Main Canal Research Articles

Study on the influence of industrial structure optimization on water environment and economy: A case study of Changzhou city

Economic development and large amounts of industrial production have led to environmental deterioration. The assessment and prediction of water environment capacity (WEC) are crucial supports for water quality target management. Therefore, this study aims to improve WEC via changes in the industrial structure and to analyze the economic changes. For this purpose, the economic efficiency (EE), water use efficiency (WUE), and water treatment efficiency (WTE) are estimated by the EE–SBM (slack-based measure)–DEA (data envelopment analysis) model. Based on the proposed model, the industry is divided into three types: green enterprises, yellow enterprises, and red enterprises. Yellow enterprises and red enterprises are the major supervision subjects, and the spatial distribution of different environmental risks is identified. The WECs of the main canals are analyzed based on dynamic changes in the industrial structure by integrating the 0-D and MIKE11 models. The results showed that after adjusting the industrial structure, the maximum added values of the WEC of chemical oxygen demand (COD), total nitrogen (TN), ammonia nitrogen (NH3–N), and total phosphorus (TP) are 1,744.66 t/a, 536.14 t/a, 24.81 t/a, and 4.16 t/a, respectively. The results show that the canals (R40, R41, R20, R19, and R17) are overloaded with pollutants and indicate that TN is included as a water environment quality assessment target. Furthermore, after the optimization of the industrial structure, the loss of industrial output value is 174.44 million yuan, and the added value of the environmental economy is 232.12 million yuan. The findings provide important technical support for achieving industrial upgrading and sustainable development.

To the north: eDNA tracing of the seasonal and spatial dynamics of fish assemblages along the world's largest water diversion project

Extensive water diversion projects that have been increasingly installed worldwide transport essential water resources as well as a large number of biota. However, studies of the dynamic processes of such transport have been limited. The South-to-North Water Diversion Project of China is the largest manmade water diversion system ever constructed. Here, in a year-long project, we used environmental DNA (eDNA) metabarcoding to assess fish biodiversity and assemblage composition along the Project's 1277-km main canal, while also investigating the temporal, spatial, and functional trait drivers of changes in the fish assemblages. Together, 45 fish taxa were detected, with substantial compositional variations between seasons. The number of detected species typically dropped upon entering the canal but remained relatively constant along the canal's length. Spatial variations in fish assemblages were generally dominated by the turnover component over nestedness, and a positive spatial autocorrelation of qualitative assemblage composition was detected within 80 km in all seasons. Furthermore, several functional traits, such as smaller body size, invertivorous diet, rheophilic living, and lithophilic and demersal spawning, were positive predictors of fish presence along the length of the canal and they may boost species chances of introduction to the recipient areas. Our results provide crucial information for ecological management of diversion projects and have key implications for modelling and predicting foreign species invasion through water transfers.

Расчетное исследование потерь воды из необлицованных каналов с учетом геолого-почвенных особенностей севера Калмыкии

Purpose: carrying out filtration calculations of the main canals (MC) and comparison (comparative analysis) of the obtained values. Materials and methods. The object of study is the water supply network of the Sarpinsky irrigation and watering system (SOOS) in the North of Kalmykia. The initial data for the study were the field survey data of the system canals, as well as materials for official use obtained in the operating organization. When performing filtration calculations, the physical and geographical features of the irrigation network location area were taken into account and the method for calculating backed fil-tration from a canal (in an earth channel) was used under conditions of a steady movement of the seepage discharge. The calculation was based on the application of the filtration resistance method. Results and discussion. Taking into account the features of the geological and soil conditions of the northern regions of Kalmykia, the calculated values of filtration losses from the MC system were determined, which amounted to 2.7–6.51 l/(day sq. m) for the calculated sections of the MC VR-1 and 5.46 l/(day sq. m) – for MС R-1. Comparison of the data ob-tained for the MC SOOS with the results of studies of unlined sections of the Great Stavropol Canal, laid in the similar geological conditions, confirmed the authors' assumption that the values of seepage flow rates from the MC were significantly affected by the presence of clay soils at the canal bottom. Conclusions. As a result of the research, it was found that the value of filtration losses from MC SOOS is significantly affected by the geological and soil features of the system location area, and in particular the low permeability of mantle loams, as well as the presence of impervious Khvalyn clays of marine origin. The studies of other authors have confirmed that the close occurrence of these clays to the day surface contributes to flooding and land salinization, this was not taken into account when developing irrigation in the north of the region.

