Search

Considering the increasing need for optimal use of water resources, using types of waste water instead of part of the water for making concrete and also reducing the use of potable water in concrete is particularly important, especially in developing countries. Accordingly, this study aimed to investigate and reinforce using greywater as a potential alternative to mixing water in concrete. The specimens' fresh, hardened, and durable properties from 14 concrete mix designs containing six mixing water types, three natural zeolite levels (0, 10, and 20%), and two silica fume levels (0 and 8%) were tested to achieve that. Mixing waters in this study consisted of distilled water, raw greywater, diluted greywater (50% greywater, 50% distilled water), simulations of greywater's salt and organic pollutants, and synthetic greywater. The results showed that raw greywater reduced average compressive strength by 8%, while diluted greywater caused a 1.5% increase instead. Mixing water standards requirements were satisfied on both raw and diluted greywater cases. The results also showed that the impact of greywater on the durability properties of concrete was non-critical in most cases, while diluted greywater, even slightly (4%), improved bulk electrical resistance (RCPT). The test results of synthetic waters showed that reducing chemically active salts and/or organic pollution in greywater can effectively increase the performance of the produced concrete. Using 8% silica fume as cement replacement improved the compressive strength of greywater-made concrete by up to 16% and reduced the cracks and porosity of the specimens based on SEM images. On the other hand, using 20% natural zeolite as cement replacement increased surface (using Wenner probes) and bulk chloride ion penetration by 36 and 78%, respectively. Based on these results, silica fume and natural zeolite replacement are impressive tools to reinforce greywater-made green concrete so that it can properly rival and even replace regular concrete even when using more polluted greywater. Furthermore, these replacements can be great potential alternatives to wastewater dilution or treatments. [ABSTRACT FROM AUTHOR]

Unconventional water includes reclaimed water, harvested rainwater, desalinated seawater, and mine water. Unconventional water use is considered more of a "mandatory responsibility" in China. The initial allocation of unconventional water emphasizes quantity-centered responsibility allocation while the minimum utilization reflects this responsibility. The unconventional water use responsibility (UWUR) should be tailored to the characteristics of each area, moving away from a 'more is better' mindset. However, there is a large research gap in this field. This paper first presented six fundamental principles for unconventional water allocation. Ensuring fairness in allocation involves aligning the allocated amount with urban water usage characteristics. Hence, based on four key features, this paper integrated various socioeconomic and environmental factors to build an initial allocation model. To enhance efficiency, an optimal allocation model was constructed using the zero-sum gains–data envelopment analysis (ZSG-DEA) method. The models were then applied to Jiangsu Province, China, to verify their applicability. The results showed that the projected minimum UWUR allocation (unit: 100 million m3) for each city in 2025 is 1.482 (Nanjing), 1.501 (Wuxi), 0.919 (Xuzhou), 1.029 (Changzhou), 2.977 (Suzhou), 1.497 (Nantong), 0.818 (Lianyungang), 0.766 (Huai'an), 0.875 (Yancheng), 0.920 (Yangzhou), 0.790 (Zhenjiang), 0.858 (Taizhou), and 0.766 (Suqian). The rational and feasible results indicated that the allocation framework proposed in this paper has a certain practicability. Lastly, this paper considered the differences in unconventional water utilization conditions across 13 cities and proposed corresponding measures to improve the utilization. This paper represents a tentative exploration of unconventional water allocation in China and offers theoretical and practical insights for policy-makers to improve territorial spatial planning and sustainable water management. [ABSTRACT FROM AUTHOR]

The development and utilization of unconventional water resources has become a strategy to alleviate the agricultural water crisis in many countries and regions. To understand the research progress, hot spots, and future trends in the field of unconventional water agricultural irrigation (UWAI), this paper systematically analyzes 6738 publications based on the core database of Web of Science 1990–2023 using the scientific bibliometric analysis software CiteSpace, VOSviewer, and Scimago Graphica. The results showed that the research on UWAI is always rapidly developing. Soil science, crop science, and bioengineering are the main disciplines involved. Most research on WUAI has occurred in China and the United States. Countries with higher levels of development tend to have more influence. Collaboration among authors is fragmented, and collaboration between authors and states needs to be strengthened. Through keyword analysis, the research hotspots are summarized as follows: (1) The effects of traditional and emerging pollutants brought by unconventional water irrigation on soil physicochemical properties, crop growth, and groundwater quality; (2) the health threats caused by pollutants entering the food chain and groundwater; (3) unconventional water utilization technologies, including rainwater harvesting agriculture, precision agriculture, and urban agriculture. Future research hotspots will focus on the mechanisms of pollutant solute transport and transformation in the water–soil–crop system under non-conventional water irrigation conditions and crop physiological responses. We suggest that the research on traditional and emerging pollutants in unconventional water should be strengthened in the future, and the risk control system of unconventional water irrigation should be improved. International cooperation should be strengthened, especially with poor countries in arid regions, to promote the formation of unified international standards and guidelines for non-conventional water irrigation in agriculture. [ABSTRACT FROM AUTHOR]

Water supply remains a significant challenge in arid and semi-arid regions, and in addressing this concern, unconventional water sources have gained prominence. Notably, the extraction of water from air humidity, classified as an unconventional water source has seen increased adoption. Diverse techniques have been developed to achieve this goal, with the utilization of mesh networks being particularly prevalent. Consequently, this study assesses the evaluation of the performance of the ERA5 dataset in the simulation of atmospheric variables that influence the ability to assess water harvesting from air humidity (including temperature, wind speed, and water vapor pressure). Also, the possibility of water harvesting from air humidity was investigated in Qazvin Province. The outcomes demonstrated the benefit of incorporating adjustment coefficients in estimating temperature and wind speed using the ERA5 dataset. Based on these findings, the northwestern and southern regions of the province (Kuhin and Takestan) exhibit notable potential during spring and summer for water harvesting from the atmosphere. The peak water harvesting for these stations in the summer is estimated at 10.2 and 9.7 l/day.m2, respectively. Using the ERA5 reanalysis dataset, the annual average potential for water harvesting in the stations was evaluated at 7.9 and 4.6 l/day.m2, respectively. Notably, the minimum water harvesting capacity during the summer season recorded in Qazvin is equal to 3.39 l/day.m2, which can be planned for use in irrigation requirements of green spaces, fields, or gardens.

