, but the ongoing input of water that is required for irrigation. Secondly, the evapotranspiration performance of VGS in Copenhagen, Berlin, Lisbon, Rome, Istanbul, and Tel Aviv, cities with different climatic, architectural, and sociocultural contexts have been simulated using a verticalized ET0 approach, assessing rainwater runoff and greywater as irrigation resources. The water cycling performance of VGS in the mentioned cities would be sufficient at recycling 44% (Lisbon) to 100% (Berlin, Istanbul) of all accruing rainwater roof–runoff, if water shortages in dry months are bridged by greywater. Then, 27–53% of the greywater accruing in a building could be managed on its greened surface. In conclusion, we address the gaps in the current knowledge and policies identified in the different stages of analyses, such as the lack of comprehensive life cycle assessment studies that quantify the complete “water footprint” of building greening systems. Full article
(This article belongs to the Special Issue Water and Circular Cities)
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30 pages, 4992 KiB  
Article
Hydrochemical Characterisation of High-Fluoride Groundwater and Development of a Conceptual Groundwater Flow Model Using a Combined Hydrogeological and Hydrochemical Approach on an Active Volcano: Mount Meru, Northern Tanzania
by George Bennett, Jill Van Reybrouck, Ceven Shemsanga, Mary Kisaka, Ines Tomašek, Karen Fontijn, Matthieu Kervyn and Kristine Walraevens
Water 2021, 13(16), 2159; https://doi.org/10.3390/w13162159 - 6 Aug 2021
Cited by 17 | Viewed by 3603
Abstract
This study characterises high-fluoride groundwater in the aquifer system on the flanks of Mount Meru, focusing on parts of the flanks that were only partially or not at all covered by previous research. Additionally, we analyse the impact of rainwater recharge on groundwater [...] Read more.
This study characterises high-fluoride groundwater in the aquifer system on the flanks of Mount Meru, focusing on parts of the flanks that were only partially or not at all covered by previous research. Additionally, we analyse the impact of rainwater recharge on groundwater chemistry by monitoring spring discharges during water sampling. The results show that the main groundwater type in the study area is NaHCO3 alkaline groundwater (average pH = 7.8). High F− values were recorded: in 175 groundwater samples, the concentrations range from 0.15 to 301 mg/L (mean: 21.89 mg/L, median: 9.67 mg/L), with 91% of the samples containing F− values above the WHO health-based guideline for drinking water (1.5 mg/L), whereas 39% of the samples have Na+ concentrations above the WHO taste-based guideline of 200 mg/L. The temporal variability in F− concentrations between different seasons is due to the impact of the local groundwater recharge. We recommend that a detailed ecohydrological study should be carried out for the low-fluoride springs from the high-altitude recharge areas on the eastern and northwestern flanks of Mount Meru inside Arusha National Park. These springs are extracted for drinking purposes. An ecohydrological study is required for the management of these springs and their potential enhanced exploitation to ensure the sustainability of this water extraction practice. Another strategy for obtaining safe drinking water could be to use a large-scale filtering system to remove F− from the groundwater. Full article
(This article belongs to the Special Issue Groundwater Resources Management: Reconciling Demand, High Quality Resources and Sustainability)
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18 pages, 3120 KiB  
Article
Classification of Aquifer Vulnerability by Using the DRASTIC Index and Geo-Electrical Techniques
by Syed Hassan Iqbal Ahmad Shah, Jianguo Yan, Israr Ullah, Bilal Aslam, Aqil Tariq, Lili Zhang and Faisal Mumtaz
Water 2021, 13(16), 2144; https://doi.org/10.3390/w13162144 - 4 Aug 2021
Cited by 32 | Viewed by 5024
Abstract
Vulnerability analysis in areas vulnerable to anthropogenic pollution has become a key element of sensible resource management and land use planning. This study is intended to estimate aquifer vulnerability using the DRASTIC model and using the vertical electrical sounding (VES) and electrical conductivity [...] Read more.
