Drainage Water Research Articles

Earthworms and plants can decrease soil greenhouse gas emissions by modulating soil moisture fluctuations and soil macroporosity in a mesocosm experiment.

Earthworms can stimulate microbial activity and hence greenhouse gas (GHG) emissions from soils. However, the extent of this effect in the presence of plants and soil moisture fluctuations, which are influenced by earthworm burrowing activity, remains uncertain. Here, we report the effects of earthworms (without, anecic, endogeic, both) and plants (with, without) on GHG (CO2, N2O) emissions in a 3-month greenhouse mesocosm experiment simulating a simplified agricultural context. The mesocosms allowed for water drainage at the bottom to account for the earthworm engineering effect on water flow during two drying-wetting cycles. N2O cumulative emissions were 34.6% and 44.8% lower when both earthworm species and only endogeic species were present, respectively, and 19.8% lower in the presence of plants. The presence of the endogeic species alone or in combination with the anecic species slightly reduced CO2 emissions by 5.9% and 11.4%, respectively, and the presence of plants increased emissions by 6%. Earthworms, plants and soil water content interactively affected weekly N2O emissions, an effect controlled by increased soil dryness due to drainage via earthworm burrows and mesocosm evapotranspiration. Soil macroporosity (measured by X-ray tomography) was affected by earthworm species-specific burrowing activity. Both GHG emissions decreased with topsoil macropore volume, presumably due to reduced moisture and microbial activity. N2O emissions decreased with macropore volume in the deepest layer, likely due to the presence of fewer anaerobic microsites. Our results indicate that, under experimental conditions allowing for plant and earthworm engineering effects on soil moisture, earthworms do not increase GHG emissions, and endogeic earthworms may even reduce N2O emissions.

Aquifers Recharge Potentiality Evaluation using Bivariate and Multivariate Statistical Analysis: A Case Study in Malwathu Oya River Basin

An aquifer is a body of porous rock or sediment saturated with groundwater that plays a vital role in the hydrological cycle. Due to rapid population growth and urbanization, these valuable resources face threats like climate changes, pollution, and over-exploitation. Overdraft, where extraction exceeds recharge, can lead to groundwater depletion. Although Sri Lanka is not considered a water- scarce country, it faces rising water demands due to rapid population growth. Especially in dry zones, groundwater is crucial for drinking and agriculture; unauthorized agro-wells exacerbate groundwater issues. Therefore, this research aims to assess groundwater recharge potential zones in Malwathu Oya river basin using Bivariate and Multivariate statistical analysis. Comparing these techniques will lead to the precise identification of potential recharge areas. And this study primarily focuses on the implementation of GIS to find solutions for this kind of challenge without performing field investigations. Therefore, eight conditioning factors; water level, electrical conductivity, lithology, soil, slope, lineament density, drainage density and land use were selected as groundwater recharge influencing factors. The well inventory database consisted of 380 well locations and, out of these, 70% was considered as the training dataset, and the remaining 30% was taken as the testing data set. Groundwater recharge potential maps (GRP) were developed in ArcGIS 10.8, based on the results obtained from Frequency Ratio (FR), Logistic Regression (LR) and their ensemble method. For testing the accuracy of the FR model, test well locations were cross tabulated with the GRP map, and the highest well percentage was achieved in high groundwater recharge potential zone (37.39%). In the LR model, cross-tabulation results showed that 62.61% of testing wells were in the very high potential zones. The ensemble method of FR and LR revealed that 53.04% of test wells fall into the very high potential class. Hence, it can be assumed that LR predictions are more reliable than the FR model. To further validate the LR model and ensemble model, Receiver Operating Characteristics curve method was used. The Area Under the Curve (AUC) values for Success rate curve (SRC) and prediction rate curve (PRC) in LR method were 63% and 57% respectively. In ensemble method, the AUC values for SRC and PRC were 89% and 75%. These results indicate that the LR model is relatively poor estimator, whereas FR and LR ensemble method is relatively good estimator to evaluate groundwater recharge potential in Mulwathu Oya river basin.
 
