Dissolved Oxygen Levels In Water Research Articles

An evolutionary approach to dissolved oxygen mathematical modeling: A case study of the Klamath River

Aquaculture has emerged as a crucial sector in many countries. In the Recirculating Aquaculture System (RAS), Dissolved Oxygen (DO) levels are critical to the health of aquatic animals. As DO sensors are costly, a number of studies have proposed a soft sensor technique utilizing machine learning for estimating DO levels in water. However, the existing research work mainly focuses on black-box approaches, which do not provide numerical analysis between the DO levels and the related parameters. To solve this issue, a sequential Genetic Programming (GP) approach with an evolutionary refinement method is proposed to generate a mathematical expression that represents DO levels in water. In particular, a coarse mathematical model is generated using GP and subsequently fine-tuned using the Covariance Matrix Adaptation Evolution Strategy (CMA-ES). As a study case, the Klamath River dataset is used to generate the model. The evaluation of our proposed method uses datasets from both the Klamath River and the Fanno Creek. Two models are generated in this paper; one model uses six features, while the other only employs three. The results indicate that the model with six features exhibits relatively higher accuracy. However, it is worth noting that a smaller dataset of features is also capable of achieving generalization of the model.

Effect of chitosan on common carp (Cyprinus carpio) fry growth performance, feed utilization and nutriphysiological status

The aim of research was to analyse the impact of chitosan supplementation (1% and 2% doses) on the nutriphysiological status (selected blood biochemical indicators, the microstructure of the intestine and liver and the mineral profile in the meat of common carp (Cyprinus carpio) fry (average 63 ± 4.9 g). The experiment was carried out with four replications per treatment, with 48 fish per tank in an open flow system. The average water temperature during the experiment was 20.7 °C, with a range from 18.0° to 22.8°C. The average water dissolved oxygen level was 4.6 mg dm−3 with a range of 4.0–6.2 mg dm−3. Experimental diets contained crude protein (37.5%) and crude fat (8.9%). There were no statistically significant differences between groups within the analysed growth and feed utilization parameters. As the blood analysis showed, chitosan supplementation significantly influenced (P < 0.05) the levels of total cholesterol (TCH), low-density lipoprotein (LDL), alkaline phosphatase (ALP), iron (Fe) and phosphorus (P). The 2% chitosan led to a reduction in the Fe level in the meat, and dietary supplementation with chitosan at both doses caused a significant increase (P < 0.05) in the concentration of Cu in this tissue. This confirms the properties of chitosan as a dietary fibre that inhibits the absorption of Fe in the intestine by reducing its bioavailability for mucosal cells. A significant increase (P < 0.05) in crypt depth and muscular layer thickness was observed with the increase in dietary chitosan. Histopathological examination of the liver showed significant differences in hepatocyte vacuolization between groups supplemented with 2% chitosan and the control. Only mild to moderate pathological changes and no severe pathological changes were observed between the experimental groups. The obtained results indicate that the chitosan used in the experiment showed both prebiotic and dietary fibre properties.

Aeration and dissolution behavior of oxygen nanobubbles in water

HypothesisNanobubbles (NBs) in water elicit unique physicochemical and colloidal properties (e.g., high stability and longevity). Aeration kinetics and dissolution behavior of oxygen (O2) NBs are assumed to be bubble size dependent. ExperimentsAs an indicator for aeration efficiency, volumetric mass transfer coefficient (KL·a) was assessed by measuring the dissolved oxygen (DO) levels during aeration using O2 NBs with different sizes. Mass transfer coefficient (KL) was estimated by correlation analysis. Moreover, a modified Epstein-Plesset (EP) model was developed to predict the dissolution behavior by monitoring the DO and size changes during the dissolution of O2 NBs in water. FindingsA higher rate of DO increase and a higher equilibrium DO level were both observed after aeration with NBs that present higher surface areas for the mass transfer of O2 and a higher vapor pressure of O2 to drive the partitioning equilibrium. Dissolution kinetics of O2 NBs were highly dependent on the initial bubble size as indicated by the changes of bubble size and DO. Smaller NBs raised up DO faster, whereas larger NBs could lead to higher equilibrium DO levels. Moreover, the rate of DO decline and the quasi-steady DO levels both decreased when the dilution ratio increased, confirming that O2 NBs dictates the DO level in water. Finally, the dissolving NBs may either swell or shrink according to the model prediction.

Stress relieving potential of two plant-based sedatives in the transport of juvenile tambaqui Colossoma macropomum

The objective of this study was to investigate the effects of waxy extract of Spilanthes acmella and essential oil (EO) of Nectandra grandiflora on secondary stress responses of tambaqui Colossoma macropomum transported for up to 10 h. Fish were packed in plastic bags and shipped for 2, 6 and 10 h with or without anaesthetics added to the transport water. Whole blood was collected from the caudal vasculature before and after transport and several haematological variables were measured. No mortalities were observed after transport. Attenuation of secondary stress responses was observed with the use of N. grandiflora EO after 6 h transport based on lower glycaemia and no alteration of blood Na+ concentrations after transport compared to reference values of non-transported fish. Furthermore, dissolved oxygen levels were still maintained in the water after transport for 10 h with N. grandiflora EO compared to water of non-transported fish. While no clear advantages were observed with the use of S. acmella extract at 2 mg L−1 after transport, the use of N. grandiflora EO at 30 μL L−1 should be considered for the transport of C. macropomum for it seems to provide a sparing effect on the water dissolved oxygen levels and an improved physiological condition after transport.

