scholarly journals Optimization of water flushing in lowland urban river in Jiaxing, Zhejiang using dissolved oxygen as the indicator

2018 ◽  
Vol 246 ◽  
pp. 02048
Author(s):  
Peiying Tan ◽  
David Z. Zhu ◽  
Yiping Zhang ◽  
Yongchao Zhou
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Urban River ◽  
Saturation Level ◽  
Evaluation Index ◽  
Urban Rivers ◽  
Time Intervals ◽  
Exponential Relationship ◽  
Do Concentration

River flushing has been considered as an effective tool for improving water quality in heavily polluted urban rivers. Dissolved oxygen (DO) as the evaluation index of water quality varied with time during and after water flushing. The time intervals between the flushing should be optimized such that the DO concentration remains above 2mg/L in the river. The duration between the flushing was found to be mainly correlated to the water temperature and the saturation level of dissolved oxygen. For the study river, when the temperature was below 15 ℃, there was an exponential relationship between the duration and saturation level of DO. For instance, the estimated duration was 157 hours or about 7 days for the subsequent flushing when the saturation level of DO was 90%. This duration was no more than 2 days when the temperature was above 15 ℃.

scholarly journals Electron generation in water induced by magnetic effect and its impact on dissolved oxygen concentration

2021 ◽  
Vol 31 (1) ◽  
Author(s):  
Augustine Chung Wei Yap ◽  
Hwang Sheng Lee ◽  
Joo Ling Loo ◽  
Nuruol Syuhadaa Mohd
Keyword(s):  
Water Quality ◽  
Hydrogen Bonding ◽  
Dissolved Oxygen ◽  
Electron Density ◽  
Water Flow ◽  
Magnetic Effect ◽  
Water Quality Control ◽  
Electron Generation ◽  
Magnetic Effects ◽  
Do Concentration

AbstractpH, oxidation-reduction potential (ORP) and dissolved oxygen (DO) concentration are important parameters in water quality surveillance and treatment. The changes of these parameters are associated with electron density in water. Several techniques including electrolysis and catalysis which require redox reactions and electron exchange are employed to improve these parameters. In recent years, studies reported that magnetic effects can impart considerable changes on the pH, ORP and DO concentration of water. However, the correlation between electron density and magnetic effects on these parameters has yet to be disclosed despite the fact that increased electron density in water could improve water’s reductive properties, heat capacity and hydrogen bonding characteristics. In this study, the magnetic effects on pH, ORP and DO concentration were investigated using different magnets arrangements and water flow rates based on reversed electric motor principle. Results showed that the improvement of pH, ORP and DO concentration from 5.40–5.42 to 5.58–5.62 (+ 3.5%), 392 to 365 mV (− 6.9%), and 7.30 to 7.71 mg L− 1 (+ 5.6%), respectively were achieved using combined variables of non-reversed polarity magnet arrangement (1000–1500 G magnetic strength) and water flow rate of 0.1–0.5 mL s− 1. Such decrement in ORP value also corresponded to 8.0 × 1013 number of electron generation in water. Furthermore, Raman analysis revealed that magnetic effect could strengthen the intermolecular hydrogen bonding of water molecules and favor formation of smaller water clusters. The findings of this study could contribute to potential applications in aquaculture, water quality control and treatment of cancer attributed to free radical induced-oxidative stress.

scholarly journals Limnology of Merbok estuary, Kedah, Malaysia

2015 ◽  
Vol 41 (1) ◽  
pp. 13-19
Author(s):  
Kaniz Fatema ◽  
Wan Maznah Wan Omar ◽  
Mansor Mat Isa
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Suspended Solids ◽  
Total Suspended Solids ◽  
Quality Parameters ◽  
The Other ◽  
Wet Season ◽  
Hand Temperature ◽  
Do Concentration ◽  
Merbok Estuary