WAYS OF RATIONAL USE OF WATER RESOURCES IN THE CONDITIONS OF POST-WAR RECLAMATION SYSTEMS IN THE SOUTH OF UKRAINE

After the explosion of the Kakhovka hydroelectric power station, the problem of restoring damaged areas of reclamation systems and rational use of water resources in the de-occupied territories of southern Ukraine is extremely relevant today. An integral part of solving this problem is the theoretical justification and assessment of filtration losses in damaged areas of open drainage channels with interception of this flow by drainage structures. This study presents a methodology for calculating the filtration losses of water from a main canal that runs in an excavation with a channelside pipe drainage. The calculations take into account the pressure drop on the canal lining. The filtration water losses per linear metre of the main channel of the Ingulets irrigation system were determined, taking into account the filtration resistance of the screen, which is economically feasible to restore from local water-resistant natural materials. In this case, the channel drainage performs two functions. Firstly, it prevents flooding of the territory; secondly, it is possible to use innovative technologies to return part of the filtration effluent for use in various water supply sectors of the region. The research results will allow us to further develop recommendations for effective engineering protection of water resources from pollution and depletion in this region.

Бұланды (Баланды) фортификациясын зерттеу нәтижелері

The article considers the fortification of the Balanda I fortress, which is located at the ancient Syr Darya delta, where the agricultural Chirikrabat archaeological culture was widespread in the second half of the I millennium BC. Balanda Fortress is the center of a small agricultural oasis of the IV+II centuries BC, which was based on the main canal, between the channels of the Inkardarya and Zhanadarya lower reaches of the Syr Darya, as a whole. The center of the settlement and the entire oasis was the fortified manor-fortress of Balanda. During the field works of Chirikrabat expedition in 2007-2014, it was possible to identify and partially reconstruct the constructions of defense. Based on the data obtained, it is possible to distinguish at least 2 main periods of the construction of fortress walls, which, in turn, are divided into stages. The system of fortification revealed during the excavations of Balanda I seems to be quite archaic. The corners were protected by semicircular towers, which were a solid monolith of brickwork on a base-a plinth made of dense clay-pakhsa, to which a pakhsa platform with a width of 1.3-1.4 m and a height of no more than 1 m was attached from the inside. The long walls of the fortress were also flanked by semicircular towers. The walls and the protruding towers were cut with arrow-shaped loopholes. Based on archaeological data, the Balanda Fortress was a large fundamental building

ДИНАМИКА ИРРИГАЦИОННОГО КАЧЕСТВА ОРОСИТЕЛЬНОЙ И ДРЕНАЖНО-СБРОСНЫХ ВОД НИЖНЕ-ДОНСКОЙ ОРОСИТЕЛЬНОЙ СИСТЕМЫ В 1972 И 2019–2021 ГОДАХ

Purpose: to assess the dynamics of the irrigation quality of irrigation water from the main canal and drainage wastewater (DWW) from the outlet collectors using the example of the Nizhne-Don irrigation system (NDIS) to justify the sustainability of their environmental safety. Materials and methods. The objects of the study were DWW from the TsS, K-3, LS-2 and MKL-7 collectors, water from the Tsimlyansk reservoir supplied to the Nizhne-Don main canal (NDMC). The subject of the study was the hydrochemical indicators of the DWW in 1972 and 2019–2021, and the comparative irrigation characteristics of the waters. Results. Comparison of water irrigation characteristics from NDMC in 1972 and 2019 showed an increase in sulfate salinity by about 35 %. The irrigation coefficient according to H. Stebler (Ka) has decreased from 43.24 to 28.15 since 1972, while the irrigation water quality from NDMC remains good (Ka > 18). In 1972, the average value of the irrigation coefficient (Ka) of DWW during the irrigation period in the K-3 collector was 2.98, in LS-2 – 4.14, in TsS – 5.54, in MKL-7 – 22.96. In 2019–2021 – 10.44; 14.85; 12.62; 11.61 respectively. Conclusions. The irrigation quality of the Don irrigation water from the NDMC has now deteriorated compared to 1972 by 1.54 times. Over the fifty-year period of operation of the NDIS, the irrigation quality of the DWW in the collectors K-3, LS-2 and TsS increased by 2–3.5 times. Irrigation water quality in the MKL-7 collector decreased by 2 times. It has been proven that the use of fresh irrigation water for irrigation contributes to a sustainable increase in the environmental safety of DWW. The need to reuse DWW for irrigation should be decided at the regional level based on the economic feasibility of the cost of cleaning and transporting water to the irrigation system.