A Survey on the Analysis of Dissolved Oxygen Level in Water using Data Mining Techniques

Data Mining (DM) is a powerful and a new field having various techniques to analyses the recent real world problems. In DM, environmental mining is one of the essential and interesting research areas. DM enables to collect fundamental insights and knowledge from massive volume of environmental data. The water quality is determining the condition of water in the environment. It represents the concentration and state (dissolved or particulate) of some or all the organic and inorganic material present in the water, together with certain physical characteristics of the water. The Dissolved Oxygen (DO) is one of the important aspects of water quality. The DO is the quantity of gaseous oxygen (O2) incorporated into the water. The DO is essential for keeping the water organisms alive. The amount of DO level in the water can be detected by various methods. The data mining techniques are properly used to find DO Level in the different types of water. A number of DM methods used to analyze the DO level such as Multi-Layer Perceptron, Multivariate Linear Regression, Factor Analysis, and Feed Forward Neural Network. This survey work discusses about such type of methods, particularly used for the analysis of DO level elaborately. Finally, this research suggests the best DM method to find DO level in water by means of a comparative analysis.

Granulomatous enteritis in rainbow trout (Oncorhynchus mykiss) associated with soya bean meal regardless of water dissolved oxygen level

This study investigated morphological changes associated with soya bean meal-induced enteritis (SBMIE) in distal intestine (DI) of rainbow trout (Oncorhynchus mykiss) fed a soya bean meal (SBM)-based diet and exposed to normoxia or hypoxia created by optimal and low water flow rates, respectively. A 28-day adaption period was followed by a 42-day challenge period where 600 fish were subjected to dietary challenge and/or hypoxia. Twelve tanks each containing 50 juvenile trout were assigned randomly in triplicate to each treatment. Histopathological and immunohistochemical evaluation revealed pathological features that have not previously been described in association with SBMIE. Vacuolar degeneration of epithelial cells mainly at the base of mucosal folds, epithelial cysts, epithelial dysplasia, necrosis, shedding of necrotic cells, and granulomatous inflammation including infiltration of enlarged, sometimes finely vacuolated or "foamy" macrophages, multinucleated giant cells and increased proliferation of fibroblasts were observed. Acid-fast bacteria were not detected in enlarged macrophages; however, these cells contained AB-PAS- and sometimes cytokeratin-positive material, which was interpreted to be of epithelial/goblet cell origin. Hypoxia did not affect the morphological changes in DI. These results suggest that SBM was associated with a granulomatous form of enteritis in DI of rainbow trout regardless of water oxygen level.

Purification of Oil Contaminated Wastewater Using Sri Lankan Vein Graphite

Oil contaminated wastewater comes from variety of sources such as crude oil production, oilrefinery, petrochemical industry, metal processing, lubricants, cooling agents, car washing,and restaurants, etc. Oil is a highly visible pollutant and it reduces the levels of dissolvedoxygen in water and increases the level of toxic hydrocarbons. Therefor it affects the aquaticlife and water environment.Water and oil cannot be easily separated from oil-water mixtures, as oil exists in droplets inthe oil-water mixture. Oil droplets which are greater than or equal to 150 microns is classifiedas free oil while oil droplets with size ranging between 20 and 150 microns are classified asdispersed oil mixture. Emulsified oil mixtures are oil-water mixtures with droplets smallerthan 20 microns and oil-water mixture with droplet sizes smaller than 5 microns are classifiedas soluble oil mixtures.High purity vein graphite available in Sri Lanka is well renowned for electrical conductivityand lubricity. Beside it also has higher adsorption capacity. In this study, vein graphite ofdifferent particle sizes (<65, 65-125, 125-150 and 150-500μm) with two purity grades (99+%and 95%) were used to treat oil-water mixtures (motor engine oil with distilled water) similarto service station waste water of different concentrations of oil.Minimum amount of graphite (weight) required to completely separate oil from water wasmeasured in each treatment. Most effective particle size of graphite for this treatment wasfound to be in the range of 125-150 μm. Oil separation capacity of high purity graphite (99+%) and less pure (95%) graphite was found to be similar to each other. Maximumconcentration of oil that can be treated with this method was found to be 400%. Final oilconcentrations of all samples treated with graphite were measured and the efficiency of thetreatment was found to be 99.98%.Keywords: Natural vein graphite, Absorption capacity, Waste water, Hydrocarbon

Bioassay technique using seed shrimps for comparative studies regarding the aquatic acute lethality of biodegradable lubricants