 Keywords: Area under curve, Frequency ratio, GIS, Groundwater recharge, Logistic regression

A Naphthoquinoline-Dione-Based Cu2+ Sensing Probe with Visible Color Change and Fluorescence Quenching in an Aqueous Organic Solution.

Copper metal ions (Cu2+) are widely used in various industries, and their salts are used as supplementary components in agriculture and medicine. As this metal ion is associated with various health issues, it is necessary to detect and monitor it in environmental and biological samples. In the present report, we synthesized a naphthoquinoline-dione-based probe 1 containing three ester groups to investigate its ability to detect metal ions in an aqueous solution. Among various metal ions, probe 1 showed a vivid color change from yellow to colorless in the presence of Cu2+, as observed by the naked eye. The ratiometric method using the absorbance ratio (A413/A476) resulted in a limit of detection (LOD) of 1 µM for Cu2+. In addition, the intense yellow-green fluorescence was quenched upon the addition of Cu2+, resulting in a calculated LOD of 5 nM. Thus, probe 1 has the potential for dual response toward Cu2+ detection through color change and fluorescence quenching. 1H-NMR investigation and density functional theory (DFT) calculations indicate 1:1 binding of the metal ion to the small cavity of the probe comprising four functional groups: the carbonyl group of the amide (O), the amino group (N), and two t-butyl ester groups (O). When adsorbed onto various solid surfaces, such as cotton, silica, and filter paper, the probe showed effective detection of Cu2+ via fluorescence quenching. Probe 1 was also useful for Cu2+ sensing in environmental samples (sea and drain water) and biological samples (live HeLa cells).

Occurrence and path pollution of emerging organic contaminants in mineral water of Hranice hypogenic Karst

The Hranice hypogenic karst region includes urban, spa and agricultural areas and industry complexes that affect water quality in the region. Emerging organic contaminants (EOCs), especially pesticides and pharmaceuticals, are released into the complex aquatic system. These substances and their metabolites can affect aquatic and human life, as well as the regional development of the wider area traditionally associated with the spa. In this study, we conducted preliminary screening for pesticides and pharmaceuticals at 33 sampling sites and across different location types, including surface water, drainage water, a shallow well, groundwater and thermal karst water. Sampling occurred between February 2022 and June 2023. The results generally confirm that current land use is causing pollution in the karst system. The monitored substances were present in all water types, and in most cases the concentrations of pesticides were lower than those of their metabolites. Chloridazon desphenyl (DESPH) is the most widespread pesticide in surface, ground and hypogenic waters. Its concentrations in surface waters were 5.7 ng·L−1–2,230 ng·L−1, in groundwaters were 11.3 ng·L−1–1,490 ng·L−1 and in karst hypogenic waters 5.4 ng·L−1–378 ng·L−1. Diclofenac was the most widespread substance from the pharmaceutical group. Its concentrations ranged from 5.6 ng·L−1–549 ng·L−1 in surface waters, 8.4 ng·L−1–112 ng·L−1 in groundwaters and 5.1 ng·L−1–47.4 ng·L−1 in karst hypogenic waters. Directly in the karst hypogenic waters, the following EOCs were repeatedly detected: atrazine and its metabolites, simazin, metazachlor ethane sulfonic acid (ESA), metolachlor ESA, alachlor ESA, chloridazon DESPH, diclofenac, ibuprofen, azithromycin, bisphenol A and diethyltoluamide (DEET). The initial research hypothesis is that hydrothermal karst waters are of sub-recent age and deep circulation and, unlike surface and groundwaters, are not contaminated by recent pollutants. A certain component of these waters is therefore a shallow and shorter circulation.

