scholarly journals Oxygen Regime Control in Water Body Amelioration

2019 ◽  
Vol 97 ◽  
pp. 05029
Author(s):  
Valery Borovkov ◽  
Ivan Karaichev
Keyword(s):  
Water Body ◽  
Water Mass ◽  
Practical Importance ◽  
Water Bodies ◽  
World Health ◽  
Polluted Water ◽  
Air Bubbles ◽  
Oxygen Regime ◽  
Discharge Velocity ◽  
Dimensionless Groups

An important aspect of water body amelioration is the control of the oxygen regime in water mass. Pollution of water bodies deteriorates their oxygen regime, and the natural inflow of oxygen through the free surface is not enough to compensate for oxygen consumption for pollutant oxidation. Water pollution by various substances causes damage resulting from a decrease in the ecological safety of urban water bodies. Data of World Health Organization (WHO) show that the contact of the population with polluted water bodies causes spreading of deceases, such as cholera, diarrhea, dysentery, hepatitis A, typhoid, and poliomyelitis, and creates considerable health risks. In this context, the artificial aeration of water mass with the use of aeration systems, which improve water quality, is gaining in importance. Most widespread among such aeration systems are diffused-air aerators, in which air supplied by a compressor passes through perforated diffuser plates. The size of the perforation is often chosen with no appropriate hydraulic substantiation. The size of the resulting air bubbles, no doubt, depends on the size of perforation holes; however, the available design relationships give contradictory results depending on the immersion depth of the diffuser plate and the working pressure, which determines air discharge velocity from diffuser plate perforations. This shows that the studies along this line are of scientific and practical importance. This article presents the analysis of the existing relationships for determining the size of air bubbles that form when air is pumped into water through nozzles of different diameters at different pumping rates; the analysis has shown the results of such calculations to differ considerably. Buckingham π-theorem was used to construct dimensionless groups, determining the relationship between the size of bubbles and the factors that govern the outflow of air into water. Dimensionless groups were used to obtain a formula for calculating the size of air bubbles at the aeration of water mass.

scholarly journals The landscaping of urban agglomeration park systems

Vestnik MGSU ◽  
2020 ◽  
pp. 294-306
Author(s):  
Aleksandra V. Ostyakova ◽  
Ekaterina V Pluisnina
Keyword(s):  
Water Body ◽  
Practical Importance ◽  
Pond Water ◽  
Water Bodies ◽  
Small Rivers ◽  
Urban Water ◽  
Normative Documents ◽  
Sources Of Pollution ◽  
City Water ◽  
Surrounding Areas

Introduction. Studying water body ecological problems and ensuring the necessary level of sanitary maintenance and landscaping of the reservoirs with the surrounding areas are relevant due to the inadequate environmental condition of a large number of urban water bodies and small rivers within settlements. Materials and methods. The review of the available normative documents and the carried-out actions on the improvement of city water objects is given. Based on the visual study of the state of the pond banks at the Karbyshev Park at the settlement of Nakhabino, Moscow region, water quality indicators, sources of pollution of the pond, the article concluded on the unsatisfactory ecological and aesthetic condition of this urban pond. The objective of this paper is to analyze the existing negative environmental factors affectig the water body and to propose an option of the site landscaping and further safe usage. Results. A description of the Karbyshev Park territory is given. Also, negative factors influencing the pollution of the pond banks, and the quality of pond water are specified. A proposal contains a list of necessary types of activities on cleaning and improving the pond bowl and surrounding territory under the condition of preservation of its ecosystem. As a result of the integrated assessment of the pond ecological state, a model of the urban water body was created, and a variant of its ecological reconstruction was proposed. Conclusions. The study is of practical importance for accounting and elimination of environmental problems of urban water bodies of the Central European Russia and proposals of measures for their improvement and reclamation.

scholarly journals Recognition of Water Colour Anomaly by Using Hue Angle and Sentinel 2 Image

2020 ◽  
Vol 12 (4) ◽  
pp. 716 ◽  
Author(s):  
Yelong Zhao ◽  
Qian Shen ◽  
Qian Wang ◽  
Fan Yang ◽  
Shenglei Wang ◽  
...  
Keyword(s):  
Remote Sensing ◽  
Water Body ◽  
Large Scale ◽  
Measured Data ◽  
Water Bodies ◽  
Polluted Water ◽  
Water Colour ◽  
Hue Angle ◽  
Anomalous Water ◽  
Sentinel 2

