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•Nature-based solutions (NBS) are a viable option for greywater (GW) treatment.•Review of case studies provided numerical thresholds for hydraulic design of NBS.•Life cycle assessment ...studies demonstrated the benefits of NBS for GW treatment.
Recognizing greywater as a relevant secondary source of water and nutrients represents an important chance for the sustainable management of water resource. In the last two decades, many studies analysed the environmental, economic, and energetic benefits of the reuse of greywater treated by nature-based solutions (NBS). This work reviews existing case studies of traditional constructed wetlands and new integrated technologies (e.g., green roofs and green walls) for greywater treatment and reuse, with a specific focus on their treatment performance as a function of hydraulic operating parameters. The aim of this work is to understand if the application of NBS can represent a valid alternative to conventional treatment technologies, providing quantitative indications for their design. Specifically, indications concerning threshold values of hydraulic design parameters to guarantee high removal performance are suggested. Finally, the existing literature on life cycle analysis of NBS for greywater treatment has been examined, confirming the provided environmental benefits.
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•With climate change, maintenance of crop productivity is a challenge.•Drought is a major consequence of climate change.•Drought affects physiological, biochemical and genetic ...processes of the plant.•Drought can be managed with combination of agronomic, breeding and biotechnological approaches.
Drought is the most important crop production limiting factor in the changing climate scenario and its intensity is predicted to increase in future. Sunflower is an important oilseed crop having 8% share in the world oilseed production. Although, it is a moderately drought tolerant crop, severe drought causes reduction in the seed and oil production. Therefore, to ensure sustainable sunflower achene and oil production, it is very important to understand the relationship among the physiological, biochemical, genetic and agronomic basis of drought for its sustainable management. Impact of drought stress on various aspects of sunflower has been reported earlier but there is not a single study describing the physiological, biochemical and genetic basis of drought in sunflower at molecular and crop level. In this review manuscript, influence of drought on sunflower achene yield and oil quality has been analyzed critically at both cell, plant and crop level, and the possible management options to mitigate the severity of the drought stress are proposed. Available literature describing the impact of drought stress on physiological and biochemical aspects (like, photosynthesis, water relations, nutrient uptake and oxidative damage), morphological and growth parameters and achene yield and oil quality has been discussed critically. Based on the discussion on the impact of drought stress, various management strategies, such as breeding for drought tolerance (conventional or biotechnological), exogenous application of hormones and osmoprotectants, seed treatment and soil nutrient management has been reviewed and discussed. It is concluded from discussion that sunflower responds to water stress by osmotic adjustments, turgor maintenance, carbon assimilation maintenance and hormonal regulations. A comprehensive research on integration of different management options, including agronomic management, conventional breeding and modern biotechnological advances, is needed for the sustainable improvement of sunflower achene yield and oil quality under drought stress. This may also contribute significantly under a climate change scenario.
The world is facing water crises because freshwater scarcity has become a global issue due to rapid population growth, resulting in the need for more industries, agriculture, and domestic sectors. ...Therefore, it is challenging for scientists and environmental engineers to treat wastewater with cost-effective treatment techniques. As compared to conventional processes (physical, chemical, and biological), advanced oxidation processes (AOP) play an essential role in the removal of wastewater contaminants, with the help of a powerful hydroxyl (OH•) through oxidation reactions. This review study investigates the critical role of O3-based Advanced Oxidation Processes (AOPs) in tackling the complex difficulties of wastewater treatment. Effective treatment methods are critical, with wastewater originating from various sources, including industrial activity, pharmaceutical manufacturing, agriculture, and a wide range of toxins. O3-based AOPs appear to be powerful therapies capable of degrading a wide range of pollutants, including stubborn organics, medicines, and pesticides, reducing environmental and human health risks. This review sheds light on their efficacy in wastewater treatment by explaining the underlying reaction mechanisms and applications of several O3-based AOP processes, such as O3, O3/UV, and O3/H2O2. Ozone, a powerful oxidizing agent, stimulates the breakdown of complex chemical molecules by oxidation processes, which are aided further by synergistic combinations with ultraviolet (UV) radiation or hydrogen peroxide (H2O2). Notably, while ozonation alone may not always produce the best outcomes, it acts as an essential pretreatment step prior to traditional treatments, increasing total treatment efficiency. Furthermore, O3-based AOPs' transformational capacity to convert organic chemicals into simpler, more stable inorganic forms with little sludge creation emphasizes its sustainability and environmental benefits. This study sheds light on the processes, uses, and benefits of O3-based AOPs, presenting practical solutions for sustainable water management and environmental protection. It is a valuable resource for academics, engineers, and politicians looking for new ways to combat wastewater contamination and protect water resources.
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•The treatment efficiency is higher for ozone-based AOP methods illustrated.•The numerous ozone-based reaction mechanisms and applications of AOP are discussed.•The merged techniques are economically advantageous to various methods narrated.
