查看更多>>摘要：This study examines the intricate relationship between Delhi's urban water system and environmental factors, with a specific emphasis on the challenges posed by urbanization. It investigates the present conditions of the water resources, infrastructure, and governance in the National Capital Territory (NCT) of Delhi and identifies significant difficulties, such as depletion of groundwater and inadequate access to water. Additionally, it explores innovative approaches to strengthen supply internalization, such as rainfall harvesting, wastewater recycling, and demand management strategies. Therefore, this document establishes a path for future research endeavors and policy suggestions that aim to promote a fair, effective, and environmentally sustainable future for water in Delhi.
查看更多>>摘要：Anti-filtration recharge wells are a class of recharge facilities in groundwater reservoirs with their own anti-filtration function, and aquifer clogging is a key issue in recharge, in this paper, the process of recharging groundwater by rainfall flood water recharge from an anti-filtration recharge well was simulated by indoor sand column test, and the change of permeability coefficient, turbidity at the outlet, and the distribution of suspended particulate matter at the end of the experiment were measured and computed, so as to analyze and study the effect of filtration in anti-filtration recharge wells and carry out the contrast test with ordinary recharge wells without a recharge pool. Compared with ordinary recharge wells, the anti-filter layer in the recharge pool of anti-filtration recharge wells can largely remove suspended matter in recharge water and intercept suspended matter at the surface, thus preventing aquifer clogging, and it is recommended that the anti-filter layer should be cleaned up and replaced regularly according to the experimental results, and this study provides a reference for the practical application of anti-filtration recharge wells.
Ahmad AlomariFernando P. CarvalhoMuneer Aziz SalehEman Bilbeisi...
3666-3679页
查看更多>>摘要：The study aimed to evaluate the radiation doses received by workers at a pilot water treatment plant (WTP) in Jordan, It also examined the concentrations of gross alpha, gross beta, and radium activities in both groundwater and treated water, along with a radiological risk assessment for the waste generated by the treatment process. The radioactivity levels of gross alpha and gross beta in the groundwater were found to exceed the established drinking water limits, In the pilot WTP, two methods were applied for water treatment, namely, ceramic ultra-filtration (CUF) and reverse osmosis (RO), both of which produced treated water that met drinking water quality standards. The annual effective dose from external radiation exposure to the WTP workers was found to be less than 0.007 msv y~(-1) (during the filters backwash operation). However, the average annual dose from internal radiation due to inhalation of radon released from groundwater reached 3.2 mSv y~(-1), exceeding the 1 mSv y~(-1) limit. Therefore, monitoring radon levels in workplaces is recommended. Radioisotope concentrations in the waste (sludge) stockpiles exceeded clearance levels, requiring them to be treated as radioactive waste. Overall, the WTP successfully produced drinking water that met quality standards, and the methods used could be replicated in other locations.
查看更多>>摘要：Watershed forests offer crucial ecosystem services for hydrological systems. This study provides comprehensive insights into sediment retention within the Mangla watershed. We analyzed spatial layers from Sentinel-2 imagery, land use data, weather, soil properties, and terrain characteristics to identify soil erosion and sediment delivery hotspots. Using the Integrated valuation of Environmental Services and Tradeoffs-sediment delivery ratio (InVEST-SDR) model, we quantified sediment exported to the downstream Mangla Dam. The InVEST-sedi-ment retention (lnVEST-SR) model estimated the sediment retention capacity of various land cover types. Our findings show that forests retained 20,300.70 tons of sediment in 2017 and 29,887.60 tons in 2021, making them the primary source of sediment retention. The economic value of this ecosystem service was approximately USD 2.59 trillion for 973,168.51 ha of forest in 2017 and USD 4.02 trillion for 1,023,927 ha in 2021. Understanding the dynamics and economic value of this forest ecosystem service at a large watershed scale provides essential insights for decision-making and conservation efforts aimed at protecting water resources and ecological integrity.
查看更多>>摘要：To investigate the response of wheat to drought stress under different plantation systems, two field experiments were carried out in 2021/22 and 2022/23 in Arsanjan, Iran. The main plot was three different plantation systems (flat planting, 60, and 120 cm raised beds) and the sub plots were irrigation levels at 100% (control), 80% (medium stress), and 60% (severe stress) of crop evapotranspiration. Raised bed planting increased grain yield by 24% compared to flat cultivation. This increase for biological yield was about 17%, the number of ears was 7%, and the number of seeds per ear was 21%. Drought stress caused a significant decrease in grain yield (46.4%), number of ears (20.5%), seed number (30.3%), biological yield (45.9%), chlorophyll a (31.8%), chlorophyll b (28.1%) and relative water content (5.3%) and increased, proline content (24.3%) and ion leakage (147.3%). Water use efficiency was increased in raised bed planting and deficit irrigation treatments. The decrease in yield due to drought stress was moderated to some extent in the raised bed system and therefore cultivation on raised beds is suggested as a suitable planting pattern to improve yield and WUE in wheat under conditions similar to the experimental area, especially under water shortage conditions.