Water quality in three different stations of Merbok estuary was investigated limnologically from October, 2010 to September, 2011. Water temperature, transparency and total suspended solids (TSS) varied from 27.45 - 30.450C, 7.5 - 120 cm and 10 -140 mg/l, respectively. Dissolved Oxygen (DO) concentration ranged from 1.22-10.8 mg/l, while salinity ranged from 3.5-35.00 ppt. pH and conductivity ranged from 6.35 - 8.25 and 40 - 380 ?S/cm, respectively. Kruskal Wallis H test shows that water quality parameters were significantly different among the sampling months and stations (p<0.05). This study revealed that DO, salinity, conductivity and transparency were higher in wet season and TSS was higher in dry season. On the other hand, temperature and pH did not follow any seasonal trends.Bangladesh J. Zool. 41(1): 13-19, 2013

scholarly journals Simulating Diurnal Variations of Water Temperature and Dissolved Oxygen in Shallow Minnesota Lakes

Water ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 1980
Author(s):  
Bushra Tasnim ◽  
Jalil A. Jamily ◽  
Xing Fang ◽  
Yangen Zhou ◽  
Joel S. Hayworth
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Shallow Lakes ◽  
Quality Model ◽  
Lake Water Quality ◽  
Ecological Processes ◽  
Turbulent Diffusion Coefficient ◽  
Hourly Data ◽  
Mean Square Errors

In shallow lakes, water quality is mostly affected by weather conditions and some ecological processes which vary throughout the day. To understand and model diurnal-nocturnal variations, a deterministic, one-dimensional hourly lake water quality model MINLAKE2018 was modified from daily MINLAKE2012, and applied to five shallow lakes in Minnesota to simulate water temperature and dissolved oxygen (DO) over multiple years. A maximum diurnal water temperature variation of 11.40 °C and DO variation of 5.63 mg/L were simulated. The root-mean-square errors (RMSEs) of simulated hourly surface temperatures in five lakes range from 1.19 to 1.95 °C when compared with hourly data over 4–8 years. The RMSEs of temperature and DO simulations from MINLAKE2018 decreased by 17.3% and 18.2%, respectively, and Nash-Sutcliffe efficiency increased by 10.3% and 66.7%, respectively; indicating the hourly model performs better in comparison to daily MINLAKE2012. The hourly model uses variable hourly wind speeds to determine the turbulent diffusion coefficient in the epilimnion and produces more hours of temperature and DO stratification including stratification that lasted several hours on some of the days. The hourly model includes direct solar radiation heating to the bottom sediment that decreases magnitude of heat flux from or to the sediment.

A study of water quality in an urban river and potential improvement using a prototype instream aerator

1989 ◽  
Vol 16 (3) ◽  
pp. 308-316 ◽  
Author(s):  
C. A. Town ◽  
D. S. Mavinic ◽  
B. Moore
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Data Base ◽  
Chlorophyll A ◽  
Late Summer ◽  
Urban River ◽  
Agricultural Activity ◽  
Fish Kills ◽  
Low Dissolved Oxygen ◽  
Oxygen Levels

Urban encroachment and intensive agricultural activity within the Serpentine–Nicomekl watershed (near Vancouver, B.C.) have caused a series of fish (salmon) kills on the Serpentine River since 1980. Low dissolved oxygen was responsible for these kills. This field project investigated some of the dynamic chemical and biological relationships within the river, as well as the use of an instream aerator as a temporary, in situ, water quality improvement measure. Weekly sampling for a 6-month period during the latter half of 1985 established a solid data base for deriving and interpreting meaningful interrelationships. A strong correlation between chlorophyll a and dissolved oxygen levels before the algae die-off supported the hypothesis that algae blooms dying in the fall could create a serious oxygen demand. Because of these environmental conditions, the river is unable to sustain healthy dissolved oxygen levels during this period. As such, a prototype, 460 m artificial aeration line was designed, installed, and monitored to evaluate its potential for alleviating low dissolved oxygen conditions and improving overall water quality during the critical fall period.The instream aerator ran continuously for over 2 months, starting in September 1985. Despite better-than-expected weather conditions (i.e., cool, wet weather) and relatively high dissolved oxygen levels during the fall of 1985, the data base appeared to support the use of this prototype aeration unit as a means of "upgrading" a stretch of an urban river subject to periodic, low dissolved oxygen levels. As a result, a 2-year follow-up study and river monitoring was initiated. In both 1986 and 1987, late summer and early fall river conditions resulted in the potential for serious salmon kills, due to higher-than-normal river temperatures and very low dissolved oxygen. In both instances, the instream aerator prevented such fish kills in a key stretch of the river. Expansion of the system to include other critical stretches of the Serpentine and other urban river systems, near Vancouver, is being considered. Key words: algae, aerator, chlorophyll a, eutrophic, fish kills, instream aeration, river improvement, urban river.