Water supply remains a significant challenge in arid and semi-arid regions, and in addressing this concern, unconventional water sources have gained prominence. Notably, the extraction of water from air humidity, classified as an unconventional water source has seen increased adoption. Diverse techniques have been developed to achieve this goal, with the utilization of mesh networks being particularly prevalent. Consequently, this study assesses the evaluation of the performance of the ERA5 dataset in the simulation of atmospheric variables that influence the ability to assess water harvesting from air humidity (including temperature, wind speed, and water vapor pressure). Also, the possibility of water harvesting from air humidity was investigated in Qazvin Province. The outcomes demonstrated the benefit of incorporating adjustment coefficients in estimating temperature and wind speed using the ERA5 dataset. Based on these findings, the northwestern and southern regions of the province (Kuhin and Takestan) exhibit notable potential during spring and summer for water harvesting from the atmosphere. The peak water harvesting for these stations in the summer is estimated at 10.2 and 9.7 l/day.m², respectively. Using the ERA5 reanalysis dataset, the annual average potential for water harvesting in the stations was evaluated at 7.9 and 4.6 l/day.m², respectively. Notably, the minimum water harvesting capacity during the summer season recorded in Qazvin is equal to 3.39 l/day.m2, which can be planned for use in irrigation requirements of green spaces, fields, or gardens. [ABSTRACT FROM AUTHOR]

The solar‐driven interfacial evaporation (SIE) technology shows great prospects in seawater desalination and sewage treatment, but it is unable to obtain highly efficient and high‐quality clean nontoxic water at low cost. Here, a novel biodegradable hydrogel‐based solar evaporator (BBH‐L) with a bionic coral structure taking Chinese ink as the solar absorber was developed. This evaporator consists of chitosan/polyvinyl alcohol hydrogel and a loofah substrate. The average evaporation rate and efficiency of BBH‐L reach 4.37 kg/(m2·h) and 98.2%, respectively, under one sun illumination (1 kW/m2), which are attributed to its excellent thermal localization and water transporting abilities. Meanwhile, high salt resistance enables BBH‐L to achieve efficient desalination and purification of other unconventional water. Heavy metal ions in seawater can be effectively removed by chelation and forming hydrogen bonds in hydrogels. This study is anticipated to provide new possibilities to enhance evaporation performance and reduce the costs of water treatment systems. [ABSTRACT FROM AUTHOR]

Unconventional water serves as a bridge to water sustainability. However, many developing nations still have a long way to go in terms of unconventional water utilization. Different regional characteristics lead to different consumption capacities for unconventional water. Consequently, more unconventional water use (UWU) may not necessarily be positive for alleviating water poverty. However, there is a significant research gap in this field. This paper aims to answer three key questions: “Whether UWU consistently alleviates water poverty?” “Is this effect spatially heterogeneous?” and “What role do economic factors play in addressing water poverty?” For that, this paper focused on 30 provinces in China, with the sample period spanning from 2006 to 2021. To identify the mechanisms through which UWU alleviates water poverty, this paper employed a panel fixed-effects model using the Water Poverty Index (WPI) as the dependent variable and the square of UWU amount as an independent variable. The results indicate a non-linear impact of UWU on WPI, with the significance of impact influenced by GDP per capita (PGDP). Furthermore, threshold regressions were conducted with PGDP as the threshold variable. The results revealed a double-threshold effect of PGDP in the impact of UWU on WPI, displaying “U” or inverted “U” shape as PGDP develops: When PGDP is less than or equal to RMB 13,574, UWU demonstrates a negative effect on WPI; when PGDP ranges from RMB 13,574 to RMB 53,653, the effect turns positive; however, when PGDP exceeds RMB 53,653, the effect turns back to negative. The findings confirm that more UWU is not always better. Sustainable utilization plans of water resources must be tailored to local conditions, especially considering the unique characteristics of the regional economy.

Unconventional water includes reclaimed water, harvested rainwater, desalinated seawater, and mine water. Unconventional water use is considered more of a “mandatory responsibility” in China. The initial allocation of unconventional water emphasizes quantity-centered responsibility allocation while the minimum utilization reflects this responsibility. The unconventional water use responsibility (UWUR) should be tailored to the characteristics of each area, moving away from a ‘more is better’ mindset. However, there is a large research gap in this field. This paper first presented six fundamental principles for unconventional water allocation. Ensuring fairness in allocation involves aligning the allocated amount with urban water usage characteristics. Hence, based on four key features, this paper integrated various socioeconomic and environmental factors to build an initial allocation model. To enhance efficiency, an optimal allocation model was constructed using the zero-sum gains–data envelopment analysis (ZSG-DEA) method. The models were then applied to Jiangsu Province, China, to verify their applicability. The results showed that the projected minimum UWUR allocation (unit: 100 million m3) for each city in 2025 is 1.482 (Nanjing), 1.501 (Wuxi), 0.919 (Xuzhou), 1.029 (Changzhou), 2.977 (Suzhou), 1.497 (Nantong), 0.818 (Lianyungang), 0.766 (Huai’an), 0.875 (Yancheng), 0.920 (Yangzhou), 0.790 (Zhenjiang), 0.858 (Taizhou), and 0.766 (Suqian). The rational and feasible results indicated that the allocation framework proposed in this paper has a certain practicability. Lastly, this paper considered the differences in unconventional water utilization conditions across 13 cities and proposed corresponding measures to improve the utilization. This paper represents a tentative exploration of unconventional water allocation in China and offers theoretical and practical insights for policy-makers to improve territorial spatial planning and sustainable water management.