To evaluate the environmental load resulting from the spillage of biodegradable lubricants in aquatic systems, a comparative acute lethality test wherein an oil–water interfacial area could be examined was considered. In this study, oleic acid was employed as a model biodegradable lubricant. Measurements of the pH value and dissolved oxygen (DO) level of water during the exposure tests indicate that water degradation depends on the oil–water interfacial area, exposure duration, and water temperature. Furthermore, 72 h acute lethality tests were performed using two types of freshwater ostracods (seed shrimps) as test organisms: the large species Stenocypris hislopi and the small species Cypretta seurati. The longevity of the small species, which was physically more active, was strongly affected by water pollution. During the exposure test, the DO in water was significantly consumed by the degradation of the lubricant floating on it. Water exposed to a lubricant containing copper (Cu) demonstrated strong toxicity even after the recovery of the pH value and DO level by aging. The decrease in the DO level of water and increase in the concentration of metal compounds are dominant factors responsible for the mortality of aquatic organisms.

After a Decade of Development: A Profile of Municipal Drinking Water Plants Utilizing a Sidestream Injection Process

The technology of rapid ozone mass transfer followed by degasification, the GDT™ Process, was first introduced in 1995 by Mazzei et al. At the time of introduction, municipal ozone installations utilized a low concentration, air-fed ozone gas as a disinfectant in atmospheric contact basins fitted with fine bubble diffusers (FBD). Over the past decade, air- fed ozone has given way to highly concentrated, oxygen-fed ozone. The change to concentrated oxygen feed gas has increased concerns about the corrosive effects of high finished water dissolved oxygen (DO). Water treatment plants using oxygen fed ozone have reported finished water DO levels in excess of 20 mg/L, with some plants resorting to air sparging at the back end of the contact basin to restore finished water to atmospheric gas levels. However, the evolution to oxygen feed gas has also produced significant cost benefits. Operating an ozone generator on oxygen increases its ozone production; reducing the size and capital cost of the generator needed to meet ozone output requirements. The use of a concentrated gas stream has also led to the development of side stream injection systems, which move the gas mixing out of the atmospheric basin and into the upstream pipeline (Neemann, 2002), resulting in a more compact contact basin design. Municipal water plants not having a CT requirement have streamlined one step further, by eliminating the ozone contact basin in favor of a sidestream injection Process. This paper reviews the technology of the GDT™ sidestream injection process and introduces 2 municipal water treatments plant (WTP) installations utilizing this process to remediate taste and odor compounds and as a method to reduce finished water dissolved oxygen concentrations.

Effects of hypoxia on renal function in carp, Cyprinus carpio

1. 1. Changes in urine and blood properties and heart rate (HR) of carp were investigated during and following hypoxia. 2. 2. When carp were exposed to hypoxic conditions, urine flow in some carp increased immediately. However, it decreased gradually with time. Osmotic pressure and Na +, Cl −1, Ca 2+ and Mg 2+ levels in urine increased in contrast to urine flow. K +, P, ammonium, and lactic acid levels in urine increased gradually. 3. 3. When carp lost their balance, blood pH and plasma K + were lower, and RBC, Ht, Hb, Mg 2+, P, ammonium, lactic acid, and glucose in plasma were higher than those of the control. 4. 4. As water-dissolved oxygen level was restored, urine flow increased immediately and soon decreased to the control rate. Other urine properties showed higher values than the initial levels and decreased with time. No significant change was found in urinary protein. 5. 5. The relationship between HR and urine flow is discussed.

Potential benefits of low energy water circulation in Hawaiian prawn ponds

Water temperature and pond water dissolved oxygen level are two parameters that are vitally important for optimization in aquaculture production. If the dissolved oxygen level falls below about 2 mg liter −1 and the water temperature drops to less than 22°C, freshwater prawns and other warmwater species of fish and invertebrates become stressed. That stress leads to decreased growth and survival, lower quality product, increased aggression, and reduced income. Artificial circulation of pond water can reduce oxygen stresses and thermal stratification, thereby alleviating conditions of poor water quality. Circulation with low energy pond mixers can increase benthic temperatures in thermally stratified ponds, uniformly distribute phytoplankton, and increase dissolved oxygen levels at the bottom of the pond. These benefits result in less aggression and cannibalism, increased survival, increased growth, and increased production.

Approximate BOD Treatment Requirements for Urban Runoff

The impact of storm-induced flows on receiving water dissolved oxygen levels is investigated for nine selected urban areas. Included are sites subject to combined sewer overflow as well as sites su...

Physicochemical conditions in temporary ponds in the New Forest

Seasonal fluctuations of the physicochemical conditions were recorded from five temporary ponds in the New Forest, over a period of two years. Diurnal fluctuations were also recorded. Physicochemical factors studied were pond volume; air, water and substratum temperature; water pH; water conductivity; and water dissolved oxygen level. The observed patterns of fluctuation are discussed and a concept of pond stability, to which the fluctuations may be related, is advanced.