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1. Extrapolation of Leaf Measurements to Obtain the Whole-Canopy Transpiration of C<sub>3</sub> and C<sub>4</sub> Xerophytic Shrubs

Author:
Jin, Yanxia; Wang, Xinping; Zhang, Yafeng; Pan, Yanxia; Hu, Rui
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
C3 plants; C4 plants; Reaumuria soongorica; Salsola passerina; air temperature; arithmetics; canopy; ecosystems; field experimentation; gas exchange; growing season; leaf area; leaves; lysimeters; net radiation; photosynthesis; population characteristics; shrubs; stomatal conductance; vapor pressure deficit; vegetation; China
Abstract:
... Quantifying the water balance within areas with sparse vegetation requires frequent measurement of transpiration in water-limited, arid, desert ecosystems. Field experiments were conducted in Shapotou, northwestern China, to examine the feasibility of up-scaling the transpiration of C3 and C4 xerophytic shrubs (Reaumuria soongorica and Salsola passerina, respectively) from th ...
DOI:
10.3390/w10060813

2. Parameter Estimation for Soil Water Retention Curve Using the Salp Swarm Algorithm

Author:
Zhang, Jing; Wang, Zhenhua; Luo, Xiong
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
algorithms; models; soil sampling; soil texture; soil water; soil water characteristic; system optimization; water content
Abstract:
... This paper employs an optimization algorithm called the salp swarm algorithm (SSA) for the parameter estimation of the soil water retention curve model. The SSA simulates the behavior of searching for food of the salp swarm and manages to find the optimal solutions for optimization problems. In this paper, parameter estimation of the van Genuchten model based on nine soil samples, covering eight s ...
DOI:
10.3390/w10060815

3. Phosphorus Fluxes from Three Coastal Watersheds under Varied Agriculture Intensities to the Northern Gulf of Mexico

Author:
He, Songjie; Xu, Y. Jun
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
calcium carbonate; coprecipitation; desorption; estuaries; freshwater; inorganic phosphorus; land use; river flow; rivers; saline water; salinity; sediments; stream channels; summer; total phosphorus; total suspended solids; watersheds; Gulf of Mexico
Abstract:
... This study aims to evaluate recent total phosphorus (TP) and dissolved inorganic phosphorus (DIP) transport from three coastal rivers—the Calcasieu, Mermentau, and Vermilion Rivers—that drain watersheds with varied agriculture intensities (21%, 67%, and 61%, respectively) into the northern Gulf of Mexico, one of the world’s largest summer hypoxic zones. The study also examined th ...
DOI:
10.3390/w10060816

4. Reuse and Recycling of Livestock and Municipal Wastewater in Chilean Agriculture: A Preliminary Assessment

Author:
Villamar, Cristina-Alejandra; Vera-Puerto, Ismael; Rivera, Diego; De la Hoz, Felipe
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
animal density; climate change; feeds; food crops; forests; grain crops; grasslands; irrigated farming; issues and policy; livestock; livestock production; long term effects; municipal wastewater; non-food crops; nutrients; physicochemical properties; wastewater treatment; water reuse; water shortages; Chile
Abstract:
... Chile is an agricultural power, but also one of the most vulnerable countries to climate change and water shortage. About 50% of the irrigated agriculture land in Chile is in the central zone, thanks to its agricultural-climatic characteristics that provide an adequate water supply (100–4000 m3/s). However, the vulnerability scenario in this zone is high due to the seasonal availability of w ...
DOI:
10.3390/w10060817

5. The Impacts of Climate Variability and Land Use Change on Streamflow in the Hailiutu River Basin

Author:
Shao, Guangwen; Guan, Yiqing; Zhang, Danrong; Yu, Baikui; Zhu, Jie
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
Soil and Water Assessment Tool model; atmospheric precipitation; basins; climate; data collection; grasses; hydrometeorology; land use change; planning; shrubs; soil water; stream flow; t-test; temperature; time series analysis; water management; watersheds; wind speed; China
Abstract:
... The Hailiutu River basin is a typical semi-arid wind sandy grass shoal watershed in northwest China. Climate and land use have changed significantly during the period 1970–2014. These changes are expected to impact hydrological processes in the basin. The Mann–Kendall (MK) test and sequential t-test analysis of the regime shift method were used to detect the trend and shifts of the hyd ...
DOI:
10.3390/w10060814