The development and utilization of unconventional water resources has become a strategy to alleviate the agricultural water crisis in many countries and regions. To understand the research progress, hot spots, and future trends in the field of unconventional water agricultural irrigation (UWAI), this paper systematically analyzes 6738 publications based on the core database of Web of Science 1990–2023 using the scientific bibliometric analysis software CiteSpace, VOSviewer, and Scimago Graphica. The results showed that the research on UWAI is always rapidly developing. Soil science, crop science, and bioengineering are the main disciplines involved. Most research on WUAI has occurred in China and the United States. Countries with higher levels of development tend to have more influence. Collaboration among authors is fragmented, and collaboration between authors and states needs to be strengthened. Through keyword analysis, the research hotspots are summarized as follows: (1) The effects of traditional and emerging pollutants brought by unconventional water irrigation on soil physicochemical properties, crop growth, and groundwater quality; (2) the health threats caused by pollutants entering the food chain and groundwater; (3) unconventional water utilization technologies, including rainwater harvesting agriculture, precision agriculture, and urban agriculture. Future research hotspots will focus on the mechanisms of pollutant solute transport and transformation in the water–soil–crop system under non-conventional water irrigation conditions and crop physiological responses. We suggest that the research on traditional and emerging pollutants in unconventional water should be strengthened in the future, and the risk control system of unconventional water irrigation should be improved. International cooperation should be strengthened, especially with poor countries in arid regions, to promote the formation of unified international standards and guidelines for non-conventional water irrigation in agriculture.

The growth of 'unconventional' water resources as a new resource frontier has been much touted over the last two decades and is transforming society’s relationship with water in diverse contexts. Desalination and wastewater reuse, in particular, are increasingly framed together as potentially game-changing technologies for water management and (re)distribution and are carried forward by promises to overcome water scarcity and enhance water security. While there are good reasons to critique the conflation of heterogeneous water resources under the single heading of 'unconventional', we argue that the scale and scope of the transition towards desalination and treated wastewater (which often use similar technologies) merit their inclusion in one Special Issue. The papers presented in this issue advance our understanding of the social, political, economic and cultural dimensions of this water transition. The papers are conceptually and empirically diverse, with case studies across the Global North and Global South. They offer an important counterbalance to the dominant techno-triumphalist narratives that typically surround these technologies, providing unconventional perspectives on unconventional water. In this opening paper, we chart the emergence of unconventional water. We then introduce the papers and highlight the cross-cutting themes of the issue: 1) the (de)politicising discourses that frame desalination and wastewater; 2) the political economies of unconventional water; 3) the materiality and politics of these technologies; and 4) their implications for water justice.

Abstract The solar‐driven interfacial evaporation (SIE) technology shows great prospects in seawater desalination and sewage treatment, but it is unable to obtain highly efficient and high‐quality clean nontoxic water at low cost. Here, a novel biodegradable hydrogel‐based solar evaporator (BBH‐L) with a bionic coral structure taking Chinese ink as the solar absorber was developed. This evaporator consists of chitosan/polyvinyl alcohol hydrogel and a loofah substrate. The average evaporation rate and efficiency of BBH‐L reach 4.37 kg/(m2·h) and 98.2%, respectively, under one sun illumination (1 kW/m2), which are attributed to its excellent thermal localization and water transporting abilities. Meanwhile, high salt resistance enables BBH‐L to achieve efficient desalination and purification of other unconventional water. Heavy metal ions in seawater can be effectively removed by chelation and forming hydrogen bonds in hydrogels. This study is anticipated to provide new possibilities to enhance evaporation performance and reduce the costs of water treatment systems.

This study examines the effects of three irrigation regimes with a combination of saline water and treated wastewater on the accumulation of heavy metals in barley grains. A field experiment was designed as a split‐split plot arrangement in a randomized complete block design, in which treatments were different irrigation regimes (50%, 70%, and 100% full irrigation) and irrigation water types (saline water [SW], treated wastewater [TW], mixed water resources [MWR], and alternative irrigation [AI]). After cultivation and harvesting of the barley crop, the grain yield, 1000‐grain weight, and contents of heavy metals in the grains were measured. The grain yield was enhanced by TW alone, MWR, and AI to 12.8%, 5%, and 9.5% under 70%‐deficit irrigation; and 58.3%, 21.7%, and 8.7% under full irrigation, respectively. Based on the guidelines for safe limits of heavy metals in edible plants and livestock feed, the barley grains were safe for livestock and toxic for humans. The trend of heavy metal contents in the grains was Fe > Zn > Pb > Cu ≥ Cr > Cd. Irrigation with SW compared with TW increased Fe, Cu, Zn, Pb, Cd, and Cr contents in the grains to 11.75%, 10.97%, 5.22%, 19.15%, 3.45%, and 9.21%, respectively. The amounts of toxic elements of Cd and Pb were maximized by using MWR, whereas the Cr content in the grain was maximized by using AI. There were no significant difference in the metal uptake by the grains among all irrigation regimes in any irrigation water resource. However, compared with the other irrigation regimes, the full irrigation resulted in lower Zn, Cu, and Cd contents, whereas the 50%‐deficit irrigation led to lower Pb and Cr contents in the grains. Therefore, irrigation with TW is recommended based on the grain yield, whereas AI is suggested due to lower Cu, Pb, and Cd contents in the grain, and MWR is recommended due to lower Cr content. Furthermore, full and 50%‐deficit irrigation regimes are recommended to, respectively, maximize grain yield and minimize the toxic metal contents in the grain. Practitioner Points: Mixed saline water and treated wastewater and alternative irrigation enhanced grain yield.Saline water versus treated wastewater increased the grain heavy metal contents.Alternative irrigation decreased Fe, Cu, Pb, and Cd amounts in the grain.Grain Cu content had strong relationship with irrigation regime.50%‐deficit irrigation minimized Pb and Cr contents in the grain. [ABSTRACT FROM AUTHOR]