Vulnerability analysis in areas vulnerable to anthropogenic pollution has become a key element of sensible resource management and land use planning. This study is intended to estimate aquifer vulnerability using the DRASTIC model and using the vertical electrical sounding (VES) and electrical conductivity (EC) outcomes. The model allows for the identification of hydrogeological environments within the scope of the research, based on a composite definition of each environment’s main geological, geoelectrical, and hydrogeological factors. The results from the DRASTIC model were divided into four equal intervals, high, medium, low, and very low drastic index values. The SW area and NE area depict drastic index values from medium to very high, making it the most vulnerable zone in the study area, while the NW and SW areas show low to very low drastic index values. In addition, the results from the VES and EC the freshwater aquifer in the NE area and brackish water in the SE area, while the rest of the area falls into the category of brackish water. Overall, it can be concluded that areas having freshwater assemblages are on the verge of becoming contaminated in the future while the rest of the NW and SW areas constitute less vulnerable zones. The validation conducted for DRASTIC and EC shows a nearly positive correlation. Wastewater treatment policies must be developed throughout the studied region to prevent contamination of the remaining groundwater. Full article
(This article belongs to the Special Issue Protection and Usage of Groundwater)
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33 pages, 3939 KiB  
Article
Supporting Restoration Decisions through Integration of Tree-Ring and Modeling Data: Reconstructing Flow and Salinity in the San Francisco Estuary over the Past Millennium
by Paul H. Hutton, David M. Meko and Sujoy B. Roy
Water 2021, 13(15), 2139; https://doi.org/10.3390/w13152139 - 3 Aug 2021
Cited by 4 | Viewed by 3160
Abstract
This work presents updated reconstructions of watershed runoff to San Francisco Estuary from tree-ring data to AD 903, coupled with models relating runoff to freshwater flow to the estuary and salinity intrusion. We characterize pre-development freshwater flow and salinity conditions in the estuary [...] Read more.
This work presents updated reconstructions of watershed runoff to San Francisco Estuary from tree-ring data to AD 903, coupled with models relating runoff to freshwater flow to the estuary and salinity intrusion. We characterize pre-development freshwater flow and salinity conditions in the estuary over the past millennium and compare this characterization with contemporary conditions to better understand the magnitude and seasonality of changes over this time. This work shows that the instrumented flow record spans the range of runoff patterns over the past millennium (averaged over 5, 10, 20 and 100 years), and thus serves as a reasonable basis for planning-level evaluations of historical hydrologic conditions in the estuary. Over annual timescales we show that, although median freshwater flow to the estuary has not changed significantly, it has been more variable over the past century compared to pre-development flow conditions. We further show that the contemporary period is generally associated with greater spring salinity intrusion and lesser summer–fall salinity intrusion relative to the pre-development period. Thus, salinity intrusion in summer and fall months was a common occurrence under pre-development conditions and has been moderated in the contemporary period due to the operations of upstream reservoirs, which were designed to hold winter and spring runoff for release in summer and fall. This work also confirms a dramatic decadal-scale hydrologic shift in the watershed from very wet to very dry conditions during the late 19th and early 20th centuries; while not unprecedented, these shifts have been seen only a few times in the past millennium. This shift resulted in an increase in salinity intrusion in the first three decades of the 20th century, as documented through early records. Population growth and extensive watershed modification during this period exacerbated this underlying hydrologic shift. Putting this shift in the context of other anthropogenic drivers is important in understanding the historical response of the estuary and in setting salinity targets for estuarine restoration. By characterizing the long-term behavior of San Francisco Estuary, this work supports decision-making in the State of California related to flow and salinity management for restoration of the estuarine ecosystem. Full article
(This article belongs to the Special Issue Decision Support Tools for Water Quality Management)
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13 pages, 2017 KiB  
Article
Activated Ailanthus altissima Sawdust as Adsorbent for Removal of Acid Yellow 29 from Wastewater: Kinetics Approach
by Najeeb ur Rahman, Ihsan Ullah, Sultan Alam, Muhammad Sufaid Khan, Luqman Ali Shah, Ivar Zekker, Juris Burlakovs, Anna Kallistova, Nikolai Pimenov, Zane Vincevica-Gaile, Yahya Jani and Mohammad Zahoor
Water 2021, 13(15), 2136; https://doi.org/10.3390/w13152136 - 3 Aug 2021
Cited by 42 | Viewed by 3133
Abstract
In this study, Ailanthus altissima sawdust was chemically activated and characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Energy Dispersive X rays (EDX), and surface area analyzer. The sawdust was used as an adsorbent for the removal of azo dye; Acid [...] Read more.