Exploring the Correlation between Indoor Airflow Dynamics and the Accumulation of Polycyclic Aromatic Hydrocarbons using Spider Silk as a Passive Sampler

This study investigates the relationship between indoor air flow and accumulation of polycyclic aromatic hydrocarbons (PAHs) using spider silk as a passive sample Through a combination of computational fluid dynamics (CFD) simulations and experimental data, research di a significant difference under effective spider silk in controlled indoor air quality (IAQ). The study reveals significant variations in PAH accumulation within spider webs across different indoor environments, with stagnant airflow areas exhibiting higher PAH concentrations. Specific locations, such as corners and ventilation outlets, show consistent trends in PAH accumulation, underscoring the importance of strategic spider web placement for effective passive sampling. The research also highlights intriguing disparities in silk production among spider species and selective accumulation of different PAHs. The findings contribute to a nuanced understanding of indoor environmental dynamics and bio-monitoring outcomes, emphasizing the utility of spider silk as a reflective bio-monitor for assessing IAQ. This study provides valuable insights for future research endeavors aiming to enhance our understanding of indoor environmental quality and optimize passive sampling strategies.

Water Quality and Dissolved Organic Carbon Content in Agricultural Streams: Northern Nile Delta Region, Egypt

Sustainable development goals (SDGs) 2 (zero hunger), 6 (clean water and sanitation), and 15 (life on land) are related to the human-water-soil nexus. Soil organic carbon and nutrients can be removed and transported to waterways through runoff and drainage. The main goals of this study are to quantify the water quality for irrigation and assess the dissolved organic carbon (DOC) contents in streams in the northern Nile Delta, Egypt. A 4-year water quality monitoring program is accomplished by collecting 35 irrigation and drainage water samples per year from the study area. The measured water quality parameters are as follows: salinity, pH, Na, SAR, Cl, and NO3–N. In addition, the DOC content is accessed. The salinity hazard ranged from moderate, for most irrigation samples, to high and very high for drainage samples. All collected water samples have low to medium sodium hazards. Results indicate that average DOC contents in irrigation canals are 2.32 and 2.93 mg L−1 for the summer and winter, respectively. The respective means of DOC concentration in drainage canals for the summer and winter seasons are around 3.96 and 5.09 mg L−1. This study revealed significant differences in EC, pH, Na, Cl, and SAR, as water quality parameters, between irrigation and drainage canals. Additionally, the studied agroecosystem has seasonal variability in DOC concentration in irrigation and drainage canals between summer and winter. Overall, reusing drainage water for irrigation in the study area requires the selection of suitable crops and site-specific management.

Acetic acid stress response of the acidophilic sulfate reducer Acididesulfobacillus acetoxydans.

Acid mine drainage (AMD) waters are a severe environmental threat, due to their high metal content and low pH (pH <3). Current technologies treating AMD utilize neutrophilic sulfate-reducing microorganisms (SRMs), but acidophilic SRM could offer advantages. As AMDs are low in organics these processes require electron donor addition, which is often incompletely oxidized into organic acids (e.g., acetic acid). At low pH, acetic acid is undissociated and toxic to microorganisms. We investigated the stress response of the acetotrophic Acididesulfobacillus acetoxydans to acetic acid. A. acetoxydans was cultivated in bioreactors at pH 5.0 (optimum). For stress experiments, triplicate reactors were spiked until 7.5 mM of acetic acid and compared with (non-spiked) triplicate reactors for physiological, transcriptomic, and membrane lipid changes. After acetic acid spiking, the optical density initially dropped, followed by an adaptation phase during which growth resumed at a lower growth rate. Transcriptome analysis revealed a downregulation of genes involved in glutamate and aspartate synthesis following spiking. Membrane lipid analysis revealed a decrease in iso and anteiso fatty acid relative abundance; and an increase of acetyl-CoA as a fatty acid precursor. These adaptations allow A. acetoxydans to detoxify acetic acid, creating milder conditions for other microorganisms in AMD environments.