As polluted water bodies are often small in area and widely distributed, performing artificial field screening is difficult; however, remote-sensing-based screening has the advantages of being rapid, large-scale, and dynamic. Polluted water bodies often show anomalous water colours, such as black, grey, and red. Therefore, the large-scale recognition of suspected polluted water bodies through high-resolution remote-sensing images and water colour can improve the screening efficiency and narrow the screening scope. However, few studies have been conducted on such kinds of water bodies. The hue angle of a water body is a parameter used to describe colour in the International Commission on Illumination (CIE) colour space. Based on the measured data, the water body with a hue angle greater than 230.958° is defined as a water colour anomaly, which is recognised based on the Sentinel-2 image through the threshold set in this study. The results showed that the hue angle of the water body was extracted from the Sentinel-2 image, and the accuracy of the hue angle calculated by the in situ remote-sensing reflectance Rrs (λ) was evaluated, where the root mean square error (RMSE) and mean relative error (MRE) were 4.397° and 1.744%, respectively, proving that this method is feasible. The hue angle was calculated for a water colour anomaly and a general water body in Qiqihar. The water body was regarded as a water colour anomaly when the hue angle was >230.958° and as a general water body when the hue angle was ≤230.958°. High-quality Sentinel-2 images of Qiqihar taken from May 2016 to August 2019 were chosen, and the position of the water body remained unchanged; there was no error or omission, and the hue angle of the water colour anomaly changed obviously, indicating that this method had good stability. Additionally, the method proposed is only suitable for optical deep water, not for optical shallow water. When this method was applied to Xiong’an New Area, the results showed good recognition accuracy, demonstrating good universality of this method. In this study, taking Qiqihar as an example, a surface survey experiment was conducted from October 14 to 15, 2018, and the measured data of six general and four anomalous water sample points were obtained, including water quality terms such as Rrs (λ), transparency, water colour, water temperature, and turbidity.

Biological Nutrient Removal by Suspended Growth Systems

2020 ◽  
pp. 264-293
Author(s):  
Ezerie Henry Ezechi ◽  
Augustine Chioma Affam ◽  
Khalida Muda
Keyword(s):  
Water Body ◽  
Nutrient Removal ◽  
Aquatic Organisms ◽  
Point Sources ◽  
Water Bodies ◽  
Biological Nutrient Removal ◽  
Health Economy ◽  
Polluted Water ◽  
Suspended Growth ◽  
Polluted Wastewater

Nutrients contribute to the wellbeing of water bodies. However, excessive enrichment of water bodies by nutrients could harm aquatic organisms. Some of the severe environmental problems caused by nutrients on water bodies include eutrophication and algal bloom. In children, consumption of nitrate-polluted water causes methaemoglobinemia. Consumption of food irrigated with nutrient-polluted wastewater has been associated with several health implications. These nutrients primarily originate from point and non-point sources. Several biological-suspended treatment systems have been developed to reduce nutrients to acceptable limits prior to discharge into water bodies. These treatment systems are associated with several merits and demerits. This chapter explores the implications of water body enrichment by nutrients and their impact on health, economy, and environment. Furthermore, some suspended growth treatment systems applied for the treatment of nutrient polluted wastewater were explored.

Oxygen Regime of the Water Bodies as Main Factor of Different Metals Forms Migration within the System “Bottom Sediments - Water”

2009 ◽  
Vol 45 (2) ◽  
pp. 85-105 ◽  
Author(s):  
P. N. Linnik ◽  
O. V. Timchenko ◽  
A. V. Zubko ◽  
I. B. Zubenko ◽  
L. A. Malinovskaya
Keyword(s):  
Bottom Sediments ◽  
Water Bodies ◽  
Oxygen Regime ◽  
Main Factor

Development of Dialog System Model for Eutrophication Control between Discharging River Basin and Receiving Water Body – Case Study of Lake Sagami (Japan)