Comparative Efficacy of Different Irrigant Activation Techniques for Irrigant Delivery Up to the Working Length of Mature Permanent Teeth: A Systematic Review and Meta-Analysis

This systematic review aims to establish whether various irrigant activation techniques (IATs) result in greater penetration of irrigant up to the working length. The MEDLINE, Scopus and Cochrane Library electronic databases were searched to determine the difference in irrigant penetration depth in the main canal following the use of manual dynamic activation (MDA), sonic irrigation (SI), passive ultrasonic irrigation (PUI), and apical negative pressure irrigation technique (ANP) in comparison with conventional needle irrigation technique (CNI) in mature permanent teeth. Meta-analysis was performed for straight canals as well as curved canals in addition to subgroup analyses for a) Individual IATs in comparison with CNI, b) Comparison of PUI v ANP and SI v ANP in the straight canals, c) comparison of different IATs performed in straight and curved canals. The outcome was presented as effect size: standardized mean difference (SMD) and percentage difference (% diff) of irrigant penetration up to the working length (WL) alongside 95% confidence intervals using chi-square analysis. Of the 840 records screened, 20 studies were included in the systematic review and 17 studies were included in the meta-analysis. It revealed IATs had significant improvement in irrigant delivery up to the WL in straight (% diff: 51.94%, 95% CI: 39.20-64.67%) and curved canals (SMD: 1.08, 95% CI: 0.64-1.52) over CNI. The subgroup analysis revealed ANP was the most effective and significant technique followed by PUI, SI and MDA techniques in straight canals (% diff: 91.70%, 95% CI: 75.63-107.77%) and curved canals (SMD: 1.45, 95% CI: 0.77-2.13). IATs improve irrigant penetration when compared to CNI technique. In both straight and curved canals, ANP is the most effective in delivering the irrigant up to the WL followed by PUI, SI and MDA techniques. Hence adaptation of recent IATs in routine endodontic practice is recommended. (EEJ-2022-03-036).

Phytotesting of water quality in the main canal on the left bank of the Kherson region after the Kakhovka hydroelectric power station dam was blown up

Phytotesting of water quality in the main canal on the left bank of the Kherson region after the Kakhovka hydroelectric power station dam was blown up

Анализ возможности использования программируемых контроллеров при управлении водораспределением в Донском магистральном канале

Purpose: to analyze the possibilities of using programmable logic controllers (PLC) in water distribution management in the Don Main Canal. The work is an analytical study based on the principles of automation and optimization of water resources control. Discussion. The architecture of the control system, including programmable logic controllers, network modules and water level sensors in the main canal is discussed. The main attention is paid to justifying the use of PLC in the design and development of a water distribution control system, which allows control and regulate the water level in the channel using the upstream control scheme. The software offers possibility for monitoring water parameters, calculating optimal values and automatic adjustment of control signals. The advantages of using PLC in water distribution control system, including high flexibility, reliability and the possibility of easy integration with other systems are also analyzed. The methods of PLC setting, regulator optimization and energy management to achieve efficient and economical water resources management are described. The research confirms the effectiveness and applicability of using the programmable controllers in water distribution management system in the Don Main Canal. Conclusions: the results obtained make it possible to increase the efficiency of water resources use, reduce energy consumption and ensure stable control of water level in the irrigation canal.