Research on Water Invasion Law and Control Measures for Ultradeep, Fractured, and Low-Porosity Sandstone Gas Reservoirs: A Case Study of Kelasu Gas Reservoirs in Tarim Basin

The exploitation of ultradeep, fractured, and low-porosity gas reservoirs often encounters challenges from water invasion, exacerbated by the presence of faults and fractures. This is particularly evident in the Kelasu gas reservoir group, located in the Kuqa Depression of the Tarim Basin. The complexity of the water invasion patterns in these reservoirs demands a thorough investigation to devise effective water control measures. To elucidate the water invasion patterns, a combined approach of large-scale physical modeling and discrete fracture numerical simulations was adopted. These models allowed for the identification and categorization of water invasion behaviors in various gas reservoirs. Furthermore, production dynamic analysis was utilized to tailor water control strategies to specific invasion patterns. The large-scale physical simulation experiment revealed that water invasion in gas reservoirs is primarily influenced by high-permeability channels (faults + fractures), and that the gas production rate serves as the key factor governing gas reservoir development. The range of gas extraction rates spans from 3% to 5%. As the gas extraction rate increases, the extraction intensity diminishes and the stable production duration shortens. On the basis of the changes in the water breakthrough time and water production rate, a 2% gas extraction rate is determined as the optimal rate for the model. The embedded discrete fracture numerical simulation model further supports the findings of the physical simulation experiments and demonstrates that ① this type of gas reservoir exhibits typical nonuniform water invasion patterns, controlled by structural location, faults, and degree of crack development; ② the water invasion patterns of gas reservoirs can be categorized into three types, these being explosive water flooding and channeling along faults, uniform intrusion along fractures, and combined intrusion along faults and fractures; ③ drawing from the characteristics of water invasion in various gas reservoirs, combined with production well dynamics and structural location, a five-character water control strategy of “prevention, control, drainage, adjustment, and plugging” is formulated, with the implementation of differentiated, one-well, one-policy governance. The study concludes that a proactive approach, prioritizing prevention, is crucial for managing water-free gas reservoirs. For water-bearing reservoirs, a combination of three-dimensional water plugging and drainage strategies is recommended. These insights have significant implications for extending the productive lifespan of gas reservoirs, enhancing recovery rates, and contributing to the economic and efficient development of ultradeep, fractured, and low-porosity gas reservoirs.

Nitrous oxide and methane production and consumption at five full-size denitrifying bioreactors treating subsurface drainage water

Nitrate (NO3−) removal in denitrifying bioreactors is influenced by flow, water chemistry, and design, but it is not known how these widely varying factors impact the production of nitrous oxide (N2O) or methane (CH4) across sites. Woodchip bioreactors link the hydrosphere and atmosphere in this respect, so five full-size bioreactors in Illinois, USA, were monitored for NO3−, N2O, and CH4 to better document where this water treatment technology resides along the pollution swapping to climate smart spectrum. Both surface fluxes and dissolved forms of N2O and CH4 were measured (n = 7–11 sampling campaigns per site) at bioreactors ranging from <1 to nearly 5 years old and treating subsurface drainage areas from between 6.9 and 29 ha. Across all sites, N2O surface and dissolved volumetric production rates averaged 1.0 ± 1.6 mg N2O-N/m3-d and 24 ± 62 mg dN2O-N/m3-d, respectively, and CH4 production rates averaged 6.0 ± 26 mg CH4-C/m3-d and 310 ± 520 mg dCH4-C/m3-d for surface and dissolved, respectively. However, N2O was consistently consumed at one bioreactor, and only three of the five sites produced notable CH4. Surface fluxes of CH4 were significantly reduced by the presence of a soil cover. Bioreactor denitrification was relatively efficient, with only 0.51 ± 3.5 % of removed nitrate emitted as N2O (n = 48). Modeled indirect N2O emissions factors were significantly lower when a bioreactor was present versus absent (EF5: 0.0055 versus 0.0062 kg N2O-N/kg NO3-N; p = 0.0011). While further greenhouse gas research on bioreactors is recommended, this should not be used as an excuse to slow adoption efforts. Bioreactors provide a practical option for voluntary water quality improvement in the heavily tile-drained US Midwest and elsewhere.