Impact of net pen aquaculture on lake water quality

2003 ◽  
Vol 47 (12) ◽  
pp. 293-300 ◽  
Author(s):  
J. Veenstra ◽  
S. Nolen ◽  
J. Carroll ◽  
C. Ruiz
Keyword(s):  
Water Quality ◽  
Organic Carbon ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Ictalurus Punctatus ◽  
Oxygen Demand ◽  
Total Alkalinity ◽  
Total Hardness ◽  
Army Corps ◽  
Lake Water Quality

A 3-year study was conducted by the U.S. Army Corps of Engineers assessing water quality related impacts of aquaculture of 250,000 channel catfish (Ictalurus punctatus) in floating net pens in the Rock Creek Arm of Lake Texoma, Oklahoma/Texas. Five large nylon nets suspended from a floating framework of galvanized metal anchored in open water 100 m offshore made up the net pens with fish stocking densities varying from 88 to 219 fish/m3. Water quality sampling was conducted biweekly from April to September and monthly from October to March at three locations. On all sampling dates field measurements of water temperature, pH, dissolved oxygen, and conductivity were recorded at 1 m depth intervals and water samples were collected at a depth of 0.5 m and near the bottom of the water column at each site. Sample analyses included: total alkalinity, total hardness, turbidity, chloride, sulfate, orthophosphate, total phosphorus, nitrate-N, nitrite-N, total Kjeldahl nitrogen, total organic carbon, dissolved organic carbon, biochemical oxygen demand, and chlorophyll a. The results showed statistically significant decreases in water temperature and dissolved oxygen and significant increases in field conductivity in surface waters near the net pens relative to other sampling sites. The most dramatic water quality effect observed during the study was decrease in dissolved oxygen levels near the net pens following lake turnover in the second year.

scholarly journals Analisis Kondisi Kualitas Air Pada Budidaya Ikan Kerapu Tikus (Cromileptes altivelis) Di Situbondo [Analysis Of Water Quality Conditions On Humpback Grouper Culture (Cromileptes altivelis) In Situbondo]

2019 ◽  
Vol 5 (1) ◽  
pp. 1
Author(s):  
Ervany Eshmat N, Abdul Manan
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Economic Value ◽  
International Markets ◽  
Fish Culture ◽  
Quality Analysis ◽  
Local Market ◽  
Descriptive Method

Abstract The humpback grouper (Cromileptes altivelis) is one of the fishery commodities with high economic value in both local and international markets. The price of humpback grouper can reach Rp. 200,000 - Rp. 400,000 / kilogram in the local market. The humpback grouper is potentially to be developed in most coastal areas of Indonesia. The conditions of water quality have a very important role for the success of fish culture of humpback grouper. To that end, monitoring and management of water quality are necessary in fish culture. The purpose of this case study is to determine the water quality conditions on humpback grouper culture in BBAP, Situbondo. The study was conducted on 16 January until 16 February 2012. The study method use descriptive method. From the results of water quality analysis, the water in humpback grouper broodstock ponds (I1 and I2) is no smell, no colour water, temperature 26.1-30 oC, salinity 27-35 ppt, dissolved oxygen 3.3-3.9 ppm, ammonia levels <0.001-0.22 ppm, nitrite levels 0.0075-0.085 ppm, alkalinity 110-120 ppm and pH 7.94-8.18. The water in humpback grouper hatchery ponds (B1 and B2) is no smell, green colour water, temperature 26.7-29.3 oC, salinity 27-34 ppt, dissolved oxygen 2.7-3.7 ppm, ammonia levels 0.0781-0.28 ppm, nitrite levels 0.0225-3.3305 ppm, alkalinity 94-126 ppm, and pH 7.14-7.81.