查看更多>>摘要：Understanding hydraulic conductivity is essential in porous media as it dictates the capacity of fluids to permeate through these substances. This research investigated the impact of chemical modification using fly ash on hydraulic conductivity. The coefficient of hydraulic conductivity along the bedding plane at different angles of orientations was predicted by employing machine learning techniques such as gene expression programming (GEP), artificial neural networks (ANNs), and regression tree (RT), considering various influencing parameters, as the amount of fly ash in the porous medium rises, the hydraulic conductivity decreases. The statistical results demonstrate that the proposed ANN model effectively forecasted the horizontal hydraulic conductivity, It achieved the highest R~2 value (0.989), the lowest mean absolute percentage error value (5.772), the lowest scatter index value (0.040), and the lowest Akaike Information Criterion value (-2,359.914) compared to the GEP, RT, and previously established approaches. Moreover, a novel equation has been proposed for determining horizontal hydraulic conductivity, which can be used for any stratified medium, distinguishing this work from previous ones. These findings can inform global practices in mitigating groundwater contamination, enhancing irrigation efficiency, and improving the design of subsurface fluid flow systems, making it a valuable contribution to both academic and practical applications worldwide.
查看更多>>摘要：The main objective of the present study is to evaluate groundwater quality for irrigation purposes in the central-western part of Haryana state (India). For this, 272 groundwater samples were collected during the pre- and post-monsoon periods in 2022. Several indices, including SAR, PI, Na%, KR, magnesium adsorption ratio (MAR), and IWQI were derived. The results of SAR, Na%, and KR values indicate that the groundwater is generally suitable for irrigation. On the other hand, PI and MAR exceeded the established limits, primarily showing issues related to salinity and magnesium content in the groundwater. Furthermore, according to the IWQI classification, 47.06 and 25% of the total collected samples fell under the 'severe restriction for irrigation' category during the pre-monsoon and post-monsoon periods, respectively. Spatial variation maps indicate that water quality in the western portion of the study area is unsuitable for irrigation during both periods. Three ML algorithms, namely RF, SVM, and XGBoost were integrated and validated to predict the IWQI. The results revealed that the XGBoost with random search achieves the best prediction performances. The approaches established in this study have been confirmed to be cost-effective and feasible for groundwater quality, using hydrochemical parameters as input variables, and highly beneficial for water resource planning and management.
Alma L. Aguilar-SantosChristina SiebeRuth Fuentes-GarciaBlanca Prado-Pano...
3744-3758页
查看更多>>摘要：This study examines the formation of trihalomethanes (THMs) in wastewater intended for crop irrigation and its relationship with dissolved organic carbon (DOC), aromaticity, and residual chlorine. The research takes a dual approach: assessing spatial distribution through field samples from canals now distributing treated, chlorinated wastewater and analysing vertical percolation of wastewater through soil previously irrigated with untreated, non-chlorinated wastewater for over 100 years. Spatial analysis reveals that THMs are present in wastewater before treatment, with concentrations increasing post-treatment. Although DOC levels decrease after treatment, their aromaticity remains unchanged, suggesting the persistence of labile DOC. The presence of THMs in treated wastewater from irrigation canals may result from shorter travel distances or increased chlorine use during the COVID-19 pandemic. Vertical soil column experiments indicate a correlation between THM generation, water source, and soil type. Results show that THMs are retained in the soil, where labile DOC is trapped, reducing its concentration while potentially releasing DOC from humic substances. Despite this, THM concentrations do not pose a risk to aquifers, though ongoing monitoring is important should soil and/or treatment methods be altered.
查看更多>>摘要：Water distribution networks (WDNs) are an essential urban infrastructure, with their performance directly influencing societal well-being. Our study applied to a real network model that employs a 24-h simulation with 1-h time steps and evaluates the impact of leaks and loss in the pipe cross-sectional area on WDN hydraulic performance as experienced by end users. Adhering to a UK utility's 20-m head pressure requirement as the water main benchmark, we present two new customer-oriented performance indices (CPls) centred on network reliability and pressure deficit severity. The new CPls adeptly quantify network performance degradation due to pipe deterioration. This degradation translates directly to a poor customer experience, highlighting the potential for these CPls to pinpoint areas of the network where performance levels are compromised. Furthermore, the CPls identify individual pipes within the network where defects would severely impact network performance and the sets of pipes which, when simultaneously experiencing defects, would lead to a more severe loss in network performance. Results show that the CPls capture relatively small performance declines and identify sensitive pipes impacting network performance, providing insights for optimised inspection and maintenance intervention to provide better customer service.
Renske HoondertMilou M. L DingemansTineke SlootwegCheryl Bertelkamp...
3776-3795页
查看更多>>摘要：Chemical water quality monitoring is increasingly complemented with bioassays. The performance of drinking water treatment technologies was evaluated with bioassays. CALUX bioassays and the Ames fluctuation bioassay for mutagenicity were used to analyze the responses of raw feed water with and without a spiking mixture of organic contaminants in different pilot-scale water treatment trains applying advanced oxidation processes, reverse osmosis and filtration with activated carbon for the preparation of drinking water. In general, CALUX responses in the spiked feed water were in the same range as in the unspiked feed water, indicating that spiking did not significantly elevate the activity measured in the feed water. This observation was in line with a calculation of the combined additive behavior of the spiking mixture using bioactivities of the spiked chemicals in analog bioassays from ToxCast. This calculation gave no indication of a measurable response in the bioassays to be expected by the spiking, except for oxidative stress. Responses in the Ames fluctuation assay in most feed water were in some cases increased by advanced oxidation processes (AOPs) and mostly removed by active concentrations. The bioassay responses demonstrate the removal of emerging chemicals with different mechanisms of action by different water treatment technologies.
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