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•Interactions of the food-energy-water nexus are quantified in Phoenix Metro.•Preserving food production and megadrought will compromise groundwater safe-yield.•Preserving food ...production and megadrought will increase energy needs for water.•Solar photovoltaic technologies will support groundwater sustainability.
Quantifying the interactions of the food-energy-water (FEW) nexus is crucial to support new policies for the conjunctive management of the three resources. Currently, our understanding of FEW systems in metropolitan regions is limited. Here, we quantify and model FEW interactions in the metropolitan area of Phoenix, Arizona, using the Water Evaluation and Planning (WEAP) platform. In this region, the FEW nexus has changed over the last thirty years due to a dramatic population growth and a sharp decline of cultivated land. We first thoroughly test the ability of WEAP to simulate water allocation to the municipal, agricultural, industrial, power plant, and Indian sectors against historical (1985–2009) data. We then apply WEAP under possible future (2010–2069) scenarios of water and energy demand and supply, as well as food production. We find that, if the current decreasing trend of agricultural water demand continues in the future, groundwater use will diminish by ~23% and this would likely result in aquifer safe-yield and reduce the energy demand for water. If agricultural activities decrease at a lower rate or a multidecadal drought occurs, additional (from 7% to 33%) water from energy-intensive sources will be needed. This will compromise the ability to reach safe-yield and increase energy demand for water up to 15%. In contrast, increasing the fraction of energy produced by solar power plants will likely guarantee safe-yield and reduce energy demand of 2%. This last solution, based on an expanded renewable portfolio and current trends of municipal and agricultural water demand, is also projected to have the most sustainable impacts on the three resources. Our analytical approach to model FEW interconnectivities quantitatively supports stakeholder engagement and could be transferable to other metropolitan regions.
Limited precipitation restricts crop yield in the North China Plain, where high level of production depends largely on irrigation. Establishing the optimal irrigation scheduling according to the crop ...water requirement (CWR) and precipitation is the key factor to achieve rational water use. Precipitation data collected for about 40 years were employed to analyze the long-term trend, and weather data from 1984 to 2005 were used to estimate the CWR and irrigation water requirements (IWR). Field experiments were performed at the Luancheng Station from 1997 to 2005 to calculate the soil water consumption and water use efficiency (WUE). The results showed the CWR for winter wheat and summer maize were similar and about 430
mm, while the IWR ranged from 247 to 370
mm and 0 to 336
mm at the 25% and 75% precipitation exceedance probabilities for winter wheat and summer maize, respectively. The irrigation applied varied in the different rainfall years and the optimal irrigation amount was about 186, 161 and 99
mm for winter wheat and 134, 88 and 0
mm for summer maize in the dry, normal and wet seasons, respectively. However, as precipitation reduces over time especially during the maize growing periods, development of water-saving management practices for sustainable agriculture into the future is imperative.
The sustainable use of groundwater resources is highly important for regional groundwater system safety and food security, especially in large-scale agricultural planting areas. In the Sanjiang Plain ...(SJP) in Northeast China, irrigation water consumption has increased sharply due to the large-area "conversion of dry land (mainly maize and soybean fields) into rice fields", threatening the regional groundwater system security. However, little is known about the impact of large-scale agricultural planting structure adjustment (i.e., changes in cropping systems) on regional groundwater sustainability. This study estimated the groundwater storage anomaly (ΔGWS) using the Gravity Recovery and Climate Experiment (GRACE) satellite data and the Global Land Data Assimilation System data. Additionally, the groundwater sustainability index (SI) of this region was evaluated based on GRACE Groundwater Drought Index (GGDI). Collectively, the influence of agricultural planting restructuring on the SJP groundwater sustainability was analyzed. The findings were: (1) The groundwater reserves in SJP and Xingkai Lake Plain decreased with maximum declines of 6.79 and 10.37 cm/year, respectively. (2) The groundwater sustainability deteriorated rapidly after 2009, from extremely high to extremely low levels. The lowest sustainability was observed in the Jiansanjiang area, which underwent the most drastic adjustment of agricultural planting structure. (3) Although precipitation increase can alleviate groundwater overexploitation, the groundwater sustainability continued to deteriorate due to the sharp increase in irrigation water consumption arising from the large-scale land conversion. Curbing the expansion of paddy rice fields or reducing their planting areas can restrain the demand for irrigation water. Moreover, proactively designing diversion projects to increase available surface water supply can also effectively achieve sustainable agricultural development in this region.
•Evolution and driving factors for regional groundwater sustainability (SI) were evaluated.•Groundwater declined from extremely high to very low sustainability.•SI continuously deteriorated due to the sharp increase in irrigation water consumption.•Curbing rapid expansion of paddy fields and designing water diversion projects to improve agricultural SI.