In this study, Ailanthus altissima sawdust was chemically activated and characterized by Scanning Electron Microscopy (SEM), Fourier Transform Infrared (FTIR), Energy Dispersive X rays (EDX), and surface area analyzer. The sawdust was used as an adsorbent for the removal of azo dye; Acid Yellow 29 (AY 29) from wastewater. Different kinetic and equilibrium models were used to calculate the adsorption parameters. Among the applied models, the more suitable model was Freundlich with maximum adsorption capacities of 9.464, 12.798, and 11.46 mg/g at 20 °C, 30 °C, and 40 °C respectively while R2 values close to 1. Moreover, the kinetic data was best fitted in pseudo second order kinetic model with high R2 values approaching to 1. Furthermore, adsorption thermodynamics parameters such as free energy, enthalpy, and entropy were calculated and the adsorption process was found to be exothermic with a value of ∆H° = −9.981 KJ mol−1, spontaneous that was concluded from ΔG° values which were negative (−0.275, −3.422, and −6.171 KJ mol−1 at 20, 30, and 40 °C respectively). A positive entropy change ∆S° with a value of 0.0363 KJ mol−1 indicated the increase disorder during adsorption process. It was concluded that the activated sawdust could be used as a suitable adsorbent for the removal of waste material, especially dyes from polluted waters. Full article
(This article belongs to the Special Issue Efficient Catalytic and Microbial Treatment of Water Pollutants)
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17 pages, 2812 KiB  
Article
Seed Halo-Priming Improves Seedling Vigor, Grain Yield, and Water Use Efficiency of Maize under Varying Irrigation Regimes
by AbdAllah M. El-Sanatawy, Salwa M.A.I. Ash-Shormillesy, Naglaa Qabil, Mohamed F. Awad and Elsayed Mansour
Water 2021, 13(15), 2115; https://doi.org/10.3390/w13152115 - 31 Jul 2021
Cited by 35 | Viewed by 5386
Abstract
Water-deficit stress poses tremendous constraints to sustainable agriculture, particularly under abrupt climate change. Hence, it is crucial to find eco-friendly approaches to ameliorate drought tolerance, especially for sensitive crops such as maize. This study aimed at assessing the impact of seed halo-priming on [...] Read more.
Water-deficit stress poses tremendous constraints to sustainable agriculture, particularly under abrupt climate change. Hence, it is crucial to find eco-friendly approaches to ameliorate drought tolerance, especially for sensitive crops such as maize. This study aimed at assessing the impact of seed halo-priming on seedling vigor, grain yield, and water use efficiency of maize under various irrigation regimes. Laboratory trials evaluated the influence of seed halo-priming using two concentrations of sodium chloride solution, 4000 and 8000 ppm NaCl, versus unprimed seeds on seed germination and seedling vigor parameters. Field trials investigated the impact of halo-priming treatments on maize yield and water use efficiency (WUE) under four irrigation regimes comprising excessive (120% of estimated crop evapotranspiration, ETc), normal (100% ETc), and deficit (80 and 60% ETc) irrigation regimes. Over-irrigation by 20% did not produce significantly more grain yield but considerably reduced WUE. Deficit irrigation (80 and 60%ETc) gradually reduced grain yield and its attributes. Halo-priming treatments, particularly 4000 ppm NaCl, improved uniformity and germination speed, increased germination percentage and germination index, and produced more vigorous seedlings with heavier dry weight compared with unprimed seeds. Under field conditions, the plants originated from halo-primed seeds, especially with 4000 ppm NaCl, had higher grain yield and WUE compared with unprimed seeds under deficit irrigation regimes. The long-lasting stress memory induced by seed halo-priming, particularly with 4000 ppm NaCl, promoted maize seedling establishment, grain yield, and WUE and consequently mitigated the devastating impacts of drought stress. Full article
(This article belongs to the Section Water, Agriculture and Aquaculture)
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16 pages, 5061 KiB  
Article
Scour Features at Wood Bundles
by Simone Pagliara, Deep Roy and Michele Palermo
Water 2021, 13(15), 2118; https://doi.org/10.3390/w13152118 - 31 Jul 2021
Cited by 2 | Viewed by 2140
Abstract
Structures like blunt-nosed chevrons, log deflectors and double-winged log frames help in modifying the flow regime in the channel by concentrating the flow and increasing navigability. Moreover, they create scour pools in the downstream stilling basin, which can be used either as fish [...] Read more.