6. An Improved Approach for Evapotranspiration Estimation Using Water Balance Equation: Case Study of Yangtze River Basin

Author:
Li, Qiong; Luo, Zhicai; Zhong, Bo; Zhou, Hao
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
algorithms; atmospheric precipitation; case studies; climate; energy flow; equations; evapotranspiration; hydrologic cycle; mathematical models; soil water; subwatersheds; temperature; temporal variation; Yangtze River
Abstract:
... Evapotranspiration (ET) is a critical component of the water cycle, and it plays an important role in global water exchange and energy flow. However, accurate estimation and numerical simulation of regional ET remain difficult. In this work, based on the water balance equation, an improved regional ET estimating approach was developed by using Gravity Recovery and Climate Experiment (GRACE), daily ...
DOI:
10.3390/w10060812

7. End Use Level Water and Energy Interactions: A Large Non-Residential Building Case Study

Author:
Nair, Sudeep; Hashim, Hafiz; Hannon, Louise; Clifford, Eoghan
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
European Union; buildings; carbon; carbon dioxide; case studies; energy; greenhouse gas emissions; heat; models; residential housing; solar energy; water conservation
Abstract:
... Within the European Union, buildings account for around 40% of the energy use and 36% of CO2 emissions, thus representing a significant challenge in the context of recent EU directives that require all new buildings to be nearly zero-energy by 2020. Reduced consumption of water, and hot water in particular, provides a significant opportunity to reduce energy consumption. While there hav ...
DOI:
10.3390/w10060810

8. Improving the Muskingum Flood Routing Method Using a Hybrid of Particle Swarm Optimization and Bat Algorithm

Author:
Ehteram, Mohammad; Binti Othman, Faridah; Mundher Yaseen, Zaher; Abdulmohsin Afan, Haitham; Falah Allawi, Mohammed; Bt. Abdul Malek, Marlinda; Najah Ahmed, Ali; Shahid, Shamsuddin; P. Singh, Vijay; El-Shafie, Ahmed
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
algorithms; case studies; decision making; disasters; equations; floods; hydrologic models; prediction; water resources; United Kingdom; United States
Abstract:
... Flood prediction and control are among the major tools for decision makers and water resources planners to avoid flood disasters. The Muskingum model is one of the most widely used methods for flood routing prediction. The Muskingum model contains four parameters that must be determined for accurate flood routing. In this context, an optimization process that self-searches for the optimal values o ...
DOI:
10.3390/w10060807

9. Multi-Source Uncertainty Analysis in Simulating Floodplain Inundation under Climate Change

Author:
Maier, Nadine; Breuer, Lutz; Chamorro, Alejandro; Kraft, Philipp; Houska, Tobias
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
General Circulation Models; climate; climate change; ecosystems; floodplains; habitats; hydrology; parameter uncertainty; uncertainty analysis; Germany; Rhine River
Abstract:
... Floodplains are highly complex and dynamic systems in terms of their hydrology. Thus, they harbor highly specialized floodplain plant species depending on different inundation characteristics. Climate change will most likely alter those characteristics. This study investigates the potential impact of climate change on the inundation characteristics of a floodplain of the Rhine River in Hesse, Germ ...
DOI:
10.3390/w10060809

10. Research on Cascade Reservoirs’ Short-Term Optimal Operation under the Effect of Reverse Regulation

Author:
Ji, Changming; Yu, Hongjie; Wu, Jiajie; Yan, Xiaoran; Li, Rui
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
algorithms; hysteresis; models; water flow; water power; water quantity
Abstract:
... Currently research on joint operation of a large reservoir and its re-regulating reservoir focuses on either water quantity regulation or water head regulation. The accuracy of relevant models is in need of improvement if the influence of factors such as water flow hysteresis and the aftereffect of tail water level variation are taken into consideration. In this paper, given the actual production ...
DOI:
10.3390/w10060808