Assessment of post-liquefaction potential in soil displacement on irrigation canal reconstruction project in the Jono Oge and Lolu area, Central Sulawesi, Indonesia

A seismic event of magnitude 7.5 Mw took place in Central Sulawesi in September 2018, marking a significant occurrence in the geological hazard chronicles of Indonesia. The occurrence of liquefaction subsequent to the earthquake significantly damaged the water resource infrastructure in the Sigi Regency. This study aims to evaluate the possible soil displacement resulting from re-liquefaction events occurring in the main irrigation canals in the Jono Oge and Lolu regions. The study used semi-empirical and finite element analysis to compute the lateral displacement index and reconsolidation settlement within the designated study region. The examination of soil displacement is conducted under various groundwater level scenarios, utilizing the most recent soil investigation conducted in 2021. The findings of the study indicate that raising the groundwater level to -3.5 meters will result in significant soil and irrigation canal damage. In the future, it is suggested that limiting the groundwater level below -11 meters in the primary irrigation canal area might effectively mitigate soil lateral displacement and settlement.

Programs with programs to take water from the river without dams

In the arid areas of the river itself, the direction of flow is characterized by changes depending on its hydrological regime. As a result of these changes, the flow can be branched into several streams and the flow can be distributed differently in terms of quantity. As the river passes through lightly washed soils, these streams have different depths, and its hydraulic elements and river morphometry can vary at different intensities. Changes in hydraulic resistance as a result of such changes can affect the water permeability of streams. It should be noted that, depending on the form of morphometry, the roughness of the stream and the shoreline may vary at the same constant size of depth. This could be the Karshi Main and Amu Bukhara Mashina canals, which receive the most dam-free water from the Amudarya to the irrigated areas of the Republic of Uzbekistan. In these catchment areas, rapid washing of riverbeds, uneven distribution of flow velocity, and the constant distance of the stream from the dam intake facility away from the main intake facility complicate operating conditions and reduce the amount of water required to enter the canal during the growing season.

Terelabrus toretore sp. nov. (Perciformes: Labridae), a New Species of Striped Hogfish from Tahiti, with Range Extensions for Two Congeners.

A new labrid fish, Terelabrus toretore sp. nov., the fifth species within the genus, is herein described from two specimens collected at a depth of 140 m from a mesophotic coral ecosystem in Tahiti, French Polynesia. Terelabrus toretore sp. nov. is characterized by having 43-44 scaled rows in longitudinal series; 42 pored lateral-line scales; 5+10 gill rakers; 10 scale rows below the lateral line; 8 posterior branches on the main supratemporal sensory canal; a relatively long snout (snout length 9.6-9.7% SL), and a coloration consisting of a yellow caudal fin and a wide, red, mid-lateral stripe with no blotching, the space above which is white anteriorly, becoming predominantly yellow from beneath the dorsal fin to the caudal peduncle. In addition to describing this new species, we document the first record of Terelabrus rubrovittatus from the Republic of Marshall Islands, and the first record of Terelabrus zonalis from Australia, along with the first description of its coloration. We present a molecular phylogeny of the genus based upon mitochondrial cytochrome c oxidase subunit I (COI) DNA sequences.

Diagnostics of pumping units of pumping station of machine water lifting

The purpose of diagnostics is to determine the operability of the pumping units of the pumping station of the machine water lifting at a given time and to identify defects in their components. For this reason, the article presents diagnostic issues for pumping stations No. 1 - No. 6 of the Karshi main canal, designed and commissioned in 1965-1976, where 6 pumping units of the OPV11-260EG type with electric motors of the VDS-375/130-24 type are installed, vertical pumping units, shaft power – 8010 kW, rated power electric motor – 12500 kW, voltage – 10.0 kV, stator current – 825.0 A, maximum permissible temperature of the stator winding – 120 OC, bearing temperature – no more than 70 OC. Diagnostics of the main equipment involves the prompt detection of malfunctions as a result of processing sensor readings of the standard monitoring system, sensor readings are entered manually once a day, and data from monthly and special tests. Technological algorithms of vibration and thermal diagnostics are similar to those developed for vertical pumps installed at thermal power plants, the processes being diagnosed in which are similar to the processes occurring in pumping units of a pumping station. Taking into account the above tasks, algorithms have been developed for diagnosing the main components whose condition affects the performance of the pumping unit: the upper bearing, the upper crosspiece, the stator winding and core, the upper and lower guide bearings, and the electric motor bearing. Possible malfunctions of pumping unit components and ways to eliminate them are given.