Structures like blunt-nosed chevrons, log deflectors and double-winged log frames help in modifying the flow regime in the channel by concentrating the flow and increasing navigability. Moreover, they create scour pools in the downstream stilling basin, which can be used either as fish refuge or as an in-stream storage site for previously dredged material. In this respect, the use of wood debris in the channel in the form of wood bundles has gained attention for the ability of these structures to integrate into the surrounding fluvial habitat and to divert the flow partially towards the central part of the channel when placed in curves. Considering the absence of studies dealing with wood bundles as a restoration structure, the aim of this paper is to analyse the scour mechanism and equilibrium scour morphology of wood bundles in straight and curved channels. In doing so, a wide range of hydraulic conditions, structure positions and configurations were tested. Thereafter, dimensional analysis was carried out to derive useful empirical relationships to predict the maximum scour depth and length as well as the maximum dune height based on a novel, equivalent Froude number, which accounts for the effects of channel curvature and structure position. Moreover, the various resulting scour morphology types were classified, and conditions of their existence were determined depending on the abovementioned Froude number and other key hydraulic parameters. Full article
(This article belongs to the Section Water Erosion and Sediment Transport)
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18 pages, 9733 KiB  
Article
Spatiotemporal Hotspots and Decadal Evolution of Extreme Rainfall-Induced Landslides: Case Studies in Southern Taiwan
by Chunhung Wu and Chengyi Lin
Water 2021, 13(15), 2090; https://doi.org/10.3390/w13152090 - 30 Jul 2021
Cited by 11 | Viewed by 2783
Abstract
The 2009 Typhoon Morakot triggered numerous landslides in southern Taiwan, and the landslide ratios in the Ailiao and Tamali river watershed were 7.6% and 10.7%, respectively. The sediment yields from the numerous landslides that were deposited in the gullies and narrow reaches upstream [...] Read more.
The 2009 Typhoon Morakot triggered numerous landslides in southern Taiwan, and the landslide ratios in the Ailiao and Tamali river watershed were 7.6% and 10.7%, respectively. The sediment yields from the numerous landslides that were deposited in the gullies and narrow reaches upstream of Ailiao and Tamali river watersheds dominated the landslide recovery and evolution from 2010 to 2015. Rainfall records and annual landslide inventories from 2005 to 2015 were used to analyze the landslide evolution and identify the landslide hotspots. The landslide recovery time in the Ailiao and Tamali river watershed after 2009 Typhoon Morakot was estimated as 5 years after 2009 Typhoon Morakot. The landslide was easily induced, enlarged, or difficult to recover during the oscillating period, particularly in the sub-watersheds, with a landslide ratio > 4.4%. The return period threshold of rainfall-induced landslides during the landslide recovery period was <2 years, and the landslide types of the new or enlarged landslide were the bank-erosion landslide, headwater landslide, and the reoccurrence of old landslide. The landslide hotspot areas in the Ailiao and Tamali river watershed were 2.67–2.88 times larger after the 2009 Typhoon Morakot using the emerging hot spot analysis, and most of the new or enlarged landslide cases were identified into the oscillating or sporadic or consecutive landslide hotspots. The results can contribute to developing strategies of watershed management in watersheds with a dense landslide. Full article
(This article belongs to the Special Issue Soil–Water Conservation, Erosion, and Landslide)
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28 pages, 8150 KiB  
Article
Impacts of Irrigation Managements on Soil CO2 Emission and Soil CH4 Uptake of Winter Wheat Field in the North China Plain
by Faisal Mehmood, Guangshuai Wang, Yang Gao, Yueping Liang, Muhammad Zain, Shafeeq Ur Rahman and Aiwang Duan
Water 2021, 13(15), 2052; https://doi.org/10.3390/w13152052 - 28 Jul 2021
Cited by 23 | Viewed by 3219
Abstract
The North China Plain is an important irrigated agricultural area in China. However, the effects of irrigation management on carbon emission are not well documented in this region. Due to the uneven seasonal distribution of rainfall, irrigation is mainly concentrated in the winter [...] Read more.