Geometry for low-inertia aerosol capture: Lessons from fog-basking beetles.

Water in the form of windborne fog droplets supports life in many coastal arid regions, where natural selection has driven nontrivial physical adaptation toward its separation and collection. For two species of Namib desert beetle whose body geometry makes for a poor filter, subtle modifications in shape and texture have been previously associated with improved performance by facilitating water drainage from its collecting surface. However, little is known about the relevance of these modifications to the flow physics that underlies droplets' impaction in the first place. We find, through coupled experiments and simulations, that such alterations can produce large relative gains in water collection by encouraging droplets to "slip" toward targets at the millimetric scale, and by disrupting boundary and lubrication layer effects at the microscopic scale. Our results offer a lesson in biological fog collection and design principles for controlling particle separation beyond the specific case of fog-basking beetles.

Water resources management in the context of the circular economy concept

The article examines the essence and main goals of the circular economy. The connection between the circular economy and the achievement of the goals of sustainable development has been studied. The positive effect of the introduction of the circular economy for the social, economic and ecological system was determined. Reducing the scarcity of natural resources, as well as the creation of durable goods, allows reducing the negative impact on the environment, which in turn stimulates innovation, which increases competitive advantages in international markets. The peculiarities of the development of circular economy models in developed countries are considered. The peculiarities of the economic category of water and its role in the economy are analyzed. The different roles of water emphasize its uniqueness and prove the difficulty of adopting a unified approach to it in the circular economy. The dynamics of indicators of the water capacity of Ukraine's GDP and volumes of return (waste) water discharged into surface water bodies were analyzed. It was determined that the rethinking of the urban water supply system through the principles of the circular economy and the goals of sustainable development will reduce the amount of polluted water and increase its reuse. It was determined that Ukraine is one of the least water-supplied countries in Europe, the annual runoff reserves available for use per person do not exceed 1,000 m3, while the GDP water capacity indicator remains sufficiently high and exceeds its target value. The dynamics of the indicator of the water capacity of the GDP of Ukraine has been analyzed, it has a tendency to decrease for the years 2015-2022. The characteristic problems of the functioning of urban water supply and drainage systems in the front-line territories and safer cities, where the number of internally displaced people has increased, are analyzed. It was analyzed that not all classic circular economy strategies can be applied to water. Strategies of the circular economy of water are considered and it is emphasized that rethinking is inherent in all water strategies. It has been analyzed that the implementation of the circular economy may face financial, bureaucratic and behavioral problems and regulatory, legislative, managerial and implementation obstacles. Keywords: circular economy, water resources, sustainable development, integrated management of water resources, state policy, goals of sustainable development, strategies, economic model, water supply and drainage system

The Influence of Environmental Sanitation on Stunting

Introduction: According to Pekanbaru City Health Department in 2019, there were 17.,67% of toddlers in Pekanbaru with poor nutritional status. Poor sanitation can trigger the emergence of infectious diseases that can reduce nutritional absorption in toddlers throughout the digestive process, resulting in stunting. The aim of this study was to analyze environmental sanitation influences on stunting. Methods: This research used case control study design. The case and control groups each received 30 samples. Independent variables include water source for sanitation, condition of latrines, condition of hand washing facilities with soap, condition of waste water drainage channels, management of household waste, type and condition of floors, presence of vectors and disease carrier animals, drinking water quality from biological conditions. The dependent variable was stunting. All data were collected using questionnaires that were asked directly to participants. Data analysis was performed by using the chi-square and multiple logistic regression tests. Results and Discussion: Water sources for sanitation, availability and condition of latrines, drinking water quality from biological terms influences on stunting (p-value &lt;0.,05). Multivariate tests show that, the drinking water quality from biological terms and water sources for sanitation had a probability value of 21% to cause stunting. Conclusion: The dominant factor influences on stunting is the drinking water quality in biological terms and water sources for sanitation.