In North China, the shortage of water resources is one of the main restricting factors of agricultural production. In order to alleviate the two problems of agricultural water shortage and mine water discharge and promote the safe utilization of mine water resources. In this paper, the soil column test was used to study the effects of different models of mine water irrigation on the vertical distribution of soil nutrients, salinity and metals. The results show that mine water irrigation can improve soil fertility, and increase the risk of soil and groundwater pollution; mine water irrigation can increase soil salinity, the contents of K+, Na+, Ca2+, Mg2+, Cl- and SO4 2- increased significantly in 0-10 cm and 60-80 cm soil layers, which did not cause soil salinization and alkalization in a short time, and the pH value of soil was not affected by irrigation water quality; mine water irrigation increased the concentrations of Cd and Pb in soil, which accumulated most obviously in 0-20 cm soil layer, which caused soil Cd exceeding the secondary soil environmental standard (Cd = 1.00 mg·kg-1); the mixed irrigation (mine water and clean water) and rotational irrigation could reduce the pollution risk of nitrogen of groundwater, soil salinization, alkalization, Cd and Pb metals. [ABSTRACT FROM AUTHOR]

The growth of 'unconventional' water resources as a new resource frontier has been much touted over the last two decades and is transforming society's relationship with water in diverse contexts. Desalination and wastewater reuse, in particular, are increasingly framed together as potentially game-changing technologies for water management and (re)distribution and are carried forward by promises to overcome water scarcity and enhance water security. While there are good reasons to critique the conflation of heterogeneous water resources under the single heading of 'unconventional', we argue that the scale and scope of the transition towards desalination and treated wastewater (which often use similar technologies) merit their inclusion in one Special Issue. The papers presented in this issue advance our understanding of the social, political, economic and cultural dimensions of this water transition. The papers are conceptually and empirically diverse, with case studies across the Global North and Global South. They offer an important counterbalance to the dominant techno-triumphalist narratives that typically surround these technologies, providing unconventional perspectives on unconventional water. In this opening paper, we chart the emergence of unconventional water. We then introduce the papers and highlight the cross-cutting themes of the issue: 1) the (de)politicising discourses that frame desalination and wastewater; 2) the political economies of unconventional water; 3) the materiality and politics of these technologies; and 4) their implications for water justice. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this study, the Drainmod-S model was used to vary soil salt concentration and the effect of underground drainage on the amount of leaching in a physical model (large lysimeter). A soil extractor was installed at depths of 40, 50, and 70 cm at a distance of 35 cm from the drainage to measure the salinity of the soil solution. In this study, three scenarios were applied including salinity profiles under conventional conditions (mid-season and end-season drainage), soil salinity profiles under different drainage conditions, and prior scenarios with saline irrigation. The second and third scenarios were applied in four drainage stages, respectively. These stages include transplanting and mid-season drainage (days 15 to 20), mid-season drainage (days 35 to 40), mid-season and end-season drainage (days 55 to 60), and end-season drainage (days 75 to 80). The results showed that after simulating the total solute concentration overtime at a depth of 40 cm and comparing it with the measured values, the coefficient of determination (R2) was 0.77 indicating an acceptable Drainmod-S model simulation. This parameter for simulating solute concentration at 50 and 70 cm depth was 0.76 and 0.75, respectively. The mean absolute error parameter (MAE) value was also negligible.

• We developed an integrated adaptive model to determine water allocation. • Multiple factors to assess adaptability between the water allocated and region. • In water emergencies, fairness may need to be compromised to satisfy water demand. • Unconventional water use cannot effectively bridge the supply–demand gap in China. • Improving unconventional water use by over 40% can make up for the water supply. Unconventional water (UW) use has pros and cons, presenting the challenge of matching water utilization with regional water use characteristics. This study proposed the concept of amount-centered adaptive water allocation and built an integrated adaptive allocation model that includes conventional water (CW) and UW adaptability. The model consists of two modules. The first module introduces the regional composite index and inequality index to match CW and UW allocation amount with the sub-region's characteristics. The second module defines the efficiency of CW and UW allocation, employs the Zero-Sum Gains Data Envelopment Analysis to find the solution set with the highest efficiency on the Pareto front, and further modifies it to reach the optimal allocation efficiency. Then the proposed model was applied to Jiangsu Province, China. Empirical and comparative analyses of the 54 weighting plans proved the validity and practicability of the model. The results showed: (1) The model tallies with the principles of fairness and efficiency and reduces the spatial heterogeneity of water shortage risk; (2) When available water supply decreases by over 20% due to future water-related emergency incidents, CW allocation would first reach its upper limit, while UW fails to effectively bridge the supply–demand gap; (3) Only by improving the maximum UW consumption by over 40% can the future risk of extreme water shortages be effectively addressed. The model proposed in this study has excellent practicality and application potential, providing a novel perspective for incorporating UW into the unified management of water resources. [ABSTRACT FROM AUTHOR]

In this study, the Drainmod-S model was used to vary soil salt concentration and the effect of underground drainage on the amount of leaching in a physical model (large lysimeter). A soil extractor was installed at depths of 40, 50, and 70 cm at a distance of 35 cm from the drainage to measure the salinity of the soil solution. In this study, three scenarios were applied including salinity profiles under conventional conditions (mid-season and end-season drainage), soil salinity profiles under different drainage conditions, and prior scenarios with saline irrigation. The second and third scenarios were applied in four drainage stages, respectively. These stages include transplanting and mid-season drainage (days 15 to 20), mid-season drainage (days 35 to 40), mid-season and end-season drainage (days 55 to 60), and end-season drainage (days 75 to 80). The results showed that after simulating the total solute concentration overtime at a depth of 40 cm and comparing it with the measured values, the coefficient of determination (R²) was 0.77 indicating an acceptable Drainmod-S model simulation. This parameter for simulating solute concentration at 50 and 70 cm depth was 0.76 and 0.75, respectively. The mean absolute error parameter (MAE) value was also negligible. [ABSTRACT FROM AUTHOR]