The North China Plain is an important irrigated agricultural area in China. However, the effects of irrigation management on carbon emission are not well documented in this region. Due to the uneven seasonal distribution of rainfall, irrigation is mainly concentrated in the winter wheat growing season in the North China Plain. In this study, we estimated CO2 emission and soil CH4 uptake from winter wheat fields with different irrigation methods and scheduling treatments using the static chamber-gas chromatography method from April to May 2017 and 2018. Treatments included three irrigation methods (surface drip, sprinkler, and border) and three irrigation scheduling levels that initiated as soon as the soil moisture drained to 50%, 60%, and 70% of the field capacity for a 0–100 cm soil profile were tested. The results showed that both the irrigation methods and scheduling significantly influenced (p < 0.05) the cumulative CO2 and CH4 emission, grain yield, global warming potential (GWP), GWP Intensity (GWPI), GWPI per unit irrigation applied, and water use efficiency (WUE). Compared to 60% and 70% FC, 50% FC irrigation scheduling de-creased accumulated CH4 uptake 26.8–30.3% and 17.8–25.4%, and reduced accumulated CO2 emissions 7.0–15.3% and 12.6–19.4%, respectively. Conversely, 50% FC reduced GWP 6.5–13.3% and 12.5–19.4% and lower grain yield 10.4–19.7% and 8.5–16.6% compared to 60% and 70% FC irrigation scheduling in 2017 and 2018, respectively. Compared to sprinkler irrigation and border irrigation, drip irrigation at 60% FC increased the accumulated CH4 uptake 11.3–12.1% and 1.9–5.5%, while reduced the accumulated CO2 emissions from 7.5–8.8% and 10.1–12.1% in 2017 and 2018, respectively. Moreover, drip irrigation at 60% FC increased grain yield 5.2–7.5% and 6.3–6.8%, WUE 0.9–5.4% and 5.7–7.4%, and lowered GWP 8.0–9.8% and 10.1–12.0% compared to sprinkler and border irrigation in 2017 and 2018, respectively. The interaction of irrigation scheduling and irrigation methods significantly impacted accumulated CH4 uptake, cumulative CO2 amount, and GWP in 2018 only while grain yield and WUE in the entire study. Overall, drip irrigation at 60% FC is the optimal choice in terms of higher grain yield, WUE, and mitigating GWP and GWPI from winter wheat fields in North China Plain. Full article
(This article belongs to the Special Issue Measures on Irrigation and Agronomy to Improve Crop Water Use Efficiency)
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22 pages, 2086 KiB  
Article
Causal Relations of Upscaled Urban Aquaponics and the Food-Water-Energy Nexus—A Berlin Case Study
by Gösta F. M. Baganz, Manfred Schrenk, Oliver Körner, Daniela Baganz, Karel J. Keesman, Simon Goddek, Zorina Siscan, Elias Baganz, Alexandra Doernberg, Hendrik Monsees, Thomas Nehls, Werner Kloas and Frank Lohrberg
Water 2021, 13(15), 2029; https://doi.org/10.3390/w13152029 - 24 Jul 2021
Cited by 13 | Viewed by 7208
Abstract
Aquaponics, the water-reusing production of fish and crops, is taken as an example to investigate the consequences of upscaling a nature-based solution in a circular city. We developed an upscaled-aquaponic scenario for the German metropolis of Berlin, analysed the impacts, and studied the [...] Read more.