Pore parameter selection for fused deposition modeling of gas diffusion layers in proton exchange membrane fuel cells

AbstractBecause of the global energy crisis, many researchers have focused their efforts on fuel cells. The gas diffusion layer (GDL) is a fundamental component of proton exchange membrane (PEM) fuel cells. The manufacturing procedures for traditional carbon‐based GDLs are sophisticated and energy‐intensive, and have design flexibility constraints, making it difficult to build complicated forms and structures. Additive manufacturing is widely used in a variety of fields, with the fused deposition modeling (FDM) technique being the most popular method. Prior to conducting systematic research on the printed GDLs, it is necessary to investigate the pore parameters with the support of FDM technique. In this research, the initial step involves material selection, FDM printer selection, and modeling. Subsequently, printing analysis and sample characterization are conducted to select an acceptable pore shape. A water drainage test determines the appropriate pore size, followed by additional tests for acceptable porosity range. The square pore shape is determined to be more suitable. A pore side length of 1.0 mm is identified. Furthermore, a suitable pore range of 10.9%–30.3% is identified. Next step, the printed GDLs will undergo further testing to investigate their suitability to be used in PEM fuel cells.

Drainage of storm water using the cadastral scale of agricultural land in Wadi Dala’ Hamdan (an archaeological study)

هدفت الدراسة الى إبراز وتوضيح أنظمة تصريف مياه الغيول، التي كانت تمثل عصب الحياة ونظام أساسي تمحور حوله المجتمعات اليمنية القديمة، ومنها مجتمع وادي ضلاع همدان، الذي قامت منشئاته مائية على انظمة ومقاييس متعددة في تصريف المياه وتوزعيها والتي تعود الى فترة ما قبل الإسلام، فمن أهمها نظام معرفة الوقت الزمني، ونظام التوزيع المباشر لمياه الغيول باستخدام القدم، والنظام المساحي للأراضي الزراعية التي استخدم فيها مقياس (اللبن الضهري)،هدفت الدراسة ايضاً الى توثيق ما تبقى من نظام الري القديم، المتوارث عبر الأجيال قبل اندثاره، وانقراضه بموت كبار السن الذين كانوا دولاً عليه. احتوت الدارسة على ثلاثة مباحث استعرض أولها الموقع الجغرافي والمادة التاريخية للوادي، واستعرض المبحث الثاني غيول وادي ضلاع همدان ونظام السقي فيها، وقد ركز المبحث الثالث على ذكر مقياس اللبنة الضهري وعلاقتها بنظام السقي. وقد اعتمد الباحث على المنهج النوعي في تنفيذ برنامج النزول الميداني الى مجتمع وادي ضلاع همدان، وإجراء المقابلات مع كبار السن الذين كانوا يقومون بتصريف مياه الغيول، وكذلك مع كبار السن من ملاك الغيول، بحيث كان يتم اثارة موضوع معين وترك الحوار مفتوح للمشاركين، شريطة أن الباحث سيد الحوار والهدف منها اتاحة الفرصة للتعبير عن بعض القضايا واثراء معلوماتها، من خلال تبادل الحوار بين المشاركين، واستحضار العاصفة الذهنية واستذكار بعضهم لبعض ما كان في الماضي، لان الاستهداف الفردي لكل شخص لم يجدي نفعاً، واستخدم الباحث بعد ذلك منهج التحليل لغرض التحقق من المعلومات. أهم النتائج التي تم التوصل إليها أن نظام الري في وادي ضلاع همدان، كان نظام قديم يعود الى فترات مملكة ذي مآذن وربما اقدم، بحكم نقوش المسند التي تم العثور عليها والتي تتحدث عن تنظيف بعض قنوات الري في الوادي، ومن النتائج ايضاً العثور على تسع منظومات مائية تزامن ظهورها في فترة معينة وذلك لتشابه منشاتها المعمارية والهندسية، وقد رافقها ظهور أنظمة وقوانين لتوزيع المياه باستخدام نظام الوقت الزمني ونظام حساب القدم والنظام المساحي (اللبن الضهري) الذي استخدم في حساب مساحة الأرض الزراعية وكذلك في تصريف مياه الغيول والذي بصدده أجرينا هذا البحث.