Today, one of the biggest challenges facing the world is the lack of water, especially in the agricultural sector. In this research, we investigated the effects of irrigation method and deficit irrigation with the urban refined effluent on biomass, grain yield, yield components and water use efficiency in single grain crosses 704 maize. This research was carried out in a randomized complete block design with two irrigation systems (furrow irrigation (F) and drip irrigation (T)) and three levels of deficit irrigation treatments of 100 (D1), 75 (D2) and 55 (D3) percent of water requirements in three replications, in 2017, at the collage of Abourihan Research field, University of Tehran, in Pakdasht County. The results showed that the highest yield of biomass was 2.426 Kg m-2 for full drip irrigation treatments; also, there was no significant difference between D1 and D2 treatments. The highest grain yield was 1.240 kg m-2 for the complete drip irrigation treatment. The highest biomass water use efficiency was obtained for the treatment of 75% drip irrigation, which was equal to 5.3 kg per cubic meter of water. Therefore, a drip irrigation system with 75% water requirement is optimal and could be recommended.

Shortage of water resources and renewable per capita in last 30 years is put Iran on crisis threshold. Wastewater reuse is one of the battle solutions for water shortage and prevents wastewater depletion and environmental pollution. Thus, a pilot scale experiment was carried out to evaluate an integrated anaerobic/aerobic treatment for removal of BOD5 and COD, also to reduction of hydraulic retention time by considering optimum removal efficiency. The pilot was an anaerobic/aerobic bioreactor type under continuous-feeding regime based on a central composite design. The pilot was studied in different retention time and aeration was carried out between 5-15 hours. According to different retention times for COD removal efficiency, 24 hours was selected as optimum hydraulic retention time, that it is comparable to those obtained for 48 hours and over in plant roughly and could remove COD and BOD in acceptable ranges, results showed that average removal efficiency for BOD5 were 63.86 and 83.99 percent in aerobic and anaerobic phases, respectively. The average removal efficiency for COD was 76.5 and 74.35 percent for anaerobic and aerobic sections, respectively. The average removal efficiency for BOD5 and COD in this integrated aerobic-anaerobic pilot 95.24 and 94.8 percent, respectively.

The present study was conducted to investigating interaction of three types of mixing water (tap water, briny groundwater and a mixture of their equal ratio), four levels of cement substitution with zeolite in the concrete mix design (0 %, 10 %, 20 % and 30 %), two levels of cement content (250 and 350 kg·m−3) and seven curing ages (3, 7, 28, 56, 90, 180 and 365 days) on compressive strength of concrete. In order to statistical analysis of data - a means that was not employed in the similar studies - the study was designed as a factorial experiment based on the completely randomized design with 168 treatments and three replications (totally 504 concrete specimens). The results of the analysis of variance (ANOVA) showed that neither of the two-, three- and four-way interactions of curing age with other factors were not statistically significant. This means that the gain rate of compressive strength of concrete by time was significantly similar in each possible combination of cement content, water type, and zeolite percentage. However, regarding the significant two- and three-way interactions of other studied factors, more attention should be paid to the results of these interactions than the simple effects of factors. Accordingly, based on the means comparison test (least significant difference: LSD), simultaneous use of unconventional waters with zeolite up to 20 % in the cement content 350 kg·m−3 can be recommended in terms of compressive strength of concrete.

Regarding the significant contribution of the concrete industry in water consumption and greenhouse gas emissions, it is necessary to study the possibility of using unconventional waters and environmental friendly materials in this industry. Accordingly, the present study was conducted to investigate 120 treatments including three levels of water quality (tap water, greywater and mixture of equal ratio of tap water and greywater), four levels of zeolite (0, 10, 20 and 30 percent of zeolite application instead of cement in the concrete mix), two levels of cement content (250 and 350 kg.m-3) and five curing ages (3, 7, 21, 56 and 90 days) in three replications by construction of 360 concrete specimens. Considering the considerable types of the experimental treatments in this study and in respect to the lack of statistical analysis in previous studies, the results of this study were analyzed based on a completely randomized design with factorial experiment using analysis of variance (ANOVA) and means comparison (LSD) tests. The results showed that the use of greywater, in whole or combined, increased the compressive strength of concrete. Also, although the application of zeolite in both cement contents generally reduced the compressive strength of concrete, the rate of change was significantly lesser in cement content 350 kg.m-3 than 250 kg.m-3, so that replacement of 10%, 20% and 30% of cement by zeolite led to decrease of the compressive strength by 15.0%, 26.1% and 34.0%, respectively; whereas in the cement content 350 kg.m-3, the changes of compressive strength of specimens were -2.4%, +5.4% and -13.7%, respectively. However, considering the significant interaction of these two factors with water type, which means the different effects of water quality and the percentage of zeolite on different contents of cement, the best level of application of zeolite and water type regarding the cement content should be selected based on in-situ mix design test.

Morocco, like other the Middle East and North Africa countries, is a water-scarce country confronted with dwindling groundwater reserves, due to climate change impact, and a strong dependence on rain-fed agriculture. Thus, sustainable water resources management is a top priority in the national strategy. Seawater desalination was considered as one of the possible responses to satisfy the water demand of overcrowded coastal towns. The greatest constraints of seawater desalination remain its energy consumption per cubic meter of produced water and the environmental impacts due to the discharge of brines into the natural environment. Despite the many advantages of desalination, its environmental impact, therefore, remains a major concern. Its advantages and drawbacks must be assessed in terms of costs and benefits, societal and environmental aspects, and compared to other freshwater production processes. The objective of this work is twofold. Firstly, the objective is to present thoroughly a bibliographic study on water desalination by highlighting the problems related to energy consumption, fouling and brine management. With an aim to provide an insight on the cost of desalination, this review collates different research studies which evaluate and compare the economic cost of the produced water by three based-membranes processes, nanofiltration, reverse osmosis and electrodialysis, for seawater and brackish water desalination. The second objective meant to review the Moroccan experiences on seawater and brackish water desalination with the technologies used and their operating status. This part of the study is done through synthesis and analysis of expert reports established in the desalination field, which are consulted in the context of the bibliographic research. Finally, this review also focuses on the Moroccan experience in the use of unconventional water for irrigation, with a particular emphasis on the Agadir desalination plant. [ABSTRACT FROM AUTHOR]