1989 ◽  
Vol 21 (12) ◽  
pp. 1821-1824
Author(s):  
M. Suzuki ◽  
K. Chihara ◽  
M. Okada ◽  
H. Kawashima ◽  
S. Hoshino
Keyword(s):  
Water Management ◽  
Water Quality ◽  
Expert System ◽  
River Basin ◽  
Water Body ◽  
Water Bodies ◽  
Quality Data ◽  
Pollution Load ◽  
Water Quality Data ◽  
Receiving Water

A computer program based on expert system software was developed and proposed as a prototype model for water management to control eutrophication problems in receiving water bodies (Suzuki etal., 1988). The system has several expert functions: 1. data input and estimation of pollution load generated and discharged in the river watershed; 2. estimation of pollution load run-off entering rivers; 3. estimation of water quality of receiving water bodies, such as lakes; and 4. assisting man-machine dialog operation. The program can be used with MS-DOS BASIC and assembler in a 16 bit personal computer. Five spread sheets are utilized in calculation and summation of the pollutant load, using multi-windows. Partial differential equations for an ecological model for simulation of self-purification in shallow rivers and simulation of seasonal variations of water quality in a lake were converted to computer programs and included in the expert system. The simulated results of water quality are shown on the monitor graphically. In this study, the expert system thus developed was used to estimate the present state of one typical polluted river basin. The river was the Katsura, which flows into Lake Sagami, a lake dammed for water supply. Data which had been actually measured were compared with the simulated water quality data, and good agreement was found. This type of expert system is expected to be useful for water management of a closed water body.

scholarly journals Downscaling MODIS Surface Reflectance to Improve Water Body Extraction

2015 ◽  
Vol 2015 ◽  
pp. 1-13 ◽  
Author(s):  
Xianghong Che ◽  
Min Feng ◽  
Hao Jiang ◽  
Jia Song ◽  
Bei Jia
Keyword(s):  
Surface Water ◽  
Water Body ◽  
Terrestrial Ecosystems ◽  
Water Area ◽  
Water Bodies ◽  
Tibet Plateau ◽  
Surface Reflectance ◽  
Discrimination Ability ◽  
Automated Method ◽  
Landsat 7

Inland surface water is essential to terrestrial ecosystems and human civilization. Accurate mapping of surface water dynamic is vital for both scientific research and policy-driven applications. MODIS provides twice observation per day, making it perfect for monitoring temporal water dynamic. Although MODIS provides two bands at 250 m resolution, accurately deriving water area always depends on observations from the spectral bands with 500 m resolution, which limits its discrimination ability over small lakes and rivers. The paper presents an automated method for downscaling the 500 m MODIS surface reflectance (SR) to 250 m to improve the spatial discrimination of water body extraction. The method has been tested at Co Ngoin and Co Bangkog in Qinghai-Tibet plateau. The downscaled SR and the derived water bodies were compared to SR and water body mapped from Landsat-7 ETM+ images were acquired on the same date. Consistency metrics were calculated to measure their agreement and disagreement. The comparisons indicated that the downscaled MODIS SR showed significant improvement over the original 500 m observations when compared with Landsat-7 ETM+ SR, and both commission and omission errors were reduced in the derived 250 m water bodies.

Minimal Dissolved Oxygen Requirements of Aquatic Life with Emphasis on Canadian Species: a Review

1975 ◽  
Vol 32 (12) ◽  
pp. 2295-2332 ◽  
Author(s):  
John C. Davis
Keyword(s):  
Dissolved Oxygen ◽  
Water Body ◽  
Physical Factors ◽  
Seasonal Temperature ◽  
Low Oxygen ◽  
Aquatic Life ◽  
Invertebrate Species ◽  
Oxygen Regime ◽  
Response Thresholds ◽  
Oxygen Requirements