Ditch level-dependent N removal capacity of denitrification and anammox in the drainage system of the Ningxia Yellow River irrigation district

Drainage networks, consisting of different levels of ditches, play a positive role in removing reactive nitrogen (N) via self-purification before drainage water returns to natural water bodies. However, relatively little is known about the N removal capacity of irrigation agricultural systems with different drainage ditch levels. In this study, we employed soil core incubation and soil slurry 15N paired tracer techniques to investigate the N removal rate (i.e., N2 flux), denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA) rates in the Ningxia Yellow River irrigation district at various ditch levels, including field ditches (FD), paddy field ditches (PFD), lateral ditches (LD1 and LD2), branch ditches (BD1, BD2, BD3), and trunk ditches (TD). The results indicated that the N removal rate ranged from 44.7 to 165.22 nmol N g−1 h−1 in the ditches, in the following decreasing order: trunk ditches > branch ditches > paddy field ditches > lateral ditches > field ditches. This result suggested that the N removal rate in drainage ditches is determined by the ditch level. In addition, denitrification and anammox were the primary pathways for N removal in the ditches, contributing 68.40–76.64 % and 21.55–30.29 %, respectively, to the total N removal. In contrast, DNRA contributed only 0.82–2.15 % to the total nitrate reduction. The N removal rates were negatively correlated with soil EC and pH and were also constrained by the abundances of denitrification functional genes. Overall, our findings suggest that the ditch level should be considered when evaluating the N removal capacity of agricultural ditch systems.

Energy Production in Microbial Fuel Cells (MFCs) during the Biological Treatment of Wastewater from Soilless Plant Cultivation

The management of drainage water (DW), which is produced during the soilless cultivation of plants, requires a high energy input. At the same time, DW is characterized by a high electrolytic conductivity, a high redox potential, and is also stable and putrefaction-free. In the present study, the natural properties of drainage water and a biotreatment method employing an external organic substrate in the form of citric acid (C/N 1.0, 1.5, 2.0) were utilized for energy recovery by a microbial fuel cell (MFC). The cathode chamber served as a retention tank for DW with a carbon felt electrode fixed inside. In turn, a biological reactor with biomass attached to the filling in the form of carbon felt served as the anode chamber. The filling also played the role of an electrode. The chambers were combined by an ion exchange membrane, forming an H letter-shaped system. They were then connected in an external electrical circuit with a resistance of 1k Ω. The use of a flow-through system eliminated steps involving aeration and mixing of the chambers’ contents. Citric acid was found to be an efficient organic substrate. The voltage of the electric current increased from 44.34 ± 60.92 mV to 566.06 ± 2.47 mV for the organic substrate dose expressed by the C/N ratio ranging from 1.0 to 2.0. At the same time, the denitrification efficiency ranged from 51.47 ± 9.84 to 95.60 ± 1.99% and that of dephosphatation from 88.97 ± 2.41 to 90.48 ± 1.99% at C/N from 1.0 to 2.0. The conducted studies confirmed the possibility of recovering energy during the biological purification of drainage water in a biofilm reactor. The adopted solution only required the connection of electrodes and tanks with an ion-selective membrane. Further research should aim to biologically treat DW followed by identification of the feasibility of energy recovery by means of MFC.