The world is going through a health crisis which has triggered an unprecedented economic crisis, according to economists, unprecedented and worrying in its origin, nature, course, and geographic coverage. The confinement of populations, the blocking of logistics chains, the stoppage of economic activity imposed by this COVID-19 health crisis, have highlighted the vulnerability of value chains. Nowadays, the limits of the “just in time” strategy can be observed. To remedy this, it is necessary to understand the characteristics of this economic crisis in its current context. In addition, the pandemic with its effect in prolonged waves caused a more or less severe recession depending on the country, which led to a drop in global energy demand by 6% and an 8% decrease in greenhouse gas emissions. Also, the forecasts are not optimistic for the water sector, which is no exception. Climate change models indicate that precipitation could decrease by more than 20% by 2050. The challenge for Algeria in the years to come is to adapt to a decrease in renewable water resources. The country must mobilize unconventional water resources (desalination and reuse of wastewater) which will be a strategic component in water management. In addition, the development of unconventional resources leads to an increase in electrical energy demand of 12% by year, which must count in the national energy balance. The objective of this work is to offer practical solutions to current energy challenges, defeat the post- COVID-19 energy battle, and face the future water stress that threatens our country. [ABSTRACT FROM AUTHOR]

• Most of China still faces notable water poverty with obvious spatial variations. • Unconventional water use does not always have a positive impact on water poverty. • The impact shows an inverted U-shaped tendency as per capita GDP increases. • Sustainable water management plans should be tailored to local economy. Unconventional water serves as a bridge to water sustainability. However, many developing nations still have a long way to go in terms of unconventional water utilization. Different regional characteristics lead to different consumption capacities for unconventional water. Consequently, more unconventional water use (UWU) may not necessarily be positive for alleviating water poverty. However, there is a significant research gap in this field. This paper aims to answer three key questions: "Whether UWU consistently alleviates water poverty?" "Is this effect spatially heterogeneous?" and "What role do economic factors play in addressing water poverty?" For that, this paper focused on 30 provinces in China, with the sample period spanning from 2006 to 2021. To identify the mechanisms through which UWU alleviates water poverty, this paper employed a panel fixed-effects model using the Water Poverty Index (WPI) as the dependent variable and the square of UWU amount as an independent variable. The results indicate a non-linear impact of UWU on WPI, with the significance of impact influenced by GDP per capita (PGDP). Furthermore, threshold regressions were conducted with PGDP as the threshold variable. The results revealed a double-threshold effect of PGDP in the impact of UWU on WPI, displaying "U" or inverted "U" shape as PGDP develops: When PGDP is less than or equal to RMB 13,574, UWU demonstrates a negative effect on WPI; when PGDP ranges from RMB 13,574 to RMB 53,653, the effect turns positive; however, when PGDP exceeds RMB 53,653, the effect turns back to negative. The findings confirm that more UWU is not always better. Sustainable utilization plans of water resources must be tailored to local conditions, especially considering the unique characteristics of the regional economy. [ABSTRACT FROM AUTHOR]

Water scarcity has threatened the sustainability of human life, ecosystem evolution, and socio-economic development. However, previous studies have often lacked a comprehensive consideration of the impact of water quality and existing solutions, such as inter-basin water transfer and unconventional water resources, on water scarcity. In this paper, an improved approach was proposed to quantify water scarcity levels by comprehensively considering surface water quality and multiple solutions. China's water scarcity was first assessed at a high spatial resolution on a monthly basis over the 5-year period from 2014 to 2018. Then, the driving factors including water quality and solutions were identified by a geographic detector model. Finally, an in-depth investigation was conducted to unravel the effects of water quantity solutions (i.e., inter-basin water transfer and unconventional water use), and water quality solutions (i.e., improving surface water quality) on alleviating water scarcity. Based on monthly assessments considering water quality and multiple existing solutions, the results showed that over half of the national population (∼777 million) faced water scarcity for at least one month of the year. Agricultural water use and inadequate water quality were the main driving factors responsible for China's water scarcity. Over four-fifths of the national population (∼1.10 billion) could benefit from alleviated water scarcity through a combination of water quantity and quality solutions. However, the existing solutions considered were insufficient to completely resolve water scarcity in China, especially in Northern China, persisting as a challenging issue. The results obtained from this study provided a better understanding of China's water scarcity, which could contribute to guiding future efforts aimed at alleviating water scarcity and ensuring water security in China. • Water scarcity assessment incorporated water quality and multiple existing solutions. • China's water scarcity was assessed at a high spatial resolution on a monthly basis. • Over half of the national population faced water scarcity for at least one month of the year. • Agricultural water use and inadequate water quality were the main driving factors. • Over four-fifths of the national population could benefit from alleviated water scarcity by the combined water quantity and quality solutions. [ABSTRACT FROM AUTHOR]

Due to the limited resources of the water and the excessive growth of the population, the use of sewage in agriculture and green space irrigation is inevitable. In this regard, a research was carried out in city of Yazd to investigate the effect of irrigation with refined and untreated sewage on Rosmarinus officinalis, a species in the urban green space. This study was carried out in a randomized complete block design with five treatments (drinking water, refined wastewater, non-refined wastewater, refined wastewater + drinking water with a ratio of 1:1 and non-refined wastewater + drinking water with a ratio of 1:1) and 5 replicates. The results of chemical characterization of irrigation treatments showed that pH (7.2) and EC (1.27 ds/m) and the concentration of heavy metals, Pb and Zn in the effluent were in accordance with the FAO standard (0.5 and 0.24 mg/l, respectively) but cadmium concentration in both treatments was higher than the FAO standard level (0.02 and 0.04 mg/l). The results of morphological traits of Rosmarinus officinalis showed that there was no significant difference between different concentrations of sewage in terms of plant growth and root dry weight (p >0.05). The effect of irrigation with wastewater on dry weight of shoot and plant diameter was statistically significant (p