Aquaponics, the water-reusing production of fish and crops, is taken as an example to investigate the consequences of upscaling a nature-based solution in a circular city. We developed an upscaled-aquaponic scenario for the German metropolis of Berlin, analysed the impacts, and studied the system dynamics. To meet the annual fish, tomato, and lettuce demand of Berlin’s 3.77 million residents would require approximately 370 aquaponic facilities covering a total area of 224 hectares and the use of different combinations of fish and crops: catfish/tomato (56%), catfish/lettuce (13%), and tilapia/tomato (31%). As a predominant effect, in terms of water, aquaponic production would save about 2.0 million m3 of water compared to the baseline. On the supply-side, we identified significant causal link chains concerning the Food-Water-Energy nexus at the aquaponic facility level as well as causal relations of a production relocation to Berlin. On the demand-side, a ‘freshwater pescatarian diet’ is discussed. The new and comprehensive findings at different system levels require further investigations on this topic. Upscaled aquaponics can produce a relevant contribution to Berlin’s sustainability and to implement it, research is needed to find suitable sites for local aquaponics in Berlin, possibly inside buildings, on urban roofscape, or in peri-urban areas. Full article
(This article belongs to the Special Issue Water and Circular Cities)
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25 pages, 7787 KiB  
Article
A Spatially Explicit Crop Yield Model to Simulate Agricultural Productivity for Past Societies under Changing Environmental Conditions
by Maarten Van Loo and Gert Verstraeten
Water 2021, 13(15), 2023; https://doi.org/10.3390/w13152023 - 24 Jul 2021
Cited by 4 | Viewed by 2955
Abstract
Most contemporary crop yield models focus on a small time window, operate on a plot location, or do not include the effects of the changing environment, which makes it difficult to use these models to assess the agricultural sustainability for past societies. In [...] Read more.
Most contemporary crop yield models focus on a small time window, operate on a plot location, or do not include the effects of the changing environment, which makes it difficult to use these models to assess the agricultural sustainability for past societies. In this study, adaptions were made to the agronomic AquaCrop model. This adapted model was ran to cover the last 4000 years to simulate the impact of climate and land cover changes, as well as soil dynamics, on the productivity of winter wheat crops for a Mediterranean mountain environment in SW Turkey. AquaCrop has been made spatially explicit, which allows hydrological interactions between different landscape positions, whilst computational time is kept limited by implementing parallelisation schemes on a supercomputer. The adapted model was calibrated and validated using crop and soil information sampled during the 2015 and 2016 harvest periods. Simulated crop yields for the last 4000 years show the strong control of precipitation, while changes in soil thickness following erosion, and to lesser extent re-infiltration of runoff along a slope catena also have a significant impact on crop yield. The latter is especially important in the valleys, where soil and water accumulate. The model results also show that water export to the central valley strongly increased (up to four times) following deforestation and the resulting soil erosion on the hillslopes, turning it into a marsh and rendering it unsuitable for crop cultivation. Full article
(This article belongs to the Section Water, Agriculture and Aquaculture)
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20 pages, 1537 KiB  
Article
Towards Regional Scale Stormwater Flood Management Strategies through Rapid Preliminary Intervention Screening
by James L. Webber, Mariano Balbi, David Lallemant, Michael J. Gibson, Guangtao Fu, David Butler and Perrine Hamel
Water 2021, 13(15), 2027; https://doi.org/10.3390/w13152027 - 24 Jul 2021
Cited by 7 | Viewed by 4558
Abstract
This paper presents the advantages and opportunities for rapid preliminary intervention screening to enhance inclusion of green infrastructures in regional scale stormwater management. Stormwater flooding is widely recognised as a significant and worsening natural hazard across the globe; however, current management approaches aimed [...] Read more.
This paper presents the advantages and opportunities for rapid preliminary intervention screening to enhance inclusion of green infrastructures in regional scale stormwater management. Stormwater flooding is widely recognised as a significant and worsening natural hazard across the globe; however, current management approaches aimed at the site scale do not adequately explore opportunities for integrated management at the regional scale at which decisions are made. This research addresses this gap through supporting the development of stormwater management strategies, including green infrastructure, at a regional scale. This is achieved through upscaling a modelling approach using a spatially explicit inundation model (CADDIES) coupled with an economic model of inundation loss (OpenProFIA) to support widescale evaluation of green infrastructure during the informative early-stage development of stormwater management strategies. This novel regional scale approach is demonstrated across a case study of the San Francisco Bay Area, spanning 8300 sq km. The main opportunity from this regional approach is to identify spatial and temporal trends which are used to inform regional planning and direct future detailed modelling efforts. The study highlights several limitations of the new method, suggesting it should be applied as part of a suite of landscape management approaches; however, highlights that it has the potential to complement existing stormwater management toolkits. Full article
(This article belongs to the Special Issue The Scale Effects of Green Infrastructures on Urban Stormwater Runoff)
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