Feasibility of utilizing recycled drainage water in agriculture using an analytical network process (ANP) and geographic information system (GIS)

AbstractUtilizing unconventional water for sustainable agriculture is a multi‐criteria process. Decision‐making in such problems is based on finding the value of various criteria using advanced methods, for example the analytic network process (ANP). ANP is usually preferred in cases where the criteria are not independent and have intra‐/intergroup relationships. Considering techno‐economic and environmental criteria, the ANP structure was used in this study to investigate the feasibility of utilizing Chapaghli drainage water in western Golestan Province, Iran, for cultivating tolerant and semi‐tolerant crops, including canola, barley, cotton and wheat, using GIS software. Irrigation water availability, techno‐economic distance and land suitability for cultivation were selected as techno‐economic criteria, while irrigation water quality, soil, plant sensitivity and aquifer vulnerability were selected as environmental criteria. The results show that canola is the best crop for cultivation with Chapaghli drainage water. This study provides a reliable decision‐making infrastructure related to the recycling of drainage water for various cultivars in an area where environmental hazards are minimized.

Phosphorus removal from agricultural tile drainage effluent with activated alumina in novel adsorption reactors.

Subsurface tile drains under agricultural field crops are a major source of phosphorus (P) discharge to aquatic ecosystems, contributing to the eutrophication of surface waters. Adsorption reactors for P removal from drainage water (P-reactors) could reduce P outflow from agricultural land but were rarely studied in cold, temperate climates. In our study, four low-cost P-reactors were installed in agricultural fields in south-central Québec, Canada. Activated alumina (AA) beads were used as P-adsorptive material, and the reactors were connected to tile drain outlets. Paired water samples (39 events) from reactor inlets and outlets were analyzed for P species and other physicochemical parameters during one calendar year to assess the P removal from tile drain effluent in the P-reactors. Collectively, the P-reactors retained approximately half (48%) of the total mass of P flowing through the tile drains, mostly (92%) as particulate P. The mass of AA beads adsorbed 11% of the dissolved-P fractions. Results are interpreted in the context of the field drainage area and will require adjustments to the P-reactor design to accommodate larger fields. The P-reactors remained structurally intact throughout all four seasons in a cold temperate climate, showing the potential of simple, inexpensive P-reactors to reduce P concentration in tile drain effluent.

Ecological Assessment Of Drainage Water Input On The Water Quality Of A Coastal Estuary, Mediterranean Coast Of Egypt

Ecological Assessment Of Drainage Water Input On The Water Quality Of A Coastal Estuary, Mediterranean Coast Of Egypt

Copper Speciation in Wine Growing-Drain Waters: Mobilization, Transport, and Environmental Diffusion

Copper (Cu) has been used to treat vines for a long time, which has led to its accumulation in vineyard soils. In the present work, the mobilization of copper from these soils and its transport, and diffusion outside the plots by drain water were investigated. For this, the distribution of copper between the dissolved and colloidal phases, and within the colloidal phase, of these waters was determined using an investigation strategy based on the coupling between a size separation technique, asymmetric flow field-flow fractionation, and several detectors. First, the total copper concentrations in water from different drains were monitored over a period of 2 years: Cu was mainly found in the fraction of &lt; 450 nm. Then, the distribution of copper on the size continuum was more closely studied in water from one of the drains, sampled over a winter period. Between 45 and 75% of Cu was found in the 2–450 nm colloidal fraction. The &lt;450 nm colloidal phase of the drain waters was found to be mainly composed of humic acids (~15 to 60 mg L−1) and clay-rich particles (~100 to 650 mg (Al) L−1). These particles also contained (hydr)oxides of iron and manganese. The concentrations of Fe and Mn were approximately 100 to 200 times lower than those of Al. The majority of humic acids had an apparent molar mass of ≤ 10 kDa. They were distributed along the size continuum: (i) in a population with an average size of ~20 nm, probably consisting of supramolecular entities, and (ii) associated with clay-rich particles with a size of ~120–200 nm. Copper was found to be complexed with humic acids and associated with clays via clay-humic complexes. Copper mobilization from the soil to the water and its transport to the drain water appeared governed by the soil humidity level and the rainfall.