Today, one of the biggest challenges facing the world is the lack of water, especially in the agricultural sector. In this research, we investigated the effects of irrigation method and deficit irrigation with the urban refined effluent on biomass, grain yield, yield components and water use efficiency in single grain crosses 704 maize. This research was carried out in a randomized complete block design with two irrigation systems (furrow irrigation (F) and drip irrigation (T)) and three levels of deficit irrigation treatments of 100 (D1), 75 (D2) and 55 (D3) percent of water requirements in three replications, in 2017, at the collage of Abourihan Research field, University of Tehran, in Pakdasht County. The results showed that the highest yield of biomass was 2.426 Kg m-2 for full drip irrigation treatments; also, there was no significant difference between D1 and D2 treatments. The highest grain yield was 1.240 kg m-2 for the complete drip irrigation treatment. The highest biomass water use efficiency was obtained for the treatment of 75% drip irrigation, which was equal to 5.3 kg per cubic meter of water. Therefore, a drip irrigation system with 75% water requirement is optimal and could be recommended. [ABSTRACT FROM AUTHOR]

Phytoremediation method, in combination with porous concrete and some additives, has been examined in order to reduce the contamination of unconventional water resources. This treatment system is economically cost-effective and easy to apply, compared to other treatment methods. The current study was focused on evaluating the effects of arrangement of vetiver grass and porous concrete specimens (four types of grass-specimens arrangements), vetiver grass layout on polystyrene sheets (5 × 5 and 10 × 10 cm spacing), porous concrete mixture (basic design as control, basic design + 5% zeolite, basic design + 10% zeolite, basic design + 5% pumice), temperature of the test room (10 ± 2, 20 ± 2 and 30 ± 2 °C), type of the unconventional water (domestic wastewater effluent and urban runoff) and Portland cement type (2 and 5) on the reduction of biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and fecal coliforms. Taguchi method (robust design) and Qualitek-4 software were used to optimize the combination of aforementioned factors. Results indicated that temperature was the most effective parameter on reducing the BOD, COD, and fecal coliforms. The vetiver grass layout on the polystyrene sheets and porous concrete mixture design were more effective than vetiver grass-porous concrete arrangement. Effect of vetiver grass roots was significant in reducing the TSS content. The cement type had minimum impact on reducing the qualitative parameters of the wastewater samples. Based on the results, combination of 10 × 10 cm spacing of vetiver grass on polystyrene sheets, third type of vetiver grass-porous concrete arrangement, porous concrete mixture with 10% zeolite, Portland cement Type 2, and room temperature of 30 ± 2 °C was the best for improving the quality of wastewater effluent as compared to urban runoff. The treated effluents can be used with caution for urban green spaces or irrigation purposes, and the difficulties of the proposed combined system should be taken into consideration. [ABSTRACT FROM AUTHOR]

Global water scarcity and air pollution by greenhouse gases have amplified the need to use unconventional water and environmental friendly materials in the concrete industry. Accordingly, the present study was conducted to investigating interaction of three levels of water quality (tap water, greywater and a mixture of their equal ratio), four levels of substitution of cement by zeolite in the concrete mix design (0%, 10%, 20% and 30%), two levels of cement content (250 and 350 kg m−3) and seven curing ages (3, 7, 28, 56, 90, 180 and 365 days) on compressive strength of concrete. For this reason, 504 concrete specimens based on 168 treatments with three replications were constructed. Regarding the numerous treatments in the current study as well as the lack of statistical analysis in previous studies, the compressive strength data were analyzed based on a completely randomized design with factorial experiment using analysis of variance (ANOVA) and means comparison (least significant difference: LSD) tests. The results showed that the simultaneous use of unconventional water and zeolite up to 20% in the concrete mix design not only did not significantly reduce the compressive strength of concrete but also significantly increased this property in the cement content 350 kg m−3 while the efficiency of these materials in the cement content 250 kg m−3 was not remarkable. However, considering the interaction of these three factors, which means different effects of water quality and application percentage of zeolite on different contents of cement, choosing the best combination of zeolite percentage and water type according to the cement content should be based on the in- situ mix design test. [ABSTRACT FROM AUTHOR]

Shortage of water resources and renewable per capita in last 30 years is put Iran on crisis threshold. Wastewater reuse is one of the battle solutions for water shortage and prevents wastewater depletion and environmental pollution. Thus, a pilot scale experiment was carried out to evaluate an integrated anaerobic/aerobic treatment for removal of BOD5 and COD, also to reduction of hydraulic retention time by considering optimum removal efficiency. The pilot was an anaerobic/aerobic bioreactor type under continuous-feeding regime based on a central composite design. The pilot was studied in different retention time and aeration was carried out between 5-15 hours. According to different retention times for COD removal efficiency, 24 hours was selected as optimum hydraulic retention time, that it is comparable to those obtained for 48 hours and over in plant roughly and could remove COD and BOD in acceptable ranges, results showed that average removal efficiency for BOD5 were 63.86 and 83.99 percent in aerobic and anaerobic phases, respectively. The average removal efficiency for COD was 76.5 and 74.35 percent for anaerobic and aerobic sections, respectively. The average removal efficiency for BOD5 and COD in this integrated aerobic-anaerobic pilot 95.24 and 94.8 percent, respectively. [ABSTRACT FROM AUTHOR]

Condensation Irrigation (CI) is a combination of simultaneous desalination and irrigation/drinking water production. As saline water evaporates in a solar distiller and the hot and humid air is transferred into an underground pipeline, fresh water will condense on the inner pipe surface due to cooling of air by the ground. The water thus condensed infiltrates into the soil through pores in the perforated drainage pipes laid in the ground to transfer the humidified air. In this study, the CI system was developed using common buried pipes to determine the amount of water produced. In this setup, condensed water is collected at the end of the pipe to be used for drinking. Observations and calculations indicated a mean water production capacity of 4 liters every 8 hours along a pipe 25m long. Less water was produced on the first day because some of the water was lost to the wetting of the internal pipe walls. Finally, examination of temperature effects revealed that water production along the pipe reduces as we move farther away from the inlet part of the pipe.