11. Simulation of Fluid and Complex Obstacle Coupling Based on Narrow Band FLIP Method

Author:
Zou, Changjun; Yin, Yong
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
equations; fluid mechanics; mathematical theory; simulation models
Abstract:
... With the continuous development of fluid simulation theory and technology, there are increasingly higher requirements for simulation of complex fluid interaction. Fluid simulation based on the Eulerian method is limited by the grid resolution, and the sawtooth phenomenon occurs near the obstacle boundary. To enhance the fluid interaction performance with complex obstacle, an advanced fluid interac ...
DOI:
10.3390/w10060811

12. Delineation of Suitable Zones for the Application of Managed Aquifer Recharge (MAR) in Coastal Aquifers Using Quantitative Parameters and the Analytical Hierarchy Process

Author:
Kazakis, Nerantzis
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
aquifers; basins; groundwater; hydraulic resistance; surface area; vadose zone; water table; Greece
Abstract:
... Coastal aquifer salinization is usually related to groundwater overexploitation and water table decline. Managed Aquifer Recharge (MAR) can be applied as a measure to reverse and prevent this phenomenon. A detailed literature review was performed to identify the various methods and parameters commonly used to determine suitable sites of MAR application. Based on the review results, a new multi-cri ...
DOI:
10.3390/w10060804

13. Presence of Antibiotic-Resistant <i>Escherichia coli</i> in Wastewater Treatment Plant Effluents Utilized as Water Reuse for Irrigation

Author:
Aslan, Asli; Cole, Zachariah; Bhattacharya, Anunay; Oyibo, Oghenekpaobor
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
Escherichia coli; ampicillin; antibiotic resistance; bacteria; chlorination; ciprofloxacin; disinfection; drugs; effluents; guidelines; irrigation; issues and policy; minimum inhibitory concentration; monitoring; pathogens; rain; sewage; sulfamethoxazole; tetracycline; wastewater treatment; water reuse
Abstract:
... Providing safe water through water reuse is becoming a global necessity. One concern with water reuse is the introduction of unregulated contaminants to the environment that cannot be easily removed by conventional wastewater treatment plants (WWTP). The occurrence of ampicillin, sulfamethoxazole, ciprofloxacin, and tetracycline-resistant Escherichia coli through the treatment stages of a WWTP (ra ...
DOI:
10.3390/w10060805

14. Water Quality Prediction Model of a Water Diversion Project Based on the Improved Artificial Bee Colony–Backpropagation Neural Network

Author:
Chen, Siyu; Fang, Guohua; Huang, Xianfeng; Zhang, Yuhong
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
algorithms; artificial intelligence; models; monitoring; prediction; water pollution; water quality; water supply
Abstract:
... Prediction of water quality which can ensure the water supply and prevent water pollution is essential for a successful water transfer project. In recent years, with the development of artificial intelligence, the backpropagation (BP) neural network has been increasingly applied for the prediction and forecasting field. However, the BP neural network frame cannot satisfy the demand of higher accur ...
DOI:
10.3390/w10060806

15. Effects of the Notch Angle, Notch Length and Injection Rate on Hydraulic Fracturing under True Triaxial Stress: An Experimental Study

Author:
Chen, Yulong; Meng, Qingxiang; Zhang, Jianwei
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
cement; hydraulic fracturing; mathematical theory
Abstract:
... This study focused on the effects of the notch angle, notch length, and injection rate on hydraulic fracturing. True triaxial hydraulic fracturing experiments were conducted with 300 × 300 × 300 mm cement mortar blocks. The test results showed that the fracture initiation pressure decreased as the notch length and injection rate increased, whereas, the fracture initiation pressure decr ...
DOI:
10.3390/w10060801