This article reviews the sensitivity, responses, response thresholds, and minimum oxygen requirements of marine and freshwater organisms with strong emphasis on Canadian species. The analysis attempts to define low dissolved oxygen thresholds which produce some physiological, behavioral, or other response in different species.Oxygen availability is discussed with reference to seasonal, geographical, or spatial variation in dissolved oxygen. Factors affecting availability of dissolved oxygen include atmospheric exchange, mixing of water masses, upwelling, respiration, photosynthesis, ice cover, and physical factors such as temperature and salinity. Dissolved oxygen terminology is summarized and tables are included for both fresh and saltwater O2 solubility at different temperatures.Incipient O2 response thresholds are used in a statistical analysis to develop oxygen criteria for safeguarding various groups of freshwater and marine fish. These include mixed freshwater fish populations including or excluding salmonids, freshwater salmonid populations, salmonid larvae or mature salmonid eggs, marine anadromous and nonanadromous species. Criteria are based on threshold oxygen levels which influence fish behavior, blood O2 saturation, metabolic rate, swimming ability, viability and normal development of eggs and larvae, growth, circulatory dynamics, ventilation, gaseous exchange, and sensitivity to toxic stresses. The criteria provide three levels of protection for each fish group and are expressed as percentage oxygen saturation for a range of seasonal temperature maxima.Oxygen tolerances and responses of aquatic invertebrates to low oxygen are reviewed for freshwater and marine species according to habitat. No invertebrate criteria are proposed owing to the capacity for many invertebrate species to adopt anaerobic metabolism during low O2 stress. It is suggested that the criteria proposed for fish species will provide a reasonable safeguard to most invertebrate species. It appears likely, however, that a change in oxygen regime to one of increased O2 scarcity will probably influence invertebrate community structure.It is suggested that criteria for protection of aquatic life be implemented by groups of experienced individuals. The group should consider the natural oxygen regime for a specific water body and its natural variability, the aquatic life therein and its value, importance, relative O2 sensitivity, and the possibility of interactions with toxicants and other factors that may compound the stress produced by low O2 on aquatic life. Each water body and its aquatic life should be considered as a unique situation and criteria application should not encompass diverse areas, habitats, or biological associations as if they were identical.

Conceptual model for minimizing the risk of water pollution in the Kemerovo region

2020 ◽  
pp. 107-118 ◽  
Author(s):  
E. Yu. Kulikova ◽  
Ju. A. Sergeeva
Keyword(s):  
Water Pollution ◽  
Conceptual Model ◽  
Water Contamination ◽  
Coal Industry ◽  
Water Bodies ◽  
Polluted Water ◽  
Mining Operations ◽  
Mine Waters ◽  
Critical Limit

One of the problems of functioning of coal industry enterprises is the formation of mine waters, which are discharged into water bodies and cause their dangerous pollution. The total volume of water pumped by the enterprise includes up to 15 % for the recycling cycle, the remaining 85% is discharged to surface water bodies. As a result, the ecological balance of coal regions is disturbed, their sanitary and hygienic state on the environment worsens, and the quality of coal is reduced due to the intake of polluted water for technological operations. The volume of mine water contamination increases during mining operations at deeper horizons and in difficult mining and hydrogeological conditions. In turn, this leads to pollution and depletion of underground aquifers and the formation of environmental risk factors. In Kuzbass, all these factors contribute to the development of water crisis, since the state of surface reservoirs has already reached a critical limit. Especially dangerous is the process of liquidation of mines. Closing mines and sections disrupt natural water flows, resulting in all water from the aquifers going to deeper horizons. More pollutants enter the water, which poison the underground hydrosphere of the regions. The paper analyzes the pollutants entering the underground and surface hydro grid at coal-fired plants and offers a Conceptual model for minimizing the risk of water pollution.

scholarly journals The destruction of rennin by agitation: A case of catalysis at an air-liquid interface

1924 ◽  
Vol 106 (735) ◽  
pp. 97-117 ◽  
Keyword(s):  
Practical Importance ◽  
Liquid Interface ◽  
Test Fluid ◽  
Air Bubbles ◽  
Great Care ◽  
High Dilutions ◽  
Air Liquid Interface ◽  
Loss Of Strength ◽  
Toxin Formation

In a course of a series of investigations on the condition of maximum toxin formation by C. Diphtheria , undertaken by one of us (C. G. L. W.) (3), the question of “ripening” and of the deterioration of toxin in transport appeared to be colloidal phenomena in which interfacial action play a part. It was also noted that in the preparation of high dilutions of toxin for the Schick test great care is necessary when mixing the strong toxin with a diluent in order that no air bubbles passed through the solution. If this precaution was not taken the test fluid deteriorated in strength and led to untrustworthy results. Apart from the practical importance of the loss of strength of toxins, the process by which destruction was brought about was by no means clear, and it was considered of interest to investigate the phenomenon in more detail.

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