The limitation of fresh water resources in the most parts of the country has necessitated the use of unconventional water resources. Wastewater is one of these unconventional sources, however the environmental impacts of wastewater reuse should be carfully considered. The present study aimed to examine the effect of the rubber powder to absorb the heavy metals of lead, zinc and manganese in laboratory scale. The batch tests to evaluate the absorption equilibrium time were conducted in constant pH of 5.5 and the soluble metal concentration equal to 100 mg per liter. The adsorption kinetic results showed, the removal efficiency of lead, zinc and manganese were 67.2, 74.3 and 39.9 percent, respectively. Time to reach equilibrium for zinc and manganese were 180 and 120 minutes, respectively. But lead does not reach equilibrium during the 180 minutes of testing time. Also, the adsorption isotherms tests were performed for these metals and the data were fitted with the linear, Langmuir and Freundlich models. The results showed that the Freundlich adsorption model with regression coefficient equal to 99 percent was the best compliance with the laboratory results.

In this research, a pilot phytoremediation experiment was conducted to evaluate the effectiveness of vetiver grass (Vetiveria zizanioidesL. Nash) in the uptake of contaminants from two unconventional water samples. The vetiver was hydroponically planted in two unconventional water samples taken from a mine (W1) and saline groundwater taken from wells located around the mine area (W2). Although waters from the Golgohar mining site are not permitted to escape into public waters and the aim of the current research was to examine the efficiency of the vetiver system in the reusage of water for ore processing plant, this study just focused on salinity and thus the total dissolved solids (TDS), electrical conductivity (EC), total hardness (TH), anions (SO4, Cl) and cations (Na, K, Mg, Ca) were considered and analysed. The results indicated that all five elements were distributed more in the shoots than in the roots of the vetiver, particularly Na, K and Ca, as seen from the average concentration ratios of 74.7, 42, 55.9 43 and 60.2% for Na, Cl, Ca, Mg and K, respectively. The weed grown in W2with the upper plant growth had the highest SO4, Na, K, Ca, Cl and Mg removal efficiencies of 70.9, 59.1, 58.4, 51.5, 48.7 and 23.8%, respectively, whereas the weed grown in W1showed efficiency of up to 43.6% Mg removal from the water samples. The results showed that treatment efficiencies of total hardness, TDS and EC of water samples were equal to 46, 31.5 and 28.3% for mine wastewater and 45.1, 33 and 28% for groundwater in the fourth week, respectively. [ABSTRACT FROM AUTHOR]

• Presented novel water footprint assessment method for China's oil and gas production. • Proposed unconventional water use factor to measure nontraditional water use. • Blue water decreased and unconventional water increased in oil and gas production. • Natural (esp. unconventional) gas exploitation may challenge China's water protection. • Total blue water footprint of oil and gas production in China may rise by 43% by 2030. Oil and gas production necessitates substantial use of water. Inspired by the water footprint theory, in this study, we proposed a novel factor to measure unconventional water use in various processing and production activities. The proposed factor was used to establish a method for evaluating the water footprint in oil and gas production. Through analyzing water use characteristics in oil and gas exploration, construction, production, and operation in China, it was found that the direct blue and grey water footprints of oil and gas production in 2018 were 3.08 and 6.64 m3/toe, respectively. Technological innovation and increased use of unconventional water reduced the blue water footprint. The unconventional water use factor was 4.61 m3/toe in 2018. Because of the growth of natural gas, especially unconventional production, China is predicted to require 1.42 billion m3 of water for oil and gas production in 2030, marking a 43% increase. [ABSTRACT FROM AUTHOR]

• Domestic wastewater and rainwater are effective nontraditional water resource in green building residential community. • A2O-MBR-based system can be efficient treat wastewater for reusing and recycling. • Membrane fouling rate is accelerated at low temperatures in winter. • Cost-benefit analysis based on total life cycle showed A2O-MBR is profitable in green building residential community. Unconventional water reclamation, recycling, and reuse have been identified as the major approaches for addressing water scarcity in China. The aim of this study was to evaluate the technical and economic feasibility of water reclamation plants (WRP) based on an anaerobic-anoxic-oxic membrane bioreactor (A2O-MBR) system for unconventional water resource (domestic wastewater and rainwater) treatment and reuse in green building residential community. During a year operation and evaluation process, average chemical oxygen demand (COD), biochemical oxygen demand (BOD 5), total nitrogen (TN) and total phosphorus (TP) removal efficiencies averaged 83.7 ± 3.2%, 91.6 ± 2.6%, 69.0 ± 6.5% and 74.5 ± 5.5%, respectively. The effluent quality of wastewater treated by the A2O-MBR system complied with the water quality standards for reuse for green building residential community or for direct discharge. Typical seasonal fluctuations of temperature, COD loading rate, BOD 5 /COD and COD/TN were the key factors affecting pollutants removal efficiencies, and the membrane fouling rate was accelerated at low temperatures. The total cost of capital and operation was 0.406 $/m3, a cost-benefit analysis incorporating both capital and operating expenditures showed that more than 60% of the reclaimed water is reused in the green building, and the full-scale WRP exhibits a positive net present value. These results demonstrated that A2O-MBR is an efficient and profitable technology for nontraditional water resource recycling in green building residential communities in terms of technical and economic feasibility. [ABSTRACT FROM AUTHOR]