Influence of concentration, irrigation method, and root canal third on intratubular penetration of sodium hypochlorite - a broad statistical analysis.

The permanence of microorganisms in the root canal system represents the main cause of endodontic failure. Considering the impossibility of effective action of the endodontic files in ramifications of the main canal and mainly inside the dentinal tubules, a better understanding of the irrigation dynamics to enhance endodontic prognosis is essential. Objective: To evaluate the depth of intratubular penetration values of sodium hypochlorite (NaOCl) (dependent variable) by comparing different concentrations, methods of irrigation, and root canal thirds (independent variables) and to investigate the existence of interactions among them, capable of influencing the dependent variable. 40 roots from extracted human maxillary central incisors were stained and instrumented according to four irrigation protocols (n. 10): conventional irrigation (CI) at each use or change of instrument, and final irrigation with 5ml of 2.5% or 5.25% NaOCl, with or without passive ultrasonic irrigation (PUI), respectivelly. Measurements based on stereomicroscopic images were obtained, and the data were subjected to statistical analysis (p< 0.05). The highest depth values of intratubular penetration of NaOCl were observed in the cervical third, at 5.25%, and by PUI. When only two independent variables were analyzed in association, the highest penetration depth values of NaOCl were obtained at 5.25%, regardless of irrigation method, at 5,25%, in the cervical third, and; in the cervical third, despite of irrigation method. Considering the three independent variables simultaneously, the highest depth values of intratubular penetration of NaOCl were observed in the cervical third, at 5.25%, no matter the irrigation method. The interaction between the independent variables on the penetration depth values of NaOCl was only confirmed considering the irrigation method and root canal third. Intratubular penetration of NaOCl was influenced by the three independent variables individually and when the irrigation method and root canal third were considered simultaneously. Key words:Dentinal tubules, Depth, Disinfection, Irrigation, Root canal system, Sodium hypochlorite.

Investigation of the interaction of hydraulic parameters of the channel in the filtration process

One of the most important and complex issues in the design of soil drainage channels is the issue of correct accounting of the filtration process. It is necessary to take into account hydraulic parameters and soil composition of existing channels in order to reduce filtration flow rate in ditches with uncoated soil. The article shows how to choose its theoretical basis for reducing the filtration flow rate correctly. Hydraulically convenient design is one of the current problems in the design of canals. This can be achieved by reducing the wet perimeter of the channel to reduce the filtration process in the channel. The article recommends that measures to reduce the filtration process be implemented during the construction or reconstruction of canals, without dismantling and rehabilitating existing canals. Field research was conducted on the North Fergana main canal. In order to study the filtration processes, measurement works were carried out on the PK 396+00, PK 497+01, PK 688+7, PK 692+6, PK 694+6, PK 697+00 pickets crossing the 2-section of the channel in the city of Namangan. In addition, the article developed recommendations on the methods and procedures for the application of bentonite clay from the Lagon betonet clay deposit of the Fergana region to the bottom of the channel in order to reduce the filtration process that occurs in the canal area. According to the results of the study, in the range from PK 411 + 00 to PK 426 + 74, filtration consumption was higher than other pickets.