scholarly journals Electron generation in water induced by magnetic effect and its impact on dissolved oxygen concentration

2021 ◽  
Author(s):  
Augustine Chung Wei Yap ◽  
Hwang Sheng Lee ◽  
Joo Ling Loo ◽  
Nuruol Syuhadaa Mohd
Keyword(s):  
Water Quality ◽  
Hydrogen Bonding ◽  
Dissolved Oxygen ◽  
Electron Density ◽  
Water Flow ◽  
Magnetic Effect ◽  
Water Quality Control ◽  
Electron Generation ◽  
Magnetic Effects ◽  
Do Concentration

Abstract pH, oxidation-reduction potential (ORP) and dissolved oxygen (DO) concentration are important parameters in water quality surveillance and treatment. The changes of these parameters are associated with electron density in water. Several techniques including electrolysis and catalysis which require redox reactions and electron exchange are employed to improve these parameters. In recent years, studies reported that magnetic effects can impart considerable changes on the pH, ORP and DO concentration of water. However, the correlation between electron density and magnetic effects on these parameters has yet to be disclosed despite the fact that increased electron density in water could improve water’s reductive properties, heat capacity and hydrogen bonding characteristics. In this study, the magnetic effects on pH, ORP and DO concentration were investigated using different magnets arrangements and water flow rates based on reversed electric motor principle. Results showed that the improvement of pH, ORP and DO concentration from 5.40–5.42 to 5.58–5.62 (+ 3.5%), 392 to 365 mV (-6.9%), and 7.30 to 7.71 mg L− 1 (+ 5.6%), respectively were achieved using combined variables of non-reversed polarity magnet arrangement (1000–1500 G magnetic strength) and water flow rate of 0.1–0.5 mL s− 1. Such decrement in ORP value also corresponded to 8.0 × 1013 number of electron generation in water. Furthermore, Raman analysis revealed that magnetic effect could strengthen the intermolecular hydrogen bonding of water molecules and favor formation of smaller water clusters. The findings of this study could contribute to potential applications in aquaculture, water quality control and treatment of cancer attributed to free radical induced-oxidative stress.

scholarly journals Hydrodynamic Drivers of Dissolved Oxygen Variability within a Tidal Creek in Myrtle Beach, South Carolina

Water ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 1723 ◽  
Author(s):  
Douglas M. Pastore ◽  
Richard N. Peterson ◽  
Diane B. Fribance ◽  
Richard Viso ◽  
Erin E. Hackett
Keyword(s):  
Water Quality ◽  
South Carolina ◽  
Dissolved Oxygen ◽  
Tidal Creek ◽  
Water Levels ◽  
Beach Erosion ◽  
Shear Stresses ◽  
Myrtle Beach ◽  
Do Concentration ◽  
Face Morphology

Beach erosion and water quality degradation have been observed in Singleton Swash, a tidal creek that traverses the beach-face connecting land and ocean in Myrtle Beach, SC. The objective of this study in Singleton Swash is to explore relationships between water quality and hydrodynamics, where the latter are influenced by beach face morphology. We measure water velocities, water levels, and dissolved oxygen concentrations (DO) (a proxy for water quality) and apply correlation analysis to examine the relationships between physical processes and dissolved oxygen variations. Results show that larger tidal ranges are associated with higher mean levels of DO in the tidal creek. The larger tidal ranges are linked to larger magnitude currents, which increase both the DO transport via larger fluxes of oxygenated oceanic water into the swash and the magnitude of Reynolds shear stresses; due to tidal asymmetries, flood currents are stronger than ebb currents in this system. Based on these results, it is concluded that the combined transport of oxygenated waters into the tidal creek from the ocean on large flood tides and subsequent mixing due to large Reynolds shear stresses result in the observed net DO concentration increases in the creek over tidal cycles.