16. Modeling the Spatial and Seasonal Variations of Groundwater Head in an Urbanized Area under Low Impact Development

Author:
Zheng, Yu; Chen, Sidian; Qin, Huapeng; Jiao, Jiu Jimmy
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
aquifers; case studies; coastal water; drainage; dry season; finite element analysis; groundwater; groundwater flow; groundwater recharge; hydraulic conductivity; land cover; models; risk; runoff; sea level; seasonal variation; stormwater management; streams; subsurface flow; urban areas; urbanization; water conservation; water table; watersheds; wet season; China
Abstract:
... Increasing impervious land cover has great impacts on groundwater regimes in urbanized areas. Low impact development (LID) is generally regarded as a sustainable solution for groundwater conservation. However, the effects of LID on the spatial-temporal distribution of groundwater are not yet fully understood. In this case study, a coupled Storm Water Management Model (SWMM) and Finite Element Subs ...
DOI:
10.3390/w10060803

17. Quantification of Seasonal Precipitation over the upper Chao Phraya River Basin in the Past Fifty Years Based on Monsoon and El Niño/Southern Oscillation Related Climate Indices

Author:
Kinouchi, Tsuyoshi; Yamamoto, Gakuji; Komsai, Atchara; Liengcharernsit, Winai
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
El Nino; basins; climate; data collection; meteorological data; monsoon season; rain; regression analysis; summer; surface temperature; water management; watersheds; Pacific Ocean; Thailand
Abstract:
... For better water resources management, we proposed a method to estimate basin-scale seasonal rainfall over selected areas of the Chao Phraya River Basin, Thailand, from existing climate indices that represent variations in the Asian summer monsoon, the El Niño/Southern Oscillation, and sea surface temperatures (SST) in the Pacific Ocean. The basin-scale seasonal rainfall between 1965 and 20 ...
DOI:
10.3390/w10060800

18. Research on Characteristics of Groundwater Recharge in the Weishan Irrigated District Based on a Bromide Tracer

Author:
Cong, Xin; Xu, Zhenghe; Wang, Tong
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
basins; corn; cotton; groundwater; groundwater recharge; irrigated farming; irrigation management; kriging; surface water; water resources; water table
Abstract:
... Bromide was used as tracer in the Weishan Irrigated District to determine the groundwater recharge as well as to evaluate the impacts of different irrigation basin locations, irrigation regimes, and crop types on the recharge. The comprehensive recharge coefficient and the Kriging Spatial Interpolation methods were used to distinguish the effects of precipitation and surface water irrigation on th ...
DOI:
10.3390/w10060799

19. The Impact of Climate on Hydrological Extremes

Author:
Manfreda, Salvatore; Iacobellis, Vito; Gioia, Andrea; Fiorentino, Mauro; Kochanek, Krzysztof
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
anthropogenic activities; climate change; climatic factors; drought; floods; watersheds
Abstract:
... High and low flows and associated floods and droughts are extreme hydrological phenomena mainly caused by meteorological anomalies and modified by catchment processes and human activities. They exert increasing on human, economic, and natural environmental systems around the world. In this context, global climate change along with local fluctuations may eventually trigger a disproportionate respon ...
DOI:
10.3390/w10060802

20. Disinfection Methods for Swimming Pool Water: Byproduct Formation and Control

Author:
Ilyas, Huma; Masih, Ilyas; van der Hoek, Jan Peter
Source:
Water 2018 v.10 no.6
ISSN:
2073-4441
Subject:
World Health Organization; byproducts; chlorination; chlorine; disinfection; drinking water; electrochemistry; haloacetic acids; hydrogen peroxide; irradiation; oxidants; ozone; swimming pools; toxicity; ultraviolet radiation; water quality
Abstract:
... This paper presents a comprehensive and critical comparison of 10 disinfection methods of swimming pool water: chlorination, electrochemically generated mixed oxidants (EGMO), ultraviolet (UV) irradiation, UV/chlorine, UV/hydrogen peroxide (H2O2), UV/H2O2/chlorine, ozone (O3)/chlorine, O3/H2O2/chlorine, O3 ...
DOI:
10.3390/w10060797