Оценка гидравлической шероховатости русла магистрального канала

The purpose of the study was to determine the roughness coefficient of the main channel bed BP-1 of the Sarpinskaya watering-irrigation system (SWIS) and to compare the data obtained with the normative values. The materials for performing the calculations were: an explanatory note to the project of the second stage of the construction of the SWIS, passports of the main and inter-farm channels of the system (2015), a technical report of the operating organization for 2021, data of full-scale measurements of the depths and velocities of the water flow in the considered alignment using the «speed-area» method, the results of full-scale surveys of the water supply network and HTS SWIS, as well as data from GIS maps and literary sources. The methodology for calculating the elements of the live section of the channels took into account the recommendations of SP 100.13330.2016. The calculation of the roughness coefficients of the channels was carried out using known dependencies, including the Chezy formula, the Manning equation, the dependencies of I.I. Agroskin and N.N. Pavlovsky. The elements of the living section are determined and the values of the roughness coeffi cient in the considered alignment of the main channel are obtained. At the same time, the calculated values of the roughness coefficient obtained have good convergence (the deviation of the results does not exceed –2.8%). However, the obtained values exceed the normative value of the roughness coefficient by 1.6-1.64 times, which is explained not only by the overgrowth of the channel bed with aquatic vegetation, but also by the peculiarity of the shape of the cross-section of this channel, which in the area under consideration has a signifi cant width along the bottom. The calculated values of the roughness coeffi cient obtained indicate the overgrowth of the main canal bed, which was confi rmed during field surveys of the water supply network of this canal in the spring of 2022. In view of this, it is necessary to carry out preventive measures in a timely manner aimed at reducing the additional hydraulic resistance caused by overgrowth of the riverbed with vegetation.

Experimental evaluation of the throughput of the supply channel of pumping stations

The article experimentally studied the dynamics of sediment inflow into the fore chambers of pumping stations, revealed the intensity of silting, which affects the reliability and operation of the pumping station, and developed recommendations for improving its efficiency. The hydraulic parameters of the flow were evaluated by increasing the culvert capacity of the canal bed and ensuring a guaranteed flow of water to the pumping station with a minimum amount of sediment. The purpose of this work is to assess the state of its culvert capacity based on the results of field studies, which represent the water supply from the pumping station of the Karshi main canal.

Теоретическое обоснование параметров телескопического водовыпускного сооружения с круглоцилиндрическим поплавком

The purpose of the research is to improve the design of a water outlet, to calculate a telescopic outlet with a round-cylindrical float and determining the diameter of the movable box float with the given parameters, which should ensure the reliability of its static position in all possible hydraulic modes of operation as a spillway with a round-cylindrical cap with a movable position of the crest, depending from the water level in the receiving main canal. The article presents the developed design of the outlet structure of the overflow outlet structure of the telescopic type, which has a simple design, reliability in operation, structural design with minimal hydraulic losses. The paper shows the results of theoretical studies of the proposed design of a telescopic outlet structure, three variants have been considered for the operation of the movable box, from the above calculations, the defining diameter of the float is the mode with water overflowing through it when the maximum flow rate of the pipeline is supplied. The following calculated diameters of the float were obtained; dfl o = 0.1279 m, dfl = 0. 0808 m and dfl t = 0.315m. It is possible to use standard PVC pipes, the nearest larger standard outer diameter is d = 0.355 mm. considering the simplicity of the design of the telescopic type water outlet, it can be manufactured in the conditions of mechanical workshops of construction organizations.

Methods of channel calculations to improve the operational mode of main canals

The article discusses solutions to improve the operational mode of the canal with an increase in throughput by means of self-washout, while maintaining the morphometric favorable stable cross-section of the canal for further reliable water supply of suspended crop areas. Taking into account the characteristics of the course of channel deformation processes, we have considered the modern dynamics of channel flows for accurate calculation of channel deformations using the systems of equations of one-dimensional flow in the deformable Saint-Venant channel or two-dimensional shallow water equations (planned task), which will give a positive result for the operational mode of the main canals.

Practice of permanent presence and equipment of Karshi main canal

The research aims to develop new energy-saving modes of operation of the Karshi main canal with a cascade of pumping stations designed to irrigate the virgin lands of the Karshi steppe with water from the Amudarya River. The article discusses some calculation methods and control parametric tests of pumps by measuring the main parameters: flow, pump head, electric motor power, NPSH, and pump efficiency. Normal operation of pumping stations requires compliance with cavitation conditions of pumps of certain levels downstream. The authors have given recommendations on the use of a new floodwater design and obtained the flow's main characteristics in the section under consideration, taking into account the hydrometric characteristics. Further work continues to improve the scheme of water supply facilities by introducing new means of regulating the operation of pumping station elements into the scheme.