Hydrology and Water Quality Survey Near the Gezhouba Dam in the Winter

2013 ◽  
Vol 726-731 ◽  
pp. 3256-3261
Author(s):  
Jia Fei Zhou ◽  
Cong Feng Wang ◽  
De Fu Liu ◽  
Jing Wen Xiang ◽  
Ping Zhao ◽  
...  
Keyword(s):  
Water Quality ◽  
Dissolved Oxygen ◽  
Water Temperature ◽  
Flow Velocity ◽  
Water Column ◽  
Quality Data ◽  
Chinese Sturgeon ◽  
Water Quality Data ◽  
Gezhouba Dam ◽  
Survival Condition

Filed hydrology and water quality data were collected near the Gezhouba Dam early December of 2012 to analyze the response of Chinese Sturgeon survival condition to water temperature, dissolved oxygen (DO), pH, transparency (SD) and bottom flow-velocity. The results showed that water temperature lag is unconspicuous. The water temperature of Gezhouba Dam Sanjiang (GDS) was lower than that of Gezhouba Dam River (GDR), and it hindered propagation of sturgeon eggs. DO decreased fast in the vertical water column of GDS, pH ranged from 7.5 to 7.71. The hydrology and water quality were suitable for the life condition of sturgeon eggs and fry, except index of bottom flow-velocity.

scholarly journals Changes in the nitrogen biogeochemical cycle in sediments of an urban river under different dissolved oxygen levels

2018 ◽  
Vol 19 (4) ◽  
pp. 1271-1278 ◽  
Author(s):  
Yaping Zhang ◽  
Xiaohong Ruan ◽  
Wenli Shi
Keyword(s):  
Dissolved Oxygen ◽  
Nitrogen Cycling ◽  
Quantitative Polymerase Chain Reaction ◽  
Nitrogen Transformation ◽  
Urban River ◽  
Ammonia Oxidizing Bacteria ◽  
Urban Rivers ◽  
Ammonium Oxidation ◽  
Microbial Nitrogen ◽  
Concentration Changes

Abstract Urban rivers are considered as a hot spot of microbial nitrogen cycling due to extensive N loading. However, microbial nitrogen transformation dynamics in urban rivers with different dissolved oxygen (DO) conditions are still unclear. This study investigated the effects of DO concentration changes (anaerobic to aerobic) in overlying water on nitrogen-cycling gene abundance in incubation conditions using sediment from a typical urban river in the Yangtze River Delta. Quantitative polymerase chain reaction (qPCR) results revealed that the abundances of the nitrification gene amoA, denitrification gene nirS/K, norB, nosZ, and anammox gene hzo increased by one to two orders of magnitude from anaerobic to aerobic conditions. Ammonia-oxidizing archaea (AOA) predominated the ammonium oxidation microbial populations, about tenfold more than the ammonia-oxidizing bacteria (AOB) populations. Significant correlations were found among the abundances of AOA-amoA, AOB-amoA, nirS, nirK, and hzo genes, implying a close coupling of aerobic ammonium oxidation (AAO), denitrification, and anammox processes at the molecular level. Moreover, the nitrogen transformation rates were calculated using a box model linking the measured dissolved inorganic nitrogen species. The contribution of anammox to N2 production was 85% under saturated treatment, and the AAO rate was significantly positive correlated to the anammox rate. Our results suggested that coupled AAO and anammox might be the dominant pathway for reactive nitrogen removal in urban rivers with elevated DO levels.

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