•PRD was found to be a valuable and sustainable production strategy.•PRD induced physiological mechanisms responses enabling trees to tolerate the imposed water stress.•Monitoring transpiration by ...heat pulse sap flow measurements is an effective tool for detection of drought stress.•ERT monitoring allows to identify the root water uptake processes at fine spatial scale.
We have studied the effects of partial root-zone drying (PRD) on plant physiological response, plant-soil water dynamics, yield and fruit quality of young orange trees during the irrigation seasons 2013 and 2014 in an orchard located in Eastern Sicily (Southern Italy). The irrigation treatments included: (i) full irrigation (T1), with trees irrigated by supplying 100% of crop water demand using micro-irrigation systems; and (ii) alternate partial root-zone drying (T4), with trees irrigated at 50% of crop water demand. Minimally invasive electrical resistivity tomography (ERT) was adopted to help quantify root-water-uptake (RWU) processes at the finer (decimetric) spatial scale. Results show that, compared with the full irrigation treatment, PRD at 50% of crop water demand (ETc) increased the fruit yield by 20% in 2013 and 10% in 2014. The PRD irrigation treatment, which induces a reduction of the wetted soil volumes, had also obvious positive effects on water use efficiency (WUE), compared to full irrigation. From the results of this study, we concluded that when water resources are limited, PRD at 50% level of ETc is an efficient water saving strategy to increase WUE, while other physiological and growth parameters are practically unaffected.
•Systematic analysis of a megacity water management model and economic benefit-costs.•Flood mitigation solutions by optimal combination of multiple LID devices.•Upstream and highland areas are ...suitable for buffer and retaining LIDs, respectively.•Green roof and bioretention cell show best B/C values for all rainfall RPs in Taipei.•LID combinations are effective in reducing peak flow and delaying peak time.
This study establishes an innovative systematic optimization model for megacity flood mitigation by combining multiple Low Impact Development (LID) devices, taking into consideration a Benefit-Cost (B/C) Analysis. The contributions provided by this study include: (1) analysis of flooding consequences on a developing megacity; (2) development of a technical approach enabling an automatic and effective optimization process, linking with an embedded Storm Water Management Model (SWMM); and (3) proposal of adaptive solutions using a combined layout design scheme. Our investigation sets the Benefit/Cost ratio as the objective function to deal with flooding in all return periods (RPs). The decision variables correspond to the allocated areas and quantity of LID devices, including porous pavements, bioretention cells, infiltration trenches, rain barrels, vegetable swales, green roofs, and tree boxes. Under such layout, the flooding loss was simulated with SWMM, and the optimal solution was solved by employing a Simulated Annealing (SA) algorithm. Min-Sheng Community in Taipei is chosen as a study area for demonstrating the applicability of the developed model. Results show that the B/C ratio of identified optimal design can reach 1.448, with green roofs and bioretention cells as main devices, and rain barrels and porous pavements as secondary supplies. Regarding rainfalls in all RPs, the peak flows and delay of peak times at Fu-Yuan Pumping Station can decrease significantly in the range of 5.75–29.80% and 12.50–20%, respectively; and 9.52%–23.49% and 12.50%–37.5% at the subcatchments. The efficiency of flood detention is higher for low RPs than high RPs, while the time-delay ability is smaller.
Treated wastewater reuse is increasingly important for sustainable water resource management, especially in water-stressed countries located in the world's arid regions that rely on groundwater and ...desalination process for meeting their water demands. This study investigates the socio-demographic variables influencing public perceptions of reusing grey and mixed wastewater for non-domestic uses: firefighting, swimming pools, and car washing. Data were collected from 624 households in the Dammam Metropolitan Area, Saudi Arabia using a structured questionnaire and analyzed using descriptive and inferential statistics. The results from logistic regression indicates that the likelihood of a household to accept reusing treated mixed wastewater is influenced by gender with odds ratio (OR) of 2.71–2.18, residential location (OR = 1.32–1.03), age (OR = 1.22–0.18) and educational level (OR = 1.33–0.98), with a tendency for more acceptance of treated grey wastewater than mixed wastewater. These findings showcase the difficulty that the country could face concerning the public acceptance of treated wastewater for non-domestic uses to augment current freshwater sources even among the educated class. This study is significant because sustainably meeting the country's rising water demands requires the stringent implementation of strategic wastewater reuse policy, including bold steps towards wastewater streams segregation, and intensive public awareness campaigns to change negative perceptions on treated sewage effluent. This study concludes that a substantial reduction in the country's reliance on costly desalinated water and fast depleting non-renewable groundwater requires complete reuse and recycling of treated wastewater for wider non-conventional purposes.
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•Treated wastewater is a viable water resource and a necessity for arid countries.•This study explores public acceptability of reusing treated wastewater in Saudi Arabia.•Public acceptability of reusing treated wastewater was low even among educated people.•Wastewater streams segregation and changing people's negative perceptions are needed.•Stategic management requires treated wastewater reuse in wide unconventional domains.
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